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ACTA OPHTHALMOLOGICA

A population based follow-up study on pseudoexfoliation and cataract surgery
Reviewed by: Bheemanagouda Patil
Vol 22 no 6
 

An association between pseudoexfoliation (PEX) and cataracts has been shown in many previous studies. Recently, the Australian Blue Mountains Eye Study, using the Wisconsin Cataract Typing and Grading System, observed an increased prevalence of nuclear cataract in eyes with PEX. The purpose of this study was to study the relationship between PEX and cataract surgery in a cohort comprising a substantial number of exposed individuals. Survival analyses were performed in a cohort of 760 residents 65-74 years of age, examined in a population survey in the municipality of Tierp, Sweden, during 1984-1986. Additionally, subjects were recruited by means of glaucoma case records established at the Eye Department in Tierp in 1978–2007. In total, the cohort comprised 1471 individuals, representing more than 15,900 person-years of risk. Information on cataract surgery was obtained from the glaucoma case records and from medical records. By the end of the study in August 2014, 564 subjects had undergone cataract surgery. Of these cases, 224 were affected by PEX at baseline. In multivariate analyses, PEX was the second most important predictor for cataract surgery after lens opacities, accounting for a 2.38-fold (95% confidence interval 2.01–2.84) increased risk. 

Reference

Pseudoexfoliation and cataract surgery: a population-based 30-year follow-up study.
Ekstrom C, Taube AB.     
ACTA OPHTHALMOLOGICA
2015;93:774-7. 

AMERICAN JOURNAL OF OPHTHALMOLOGY

OCT angiography and retinal vein occlusions
Reviewed by: Efrosini Papagiannuli
Vol 22 no 6
 

In this retrospective, observational case series, the authors set out to evaluate the morphology of the superficial and deep capillary plexa of eyes that suffered a retinal vein occlusion (RVO) on OCT angiography (OCTA) and compare the findings with fluorescein angiography (FA) and spectral domain optical coherence tomography (SD-OCT). The case notes were reviewed of 54 consecutive patients with unilateral RVO that had occurred between October 2014 and March 2015. Of these 29 had CRVO and 25 branch retinal vein occlusion (BRVO). Three patients with RVO had to be excluded due to poor quality of scan images. Excluded were eyes with diabetic retinopathy, previous retinal surgery, pathologic myopia or trauma. The parameters used to assess any capillary network abnormalities included disruption of the capillary network, capillary dilation and presence of shunting vessels, and well defined roundish black foci on OCTA (likely intraretinal cystoid spaces). The presence of any perifoveal capillary arcade disruption was also assessed in the superficial plexus (only visible here). All these OCTA findings were documented both for the superficial and deep capillary plexus and compared with FA and SD-OCT findings. The perifoveal capillary arcade was visible in 96% on OCTA and 83% on FA. It was disrupted in 92% on OCTA and 72% on FA (p=0.002). This disruption was correlated with peripheral retinal ischaemia (p=0.025). Intraretinal cystoid spaces were seen in 68% on FA, 76% on SD-OCT and 90% on OCTA. Retinal capillary network disruptions were seen in all patients in both superficial and deep plexa on OCTA. However, non-perfused (grayish) areas were more common in the deep plexus (84%) than the superficial (59%) (P<0.001). Best corrected visual acuity was correlated with the presence of macular ischaemia on FA (P=0.018), but not with any of the OCTA abnormalities. The authors point out that their study has for the first time highlighted the involvement of the deep capillary plexus in RVO and that the level of hypo-perfusion is more extensive here than in the superficial plexus. They argue that OCTA is a better imaging modality to capture the capillary plexa and arcade, as well as detecting retinal cystoid spaces. They speculate that the poorer visualisation of these structures on FA, may be due to the missing of early frames, focusing problems in the presence of extensive macular oedema, media opacities, and capillary dye leakage. Furthermore, FA is an invasive investigation with various potential side-effects. Whilst they advocate the use of OCTA as a non-invasive technology, which can easily be repeated, they are aware of its own limitations, such as the small scanning window (3x3 mm), possible artefacts that can hinder the view of the vascular bed, the softwares inability for accurate distinction of the capillary plexa (because of structural disorganisation after macular oedema) and the fact that OCTA can mask laser scars, because they are interpreted as no-flow areas by the software. Nevertheless the authors are in favour of the potential of this new imaging modality to enhance our management of RVOs, and at present are undertaking further studies with OCTA evaluating the macular oedema and perfusion in treated RVO. 

Reference

Optical coherence tomography angiography in retinal vein occlusion: evaluation of superficial and deep capillary plexa.
Coscas F, Glacet-Bernard A, Miere A, et al.
AMERICAN JOURNAL OF OPHTHALMOLOGY
2016;161:160-71.

AMERICAN JOURNAL OF OPHTHALMOLOGY

What effects do repeated Ozurdex implants have in paediatric uveitis?
Reviewed by: Efrosini Papagiannuli
Vol 22 no 6
 

The aim of this retrospective study was to assess the anatomical and functional results, as well as complications of repeated Ozurdex intravitreal implants in a paediatric (non-infectious) uveitis cohort. Twenty-two eyes (16 patients) received 35 Ozurdex implants over a six year period. Fourteen eyes had intermediate and eight eyes posterior uveitis or panuveitis. The aetiology in 15 eyes was idiopathic, pars planitis in three eyes, juvenile idiopathic arthritis in two eyes and Vogt-Konyanagi-Harada disease in two eyes. The average patient age at the time of the first implant was 13 +/- 0.7 years, nine patients were on treatment with systemic steroids and 11 patients had previously been treated with immunosuppressants (eight with mycophenolate mofetil, three infliximab, two azathioprine, two methotrexate,one cyclosporin). Of these 11 patients, four were still on immunosuppressants (three mycophenolate mofetil, one infliximab). There were four eyes that had previous orbital floor steroid injections and eight eyes that had received intravitreal Triamcinolone. The Ozurdex injections were performed under general anaesthesia, in patients who had previously responded well to a periocular steroid injection, could not tolerate systemic treatment, or low does systemic treatment was ineffective. There was cystoid macular oedema (CMO) in 77.3% and vitritis in 22.3%. Outcome measures included visual acuity (BCVA), central retinal thickness (CRT), systemic immunosuppression (number and dosage of drugs), vitreous haze score, and presence of cataract or elevated intraocular pressure (IOP>21 mmHg). Data was collected on the day of implantation, months one, two, three, six, 12, 18, 24 and last follow-up. The results were encouraging, as after the first implantation the BCVA improved significantly from 0.55 +/-0.08 to 0.37+/-0.08 LogMAR (p=0.024), CRT decreased by 219+/- 55 microns (p=0.01) and a vitreous haze score of 0 was achieved in 88% of eyes (up from 41%, p=006). Average follow-up time was 16.1+/-2.1 months after the first implant. Thirteen eyes (59.1%) received only one Ozurdex implant and nine eyes (40.9%) required multiple implants. The median time to relapse was nine months and all children who were using systemic immunosuppression could either stop it or decrease both the number of drugs used and their dose. The average time to restarting systemic treatment was 16.1+/-2.5 months. In terms of side-effects, there were six eyes with an increase in IOP, of which five responded to pharmacological treatment and one required revision of a previous glaucoma procedure. There were also four eyes with a visually insignificant lens opacity that did not require any intervention. No endophthalmitis, retinal detachment or implant migration was reported. The authors conclude that despite the need for general anaesthesia, Ozurdex implants are a valuable option in treatment resistant paediatric uveitis with an acceptable side-effect profile. They advocate close monitoring of these patients as they are at risk of amblyopia due to lens opacities and recommend prompt surgical treatment when visually significant cataracts develop, in order to preserve visual function. They highlight the limitations of their study in terms of study design (retrospective) and small patient numbers and recommend further studies to examine the possible development of longer-term complications.

Reference

Outcome of treating pediatric uveitis with dexamethasone implants.
Tomkins-Netzer O, Talat L, Greenstein SS, et al.
AMERICAN JOURNAL OF OPHTHALMOLOGY
2016;161:110-5.

BRITISH JOURNAL OF OPHTHALMOLOGY

Clinical evaluation of a new pupil independent diffractive MIOL lens with a ±2.75D near addition
Reviewed by: Jonathan Chan
Vol 22 no 6
 

This is a clinical outcome assessment after cataract surgery with implantation of multifocal intraocular lens implant IOL with a lower near addition (+2.75D) of 143 eyes of 85 patients aged between 40 to 83 years of age. The type of lens implant used was multifocal IOL (MIOL) Tecnis ZKB00. The changes in uncorrected and corrected Log-MAR distance, intermediate visual acuity and near visual acuities, as well as manifest refraction were evaluated during a three month follow-up period. The patients were also asked about photic phenomena and spectacle dependence. The postoperative spherical equivalent was within ±0.5 dioptres and ±1 dioptre of emmetropia in 78.1% and 98.4% of eyes, respectively. The postoperative mean monocular uncorrected distance visual acuity, uncorrected near visual acuity and uncorrected intermediate visual acuity was 0.20 Log-MAR or better in 73.7%, 81.1% and 83.9% of eyes, respectively. All eyes achieved monocular corrected distance visual acuity of 0.30 Log-MAR or better. All patients were at least moderately happy with the outcomes of the surgery. Only 15.3% of patients required glasses correction postoperatively from daily activities. The postoperative complications include four eyes requiring Femto-LASIK re-treatment to correct the residual refractive error (2.8% 4/143 eyes). Regarding photic phenomena, 19 patients (33.9%) referred the perception of some type of halos (21.4%) or right glare (14.3%). Only in three patients (5.4%) were these photic phenomena referred to as moderate degree. The authors conclude that the introduction of this low add of +2.75D multifocal lens implant follows a trend to increase intermediate visual acuity reaching satisfying near results and high patient satisfaction for intermediate visual acuity. The limitations of the study according to the authors include no controlled group was included in this study and also the lack of validated questionnaires to evaluate patient satisfaction and photic phenomena. In addition, the defocus curve was not measured in this study and also the contrast sensitivity was not measured either. They recommended a further multicentre prospective larger study in the future to compliment this pilot study. 

Reference

Clinical evaluation of a new pupil independent diffractive multifocal intraocular lens with a ±2.75 D near addition: a European multicentre study. 
Kretz FT, Gerl M, Gerl R.
BRITISH JOURNAL OF OPHTHALMOLOGY
2015;99:1655-9.

BRITISH JOURNAL OF OPHTHALMOLOGY

SS-OCT assessment of ITC after phacoemulsification
Reviewed by:
Vol 22 no 6
 

This is a multicentre randomised controlled trial of 22 patients with primary angle closure glaucoma with peripheral anterior synechia and peripheral primary angle closure glaucoma (PACG) with peripheral anterior synechia (PAS) detected by indentation gonioscopy was randomised into two groups. The first group is phacoemulsification only (PE (n=11)) and phacoemulsification + goniosynechialysis (GSL) (n=11). These patients were compared with the change in the iris-trabecular contact (ITC) area using swept–source optical coherence tomography (SS-OCT) in eyes with primary angle closure glaucoma and that had cataract surgery with phacoemulsification and lens implantation. The anterior chamber angles were evaluated by SS-OCT under dark conditions before and 12-months after surgery using three-dimensional angle analysis scan protocol that simultaneously obtains 128 cross-sectional radial scans across the anterior chamber at equal intervals (every 1.4°). The ITC area, defined as an area of the extent of the circumferential contact of the peripheral iris to the angle wall, was computed automatically by SS-OCT after and observer marked the scleral spurs of all 128 scans of each eye. Of the patients, 77.3% were women with a mean age ±SD of 67.3 ≥5.8 years. The ITC area was significantly reduced in the PE+GSL group compared with the PE alone group (10.2mm2 vs 4.6mm2, β= 0.54, p=0.03) after adjusting for age, gender, intraocular pressures, extent of PAS and pupil diameters before surgery. Smaller iris volumes at baseline was associated with greater ITC area reduction by PE+GSL (β=0.728, p=0.03). The authors conclude that patients that had PE+GSL surgery have a greater reduction in circumferential ITC area than eyes that undergo PE alone. The authors also comment the limitations of this study include the use of a single observer for gonioscopy and SS-OCT image grading, which could result in a systematic bias. In addition, the sample size was relatively small and 12-months could be too short a period to evaluate the long-term outcome of the ITC area changes with time. The limitation of the clinical detection and quantification of PAS could also be variable. 

Reference

Swept-source optical coherence tomography assessment of iris-trabecular contact after phacoemulsification with or without goniosynechialysis in eyes with primary angle closure glaucoma.
Tun TA, Baskaran M, Perera SA, et al.
BRITISH JOURNAL OF OPHTHALMOLOGY
2015;99:927-31.

CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY

Aflibercept for the treatment of neovascular glaucoma
Reviewed by: Anjali Gupta
Vol 22 no 6
 

The aim of this study was to investigate initial results regarding the treatment of neovascular glaucoma (NVG) with intravitreal aflibercept. NVG is classified into stages 0-3. In stages 1 and 2, abnormal vessel proliferation is seen with or without elevated IOP, but with an open anterior chamber angle. In stage 3, fibrovascular contraction leads to the development of peripheral anterior synechiae and subsequent secondary angle closure. This study was a prospective interventional case series recruiting patients with newly diagnosed stage 1 or 2 NVG. Four patients were recruited into the study. Each patient received 2mg intravitreal aflibercept at day one with planned additional injections at four weeks, eight weeks and at eight week intervals throughout the study duration (52 weeks). Intravitreal aflibercept resulted in rapid regression of neovascularisation of the iris and angle (NVI, NVA). IOP was stable or reduced in all patients at the final follow-up of 52 weeks. The authors conclude that intravitreal aflibercept may be an effective treatment for stage 1 and stage 2 NVG. The advantage of aflibercept when compared to the traditional treatment of laser panretinal photocoagulation (PRP) for NVG is preservation of the retina, as PRP can cause visual field defects and reduced colour vision and contrast sensitivity. This study is limited by the small sample size and the absence of control subjects and further trials are warranted for the use of intravitreal aflibercept in NVG. 

Reference

Aflibercept for the treatment of neovascular glaucoma.
SooHoo JR, Seibold LK, Pantcheva MB, Kahook MY.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2015;43:803-7.

CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY

Comparison of SS-OCT and SD-OCT in polypoidal choroidal vasculopathy
Reviewed by: Anjali Gupta
Vol 22 no 6
 

Swept source OCT (SS-OCT) is known to have a longer wavelength than spectral domain OCT (SD-OCT), allowing deeper penetration into retinal and choroidal layers. The aim of this study was to investigate whether SS-OCT is superior to SD-OCT in imaging important retina and choroidal features in polypoidal choroidal vasculopathy (PCV). Twenty eyes from 20 patients with treatment naïve PCV at a single centre were included in this study. Patients were diagnosed with PCV on ICGA findings by two retina specialists using the EVEREST criteria. All patients had an ocular examination and imaging with FFA, ICGA, SS-OCT and SD-OCT. Two retina specialists graded pre-specified OCT features for both the SS-OCT and SD-OCT in all patients. The pre-specified OCT features included presence of 1) a polyp, 2) a sharp and peaked pigment epithelial detachment (PED), 3) a notched PED, ability to visualise, 4) the full height of the PED, 5) the inner segment / outer segment (IS/OS) line, 6) the RPE line and 7) the choroid-scleral interface (CSI). Detection rate and agreement between the two OCTs were compared. At least one PCV lesion was detected in 17 eyes with SD-OCT and in 18 eyes using SS-OCT. Sharp peaked PED and notched PED were detected on both SD-OCT and SS-OCT in the majority of eyes. However, IS/OS line and CSI were visible in only nine eyes with SD-OCT compared with the IS/OS line being visible in 13 eyes and the CSI visible in 16 eyes using SS-OCT. The authors conclude that SS-OCT is superior in detecting the CSI but has comparable visibility for the other retina features in PCV when compared with SD-OCT. 

Reference

Comparison of swept source optical coherence tomography and spectral domain optical coherence tomography in polypoidal choroidal vasculopathy.
Ting DSW, Cheung GCM, Lim LS, Yeo IYS.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2015;43:815-9.

CORNEA

Central corneal and epithelial thickness measured by Fourier domain OCT
Reviewed by: Magdalena Popiela
Vol 22 no 6
 

This study examined intraobserver and interobserver reproducibility of corneal thickness (CT) and epithelial thickness (ET) measurement of Fourier domain OCT (RTVue) in 23 healthy volunteers. RTVue is capable of producing 26,000 A scans per second with depth resolution of 5µm. All patients underwent three sessions of examinations, totalling nine CT and ET measurements each. Sessions were taking place at different times during a day (9am and 4pm) and 9am the next day. CT and ET were evaluated at nine different corneal locations. The intraobserver and interobserver reproducibility was almost perfect for both CT and ET at most measured locations and substantial for six and 12 o’clock locations. Interestingly data showed significant difference in CT and ET between morning and afternoon measurements. CT and ET were significantly thinner in the afternoon by -3.15µm and -0.52µm respectively. This might be secondary to overnight swelling and daily detumescence of the cornea secondary to reduced oxygen level and evaporation of tear film beneath the closed eyelids. This may represent physiological changes in CT and ET, but values are below the manufactures depth resolution, therefore need to be looked at with caution. 

Reference

Reproducibility and daytime-dependent changes of corneal epithelial thickness and whole corneal thickness measured with Fourier domain optical coherence tomography. 
Wasielicka-Poslednik J, Lisch W, Bell K, et al.
CORNEA 
2016;35(3):342-9.

CORNEA

Corneal tattooing as treatment for bullous keratopathy
Reviewed by: Magdalena Popiela
Vol 22 no 6
 

This retrospective study looked at differences in epithelial smoothing in patients with bullous keratopathy (BK) undergoing either corneal tattooing or anterior stromal puncture (ASP). Both procedures were carried out for symptomatic relief in eyes with poor visual potential. Chinese ink was introduced into the cornea with 25G or 27G needle in the area of bullae formation. After procedure both groups used bandage contact lenses and antibiotic drops to promote re-epithelisation. Thirty-one patients treated with corneal tattooing had statistically significant reduction in bullae formation compared to nine patients treated with ASP at three months. Of the 90.3% of patients in corneal tattooing group 90.3% were symptom free at three months, whereas 100% of ASP treated patients were still symptomatic at the same time point. The authors postulate that Chinese ink injected into corneal stroma induces inflammatory reaction within the cornea which results in stronger epithelium adhesion and reduction in bullae formation. This, however, has not been histologically evaluated. Although a small sample with short follow-up, corneal tattooing seems to be an interesting treatment option for patients with BK and poor visual potential. Further reports of more patients with longer follow-ups are needed to prove if indeed corneal tattooing is a valuable long-term option for BK patients to relieve their symptoms. –

Reference

Corneal tattooing and anterior stromal puncture for treating symptomatic bullous keratopathy.
Lin HC, Wang YL, Chen G, et al. 
CORNEA 
2016;35(3):355-7.

CORNEA

Dry eyes after photorefractive keratoplasty
Reviewed by: Magdalena Popiela
Vol 22 no 6
 

This study examined changes in tear break up time (TBUT), Schirmer test, tear osmolarity and dry eye questionnaire (OSDI) score from prior to photorefractive keratoplasty (PRK), to two months and four months postoperatively. Fifty eyes of 25 patients were examined. Patients used artificial tears up to two months post PRK. All measured parameters showed significant worsening at two months post surgery compared to values measured beforehand, despite the regular use of artificial teardrops. At four months values for Schirmer test and tear osmolarity have improved and were comparable to ones recorded before the PRK. Tear break up time also improved at four months but remained significantly worse compared to prior the surgery. OSDI score followed a reverse trend, where values at four months post PRK were significantly better compared to before the surgery. This study confirms dry eye as a frequent but transient complication of PRK. It is a first report of changes in tear osmolarity in patients undergoing photorefractive keratectomy.

Reference

Evaluation of tear osmolarity changes after photorefractive keratectomy.
Beheshtnejad A, Hashemian H, Kermanshahani A, et al.
CORNEA
2015;34(12):1541-4

EXPERIMENTAL EYE RESEARCH

Nanofiber-based hydrogels prevent capsular opacification
Reviewed by: Graham Wallace
Vol 22 no 6
 

Lens refilling is the replacement of the lens with a silicone polymer in an otherwise intact lens capsule. However, capsular opacification (CO), resulting in reduced visual acuity, is a major complication of these injectable accommodating lenses. Opacification is due to differentiation of lens epithelial cells (LES) into myfibroblasts via epithelial to mesenchymal transformation (EMT). In this paper using a porcine eye model, after the removal of natural lens fibres, nanofiber-based hydrogels decorated with signaling peptides chosen for their potential to influence molecules such as laminin, fibronectin and collagen, were injected. Interaction between the peptides and LEC were assessed for the ability to inhibit EMT. Compared to hyaluronan controls hydrogel-treated eyes had less CO by α-smooth muscle actin expression. LEC differentiation was further reduced in hydrogels linked to peptides. Nanofiber hydrogels targeting biological pathways in EMT provide a potential novel therapy in reducing capsular opacification. 

Reference

Nanofiber-based hydrogels with extracellular matrix-based synthetic peptides for the prevention of capsular opacification. 
Nibourg LM, Gelens E, de Jong MR, et al.
EXPERIMENTAL EYE RESEARCH 
2016;143:60-7

EXPERIMENTAL EYE RESEARCH

Resveratrol protects against steroid induced intraocular pressure
Reviewed by: Graham Wallace
Vol 22 no 6
 

Topical and systemic steroid delivery is a very effective treatment for many ocular conditions but is compromised by raised intraocular pressure which in turn leads to death of retinal ganglion cells and irreversible blindness. This is an important consideration with intraocular steroid release devices. Steroid-induced hypertension is associated with increased extracellular matrix deposition in the trabecular meshwork inhibiting outflow of aqueous humour. Resveratrol is a polyphenol found in grapes, wine and other plants. It has been linked to protective effects in heart disease and diabetes, and extending lifespan, due to antioxidant properties, although evidence in humans is not yet available. Previous studies by the authors have shown that a single topical treatment of trans-resveratrol in rats with steroid induced ocular hypertension (SIOH) reduced ocular hypertension. This was shown to be due to activation of adenosine A1 receptors and possible matrixmetalloproeinase-2 activity. In this study, trans-resveratrol topical administration was given twice daily, bilaterally to rats with or without SIOH. Treatment with trans-resveratrol significantly reduced IOP in animals with SIOH, associated with increased aqueous humour MMP-2 levels. TM thickness and cell number was reduced in treated animals, and the ganglion cell layer and inner retinal thickness were significantly increased. Finally, retinal oxidative stress was significantly decreased by treatment. These results support the use of trans-resveratrol in SIOH with positive effects on both the anterior and posterior segments of the eye.

Reference

Topical trans-resveratrol ameliorates steroid-induced anterior and posterior segment changes in rats. 
Razali N, Agarwal R, Agarwal P, et al.
EXPERIMENTAL EYE RESEARCH 
2016;143:9-16.

EXPERIMENTAL EYE RESEARCH

Treatment of Sjogren’s Syndrome dry eye in mouse model
Reviewed by: Graham Wallace
Vol 22 no 6
 

Sjogren’s syndrome (SS) is a chronic autoimmune disease characterised by inflammation of the exocrine glands, specifically the salivary and lacrimal glands that produce saliva and tears, respectively. The immune-mediated attack on the salivary and lacrimal glands leads to the development of dry mouth and eyes, associated with lymphocytic infiltration of the tissues. Cell adhesion molecules play a key role in leucocyte trafficking into tissues and blockade of these molecules has been effective in other autoimmune conditions such as multiple sclerosis. Increased expression of adhesion molecules has been reported in SS. In this paper animals deficient in thrombospondin-1 (TSP-1) that develop features similar to SS, were treated with an antagonist to integrin α4, (GW559090) which has a high affinity for integrin α4β1 inhibiting the interaction with VCAM-1 and fibronectin. The results show that topical administration of GW559090 significantly reduced corneal barrier disruption as shown by fluorescein staining, reduced corneal expression of IL-1β, and an increase in goblet cell numbers compared to control untreated animals. The results for GW559090 were comparable to topical administration of dexamethasone. These results show that inhibition of migration of cells into ocular tissue may be effective in preventing progression of SS, and may be a new therapeutic option in humans with this disease.

Reference

Sjogren’s syndrome associated dry eye in a mouse model is ameliorated by topical administration of integrin α4 antagonist GW559090. 
Contreras-Ruiz L, Mir FA, Turpie B, et al. 
EXPERIMENTAL EYE RESEARCH 
2016;143:1-8. 

INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE

Association between serum levels of testosterone and estradiol with meibomian gland assessments in postmenopausal women
Reviewed by: Wai Siene Ng
Vol 22 no 6
 

This study aims to reveal any correlation between serum levels of testosterone and estradiol in postmenopausal women with meibomian gland dysfunction. Postmenopausal subjects were defined as amenorrhoea for at least one year with low follide stimulating hormone (FSH) and estradiol. Exclusion criteria include ocular surgery within the previous year and any anterior segment disease. However, women on hormone replacement therapy were included. To demonstrate any effect from this a subgroup analysis was performed which showed no difference. Meibomian gland assessments included in the study were expressibility of meibum, meibum quality, meibomian gland dropout by and lipid layer thickness by spectral interferometry. Estradiol and testosterone serum levels were taken from venous blood samples. However, the time of blood sampling was not described which may be pertinent due to the diurnal variations of hormones and their well-reported bias effect if not taken into account. The authors also proceed to divide the cohort into dry eye or normal based on a Schaumberg questionnaire. However, as the questionnaire relies on the patient self-reporting a diagnosis of dry eye, its validity is questionable. The only objective outcome in the meibomian gland assessments was lipid layer thickness. However, this returned a contradicting result with the dry eye group having a thicker lipid layer. The rest of the assessments were subjective and lacked assessor method description and validation. Hence, it comes as no surprise that there was no significant difference found in estradiol levels and testosterone levels for dry eye of meibomian gland assessment apart from that seen between severe and mild meibomian gland dropout cases and increased testosterone levels. Overall, the study attempts to address the relation between postmenopausal dry eye and meibomian gland dysfunction with estradiol and testosterone with in depth meibomian gland analysis. Improvement in the diagnostic criteria for dry eyes and consistent times for obtaining blood samples may help reveal subtle associations between sex hormones and postmenopausal dry eyes in future studies. 

Reference

Association between serum levels of testosterone and estradiol with meibomian gland assessments in postmenopausal women. 
Ablamowicz AF, Nichols JJ, Nichols KK.
INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE
2016;57:295-300.

INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE

RTP801 as a neuroprotective and axon regenerative treatment
Reviewed by: Wai Siene Ng
Vol 22 no 6
 

This paper describes the neuroprotective and axon regenerative effects of siRTP801, which is a translatable small-interfering RNA (siRNA) targeting mTOR negative regulator; RTP801, through in-vivo and in-vitro models. In-vivo studies involved an optic nerve crush rat model with intravitreal injections of siRTP801 on days zero, eight and 16 post crush. Intravitreal injection of siEGFP served as a model in the contralateral eye as well as a group of uninjured animals as intact controls. At day 24 tissue was harvested for immunohistochemistry and analysis of retinal ganglion cell (RGC) survival, axonal regeneration, glial activation, RTP801 expression and mTOR activity by detecting ps6 expression; a downstream indicator of mTOR activity. In-vitro studies involved mixed retinal cell cultures that were lipofected with siRTP801 and siEGFP and treated with rapamycin which are then tested for NGF, NT-3 and BDNF levels, number of surviving βIII tubulin+ RGC and number of GFAP+ activated glia. They found treatment with siRTP801 promoted increase in Brn3a+ RGC survival at 24 days post optic nerve crush, supporting its neuroprotective role. It also promoted longer growth of regenerating axons. In-vitro studies showed that this was not initiated in the absence of activated retinal glia. Further work showed siRTP801 did not promote glial proliferation and only reduced RTP801 expression. However, GFAP+ activated glia were present in retinal cultures five days post optic nerve crush, indicating this to be an injury response. Furthermore, neurotrophin titres were increased; NGF in particular, for retinal cultures post crush but not in cultures where glia were absent. This suggests that siRTP801 potentiates neurotrophin production but not without the initiation of it by optic nerve crush injury. This study elegantly supports RTP801 as a neuroprotective and axon regenerative treatment and outlines a mechanism of action via potentiation of PI3K pathway signaling in RGC causing paracrine secretion of neurotrophins by activated glia. 

Reference

siRNA-mediated knockdown of the mTOR inhibitor RTP801 promotes retinal ganglion cell survival and axon elongation by direct and indirect mechanisms. 
Morgan-Warren PJ, O’Neill J, de Cogan F, et al.
INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE
2016;57:429-43.

JOURNAL CATARACT REFRACTIVE SURGERY

Implantation of diffractive trifocal intraocular lens
Reviewed by: Sharmina Khan
Vol 22 no 6
 

This study reports on 60 eyes of 120 patients who underwent routine cataract surgery followed by implantation of the trifocal IOL model Lisa tri-839MP. This is a diffractive trifocal preloaded IOL with no interruption at the haptic-optic junction, 360 degrees square edged to prevent posterior capsular opacification. All cases are performed by a single surgeon. Inclusion criteria were patients with less than 1.25 dioptres of corneal astigmatism with cataract or clear lens seeking spectacle independence. All patients underwent defocus curve assessment, which is when a sequential series of minus and plus lenses are used to simulate different distances over which a patient’s vision is evaluated. The results showed that at one month postoperatively there was no significant improvement in near and intermediate visual acuities and only distance acuity. Between one month and 12 months there was a progressive improvement in uncorrected intermediate acuity. In the defocus curve no significant differences were found between visual acuities corresponding to defocus levels of -1.0 D and -2.0 D. Ocular aberrations decreased statistically significantly at six to 12 months postoperatively. Four eyes required YAG laser posterior capsulotomy. This particular trifocal combines both a bifocal and trifocal pattern on its posterior surface and maintains effective near intermediate and distance vision at 12 months and associated with good levels of contrast sensitivity and ocular aberrations.

Reference

Implantation of diffractive trifocal intraocular lens: One-year follow up.
P Mojzis, K Majerova, L Hrckova, DP Pinero.
JOURNAL CATARACT REFRACTIVE SURGERY
2015;41:1623-30.

JOURNAL PEDIATRIC OPHTHALMOLOGY STRABISMUS

Association of astigmatism and inferior oblique over action
Reviewed by: Fiona Rowe
Vol 22 no 6
 

The aim of this study was to evaluate the association between primary inferior oblique over action and astigmatism along the axis on the overacting muscle. The authors explored the postoperative change in axis of astigmatism and cylinder power in a retrospective study of 118 patients (mean age 11.31 ±10.59 years). Sixty subjects had no inferior oblique over action, 41 had bilateral inferior oblique over action and 17 had unilateral inferior oblique over action. The median over action was +3. Sixty-two percent of eyes had mild astigmatism <1D, 35% with moderate astigmatism of 1-3D and 3% with high astigmatism >3D. For those with no / mild astigmatism, postoperative there was significant median increase in with-the-rule cylinder power of 0.28D. Those with bilateral inferior oblique over action had significant increase of cylinder power along the 90 degree axis on -0.45D mean change. This was not observed in the unilateral over action group but analysis was limited by small numbers in this group. The results show that eyes with inferior oblique over action do not have increased prevalence of astigmatism postoperatively. 

Reference

Is inferior oblique over action associated with astigmatism?
Al-Haddad C, Antonios R, Khatib L, et al.
JOURNAL PEDIATRIC OPHTHALMOLOGY STRABISMUS
2015;52:288-93.

JOURNAL PEDIATRIC OPHTHALMOLOGY STRABISMUS

Ectopia lentis management
Reviewed by: Fiona Rowe
Vol 22 no 6
 

This review discusses the management of non-traumatic ectopia lentis in the paediatric population focussing on the variety of surgical options for these patients. The review considers visual sequelae and conservative management, limitations for surgery with respect to historical and current review, surgical approach with respect to the limbus, pars plana approaches plus anterior vitrectomy, visual rehabilitation with respect to anterior chamber IOL, iris-fixated posterior chamber IOL, scleral-fixated posterior chamber IOL and capsular tendon rings – the latter being most recently described in the literature with promising results. The authors conclude that visual rehabilitation and treatment of amblyopia are essential following surgical treatment of ectopia lentis. 

Reference

New management strategies for ectopia lentis.
Simon MA, Origlieri CA, Dinallo AM, et al.
JOURNAL PEDIATRIC OPHTHALMOLOGY STRABISMUS
2015;52:269-81.

JOURNAL PEDIATRIC OPHTHALMOLOGY STRABISMUS

High myopia macular thickness
Reviewed by: Fiona Rowe
Vol 22 no 6
 

The purpose of this study was to compare macular thickness and volume in 15 highly myopic (>-6D) young children with 11 age-matched controls (-2 to +4D refractive errors) using Stratus third generation OCT. Mean spherical equivalent was -9.42 ±2.81D for subjects and +0.89 ±1.78D for controls. Mean axial length was 26.45 ±0.86mm for subjects and 22.05 ±1.09mm for controls. Mean foveal thickness was 189.13um (thicker) for subjects compared to controls (159.88um). Macular thickness in all four quadrants in inner and outer macular areas were significantly thinner with myopia and smaller macular volumes. The authors conclude that anatomic changes in the retina occur even in small children with myopia. This may impact on considerations of OCT data when myopia is associated with other ocular conditions. 

Reference

Macular thickness in highly myopic children aged 3-7 years.
Ziylan S, Kiziloglu OY, Yenerel NM, et al.
JOURNAL PEDIATRIC OPHTHALMOLOGY STRABISMUS
2015;52:282-6.

JOURNAL PEDIATRIC OPHTHALMOLOGY STRABISMUS

Outcome of three to four muscle surgery for XT
Reviewed by: Fiona Rowe
Vol 22 no 6
 

This study evaluates the short-term outcomes of surgery involving three or four horizontal rectus muscles in patients with exotropia >40 prism dioptres. The authors evaluate the role of adjustable sutures and identify prognostic factors influencing surgical outcome. They assess the effect of postoperative drift in surgical success. Forty-seven patients were evaluated: 34 requiring three muscle surgery (mean angle 55 ±9.8PD and mean surgery of 22mm) and 13 requiring four muscle surgery (mean angle 72 ±8.8PD and mean surgery of 28mm). All were assessed at one week postoperatively and 12 were overcorrected. Eight eventually aligned, one became under corrected and three remained overcorrected. Higher preoperative angle appeared to predispose to under correction. Adjustable sutures were used in 18 cases: 11 in three muscle surgery and seven in four muscle surgery. There was no significant difference between traditional and adjustable sutures. Not all patients had two month follow-up assessments but of those that did, 77% had a mean drift of 10 ±8.8PD. Rates of successful alignment and overcorrection reduced whilst rates of under correction increased as the drift occurred. The study is limited by small numbers with complete follow-up data and lack of longer-term follow-up.

Reference

Three and four muscle horizontal muscle surgery for large angle exotropia.
Chen JH, Morrison DG, Donahue SP.
JOURNAL PEDIATRIC OPHTHALMOLOGY STRABISMUS
2015;52:305-10.

JOURNAL PEDIATRIC OPHTHALMOLOGY STRABISMUS

Syndromic V-pattern management
Reviewed by: Fiona Rowe
Vol 22 no 6
 

The authors document their experience in the management of four cases of Crouzon syndrome and review the anatomical extraocular muscle anomalies noted during surgery. Horizontal strabismus surgery varied in each of the four cases according to individual extraocular muscle abnormalities and usually required two or more procedures. Most cases required significant amounts of treatment, especially when abnormal development of extraocular muscles existed. Compared to normal muscles, the muscles in Crouzon syndrome have pathological changes consistent with collagen degeneration. The authors found the tendon capsule to be thicker than normal and, in some cases, the lateral rectus had fused to the sclera. They found inferior rectus muscle abnormalities to a greater extent than superior oblique. Treatment of amblyopia was important and they reported that, the better the visual acuity, the better the outcome.

Reference

Surgical treatment of V pattern exotropia in Crouzon syndrome.
Qiao T, Wang G, Xiong J, et al.
JOURNAL PEDIATRIC OPHTHALMOLOGY STRABISMUS
2015;52:299-304.

OCULAR IMMUNOLOGY AND INFLAMMATION

Intravitreal triamcinolone for uveitic macular oedema
Reviewed by: Saruban Pasu
Vol 22 no 6
 

This paper from South Korea reports on a prospective, double blind, randomised clinical study designed to evaluate the additional benefit of intravitreal triamcinolone (TA) administration for noninfectious uveitic macular oedema as an adjunct therapy to systemic anti-inflammatory treatment. Patients were randomised into two groups, the intravitreal TA injection group (TA group), and the sham group. Inclusion criteria specified CFT >300 microns or thicker than the 99th percentile of normal distribution in any of the parafoveal areas. Patients in the TA group were administered intravitreal TA (4 mg/0.1 ml). Systemic corticosteroids or immunosuppressants and topical corticosteroids were administered to patients in both groups under the same policy. The primary outcome measure was the change in retinal thickness measured by SD-OCT at monthly follow-up visits until six months. Fifty eyes met the inclusion criteria. The causes of uveitis were similar in both groups, with intermediate uveitis or pars planitis, Behcet’s disease and idiopathic posterior or panuveitis being the most frequent. In the TA group, the thickness of the central foveal area decreased significantly sooner than in the sham group. The parafoveal area thickness decreased more in the TA group than in the sham group at months two and three. The difference between the two groups was not significant after month four. The BCVA did not differ significantly between the two groups throughout the follow-up period and did not improve significantly from baseline in either group. The number of patients that showed decrease of leakage on FA to <1 disc diameter on their final visit was significantly greater in the TA group. The number of patients that were able to decrease systemic prednisolone to less than 10mg was significantly greater in the TA group. No patients required cataract surgery throughout the study period. When compared to baseline, the IOP was significantly increased at months one, two and three in the TA group. However, all cases with an IOP elevation above 22mmHg were controlled with medical therapy alone, and surgery was not required for IOP control in any case.

Reference

Intravitreal triamcinolone injection for uveitic macular edema: a randomized clinical study.
Shin JY, Yu HG.
OCULAR IMMUNOLOGY AND INFLAMMATION
2015;23(6):430-6.

OCULAR IMMUNOLOGY AND INFLAMMATION

Ozurdex use in noninfectious uveitis
Reviewed by: Saruban Pasu
Vol 22 no 6
 

Burkholder et al. reported the practice patterns of 45 respondents of approximately 176 surveyed members of the American Uveitis Society regarding the use of the Ozurdex implant. Most respondents performed the injection in either a procedure (41.0%) or clinic (23.1%) room, with just over one in five (20.5%) preferring an operating room. Over half (57.5%) used subconjunctival lidocaine as their primary anesthetic. The most frequent indication for injection was macular oedema (76.5%), whereas the most commonly associated diagnosis was pars planitis (24.7%), followed by multifocal choroiditis (18.8%), birdshot chorioretinitis (18.8%) and sarcoid associated uveitis (17.6%). The most commonly cited contraindication to injection was aphakia (62.2%) reflecting concern for anterior chamber migration of the implant with subsequent corneal decompensation. Other contraindications were glaucoma requiring more than two pressure lowering medications (54.0%), a history of corticosteroid-induced ocular hypertension (32.4%), and the presence of an anterior chamber intraocular lens (32.4%). Over one-third (37.7%) of respondents were of the opinion that the Ozurdex implant was effective for longer, whereas nearly three-quarters (71.4%) were of the opinion that the Ozurdex implant was less likely to cause corticosteroid induced ocular hypertension when compared with an anchored fluocinolone acetonide (FA) implant. Nearly half of all respondents (46.5%) preferred either a trial with at least one Ozurdex implant prior to placing an anchored FA implant, or using multiple DEX implants in place of an FA implant (48.8%). Nearly two-thirds (64.3%) responded that they did fewer anchored FA implants since the approval of Ozurdex implants. Additional long-term data are needed to better understand the risks and benefits of sequential Ozurdex implants. The authors noted the wide variability in practice patterns and the clearly perceived role for both the Ozurdex and FA implants in treating patients with chronic non-infectious uveitis.

Reference

The dexamethasone intravitreal implant for noninfectious uveitis: practice patterns among uveitis specialists.
Burkholder BM, Moradi A, Thorne JE, Dunn JP.
OCULAR IMMUNOLOGY AND INFLAMMATION 
2015;23(6):444-53.

OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY

Bupivicaine injection for Bell’s palsy
Reviewed by: James Hsuan
Vol 22 no 6
 

This study assesses the use of intramuscular bupivicaine to treat lid retraction and lagophthalmos in facial palsy. It is a prospective non-comparative interventional series of 10 patients with Bell’s palsy (House-Brackman grade IV or V) who each received three serial injections of 5ml of 0.75% bupivicaine. All patients had been diagnosed at least a year before treatment, and had previously shown some recovery. All had stable lid positions for six months and none had undergone prior lid surgery. The bupivicaine was injected into the upper and lower lid preseptal and pretarsal orbicularis oculi muscle and the pre-injection lid positions were compared with those at one, three and six months post-injection. They found a significant decrease in lagophthalmos from an average of 3.9mm pre-injection to 2.3mm at six months. The vertical palpebral aperture decreased significantly from 11.2mm to 9.4mm, with improvement in both upper and lower lid retraction. Similarly, corneal exposure and scleral show in shut eyes also improved significantly. There were no complications and all patients also reported a reduction of epiphora and foreign body sensation. The main weaknesses of the study are the small numbers and lack of longer-term follow-up or a control group. Given that bupivicaine causes myotoxicity which subsequently leads to regeneration, it would have been interesting to see if there was an initial worsening of the facial palsy parameters before the later improvement. Unfortunately the one and three month data are not provided. Despite these drawbacks this is an interesting and original pilot study with impressive results which merits further investigation.

Reference

Bupivicaine injection for management of lagophthalmos due to long-standing idiopathic facial nerve palsy.
Rajabi MT, Shadravan M, Mazloumi M, et al.
OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY 
2015;31:459-62.

OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY

Lacrimal gland carcinoma
Reviewed by: James Hsuan
Vol 22 no 6
 

This is a major review of the management of lacrimal gland carcinoma, focusing mainly on adenoid cystic carcinoma. Relevant literature published in English since 1970 was included amounting to some 40 articles after filtering. Overall mortality for all lacrimal gland carcinomas was estimated at 50% at five years. Adenoid cystic carcinoma was the most common lacrimal gland epithelial tumour, accounting for 62% of all carcinomas. The authors describe several unique features including a younger age at diagnosis, at least 10 years earlier than other carcinomas, and pain occurring more frequently and earlier in the disease. Survival rates between different carcinomas were hard to compare due to lack of standardisation in tumour staging, but adenoid cystic carcinoma characteristically had high local and distant recurrence rates, often after many years of dormancy. One series had 45% survival at five years, 23% at 10 and 14% at 15 years. Younger age carries a better prognosis, whereas solid, basaloid tumours fare worse than other histological sub-types. Up to 85% will have perineural invasion which is associated with a higher risk of local recurrence and skull base involvement. Bone invasion was found in 81% in a series from the Mayo clinic. Tumour size is a strong indicator of local recurrence and metastasis, with T3 or larger tumours having significantly worse outcomes. Treatment options remain controversial, in particular whether exenteration improves survival compared with local excision; although the authors suggest that local, globe sparing surgery should be explored further for small tumours. Adjuvant radiotherapy has a role as the tumours are more radio-sensitive than other lacrimal gland carcinomas. Chemotherapy seems less effective, both as adjunctive treatment and as neoadjuvant therapy. This is an interesting and comprehensive review which also benefits from the inclusion of a useful management algorithm for all lacrimal gland masses. 

Reference

Management of lacrimal gland carcinoma: Lessons from the literature in the past 40 years.
Woo KI, Yeom A, Esmaeli B.   
OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY
2016;32:1-10.

OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY

Lateral canthal position after lateral orbitotomy
Reviewed by: James Hsuan
Vol 22 no 6
 

This is a retrospective photographic study of changes in the lateral canthal position following a lateral orbitotomy performed via a lateral canthotomy and cantholysis of both upper and lower limbs of the lateral canthal tendon. Reconstruction of the lateral canthus was performed with a single 4-0 vicryl suture passed in a circular fashion through the periorbita, inferior crus and tarsal plate, superior tarsal plate and crus, then periorbita again. Forty-one operations were assessed including 34 decompressions for thyroid eye disease. The authors measured changes in the width of the horizontal palpebral aperture, the height of the lateral canthus relative to the medial canthus, and assessed rounding of the lateral canthal angle, relating these to changes in proptosis measured clinically. They found no significant change in the horizontal width of the palpebral aperture, although there was approximately 0.2mm of reduction for every 1mm of reduction in proptosis in the decompression cases. There was a 0.13mm rise in the lateral canthal vertical position relative to the medial canthus. There was no change in the canthal angle or rounding of the canthus. The study refutes anecdotal reports of lateral canthal dystopia following lateral orbitotomy involving a lateral canthal incision which have led to alternative surgical approaches. The authors recommend their technique, suggesting it provides good access with a simple closure and no significant complications. Although this is a retrospective study it provides reasonable evidence to commend this technique. One particular weakness is the assessment of rounding of the lateral canthus, which appears to be a subjective assessment rather than a true measurement. Given this is one of the potential major criticisms of the technique, which they are refuting, more formal data would have provided a stronger argument. 

Reference

Lateral canthal position following lateral orbitotomy and the influence of ocular proptosis.
Shams PN, Baker MS, Allen RC.
OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY
2016;32:53-7.

OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY

Recurrent thyroid eye disease
Reviewed by: James Hsuan
Vol 22 no 6
 

This study investigates the incidence of recurrent thyroid eye disease. The authors retrospectively reviewed the records of 415 patients who had been diagnosed with thyroid eye disease between 2006 and 2012. The medical notes were scrutinised for evidence of a previous episode of thyroid eye disease based on a history of prior treatment for thyroid eye disease or significant orbital inflammation. In addition old photographs and previous orbital imaging were reviewed if available. These findings were compared with the patient’s state at their first consultation in the authors’ institution to determine if they were stable or active at that stage. Using this method they retrospectively diagnosed recurrent disease in patients who had active disease at presentation and evidence of another episode of active disease in the past, or those who were stable but had evidence of two or more past active events. Using these criteria they deduced that 65 of the 415 patients had recurrent thyroid eye disease, a rate of 15.7%, much higher than the only other published figure of 5%. They found an average time interval between episodes of 10.3 years. Six patients had suffered multiple recurrences, and patients who were smokers during their first event were at increased risk of reactivation. Periocular surgery was also a risk for recurrence. The authors explain the higher rate was due to the other study including a recurrence only if it occurred after five years of stability, whereas they found 50.8% of recurrences occurred within five years. Although they describe a number of trigger factors, the strongest being periocular surgery, including cataract surgery, they do not compare the incidence of these triggers with patients who did not have a recurrence, casting uncertainty on whether these are genuine risk factors. The study has significant weaknesses in using retrospective analysis of patients’ histories and examinations, and there is conjecture in the discussion and interpretation of the trigger factors. Despite this, there is evidence here that the incidence of recurrent thyroid eye disease is higher than was previously thought. 

Reference

Recurrent thyroid eye disease.
Patel P, Khandji J, Kazim M.   
OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY 
2015;31:445-8. 

ORBIT

An unusual presentation of dysthyroid orbitopathy
Reviewed by: Konal Saha
Vol 22 no 6
 

The authors present a case of a 50-year-old male smoker who presented with bilateral gaze evoked amaurosis (GEA), i.e. the patient was aware of loss of vision in all gaze positions other than the primary position. The patient was being treated for thyrotoxicosis. A patient photo was interesting in that it did not show gross clinical signs of dysthyroid orbitopathy, however an MRI scan did show gross extraocular muscle enlargement. Clinical examination revealed optic disc swelling on both sides. The GEA was presumably caused by apical crowding exacerbated by extraocular movement. The patient’s symptoms were partially relieved with intravenous methylprednisolone and rituximab. 

Reference

Dysthyroid orbitopathy presenting with gaze-evoked amaurosis: case report and review of the literature.
Orlans HO, Bremner FD.
ORBIT
2015;34(6):324-6.

ORBIT

Bisphosphonates can cause orbital inflammation
Reviewed by: Konal Saha
Vol 22 no 6
 

The authors describe four patients with bisphosphonate induced orbital inflammation and review a further 25 cases in the literature. Intravenous zoledronate was the most common precipitant (76% of cases) with the mean time until onset of inflammation being three days (range one to 28 days). The orbital inflammation resolved in all but one patient with cessation of bisphosphonate treatment and commencement of steroid treatment. The exact nature of the steroid treatment was not described.

Reference

Bisphosphonate induced orbital inflammation: a case series and review.
Pirbhai A, Rajak SN, Goold LA, et al.
ORBIT
2015;34(6):331-5.

ORBIT

Localising the cause of bloody tears
Reviewed by: Konal Saha
Vol 22 no 6
 

The authors present two cases of ‘idiopathic’ bloody tearing. The paper presents the potential causes of bloody tearing, highlighting the difficulty that can be encountered in diagnosing and managing these patients. The authors use punctal plugs in these cases which may be useful in determining if the cause of the bloody tears is distal or proximal to the punctum. Interestingly both of the cases resolved without active intervention. 

Reference

Haemolacria: A novel approach to lesion localization.
Fowler BT, Kosko MG, Pegram TA, et al.
ORBIT
2015;34(6):309-13. 

STRABISMUS

BT outcome for CP and ET
Reviewed by: Fiona Rowe
Vol 22 no 6
 

The authors evaluate the clinical outcome of botulinum toxin (BT) injection in the correction of esotropia in 44 patients with cerebral palsy (CP). BT was injected under general anaesthesia without EMG guidance. Of the children, 47.7% were male and mean age was 47.56 ±30.86 months (5-124 months). There was no significant difference in outcome at 12 months for those with greater or less than 50 dioptres of esotropia at time of injection. Complications included subconjunctival haemorrhage (n=6) and ptosis (n=17). Success rate at one year was 68.18%. Rates of overcorrection and under correction were 43% and 6.8% respectively at one month, and 6.8% and 25% at one year. Lower age, ptosis, larger pre-injection deviation and less esotropia one month post injection may be predictive factors for achieving better results. The authors conclude that BT is a reasonably less invasive and scar-free procedure for the early management of these children, allowing more surgical options for later management as required. 

Reference

Clinical outcomes of botulinum toxin injection in patients with cerebral palsy and esotropia. 
Ameri A, Mirmohammadsadeghi A, Makateb A, et al.
STRABISMUS 
2015;23:8-13. 

Cataract & Refractive

Association between serum 25-hydroxyvitamin D levels and age-related cataracts
Reviewed by: Sharmina Khan
Vol 22 No5
 

Cataractogenesis occurs as a result of ageing, smoking, exposure to UV radiation and genetic predisposition. Antioxidants can reduce the cataract risk as found in animal models and humans and vitamin D is one of them. This epidemiological study based in South Korea looked at cataract formation and serum vitamin D levels. Study data was obtained from Korean National Health and Nutrition Examination Survey. Exclusion criteria were aged 39 years or younger, no serum Vitamin D levels measured and no slit-lamp examination. Cataracts were graded according to the internationally well-established Lens Opacities Classification Systems III (LOCS III) for assessment. Cataracts were graded as cortical, nuclear, anterior subcapsular, posterior subcapsular, or mixed type. Age-related cataracts were defined as one or more types. Vitamin D levels in the serum were collected after eight hours of fasting and measured with radioimmunoassay. Sunlight exposure was categorised above or below five hours per day. Systemic medical history was also considered. They found that in 9479 men significantly lower cataract prevalence (24% lower) was associated with higher levels (highest quintile) of serum vitamin D compared to the lowest levels of serum vitamin D (lowest quintile), after adjustment for potentially confounding factors. Biologically this is explained by vitamin D inhibiting oxidation of proteins in the lens that is a key step in cataractogenesis. This study doesn’t look at associated intraocular, i.e. aqueous humour levels of vitamin D and see whether that correlates with serum levels. It only hypothesises why vitamin D levels are lower in women e.g. because fewer hours are spent exposed to daylight sun required by the skin to produce vitamin D. Does the cataract protective effect of vitamin D outweigh the cataractogenic effect of UV light exposure? There is no genetic analysis on vitamin D receptor gene known to have frequent polymorphisms. This is yet another study suggesting that increasing intake of dietary supplements may prevent cataract formation.

Reference

Association between serum 25-hydroxyvitamin D levels and age-related cataracts.
D Jee, EC Kim.
JOURNAL CATARACT REFRACTIVE SURGERY
2015;41:1705-15.

Association between serum 25-hydroxyvitamin D levels and age-related cataracts.

D Jee, EC Kim.

JOURNAL CATARACT REFRACTIVE SURGERY

2015;41:1705-15.

Cataract & Refractive

Incidence and risk factors of late in the bag intraocular lens dislocation
Reviewed by: Sharmina Khan
Vol 22 No5
 

The aim of this study was to identify risk factors for late in the bag dislocation over a 21 year period. Worldwide the incidence varies from 0.05% to 3.0%. In this Swedish study they report an increase in incidence in late in the bag IOL dislocation. US studies haven’t shown any increase whereas an Australian study has shown an increase in late dislocation rates. A well known Norwegian study shows increased dislocation rates in those with pseudo-exfoliation found in higher prevalence in Scandinavian countries. Risk factor for late IOL dislocation are pseudoexfoliation glaucoma (PXF), previous vitrectomy, long axial length (>26.0mm), uveitis, connective tissue disorders, retinitis pigmentosa, glaucoma and zonular dehiscence during cataract surgery. The study identifies factors other than PXF. The data is based on 140 eyes of 123 patients compared with one case-control that didn’t have an IOL dislocation. There was a five-fold increase in the number of patients having cataract surgery performed and the pseudophakic population tripled. The median duration of pseudophakia (time from surgery to time of dislocation) increased by four years which contributed to the rising number of late IOL dislocations. The cumulative risk for IOL dislocation was 0.55% and the risk greater for those operated in the decade between 2002 and 2012 than 1992 and 2001. This is thought to be due to greater numbers of more difficult cataract extractions being completed with phakoemulsification than ever before. There was no difference in age between the study and control groups. Longer phakoemulsification time was associated with late IOL dislocation. There was no quantitative data on cataract morphology to try and correlate this with late dislocation rates. The frequency of capsular tension ring insertion was much higher in the dislocated group versus the control. 

Reference

 

Incidence and risk factors of late in the bag intraocular lens dislocation: Evaluation of 140 eyes between 1992 and 2012.
Dabrowska-Kloda K, Kloda T, Boudiaf S, et al.
JOURNAL OF CATARCT AND REFRACTIVE SURGERY
2015;41:1376-82

 

Incidence and risk factors of late in the bag intraocular lens dislocation: Evaluation of 140 eyes between 1992 and 2012.

Dabrowska-Kloda K, Kloda T, Boudiaf S, et al.

JOURNAL OF CATARCT AND REFRACTIVE SURGERY

2015;41:1376-82

Cataract & Refractive

Prophylaxis for clinical macular oedema after phacoemulsification
Reviewed by: Brian Ang
Vol 22 No5
 

The authors report on a retrospective cohort study looking at three different prophylaxis methods for macular oedema after cataract surgery: 1) Topical prednisolone acetate (PA) alone; 2) Topical PA in combination with non-steroidal anti-inflammatory drug (NSAID); 3) Intraoperative subconjunctival injection of 2mg triamcinolone acetonide (TA). Inclusion criteria were reduced vision to 6/12 or worse and evidence of macular oedema on optical coherence tomography (OCT) five to 120 days after cataract surgery. The incidence of macular oedema was 0.73% (118 cases out of 16,070 cataract procedures). The authors found that PA in combination NSAID worked best at reducing the risk of macular oedema after surgery. Intraocular pressure spikes were not statistically significantly different among all three groups. Interesting results, but this requires additional research particularly in stratifying risk levels among cataract surgery patients.

Reference

Comparative effectiveness of three prophylactic strategies to prevent clinical macular edema after phacoemulsification surgery.
Shorstein NH, Liu L, Waxman MD, et al.
OPTHALMOLOGY
2015;122:2450-6.

Cornea & External Eye Disease

Confocal microscopy and corneal graft rejection
Reviewed by: Magdalena Popiela
Vol 22 No5
 

Forty-five patients following penetrating keratoplasty (PK) were examined with the HRT III Rostock Cornea Module confocal microscope at various points after their surgery for two years. Activated keratocytes (AKs) were counted manually and their mean number evaluated. A pattern was noted where AKs number decreased steadily and stabilised by four months after PK in 39 patients without graft rejection. At one year, when post op steroid regimen was discontinued, there was a slight but significant increase in their number followed by continuing decline. During the first four months there were no significant differences in mean AKs counts between patients with and without graft rejection. In the six patients with graft rejection, the mean AK count was significantly higher than in patients without rejection, two months before, one month before, and at the rejection diagnosis. A pattern of increasing number of AKs starting at least two months prior to clinically visible rejection was noted. Although this study has a small sample and AK were counted manually, it proposes in vivo confocal microscopy as a useful tool in predicting graft rejection. Further study is needed to evaluate if increasing steroidal therapy in the setting of increasing AKs would prevent clinical graft rejection. 

Reference

Predicting corneal graft rejection by confocal microscopy.
Kocaba V, Colica C, Rabilloud M, Burillon C. 
CORNEA
2015;34(10):61-4

Cornea & External Eye Disease

DALK as an early therapeutic option for Acanthamoeba keratitis
Reviewed by: Brian Ang
Vol 22 No5
 

Eleven patients with Acanthamoeba keratitis (AK) were treated by early therapeutic deep anterior lamellar keratoplasty (DALK). All surgeries were performed in patients who had no response to standard medical therapy of chlorhexidine gluconate, propamidine isethionate and neomycin sulphate, within 10-15 days of starting the medical therapy and within 30 to 60 days from the onset of symptoms. All patients had visually disabling ulcers within a central optical zone of 6mm. There were no graft rejections or recurrences of AK with follow-up of 24.8 +/- 9.6 months. The only postoperative complication of delayed epithelialisation, a result of the use of anti-acanthamoebic topical drops, has been successfully managed by eye patching, with epithelium healing within 15 days. This small case series describes an interesting approach that seems to be more successful in terms of reduced graft rejections and operative risks compared to penetrating keratoplasty performed late in the disease course. Although this case series is small, early therapeutic DALK can be considered in patients affected by visually disabling central AK and no response to medical therapy. The rationales to treat surgically so promptly are to eradicate medically unresponsive infection and visually rehabilitate patients, who would have required a corneal graft at a later stage.

Reference

Early deep anterior lamellar keratoplasty (DALK) for Acanthamoeba keratitis poorly responsive to medical treatment. 
Sarnicola E, Sarnicola C, Sabatino F, et al.
CORNEA
2016;35(1):1-5.

Cornea & External Eye Disease

Familial Mediterranean Fever and keratoconus
Reviewed by: Magdalena Popiela
Vol 22 No5
 

This retrospective case control study was conducted in the Genetic Diagnostic Centre in Turkey. It examined the prevalence of keratoconus in two groups; patients with Familial Mediterranean Fever (FMF) and age matched controls free of FMF, who were tested for other genetic disorders in the same time period and living in the same regions. Four patients out of 100 with FMF were identified to have keratoconus, whereas no patients in a control sample of 300 had keratoconus. This difference was statistically significant. The 4% keratoconus prevalence in the FMF group was also statistically higher than the highest keratoconus prevalence reported in the literature. Patients who have FMF with a homozygous mutation of the Familial Mediterranean Fever (MEFV) gene seem to be most at risk of having keratoconus. The authors report the newly found association of keratoconus and FMF, linking both diseases to defects in MEFV gene. This results in exaggerated pro-inflammatory actions of interleukin 1B and might be an important factor in the development of keratoconus in patients with FMF. Further studies are warranted to confirm the genetic basis for this newly found association.

Reference

Association between keratoconus and Familial Mediterranean Fever in Turkey. 
Kosker M, Arslan N, Alp MY, et al.
CORNEA 
2016;35(1):77-80

Cornea & External Eye Disease

How to achieve 1% solution of Lissamine green
Reviewed by: Magdalena Popiela
Vol 22 No5
 

Lissamine green (LG) concentration of 1% is clinically effective in the diagnosis of ocular surface disease. LG is now commercially available only in a form of dye-impregnated strips, whose concentration is insufficient. This study examined how to achieve 1% concentration of LG using commercially available strips. It showed that dipping one LG strip in one drop of various diluents achieved concentrations around 0.2%. Two methods giving rise to LG concentration of 1% are as follows: incubating two LG strips in 200µL (four drops) of preservative free artificial tears (PFAT) for five minutes or four LG strips in 200µL of PFAT for one minute. Cost analysis showed that the first method costs $0.67 (circa 44 pence) and the second $1.27 (circa 83 pence). Both identified methods are easy and cost-effective to perform in clinic to achieve desired concentration of LG. 

Reference

Obtaining Lissamine green 1% solution for clinical use.
Stock M, Salvay D, Shoss B, et al. 
CORNEA
2015;34(11):1523-5.

Cornea & External Eye Disease

Surgical complications of ReLEx
Reviewed by: Magdalena Popiela
Vol 22 No5
 

Femtosecond laser refractive lenticule extraction (ReLEx) is a novel procedure for treatment of myopia and myopic astigmatism, which eliminates the use of microkeratome and excimer laser. Currently there are two techniques: FLEx – femtosecond lenticule extraction (similar to conventional LASIK) and SMILE – small incision lenticule extraction, where no flap is created. This article describes surgical complications of both techniques in a retrospective review. In the FLEx group 18.3% of patients suffered intraoperative complications: suction loss, black spots (resulting in incomplete cleaving surface), bubbles in the interface, and lenticule misdissection. In the SMILE group 26.9% of patients experienced complications: epithelial defect, suction loss, opaque bubble layer, cap rupture, and lenticule rupture. Most of the reported problems were thought to be due to surgeons’ learning curve with no unfavourable long-term effects over mean follow-up of 36 months. Black spots and bubbles in the interface were classed as mild complications with no lasting effects on vision, however, the actual visual acuities or other long-term sequels were not reported. ReLEx procedures are gaining popularity as they have certain advantages over conventional LASIK. However, they carry a set of unique complications, resulting from femtosecond laser’s mode of action, and their initial learning curve has high intraoperative complications.

Reference

Refractive lenticule extraction complications.
Ramirez-Miranda A, Ramirez-Luquin T, Navas A, Graue-Hernandez E.
CORNEA
2015;34(10):65-7
.

Glaucoma

Anterior segment OCT predicts gonioscopic angle closure
Reviewed by: Brian Ang
Vol 22 No5
 

This is a prospective observational study of 342 subjects over four years. Sixty-five were controls who had open angles both on gonioscopy and AS-OCT, while 277 had open angles only on gonioscopy but iridotrabecular contact (ITC) on AS-OCT (one to four quadrants). At the end of the four year study period, 27.4% of those with ITC on AS-OCT at baseline developed gonioscopic angle closure in two or more quadrants, in contrast to none in the control subjects. The greater the amount of ITC on AS-OCT, the higher the likelihood of gonioscopic angle closure occurring after four years. This study confirms what many angle closure glaucoma specialists have long suspected – AS-OCT detects angle closure earlier than gonioscopy and will play an increasingly important role in the management of angle closure suspect patients. 

Reference

Anterior segment imaging predicts incident gonioscopic angle closure.
Baskaran M, Iver JV, Narayanaswamy AK, et al.
OPTHALMOLOGY 
2015;122:2380-4

Neuro-Ophthalmology

A case report of bidirectional aberrant upward eye movement
Reviewed by: Claire Howard
Vol 22 No5
 

The authors present a case report of a 14-year-old boy with left ptosis and strabismus since childhood. In primary position he had left hypotropia with ptosis. On elevation of the right eye, the left eye depresses and adducts. Conversely, on depression of the right eye, the left eye elevates and abducts. This case is bidirectional, unlike the unidirectional cases of synergistic divergence described in the literature previously.  This bidirectional aberrant upward movement cannot be explained by rectus muscle co-contraction. In this case, the two vertical rectus muscles show reciprocal misinnervation, or it is possible that the effect is caused by co-contraction of one of the oblique muscles. 

Reference

Bidirectional synergistic vergence.
Gokce G, Ozgonul C, Cagatay HH, et al.
NEURO-OPHTHALMOLOGY
2015;39(5):234-5.

Neuro-Ophthalmology

A novel computerised portable pupillometer detects and quantifies relative afferent pupillary defect
Reviewed by: Jonathan C P Roos
Vol 22 No5
 

We have all had referrals from A&E telling us that a patient can’t see out of one eye. Sleepily we may ask “Is there an relative afferent pupillary defect (RAPD)?” to evaluate the seriousness of the presentation. The response is often flustered or surprised. “The pupils are fine” or something like that, but it is evident the referrer does not really know what an RAPD is or why it is useful. And lacking the requisite experience, they cannot then be asked to assess it either. All this may now be about to change thanks to Dr Volpe’s group which has developed an automated portable pupilometer to assess for and quantify RAPD. The machine assessed constriction amplitude, velocity and onset latency in 32 patients and 31 normal subjects who were stimulated with maximal light in one eye and reduced light in the other to mimic an afferent defect. The results showed a strong correlation between an expert examiner and the device, and the latter differentiated between patients with significant RAPD and controls with a high degree of accuracy (91%) in terms of both sensitivity and specificity. Amplitude and velocity were found to be more helpful than latency of onset of pupil constriction. The study unfortunately had some easily avoidable confounders: the patients ages ranged from 27-89 whilst the healthy volunteers were aged 21-34. In addition to being able to follow patients up in the long-term to assess for recovery in, for instance, typical optic neuritis, just like an ECG machine can help alert a technician to an abnormality requiring further assessment, likewise this machine may be used by frontline staff to help health care providers detect significant pathologies requiring urgent management.

Reference

A novel computerized portable pupillometer detects and quantifies relative afferent pupillary defect.
Cohen LM, Rosenberg MA, Tanna AP, Volpe NJ.   
CURRENT EYE RESEARCH
2015;40(11):1120-7
.

Neuro-Ophthalmology

A rare case of ophthalmic complications following allergic fungal sinusitis
Reviewed by: Claire Howard
Vol 22 No5
 

The authors present an unusual case report of a 32-year-old man with advanced allergic fungal sinusitis, presenting with severe bilateral visual loss and restricted ocular motility. On presentation he had an 18 month history of progressive nasal obstruction, as well as several months of diminished visual acuity. On examination he had counting fingers vision in his right eye and 6/9 in the left. He had proptosis of 27mm in the right eye and 25mm in the left. Eye movements were restricted bilaterally. Humphrey visual fields revealed globally depressed fields in the right eye and a temporal hemianopia with paracentral nasal scotomas in the left eye. This patient was treated with prednisolone as well as sinus surgery and as a result he showed improvements in his visual acuity, ocular motility and visual fields. Ophthalmic manifestations from this disease are rare but can occur in advanced disease and allergic fungal sinusitis must therefore be considered as a diagnosis by ophthalmologists. In such cases, early recognition, neuroimaging for optic nerve involvement and prompt ENT interventions are crucial to reduce visual loss. 

Reference

Compressive optic neuropathy from allergic fungal sinusitis.
Tong J, Jefferson N, Chaganti J, Fraser CL.
NEURO-OPHTHALMOLOGY
2015;39(5):236-9

Neuro-Ophthalmology

Amiodarone-associated optic neuropathy
Reviewed by: Brian Ang
Vol 22 No5
 

This is a retrospective population-based cohort study to evaluate the risk of developing optic neuropathy from the use of amiodarone in Taiwan. Over a five-year period (2005-2009), there were 6175 amiodarone-treated patients with 24,700 patients taken as controls. After a mean follow-up period of 688 days, optic neuropathy developed in 17 amiodarone patients (0.3%) and 30 control patients (0.1%) – this is statistically significant. Interestingly the risk is not increased with greater daily dose. However, male gender and longer duration were risk factors. Although amiodarone demonstrates a statistically significant greater risk of developing optic neuropathy compared to controls, the low incidence of 0.3% and lack of treatment options mean that screening is likely to be cost-ineffective. 

Reference

Amiodarone-associated optic neuropathy – a nationwide study.
Cheng HC, Yeh JH, Huang N, et al.
OPTHALMOLOGY 
2015;122:2553-9

Neuro-Ophthalmology

Placement of an eyelid weight as an upper lid spacer for lagophthalmos
Reviewed by: Anjali Gupta
Vol 22 No5
 

Upper lid loading with a weight is a well described procedure for the treatment of lagophthalmos and exposure keratopathy. The authors describe a modification of this procedure whereby the levator aponeurosis is recessed in combination with supratarsal weight implantation. The implant becomes a ‘spacer’ between the recessed levator aponeurosis and tarsus. It addresses both lagophthalmos and eyelid retraction caused by weakened orbicularis tone, in addition to addressing the visible and palpable weight contour with pretarsal placement. A retrospective case review was performed on consecutive patients undergoing this procedure modification with gold or platinum weights to assess outcomes. Sixteen eyelids of 14 patients were included in the study. Some of the included patients had concomitant procedures: lower lid tightening +/- mid face lift (six eyelids), direct brow lift (three eyelids) and lateral tarsorrhaphy (two eyelids). The average change in lagophthalmos was -3.5mm (SD 1.8) and the average change in MRD1 was -1.2mm (SD 1.3). Both these results were significant. One eyelid required revision. No patients had infection, implant migration or extrusion, with an average of 11.5 months follow-up. 

Reference

Placement of an eyelid weight as an upper lid spacer for lagophthalmos.
Mokhtarzadeh A, Lee EW, Barahimi BI, et al.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2015;43:766-8

Oculoplastic & Orbit

A case report of papilloedema caused by unilateral jugular vein thrombosis
Reviewed by: Claire Howard
Vol 22 No5
 

In rare cases, unilateral jugular vein thrombosis can lead to increased intracranial pressure and papilloedema, resulting in headaches and visual loss. The authors describe the case of a 45-year-old patient with squamous cell carcinoma of the larynx who developed right jugular vein thrombosis following chemoradiation therapy. The patient later went on to develop the complications of intracranial hypertension and papilloedema. The authors discuss the normal cerebral venous drainage, the potential role of chemoradiation therapy on the aetiology of jugular vein thrombosis and the mechanism of increased intracranial pressure secondary to unilateral jugular vein occlusion. This case highlights the need to consider increased intracranial pressure as a diagnosis in a patient presenting with headache and papilloedema, even if the papilloedema is only unilateral and one jugular vein is still patent. A prompt diagnosis and treatment can have a positive impact on the visual outcome. 

Reference

Papilloedema and increased intracranial pressure as a result of unilateral jugular vein thrombosis.
Thandra A, Jun B, Chuguilin M.
NEURO-OPHTHALMOLOGY
2015;39(4):179-82

Oculoplastic & Orbit

Comparison of central laminar thickness in optic neuropathy and normal eyes
Reviewed by: Claire Howard
Vol 22 No5
 

The study compares central laminar thickness (LT) among patients with glaucomatous optic neuropathy (GON), patients with non-GON and normal subjects. The non-GON group comprised eyes with demyelinating optic neuropathy (ON), anterior ischaemic ON, compressive ON, Leber hereditary ON and traumatic ON. LT was measured using enhanced-depth imaging optical coherence tomography (EDI-OCT). Results showed that LT measurements of GON and non-GON group eyes were thinner than those of control group eyes. In addition, LT of GON group eyes were thinner than those of non-GON group eyes. In the GON group, LTs were thinner in more severely affected eyes. In conclusion, the study results show that EDI-OCT is valuable for documenting structural abnormalities in optic neuropathy. The authors acknowledge that further studies are required to determine the role of OCT in detecting progression of ONs of various types. 

Reference

Enhanced depth imaging of central laminar thickness in optic neuropathy: comparison with normal eyes.
Thitiwichienlert S, Ishikawa H, Asakawa K, et al.
NEURO-OPHTHALMOLOGY
2015;39(4):166-74.

Oculoplastic & Orbit

Light reflex in preterm infants
Reviewed by: Claire Howard
Vol 22 No5
 

In this study, the pupillary size and light reflex was examined in premature infants using infrared video-pupillography and stimuli of red and blue light. Only eyes of infants without retinopathy of prematurity were included in the study. Pupillary light reflexes were obtained in response to 470nm blue and 635nm red stimuli with varying intensities. Red stimuli did not evoke a pupillary response in premature infants. Blue stimuli did produce a pupillary reflex and the extent of the reaction was dependent on the intensity of the stimulus. The results suggest that, in premature infants, the origin of the light reflex may be mediated predominantly by melanopsin-containing retinal ganglion cells. Preterm babies do not have fully functioning retinas. This study suggests that only the primitive non-image-forming system is operational, and the more sophisticated rod / cone system develops during later postnatal periods. 

Reference

Pupillary size and light reflex in premature infants.
Ikeda T, Ishikawa H, Shimizu K, et al.
NEURO-OPHTHALMOLOGY
2015;39(4):175-8

Oculoplastic and Orbit

Interesting causes and consequences of orbital inflammations
Reviewed by:
Vol 22 No5
 

Three articles discuss various causes and consequences or orbital cellulitis. The first highlights the possibility of orbital cellulitis causing cavernous sinus thrombosis and in the case presented progression to internal carotid artery aneurysm. The authors highlight the importance of considering cavernous sinus thrombosis when unilateral orbital signs become bilateral in the context of orbital cellulitis. The second paper describes a case of orbital inflammation nine days following hydrogel scleral buckle removal. The authors use magnetic resonance spectroscopy to aid diagnosis – ruling out suppurative and neoplastic causes. The inflammation is proposed to have occurred secondary to release of fragments of the hydrogel buckle into the orbit. The third paper describes a case of orbital cellulitis secondary to a dental abscess. The authors describe the polymicrobial nature of the infection and, hence, the need for broad spectrum antibiotic cover and possible dental extraction. 

Reference

Intracranial infectious aneurysm in orbital cellulitis.
Lee B, Kim C, Carrasco J.
ORBIT
2015;34(4):175-8.
Masquerading orbital abscess following attempted hydrogel scleral buckle removal: diagnostic value of orbital magnetic resonance spectroscopy.
Pakdel F, Hadizadeh H, Pirmarzdashty N, Kiavash V.
ORBIT
2015;34(4):179-82.
Orbital cellulitis of odontogenic origin.
Yan W, Chakrabarti R, Choong J, Hardy T.
ORBIT
2015;34(4):183-5.

Oculoplastic and Orbit

Prostaglandin-associated periorbitopathy
Reviewed by: James Hsuan
Vol 22 No5
 

This is a masked study of 33 patients who had been taking a prostaglandin analogue in one eye only for at least a year, to look for signs of prostaglandin-associated periorbitopathy (PAP). The investigators devised a new grading system to quantify the degree of fat atrophy and superior sulcus deformity, as well as taking exophthalmometry and margin reflex distance measurements.  All patients were assessed by three masked observers. There were equal numbers of patients on bimataprost, travaprost and latanaprost. Treated eyes had significantly more superior sulcus deformity, upper lid retraction, lagophthalmos and lid redness than untreated eyes. They also had more enophthalmos, lower lid retraction and higher skin creases but these were not statistically significant. Interestingly very few patients noticed or complained about the changes, and the difference in PAP grade between treated and untreated eyes increased significantly with age but not with duration of prostaglandin analogue use. Some parameters were significantly worse in those on bimataprost compared with latanaprost or travaprost. The authors noted that contrary to most previous reports of PAP, the syndrome induces lid retraction rather than ptosis. Although 15% of the treated eyes did have ptosis, other causes for this were found in every patient including large superior blebs, pre-existing ptosis or cataract surgery-induced ptosis. The mechanism behind PAP remains obscure. 

Reference

Unilateral prostaglandin-associated periorbitopathy: a syndrome involving upper eyelid retraction distinguishable from the aging sunken eyelid.
OPHTALMIC PLASTIC AND RECONSTRUCTIVE SURGERY
2015;31:373-8.
Rabinowitz MP, Katz LJ, Moster MR, et al.

Oculoplastic and Orbit

Repeated orbital decompression surgery
Reviewed by: James Hsuan
Vol 22 No5
 

This is a retrospective review of nine redo orbital decompressions in six patients. All operations were performed for dysthyroid optic neuropathy, both initially and when repeated. The interval between first and redo decompressions varied from one to 15 years and all patients were euthyroid at the time of further surgery although three were smokers. Three patients had a clinical activity score (CAS) of four or above. Eight out of nine eyes had decreased acuity, four had reduced colour vision and one had an afferent pupillary defect. All patients had field loss. Following repeat decompression, there was significant improvement in all these parameters in affected patients.  Proptosis reduced on average by 3mm. The authors stress the importance of adequate apical decompression, in particular removing the posterior medial wall and the orbital plate of the palatine bone. They noted that scarring from previous surgery, loss of anatomical landmarks and bleeding made the redo operations technically more difficult. The aetiology of late dysthyroid optic neuropathy is discussed. Significant reactivation of inflammation seems to be doubtful given the low CAS scores in at least half the patients. The authors suggest that low grade smouldering disease possibly combined with an orbital apex syndrome with congestion may be the mechanism. The study is limited by having small numbers, but is a useful warning to be aware of late compressive optic neuropathy in these patients without a frank reactivation of their inflammatory thyroid eye disease. 

Reference

Compressive optic neuropathy and repeat orbital decompression: a case series.
Kauh CY, Gupta S, Douglas RS, et al.
OPHTALMIC PLASTIC AND RECONSTRUCTIVE SURGERY
2015;31:385-90.

Ophthalmology

25-gauge PPV for retained lens fragments
Reviewed by: Sofia Rokerya
Vol 22 No5
 

This was a retrospective study including 40 eyes of 40 patients with mean age of 78 years, 19 females and 21 males, who underwent 25-gauge pars plana vitrectomy (PPV) for retained lens fragments with a minimum of six months of postoperative follow-up. PPV was performed within seven days after complicated cataract extraction in 24 cases (early) and 16 eyes after >7 days (late vitrectomy).The amount of dislocated nuclear material was graded by the surgeon intraoperatively, and the patients were divided into two groups according to the nuclear grading: group A (≤50% dropped nucleus) and group B (>50% dropped nucleus). The presence of brunescent nuclear pieces was considered. All patients were operated by a single vitreoretinal surgeon using the same PPV technique. The outcomes measured included best-corrected visual acuity (BCVA) and postoperative complications such as retinal detachment, cystoid macular oedema (CMO) and postoperative ocular hypertension or hypotonia. In early vitrectomy group all patients, except two, underwent PPV in the same setting of cataract extraction (mean interval 0.63 ± 2.2 days; range 0-7). In the late vitrectomy group, the mean interval between cataract extraction and PPV was 12.0 ± 3.1 days. There was no statistically significant difference in the grade of retained lens material between patients undergoing early and late PPV. The mean surgical vitrectomy time was 35.4 ± 16.9 min, ranging from 13 to 75 min. At six months of follow-up, the mean BCVA improved to 20/32 (logMAR = 0.23 ± 0.3), with no differences in terms of BCVA between patients with early or late PPV. At six months, the mean IOP was 17.1 ± 4.6mmHg, with no statistically significant difference between patients undergoing early or late PPV (17.0 ± 4.6 and 17.3 ± 4.5mmHg, respectively; p=0.78, two-tailed t test). There was no statistically significant correlation between the final postoperative IOP and the nucleus grade (p=0.79). During the follow-up, a rhegmatogenous retinal detachment occurred in four patients (10%). In all cases, the retinal detachment occurred in the late postoperative period, between three and five months after PPV. Retinal detachment occurred only in patients of group B, with two patients having grade 3, and two patients having grade 4 of retained nuclear material, and this difference was found to be statistically significant (p<0.002, two-tailed t test). Four patients with late PPV developed postoperative CMO, with no case of CMO among patients with early vitrectomy (p=0.014). CMO resolved with topical and systemic indomethacin (50mg/day). Although 25-gauge PPV proved effective irrespective of nuclear grading, when analysing surgical times a significant positive correlation was found between nuclear grade and duration of the PPV.  In case of retained nuclear fragments ≤50% (grades 0-2), the mean surgical time was 26.5 min, whereas when dislocated nuclear material was >50% (grades 3-4), surgery became considerably longer (mean time 56.2 min), questioning the actual convenience of the 25-gauge approach for the management of higher amounts of retained lens material. Limitations of the study include its retrospective and single surgeon nature, small sample size, the lack of lens material density grading and the lack of comparison with 20- and 23-gauge PPV groups. 

Reference

25-gauge pars plana vitrectomy for retained lens fragments in complicated cataract surgery.
Scupola A, Abed E, Sammarco MG, et al.
OPHTHALMOLOGICA 
2015;234:101-8.

Ophthalmology

Systemic anti-inflammatory versus fluocinolone
Reviewed by: Brian Ang
Vol 22 No5
 

In the Multicenter Uveitis Steroid Treatment (MUST) trial, 255 patients with intermediate uveitis, posterior uveitis or panuveitis were randomised to either fluocinolone acetonide intraocular implant or systemic corticosteroid therapy which was supplemented with immunosuppression if required. Patients were followed up for 54 months. Visual outcomes were similar in both groups at 54 months. However, the implant was better at controlling inflammation at every time point. Macular oedema improved significantly initially following implant insertion, but over time (36 months), the systemic group achieved similar improvements. It is therefore reasonable to consider the implant for unilateral cases and systemic therapy for bilateral cases.

Reference

Benefits of systemic anti-inflammatory therapy versus fluocinolone acetonide intraocular implant for intermediate uveitis, posterior uveitis, and panuveitis. Fifty-four-month results of the Multicentre Uveitis Steroid Treatment (MUST) Trial and follow-up study.
Multicenter Uveitis Steroid Treatment (MUST) Trial Research Group.
OPHTHALMOLOGY
2015;122:1967-75.

Paediatric Ophthalmology & Strabismology

Axial length in congenital ptosis
Reviewed by: Fiona Rowe
Vol 22 No5
 

The axial length in patients with unilateral congenital ptosis was prospectively examined in this study and lengths compared to fellow eyes. Thirty-seven patients included 24 male and 13 females with mean age of 17.8 ±16.3 years. Right ptosis was present in 15 and left ptosis in 22 cases. There was no significant difference in mean axial lengths between ptotic and fellow eyes. Only two patients (both adults) showed axial length differences of >0.67mm.Mean cylinder power was larger on the ptosis side than fellow eye but there was no significant difference for spherical power. The authors conclude that congenital ptosis may have little impact on axial length and the risk of axial myopia induced anisometropic amblyopia is low in unilateral congenital ptosis.

Reference

Axial globe length in congenital ptosis.
Takahashi Y, Kang H, Kakizaki H.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:177-82

Paediatric Ophthalmology & Strabismology

Change in infantile exotropia
Reviewed by: Fiona Rowe
Vol 22 No5
 

This study investigated the clinical course of patients with infantile exotropia who initially presented with a small exo deviation of 10-18 prism dioptres. Eighty-six patients were reviewed: 35 with follow-up of >2 years without surgery and 51 with surgery. The mean first distance angle was -15.4 ±2.3PD. Non-surgical treatment included part-time occlusion, glasses and alternate day occlusion. Over follow-up the mean angle increased to -18 ±5.6PD. Tendency for increased exo deviation was more prominent than that of reducing exo deviation. Impaired initial stereo acuity may be a potential predisposing factor for exo progression. Those with constant versus intermittent distance deviation were more likely to progress to surgery. Nearly half of the children increased to >20PD.

Reference

The clinical course of infantile exotropia with small initial deviation.
Lee BJ, Kim S-J, Yu YS.
JOURNAL PEDIATRIC OPHTHALMIC STRABISMUS
2015;52:206-12.

Paediatric Ophthalmology & Strabismology

GA vs. office measures of axial length
Reviewed by: Fiona Rowe
Vol 22 No5
 

Axial lengths were compared in an office setting versus under general anaesthetic (GA) to determine if awake office measures are feasible and whether differences in measures occur in both settings. The study included 33 eyes of 19 children; 84% male, 73% of eyes with cataract and 27% with clear lens. Average age was nine months (1-28). Two children were excluded where measures were not possible or there was too long a delay between the two measures. Average axial length was shorter by 0.12mm in office than GA measures: 18.88 versus 19.00mm which was not significant. There were no adverse during any measurement. Lens status and value measurement in the office setting was found to be significant with measurements tending to be larger for longer eyes. The authors conclude that measurements are feasible in most cases. They acknowledge the limitations of the study in relation to homogeneously white children, measures were not blinded and there was a short gap in time between the two measurements. 

Reference

Measurement of axial length in an office setting versus under general anaesthesia in infants and toddlers: a comparative study.
Hinari M, Fabian ID, Spierer A, et al.
JOURNAL PEDIATRIC OPHTHALMIC STRABISMUS
2015;52:226-30.

Paediatric Ophthalmology & Strabismology

Glaucoma management after congenital cataract
Reviewed by: Fiona Rowe
Vol 22 No5
 

The purpose of this study was to retrospectively explore the results of surgical intervention for glaucoma after congenital cataract surgery in Egypt. The study included 41 eyes of 32 children with glaucoma after cataract surgery – 57 procedures; 90% having combined procedures. There was an initial significant decline of mean IOP in the early postoperative months that showed a gradual rise over time. Cup-disc ratio showed initial mild decrease in the early postoperative months which was sustained. Successful outcome was obtained in 83%. Complications included endophthalmitis, hypotony disc oedema and retinal detachment. 

Reference

Surgical management of glaucoma after congenital cataract surgery.
Bayoumi NHL.
JOURNAL PEDIATRIC OPHTHALMIC STRABISMUS
2015;52:213-20

Paediatric Ophthalmology & Strabismology

RCT of IOL type
Reviewed by: Fiona Rowe
Vol 22 No5
 

The optical performance of pseudophakic eyes were compared after implantation of spherical and aspheric IOLs in paediatric patients after cataract surgery. This randomised controlled trial included 40 eyes of 23 patients: 20 eyes in each group. Follow-up was over three to 15 months. No complications were reported from surgery. Refraction was 0.98 ±1.12D and 0.86 ±0.85D for the spherical and aspherical groups respectively which was not significant. Best corrected visual acuity was 0.32 ±0.19 log and 0.28 ±0.16 log for the spherical and aspherical groups respectively which was not significant. There was significantly lower total wave front aberration and spherical aberration in aspheric eyes. The findings support better visual performance with aspheric IOLs and the authors therefore recommend these for IOL surgery in children. Larger studies are still required to explore this further. 

Reference

The optical performance of spherical and aspheric intraocular lenses in pediatric eyes: a comparative study.
JOURNAL PEDIATRIC OPHTHALMIC STRABISMUS
2015;52:232-8.
Raina UK, Gupta A, Bhambhwani V, et al.

Retina Vitreous & Uvea

A comparative treatment study of VCZ and liposomal AmpB in an Aspergillus fumigatus endophthalmitis model
Reviewed by: Wai Siene Ng
Vol 22 No5
 

This study aims to compare the effects of voriconazole (VCZ) and liposomal amphotericin B (AmpB) in an experimental model of exogenous Aspergillus fumigatus endophthalmitis in a guinea pig animal model. Endophthalmitis was induced by intravitreal injection of a strain of aspergillus isolated from a patient with fungal endophthalmitis. Thirty animals of similar weight were divided into three groups; a control group receiving balanced salt solution intravitreal injections, a VCZ group receiving 20µg/0.02mL intravitreal injections of VCZ and an AmpB group receiving 20µg/0.02mL of AmpB. These were administered 24 hours after Aspergillus inoculation and repeated every 24 hours for a total of three injections. They also calculated a minimum inhibitory concentration value for both antifungals, which were consistent with the results, reported by Clinical and Laboratory Standards Institute and doses administered intravitreally were much higher than these. Clinical inflammation using a published grading scale was used until day 28. Furthermore, smears and cultures were performed weekly, as well as serial electroretinogram recordings and histopathology of whole eye at the end of 28 days. Reassuringly both antifungal treatments demonstrated antifungal effects when compared to the control. Control eyes showed marked progressive inflammation but antifungal treatment groups showed inflammation, which gradually subsided. ERG in control groups demonstrated obvious reduction in b wave amplitude where else both antifungal groups did not. There was a significant difference in clinical inflammation and ERG recordings from day seven to 14 showing AmpB was less effective than VCZ, but this was not observed at later stage outcomes, therefore it is hard to conclude that VCZ is superior although the authors claims this. This study is enlightening as it allows for a controlled in vivo experiment for exogenous fungal endophthalmitis which would normally not be possible in patients due to variable inoculation times of infection, presentations and not to mention ethics. 

Reference

A comparative treatment study of intravitreal voriconazole and liposomal amphotericin B in an Aspergillus fumigatus endophthalmitis model. 
Zhao J, Cheng Y, Song X, et al.
INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE
2015;56:7369-76.

Retina Vitreous & Uvea

Diabetic polyneuropathy and risk of developing diabetic retinopathy
Reviewed by: Bheemanagouda Patil
Vol 22 No5
 

Diabetic polyneuropathy (DPN), diabetic retinopathy (DR) and diabetic nephropathy are widely classified as microvascular complications of diabetes. DPN, which may cause complete sensation loss, is another common complication of DM. The DPN-related diminished sensation presents a significant risk factor for subsequent diabetic ulcers and non-traumatic amputations. The prevalence rate of diabetic neuropathic pain is approximately 10-20% among the diabetic population, and approximately 40-60% in patients with documented neuropathy. The purpose of this study was to assess the relationship between DPN and the risk of DR. From 1997 to 2010, 5031 newly diagnosed DPN patients and 20,124 controls matched for sex, age and index year, were identified. The adjusted hazard ratio was calculated and adjusted for age, sex, duration of diabetes and comorbidities of hypertension, cardiovascular disease and diabetic nephropathy. The incidence rate of DR was 5.87-fold higher in the DPN patients than in the non-DPN group, with an adjusted HR of 5.41 (95% CI = 4.92–5.94). The DPN-to-non-DPN DR incidence rate ratio decreased with age. Compared with the non-DPN group, the DPN patients had a 5.63-fold risk of non-proliferative DR and a 3.67- fold risk of proliferative DR. 

Reference

Diabetic polyneuropathy and the risk of developing diabetic retinopathy: a nation-wide, population-based study.
Lin IC, Wang YH, Lin CL, et al.
ACTA OPHTHALMOLOGICA
2015;93:713-8.

Retina Vitreous & Uvea

Differential inhibition of EAU by CTLA4 and IL-6
Reviewed by: Graham Wallace
Vol 22 No5
 

Cytotoxic T lymphocyte antigen-4 (CTLA4) binds both CD80 and Cd86 and inhibits T lymphocyte activation via CD28. Il-6 is a pleiotropic cytokine that has been associated with many autoimmune conditions including uveitis. Blockade of these molecules by either CTLA4-Ig, a fusion protein of CTLA4 and immunoglobulin, or via an antibody against IL-6, has shown efficacy in conditions such as rheumatoid arthritis. To determine the effect of inhibiting these pathways in uveitis mice were challenged with interphotoreceptor binding protein peptide1-20 to induce experimental autoimmune uveitis (EAU), and CTLA4-Ig or anti-IL-6R was given either during induction phase (same day) or effector phase (seven days after challenge) and disease scores were assessed. The results show that both CTLA4-Ig and anti-IL-6R were effective at reducing clinical scores in animals when given at day zero. However, only CTLA4-Ig was effective at reducing disease when given at day seven when lymphocytes against IRBP1-20 had already been primed. The data was supported by in vitro studies showing that while CTLA4-Ig, but not anti-IL-6R could inhibit proliferation of IRBP1-20 specific T cells. These results show that the effectiveness of targeting different molecules involved in EAU will depend on the temporal kinetics of individual mediators of the immune response. 

Reference

CTLA4-Ig suppresses development of experimental autoimmune uveitis in the induction and effector phases: comparison with blockade of interleukin-6.
Iwahashi C, Fujimoto M, Nomura S, et al.
EXPERIMENTAL EYE RESEARCH
2015;140:51-64.

Retina Vitreous & Uvea

Genetic analysis of choroideremia families
Reviewed by: Anjali Gupta
Vol 22 No5
 

Choroideremia (CHM) is a rare X linked recessive chorioretinal dystrophy. Symptoms include nyctalopia and progressive peripheral field loss. Female carriers may have mild symptoms. Choroideremia is known to be caused by a mutation in the CHM gene. A multicentre human gene replacement clinical trial using an adeno-associated viral vector to deliver the REP1 gene to the retina is in progress with initial results showing improved visual outcomes. With the advent of gene replacement therapy, the need for genetic confirmation of choroideremia and the identification of the specific variant involved is of paramount importance. The aim of this study was to genetically analyse the cohort of families in the Australian Inherited Retinal Disease Register (AIRDR) with a familial diagnosis of choroideremia to determine the disease causing variants. Thirty-two participants from 11 unrelated families (15 affected, 10 carriers, seven unaffected) each with at least one affected male family member with choroideremia were identified and included in the study. Genetic analysis of the CHM gene was performed. Results revealed a CHM gene mutation in all 11 families with each family having a different mutation. Of the 11 mutations, there were four nonsense, four frameshift and three splice site mutations. Five mutations were novel and six had been previously reported. The authors conclude that this work is likely to facilitate access for AIRDR participants and their progeny to CHM gene therapy trials.

Reference

Genetic analysis of choroideremia families in the Australian population.
McLaren TL, De Roach JN, Montgomery H, et al.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2015;43:727-34.

Retina Vitreous & Uvea

Limbal melanocytes and the stem cell niche
Reviewed by: Graham Wallace
Vol 22 No5
 

The cornea is continually regenerated to maintain clear vision, due to a population of stem cells located in the limbal region between the cornea and the conjunctiva. These limbal stem cells (LESC) reside in crypts in structures called the Pallisades of Vogt. This LESC niche has a specific stromal matrix and cells that are on close contact with LESC. Among these stromal cells are limbal epithelial cells that help form the niche and limbal melanocytes (LM) that have been suggested to protect LESC via antioxidant production. In this paper human limbal melanocytes were prepared from cadaveric biopsies and used in culture with limbal epithelial cells (LEC) from the same source. LEC grown on LM formed large colonies that contained cells with stem cell markers and characteristics. In 3D cultures LM coculture induce multilayered epithelial structures. These results strongly support a role for limbal melanocytes in the maintenance of the LESC niche through interaction with LEC.

Reference

Limbal melanocytes support limbal epithelial stem cells in 2D and 3D microenvironments.
Dziasko MA, Tuft SJ, Daniels JT.
EXPERIMENTAL EYE RESEARCH
2015;138:70-9.

Retina Vitreous & Uvea

Limbal melanocytes and the stem cell niche
Reviewed by: Graham Wallace
Vol 22 No5
 

The cornea is continually regenerated to maintain clear vision, due to a population of stem cells located in the limbal region between the cornea and the conjunctiva. These limbal stem cells (LESC) reside in crypts in structures called the Pallisades of Vogt. This LESC niche has a specific stromal matrix and cells that are on close contact with LESC. Among these stromal cells are limbal epithelial cells that help form the niche and limbal melanocytes (LM) that have been suggested to protect LESC via antioxidant production. In this paper human limbal melanocytes were prepared from cadaveric biopsies and used in culture with limbal epithelial cells (LEC) from the same source. LEC grown on LM formed large colonies that contained cells with stem cell markers and characteristics. In 3D cultures LM coculture induce multilayered epithelial structures. These results strongly support a role for limbal melanocytes in the maintenance of the LESC niche through interaction with LEC. 

Reference

Limbal melanocytes support limbal epithelial stem cells in 2D and 3D microenvironments.
Dziasko MA, Tuft SJ, Daniels JT.
EXPERIMENTAL EYE RESEARCH
2015;138:70-9.

Retina Vitreous & Uvea

Ozurdex wound leakage
Reviewed by: Saruban Pasu
Vol 22 No5
 

This letter to the editor describes two cases of wound leakage after Ozurdex injection. The first case is a man who had four previous injections for an underlying diagnosis of chronic serpiginous choroiditis, who was also on a course of oral steroids. The fifth injection was given at the same location and with the same technique as the previous injections. The next day he presented with a reduction in both vision and IOP. The second case was a woman who had received five previous injections with a history of acute retinal necrosis and two prior vitrectomies. Again, the ladies next injection was given at the same site and with the same technique as her previous injections. Two days later she presented with reduced visual acuity and lower IOP. A small conjunctival bleb was noted at the injection site. Both cases received no treatment and both showed an improvement in vision and IOP with time. The authors remind the reader that the sclera does not heal by primary intention but is repaired with fibrous tissue. They suggest that risk factors for wound leakage in these two cases could have been systemic steroid use, previous vitrectomy and a history of multiple injections in the same location. 

Reference

Risk factors for wound leakage after ozurdex injection.
Panajaphongse R, Stewart JM.
OCULAR IMMUNOLOGY AND INFLAMMATION 
2015;23(5):410-1.

Retina Vitreous & Uvea

PD-1 and retinal ganglion cell death
Reviewed by: Graham Wallace
Vol 22 No5
 

Death of retinal ganglion cells (RGC) in conditions like glaucoma leads to permanent visual loss. RGC death can be due to the initial stress such as raised intraocular pressure or secondary to mechanism such as oxidative stress. Programmed cell death-1 (PD-1) is a receptor which is known to regulate T lymphocytes and is important in immune responses. PD-1 provides inhibitory signals that suppress such responses via pathways such as PI3 kinase and Akt signalling. A receptor for PD-1, PD-L1 is found on tumour cells and inhibits immune responses against the tumour, and blockade of this pathway has been effective in treating patients with cancer. Previous work by the authors has shown that PD-1 is constitutively expressed on RGC and that interaction with its receptor is involved during retinal development. In this paper, PD-1 expression, mRNA and protein, was increased in murine retina following optic nerve crush injury, particularly in a subset of large RGC. These PD-1 positive cells did not express cleaved caspase-3, a marker of apotosis, suggesting that PD-1 may be involved in RGC survival. The relevance of the increase in large RGC and PD-1 expression requires further study, but offers a potential pathway to influence RGC death is sight-threatening conditions. 

Reference

Programmed cell death-1 is expressed in large retinal ganglion cells and is upregulated after optic crush injury.
Wang W, Chan A, Qin Y, et al. 
EXPERIMENTAL EYE RESEARCH
2015;140:1-9.

Retina Vitreous & Uvea

Sex differences in the relationship between obesity and choroidal nevus in US adults
Reviewed by: Wai Siene Ng
Vol 22 No5
 

The National Health and Nutrition Examination Survey (NHANES); a population-based survey conducted annually in the US by the Centers for Disease Control and Prevention, was used to identify populations at higher risk for choroidal naevus. Over a period of four years, 5575 subjects aged 40 years or older completed retinal imaging from a 45° non-mydriatic retinal camera; one centred on the macula and the second centred on the optic nerve. Images defined as having a choroidal naevus were based on definitions used in other population-based studies and questionable images for naevus were excluded from analysis. Primary predictors variables used were self-reported weight history. Menopausal status, smoking history and medical history such as hypertension, diabetes and hyperlipidaemia was also self-reported. NHANES from 2005 to 2008 had 4.7% subjects with choroidal naevus on retinal imaging. They were older, more prevalent in Caucasian race, hypertensive, lower in serum HDL and fasting glucose in comparison to subjects without choroidal naevus. The multivariate logistic regression performed with age, sex and race adjusted showed elevated current BMI subjects had a 37% higher odds of choroidal naevus than those with normal current BMI and was replicated in high waist circumference at 41% higher odds. This study describes a relationship between obesity and choroidal naevus in males and females in a large cross-sectional population study. Although much of the data is self-reported with a risk for inaccurate recollection and recall bias as well as a chance for under diagnosis of naevus due to the limited field of retinal image capture, this is an important study which highlights and reiterates the associations between obesity and a potentially cancerous lesion. 

Reference

Sex differences in the relationship between obesity and choroidal nevus in US adults. 
Sieburth R, Qiu M, Shields C.
INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE
2015;56:7489-95.

Retina Vitreous & Uvea

Subthreshold micropulse laser treatment in chronic central serous chorioretinopathy
Reviewed by: Sofia Rokerya
Vol 22 No5
 

This retrospective study was conducted to assess the treatment of 38 patients of chronic central serous chorioretinopathy with a 577-nm subthreshold micropulse laser (SML) Supra Scan Quantel Medical. Eighteen patients of these had persistent subretinal fluid (SRF) after photodynamic therapy. Thirty-eight eyes of 38 consecutive patients (29 men and nine women) were included in the analysis. The mean age of the patients was 51 years (range 32–69). The mean duration of disease before SML treatment was four years (range four months to 19 years). In this study, 17 eyes received one SML treatment, 15 eyes two, and six eyes three SML treatments. Assessment included visual acuity (VA), central retinal thickness (CRT) and resolution of SRF. Patients with evidence of other retinal diagnoses, such as choroidal neovascularisation or polypoidal choroidal vasculopathy, were excluded. Laser spots were applied with the Area Centralis contact lens (laser spot magnification ×0.94. The spot size was 160µm, the exposure time 0.2s, and a duty cycle of 5% was used. (A duty cycle of 5% allowed for the heat production time to be shorter than the thermal relaxation time for the space between the retinal pigment epithelium (RPE) and the neural retina, resulting in axial confinement of the increased heat at RPE). For confluent laser treatment, the multispot mode was chosen. The individual power for the patient was titrated at a normal area of the retina, near the affected area in the monospot micropulse mode. The power titration was started at 700mW and then gradually increased until a just visible burn was seen. When this threshold was reached, the power was reduced by 50%. The treatment outcome was evaluated using the best-corrected VA (BCVA), CRT and resolution of SRF. The BCVA improved in 17 out of 38 eyes (45%) by one or more lines (in eight eyes by one line, in five eyes by two lines and in four eyes by three or more lines). Fourteen eyes (37%) maintained vision, and seven eyes (18%) lost one or two lines (five eyes one and two eyes two lines). In most cases, the functional response set in early, while BCVA improved over a longer period of time. At the last follow-up (mean five months), 74% of patients responded to therapy. The CRT decreased after treatment (mean CRT –115µm, p<0.001) and VA improved (mean logMAR –0.06, p=0.039). No laser burns were detected with any imaging modality. In the subgroup of patients resistant to photodynamic therapy (PDT), 61% of patients responded to therapy with a decrease in CRT (mean CRT –75µm, p=0.019). The 577-nm SML was found to be an effective treatment for cCSC even in patients without sufficient improvement after PDT. Limitations of study include lack of randomised control trial (RCT), and short follow-up time. 

Reference

Subthreshold micropulse laser (577 nm) treatment in chronic central serous chorioretinopathy. 
Scholz P, Ersoy L, Boon CJF, Fauser S.
OPHTHALMOLOGICA 
2015;234:189-94. 

CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY

Phaco-ECP vs. Phaco alone to treat glaucoma
Reviewed by: Anjali Gupta
Vol 22 No 4
 

This retrospective review compared combined phacoemulsification and endoscopic cyclophotocoagulation (phaco-ECP) to phaco alone in patients with mild to moderate glaucoma. Outcome measures included cumulative full and qualified success survival, postintervention IOP and ocular anti-hypertensive medication reduction. Full success was defined as a minimum of 20% reduction of IOP with a decrease in at least one ocular anti-hypertensive medication, qualified success was defined as an IOP no higher than preoperative with a decrease in at least one ocular anti-hypertensive medication. There were 261 eyes in the phaco-ECP group and 52 eyes in the phaco alone group. All patients were diagnosed with mild to moderate glaucoma controlled medically preoperatively with one to three ocular anti-hypertensive medications. Results showed that both phaco-ECP and phaco alone effectively lowered the IOP in the long-term when compared to baseline. At 36 months, the mean number of medication reliance in the phaco-ECP group was 0.2 compared to 1.3 in the phaco alone group; 61.4% reached full success in the phaco-ECP group compared to 23.3% in the phaco alone group. In the phaco-ECP group 72.6% reach qualified success compared to 23.3% in the phaco alone group. All these results were statistically significant. Complications that occurred in the phaco-ECP group included cystoid macula oedema (four cases), retinal detachment (two cases), the need for secondary glaucoma procedures (seven cases) and the need for a penetrating keratoplasty (one case). In conclusion, combined phaco-ECP is more effective in treating mild to moderate glaucoma when compared to phaco alone.

Reference

Combined endoscopic cyclophotocoagulation and phacoemulsification versus phacoemulsification alone in the treatment of mild to moderate glaucoma.
Siegel MJ, Boling WS, Faridi OS, et al.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2015;43:531-9.

JOURNAL OF CATARCT AND REFRACTIVE SURGERY

Simple approach to prevent capsule tear-out during capsulorhexis creation in hyper mature cataracts
Reviewed by: Sharmina Khan
Vol 22 No 4
 

Puncturing the anterior capsule in the anterior chamber so that the pressure falls below intracapsular tension causes the rhexis to extend out to the equator. If this develops into a tear that wraps around the entire lens it is called the Argentinian flag sign. A heavy molecular weight ophthalmic viscosurgical devices (OVD) can ensure the anterior chamber pressure is maintained above intracapsular pressure. Femto-second laser is a method to complete capsulotomy with minimal / no risk of tear out. The authors describe a simple technique of inserting Healon GV or Healon 5 through a small side port incision 21-gauge 0.8mm side port incision until flattening of the anterior capsule is observed indicating that anterior chamber is greater than intracapsular pressure. The central capsule is cut with forceps tip and rhexis completed without exiting the anterior chamber until rhexis is complete, the rhexis is sized so that it plugs the incision and OVD cannot flow out of the anterior chamber. This technique is also supposed to prevent the outflow of liquefied milky cortex. It also avoids having to aspirate liquified cortex but doesn’t allow maintaining anterior chamber pressure.

Reference

Simple approach to prevent capsule tear-out during capsulorhexis creation in hyper mature cataracts.
Robinson MS, Olson RJ.
JOURNAL OF CATARCT AND REFRACTIVE SURGERY
2015;41:1353-5.

ACTA OPHTHALMOLOGICA

AMD and visceral fat and pro-inflammatory factors
Reviewed by: Bheemanagouda Patil
Vol 22 No 4
 

Several large studies have shown a positive relationship between age-related macular degeneration (ARMD) and high body mass index. The waist-hip ratio is also associated with development of early AMD. Visceral fat has a pro-inflammatory effect, which means it has an influence on immune system through the production of various neurotransmitters. The aim of this case-control study was to determine the relationship of the body fat distribution in patients with ARMD compared to a healthy control group with a normal fundus in the Austrian population using dual-energy X-ray absorptiometry. Fifty-four patients with exudative ARMD and 46 gender- and age-matched control subjects were included in the study. DEXA revealed central-abdominal-to-total body fat ratio of 0.073 +/ _ 0.011 in AMD patients compared to 0.061 +/_ 0.013 in the controls (p<0.001; d=0.98). The calculation of BMI has provided a significant result (p=0.045). U-test results for Aß1-42, IL-6, SAA and CRP each were significant (p<0.05), with higher values in AMD patients. Leptin, TNF-alpha and Aß1-40 showed no significant differences between the groups. The study concluded that abdominal fat distribution is significantly associated with age-related macular degeneration. Analysis of patients with exudative AMD revealed higher levels of CRP, amyloid ß1-42, IL-6 and amyloid alpha.

Reference

Impact of visceral fat and pro-inflammatory factors on the pathogenesis of age-related macular degeneration.
Haas P, Kubista KE, Krugluger W, et al.
ACTA OPHTHALMOLOGICA
2015;93:533-8.

ACTA OPHTHALMOLOGICA

Climatic droplet keratopathy
Reviewed by: Bheemangouda Patil
Vol 22 No 4
 

Climatic droplet keratopathy (CDK) is an acquired and potentially handicapping corneal degenerative disease that is highly prevalent in certain rural communities around the world. It predominantly affects males in their 40’s and is known by many other names such as Bietti’s band-shaped nodular dystrophy, Labrador keratopathy, spheroidal degeneration, chronic actinic keratopathy, oil droplet degeneration, elastoid degeneration and keratinoid corneal degeneration. CDK is characterised by the haziness and opalescence of the cornea’s most anterior layers, which go through three stages with increasing severity. Globular deposits of different sizes may be histopathologically observed under the corneal epithelium by means of light and electron microscopy. The coalescence and increased volume of these spherules may cause the disruption of Bowman’s membrane and the elevation and thinning of the corneal epithelium. The exact aetiology and pathogenesis of CDK are unknown, but they are possibly multifactorial. The only treatment in CDK advanced cases is a corneal transplantation, which in the impoverished regions of the world is not an available option. This review highlights new scientific evidence of the expanding knowledge on CDK’s pathogenesis, which will open the prospect for new therapeutic interventions.

Reference

Climatic droplet keratopathy: an old disease in new clothes.
Serra HM, Holopainen JM, Beuerman R, et al.
ACTA OPHTHALMOLOGICA
2015;93:496-504.

AMERICAN JOURNAL OF OPHTHALMOLOGY

The disease burden of AMD
Reviewed by: Efrosini Papagiannuli
Vol 22 No 4
 

In this multi-centre, prospective, observational, time and motion study the authors assessed the time burden of managing wet AMD for doctors, staff, patients and caregivers in the USA. The study spanned the period from March 2011 to August 2012, and surveys were conducted of 56 retina specialists across the country that provided data for 221 patients. There were three parts to the study: 1) ethnographic data collection, 2) qualitative patient and care givers interviews and 3) quantitative surveys of both patients and retinal specialists. Another qualitative survey was conducted of 75 wet AMD patients who had received at least 1 anti-VEGF injection in the previous six months, including preparation for the appointment, travel, waiting times, treatment times and post intervention recovery. Thirteen caregivers were interviewed by phone about the time investment to provide transport to appointments. The results were interesting: around 23 healthcare staff members (receptionist, practice manager, billing manager, technicians, doctors) were involved, with 20% of their work time per week invested in the management of wet AMD patients. The average time spent by patients per visit was 90 minutes, ranging from 13 minutes to more than four hours. The patients themselves spent almost 12 hours per visit and that included pre-appointment preparation (16 minutes), travel (66 minutes), waiting time (37 minutes), treatment time (43 minutes) and post-appointment recovery time (nine hours). Seventy-two percent of patients were driven to their appointment by a caregiver, who in the majority was a spouse / partner (65%), followed by an adult child or grandchild (22%), or friend (7%). Twenty percent of patients drove themselves to the appointment. The care givers time investment for transportation accounted between 22% (time away from work) and 28% (time away from personal activities). The majority of retina specialists thought that the frequency of injections and associated patient visits were the biggest contributor to the disproportionate use of materials and office space. The authors conclude that the management of wet AMD places a hefty time burden to all staff involved as well as a quality of life burden for patients and care givers. They point out the strength of their study with its very comprehensive methodology, including both physician and patient perspectives, and the sampling of retinal specialists from a wide range of locations (20 US states) with a wide patient demographic. They are also aware of the possibility of selection bias in which specialists chose to participate and also the possible effect of potentially inaccurate reporting (reliability of responses). Furthermore they highlight the possible need for additional support and reimbursements for these services and the potential of such a study to be conducted in other countries and markets.

Reference

Disease burden in the treatment of age-­related macular degeneration: findings from a time and motion study.
Prenner JL, Halperin LS, Rycroft C, et al.
AMERICAN JOURNAL OF OPHTHALMOLOGY
2015;160(4):725-31.

CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY

Clinical characteristics and outcomes of open globe injury
Reviewed by: Anjali Gupta
Vol 22 No 4
 

This retrospective cohort study examined consecutive open globe injuries at a tertiary referral centre over a three year period. The aim of the study was to detail the clinical characteristics of open globe injuries and to explore their association with clinical outcomes, particularly postoperative wound related issues. Two hundred and sixty-seven eyes of 263 patients were included in the study. Of the cases, 82.5% were male and the mean age at presentation was 44.8 years. Penetrating injuries made up 68.2%, 31.1% globe ruptures and 0.7% perforating injuries. A total of 16.1% of eyes had an intraocular foreign body; 46.5% of these were in the posterior segment; 37.1% cases had a lens capsule breach. Regarding clinical outcomes following repair, over half of cases had improved VA at final follow-up. In total 47.2% of eyes had a final VA equal or better than 6/12 and 37.1% eyes had a final VA worse than 6/60. Factors that were associated with a poor VA included ≥50 years of age, globe rupture, presenting VA <6/60 and retinal detachment. Of the cases 16.4% had a wound leak following repair. Factors contributing to wound leak included stellate shaped wound and delayed presentation (>24 hours). Post traumatic endophthalmitis was seen in 3.7% cases. Risk factors for endophthalmitis included lens capsule breach, microbial keratitis and delayed presentation. The authors conclude that prompt and meticulous management of open globe injuries may reduce the complications of wound leak and endophthalmitis.

Reference

Wound related complications and clinical outcomes following open globe injury repair.
Kong GYX, Henderson RH, Sandhu SS, et al.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2015;43:508-13.

CORNEA

Same day air bubble removal after DSEK/DSAEK
Reviewed by: Magdalena Popiela
Vol 22 No 4
 

A complete air removal on same day as descemet’s stripping endothelial keratoplasty (DSEK/DSAEK) leads to prompt restoration of the anterior chamber and thus has been hypothesised to assist with the recovery of endothelial function and promote graft adhesion. The results of this retrospective analysis of single surgeon’s experience over 10 years included 310 patients. All underwent DSEK/DSAEK with complete air bubble removal approximately one hour after their surgery. Overall detachment rate in the whole group was 6.1% – comparable to results in conventional surgery. In the last year of the study graft detachment rate of 1.3% was recorded, which was linked to improved surgeon’s experience and modification of surgical technique. Introduction of mid-peripheral corneal venting incisions, strict removal of all fluid from donor-host interface aided by a use of LASIK flap roller and roughening the peripheral recipient bed to promote donor edge adhesion were introduced to improve graft detachment rate. The rates of late endothelial graft failure (8.1%) and graft rejection (10.7%) were comparable to those reported following conventional surgery. This study shows that low rates of DSEK/DSAEK graft detachment are achievable with complete air removal on the same day, lowering the risk of pupillary block glaucoma and reducing the potential risk of air toxicity to the corneal endothelium.

Reference

Graft detachment rate in DSEK/DSAEK after same-day complete air removal graft.
Lehman RE, Copeland LA, Stock EM, Fulcher SF.
CORNEA
2015;34(11):1358-61.

EYE

Age-related macular degeneration
Reviewed by: Nana Theodorou
Vol 22 No 4
 

This review article offers an up to date review of the genetic and environmental risk factors associated with aetiology surrounding age-related macular degeneration (AMD). The article briefly describes the typical clinical presentation relating to early and late stages of the disease. The recent discovery of the highly toxic Aβ peptide in the ageing retina serves as the main review point. The authors describe recent studies conducted on the amyloid precursor protein (APP) gene located on chromosome 21q21. For those interested in the underlying pathophysiology of AMD this is a detailed account of recent evidence to explain the ageing retina. There are no direct clinical links but a good overview of the underlying aetiology.

Reference

Dementia of the eye: the role of amyloid beta in retinal degeneration.
Ratnayaka JA, Serpell LC, Lotery AJ.
EYE
2015;29:1013-26.

EYE

Computerised visual acuity measurements in AMD
Reviewed by: Nana Theodorou
Vol 22 No 4
 

The aims of this study were to investigate whether half-letter width spacing in COMPlog algorithms had an adverse effect on agreement in patients with AMD with the ETDRS chart. Fifty adult participants with AMD took part with a median age of 86 years. All patients had six measurements of their visual acuity, two of which were with the ETDRS chart and the other three with the COMPlogC5 and C3. Most of the patients had wet AMD (44/50). The C5 and C3 scores showed no bias compared to the ETDRS. C5 measurements had equal test-retest variability to the ETDRS but the C3 were slightly more variable but 30s quicker. The authors conclude that both VA tests can be used with equally accurate results in patients with AMD.

Reference

Performance of a computerised visual acuity measurement device in subjects with age-related macular degeneration: comparison with gold standard ETDRS chart measurements.
Bokinni Y, Shah N, Maguire O, et al.
EYE
2015;29:1085-91.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Advice on activity post-surgery
Reviewed by: Fiona Rowe
Vol 22 No 4
 

The authors aimed to identify common postoperative policies among AAPOS members to enable strabismus surgeons to compare their practices with those of colleagues. A survey was circulated which contained 12 multi-choice questions. One hundred and eight responses were received, of which six were excluded. Responses included the following: 96% routinely performed strabismus surgery – 86% in the US and Canada, 14% international: 75% had been in practice for >10 years; 53% had paediatric practices in private offices, 27% in academic centres and 21% in combined practice types. Half stated they allow normal showering or bathing on the first day after surgery; 52% allow return to education after three to four days; 47% advise restraint from sandbox play for at least two weeks – 44% for one week; 43% indicate a wait of one week before physical sports activity; 56% advocate a wait of two weeks before swimming and 47% advise a wait of two weeks before using contact lenses.

Reference

Instructions to patients and families following strabismus surgery.
Doton G, Qureshi HM, Nelson LB.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:142-6.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Amblyopic choroidal thickness
Reviewed by: Fiona Rowe
Vol 22 No 4
 

The authors studied choroidal thickness in 38 paediatric cases (76 eyes) with unilateral amblyopia to evaluate the differences between amblyopic and fellow eyes, and compare them with 19 healthy control subjects (38 eyes). Anisometropic amblyopia was present in 17 cases and strabismic amblyopia in 21 cases. The mean age was 11.31 ±3.01 years in patients and 11.84 ±3.17 years in controls. Mean best corrected visual acuity was 0.40 ±0.17 logMAR in strabismic amblyopia, 0.48 ±0.18 in anisometropic amblyopia and 1.0 ±0 in fellow eyes and controls eyes. Central macular thickness in amblyopic eyes (248.31 ±24.18um) did not differ significantly from fellow eyes (249.76 ±26.08) and controls (243.65 ±31.96). Subfoveal and parafoveal choroidal thickness was thicker in amblyopic eyes than fellow and control eyes. Type and depth of amblyopia did not influence differences. Peripapillary thickness was not significantly different between eyes. The authors conclude the amblyopia process may involve the choroid but not the macula.

Reference

Analysis of choroidal thickness using spectral-domain OCT in children with unilateral amblyopia.
Kara O, Altintas O, Karaman S, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:159-66.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Effectiveness of Eagles Eye Mobile
Reviewed by: Fiona Rowe
Vol 22 No 4
 

The EEM programme was created to target children failing school nurse screening and likely to not have access to eye care. The EEM visits schools in low income areas providing optometric examinations to detect correctable refractive error, prescribe and deliver glasses, and arrange paediatric ophthalmology examinations at no cost to the child. The authors aimed to assess the EEM programme ability to achieve its objective. From September 2006-June 2008, 6365 children were seen by EEM. 78.2% were given free glasses and 14.5% were referred to the ophthalmologist. For school screening, the false positive rate ranged from 0-44% (median 15.38, mean 16.11%). For a sample of those given glasses at four month follow-up, younger age was associated with increased odds of wearing the glasses as was lower grade at school. At 12 months, only higher glasses strength in near sighted eyes was associated with increased odds of wearing glasses. For ophthalmology referrals, 53.3% were recorded as attending. Referrals were for suspected amblyopia, glaucoma, ocular alignment or ocular motility abnormality / nystagmus. Only 6.1% were classified as resolved: the remainder required follow-up. The authors conclude EEM is effective with a requirement for school nurse training to reduce false positive screening and strategies to improve attendance at ophthalmology examination.

Reference

The Eagles Eye Mobile: assessing its ability to deliver eye care in a high-risk community.
Alvi RA, Justason L, Liotla C, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:98-105.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Facilitators and barriers to conducting research
Reviewed by: Fiona Rowe
Vol 22 No 4
 

A survey of clinicians and researchers across the UK was conducted to identify barriers to research and potential solutions. The authors extracted details of studies listed on the UKCRN database that involved paediatric ophthalmology with recruitment of children. An e-survey was sent out to evaluate researchers’ experiences. Forty two studies were identified – 26 active and 16 closed / suspended. Four added studies were identified from searching other speciality group database entries. Eighteen studies were based in London and the remainder elsewhere in the UK (Newcastle, Liverpool, Manchester, Edinburgh, Leeds, Leicester and Southampton). Most addressed phenotype / genotype and observation studies. Four were RCTs. A survey was distributed to research teams with 51 returns relating to 23 of the 46 studies. Ninety-two percent had or were involved in UKCRN portfolio studies. Thirty-nine percent of responses were from site principal investigators. Seventy-eight percent were based at tertiary referral centres. Sixty percent confirmed recruitment was to target. Experience, presence, motivation and availability of a designated research team were the strongest facilitators for recruitment. Family attitudes toward taking interventional medications or placebos or preference for a treatment were the strongest barriers. Administrative difficulties such as opening sites and burden of additional visits or investigations were also strong barriers. Improvements in support, time, space, communication, protocols, patient and public involvement, and ethical / NHS approval / administration would improve recruitment.

Reference

Delivering clinical trials and observation studies in child eye health: a nationwide survey in the UK.
Banteka M, Tailor U, Dalmann-Noar A.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:106-12.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

MR- vs. LR+ for divergence insufficiency
Reviewed by: Fiona Rowe
Vol 22 No 4
 

A retrospective study was conducted to compare the efficacy of medial rectus recession and lateral rectus resection as surgical interventions for divergence insufficiency in 18 patients. These were cases of non-neurological cause. Two patients in each group required postoperative adjustment. Of nine patients in the medial rectus group, no patient had reoperation for diplopia but one required prisms. Of nine patients in the lateral rectus group, no patient had reoperation for diplopia but three developed distance esotropia requiring prisms or exercises and one developed near exophoria requiring exercises. Both methods were found to be effective in reducing symptoms and the near / distance deviation disparity.

Reference

Comparison of the efficacy of medial rectus recession and lateral rectus resection for treatment of divergence insufficiency.
Breidenstein BG, Robbins SL, Granet DB, Acera EC.     
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:173-6.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Normal videonystagmography data
Reviewed by: Fiona Rowe
Vol 22 No 4
 

The authors report on the smooth pursuit and saccadic eye movement waveforms elicited from normal patients while viewing standardised calibrated targets. Serial trials were performed on each patient to determine test / retest reliability: nine trials producing 117 results by three different examiners. Patients were assessed by multiple examiners to evaluate intra-examiner variability. Eye movement waveforms were elicited from normal patients (13 patients aged 18 years or older). Five movement characteristics included saccadic latency, velocity and precision, pursuit gain and velocity. Overall test / retest variability was low where the median coefficient of variation (CV) of the three testers for all five eye movement categories was less than 15%, and less than 10% of the CVs calculated were more than 20%. With low test / retest variability the VNG system is considered reliable to produce repeated measurements with consistency when operated by the same person. The authors propose that changes >20% before and after treatment in future study data can be attributed to treatment effect where patients are tested by the same examiner. Significant inter-observer variability was noted due to setup variations. Therefore future studies should aim for the same examiner for all visits.

Reference

Reliability and application variability of a commercially available infrared videonystagmography unit.
Gerling A, Leu SY, Morton A5, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:114-8.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

The clinical spectrum of albinism
Reviewed by: Fiona Rowe
Vol 22 No 4
 

The authors sought to examine clinical correlates that may be related to foveal development in albinism with an aim to qualitatively describe the phenotype spectrum of albinism. Binocular best corrected visual acuity ranged from 20/20 to 20/80. Best corrected visual acuity of the imaged eye ranged from 20/20 to 20/100. All had positive angle kappa and eight had a temporal preferred retinal fixation locus. Worse visual acuity was associated with larger angle kappa. Four patients with visual acuity of >20/40 had no nystagmus. Ten had various forms of nystagmus. Five had granular melanin pigment in the macula and all of these had visual acuity >20/40. Four had macular melanin pigmentation and a foveal avascular zone – three with a rudimentary annular reflex. Three had granular macular pigmentation and normal inner / outer segment lengths with indistinct foveal pit. The authors conclude there is a spectrum of best corrected visual acuities, clinical and imaging findings in albinism. Retinal thickness does not correlate with best corrected visual acuity.

Reference

Clinical insights into foveal morphology in albinism.
McCafferty BK, Wilk MA, McAllister JT, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:167-72.

NEURO-OPHTHALMOLOGY

Positive diagnosis of acute posterior ischaemic optic nerve neuropathy
Reviewed by: Claire Howard
Vol 22 No 4
 

Posterior ischaemic optic neuropathy is a rare cause of visual loss believed to be due to infarction in the territory of the pial branches of the ophthalmic artery. There is an absence of clinical signs which means the diagnosis is one of exclusion. This case study article presents two patients who developed posterior ischaemic optic neuropathy which was confirmed by the observation of secondary changes on diffusion-weighted imaging sequences. In the first case, visual loss followed robotic pelvis surgery and in the second it was associated with multiorgan dysfunction secondary to severe pancreatitis. A comprehensive review of the literature is also presented. The cases demonstrate that this imaging method can provide a positive diagnosis of posterior ischaemic optic nerve injury in the acute phase. This has a clinical implication for assessment and diagnosis of patients with this rare visual disorder. An objective positive confirmation of the diagnosis can be very helpful, particularly in the difficult postoperative situation where loss of vision has occurred following a surgical procedure with no direct relationship to vision.

Reference

Using diffusion-weighted magnetic resonance imaging to confirm a diagnosis of posterior ischaemic optic neuropathy: two case reports and literature review.
Quddus A, Lawlor M, Siddiqui A, et al.
NEURO-OPHTHALMOLOGY
2015;39(4):161-5.

NEW ENGLAND JOURNAL OF MEDICINE

A phase 3 randomised trial of nicotinamide for skin cancer chemoprevention
Reviewed by: Jonathan C P Roos
Vol 22 No 4
 

To B3, or not to B3? That was the question asked in this controlled trial in which the authors were able to show that oral nicotinamide (vitamin B3) is able to reduce further skin cancer development in high risk patients. The study was limited to non-melanoma skin cancer.  Previous results had suggested that B3 can protect against UV damage and likely does so by enhancing immune system function which can otherwise be downregulated by UV light-induced damage. So the authors recruited 386 patients with at least two previous non-melanoma skin cancers in the preceding five years. Using a double-blind trial design, they were assigned randomly to either have 500mg Vitamin B3 twice a day, or placebo for 12 months and were then followed for a total of 18 months, being reviewed clinically every three months during that period by dermatologists. The primary aim was to see if there was a difference in the number of new basal and squamous cell carcinomas forming during that period between the B3-treated group versus placebo-controls. The authors found that the Vitamin was well tolerated and there were no side-effects attributable to its ingestion. After a year, the data showed that the rate of non-melanoma skin cancer formation in the treated arm was 23% lower overall: 20% less basal cell and 30% less squamous cell carcinomas. Furthermore the rate of actinic keratoses was also lower at 20%.  Interestingly, upon cessation of treatment, the remaining six months of the study showed no continued benefit of the treatment, indicating that it must be ingested continuously to sustain the anti-tumour effect. This study, conducted in Australia, should have a significant effect on public health at a time when skin cancers are on the rise. The area is complex however, as use of non-steroidal anti-inflammatory drugs has previously also been linked to a reduction in non-melanoma skin cancer; the role of the immune system and inflammation in these disorders is more complex than might first appear.

Reference

A phase 3 randomized trial of nicotinamide for skin-cancer chemoprevention.
Chen AC, Martin AJ, Choy B, et al.
NEW ENGLAND JOURNAL OF MEDICINE
2015;373:1618-26.

OCULAR IMMUNOLOGY & INFLAMMATION

ARN in North Africa
Reviewed by: Saruban Pasu
Vol 22 No 4
 

Acute retinal necrosis (ARN) is a rare cause of uveitis. This paper aims to outline the clinical features of 12 patients with ARN in a referral centre in Tunisia, North Africa. A retrospective review of case notes was carried out. The extent of retinal necrosis was labelled as mild if <25%, moderate if 25-50% and severe if >50%. The treatment protocol consisted of IV acyclovir for 7-10 days followed by oral acyclovir for at least 12 weeks. Intravitreal gancyclovir was used when systemic antivirals were contraindicated. Oral steroids were added when the retinitis had regressed or been stable for several days. Polymerase chain reaction (PCR) on aqueous humour was done in all patients allowing for identification of the causative agent in 54.5%. HSV-1 was found in 33.3%, VZV in 25% while no HSV-2 or CMV were isolated. The authors note that the combination of systemic and intravitreal antiviral therapy seems to be superior to systemic antiviral treatment alone, in terms of visual prognosis and retinal detachment occurrence. In this case series, retinal detachment occurred only in eyes with more than or equal to 25% of retinal involvement. A total of 58.3% of patients had a final VA of 20/200 or worse. Poor visual outcome was associated with the following: duration between symptoms and treatment initiation more than 14 days, macular involvement, development of retinal detachment and retinal involvement of 25-50%. The use of oral steroids prior to antiviral treatment lowered the speed of retinitis healing. This paper is the first of its kind to describe features of acute retinal necrosis from North Africa.

Reference

Pattern of acute retinal necrosis in a referral center in Tunisia, North Africa.
Khochtali S, Abroug N, Kahloun R, et al.
OCULAR IMMUNOLOGY & INFLAMMATION
2015;23(5):371-7.

OPHTHALMIC EPIDEMOLOGY

Neighbourhood deprivation and risk of age-related eye diseases
Reviewed by: Jonathan C P Roos
Vol 22 No 4
 

In this large epidemiological study, the authors sought to determine if neighbourhood wealth affects age-related ocular health. In particular they wished to see if there was a correlation between social deprivation and macular degeneration, cataract, diabetes-related eye complications, and glaucoma. Such research is of course open to confounders, including the effect of immigration, and for this reason a very large sample was used: approximately 4.5 million Swedish residents – almost half the country’s total population. For a decade (or until they came under the care of the ophthalmic services, died or emigrated) 2,060,887 men and 2,250,851 women aged 40 years were followed. Residents were divided up into cohorts of 1000 people and a deprivation scale calculated based on four variables: low educational level, low income, unemployment and receipt of social welfare payments. Logistic regression analysis, adjusting for confounders, showed that in men the odds ratio for developing macular degeneration, cataract, diabetes and glaucoma were all increased for those in more deprived neighbourhoods (odds ratios 1.08, 1.31, 1.36, and 1.11 respectively). The same was true for women (odds ratios 1.11, 1.36, 1.50, and 1.12 respectively). The authors concluded that their study implicates both individual and neighbourhood factors which could prove helpful in preventing age-related eye disease. This is the first largescale multilevel study to examine the effect of neighbourhood deprivation on age-related eye diseases but its results fit with previous work, such as in Scotland, where severity of glaucoma at presentation was associated with neighbourhood deprivation. A UK study, similarly showed an association between acute angle closure and higher levels of neighbourhood deprivation.

Reference

Neighborhood deprivation and risk of age-related eye diseases: a follow-up study in Sweden.
Hamano T, Li X, Tanito M, et al.
OPHTHALMIC EPIDEMOLOGY
2015;22(5):308-20

OPHTHALMOLOGICA

Comparison of retinal pigment epithelium-choroid graft surgery and anti-VEGF therapy in patients with wet AMD
Reviewed by: Sofia Rokerya
Vol 22 No 4
 

This was a randomised intervention study in wet AMD patients to investigate benefits of free RPE-choroid graft transplantation surgery versus (continuation of) anti-VEGF treatment. Twenty patients who met the inclusion criteria were subdivided into three subgroups, i.e. RPE tears involving the macula, submacular haemorrhages, or nonresponders to anti-VEGF. Patients were randomised to group 1: submacular haemorrhage, graft (n=6); group 2: RPE tear, graft (n=3); group 3: nonresponder, graft (n=1); group 4: submacular haemorrhage, anti-VEGF (n=5); group 5: RPE tear, anti-VEGF treatment (n=3), and group 6: nonresponder, anti-VEGF treatment (n=2). The results showed change in the mean number of Early Treatment of Diabetic Retinopathy Study (ETDRS) letters in the graft group one year postoperatively was –15 (range –54 to +26), whilst two patients experienced a gain of >10 letters. Gain results: two; loss: four; stable: three; LFO: one. The median preoperative visual acuity (VA) was 0.75 logMAR (range 0.46–2.8), and the mean postoperative VA was 1.48 logMAR (range 0.14–2.8). The change in the mean number of ETDRS letters in the anti-VEGF group was –8 (range –26 to +6); no patients experienced a >10 letter gain. Gain results: zero; loss: three; stable: six; LFO: one. The median preoperative VA was 1.36 logMAR (range 0.58–1.6), and the median postoperative VA was 1.42 logMAR (range 0.44–1.66). The study indicates that the RPE-choroid graft surgery may be considered as an alternative in the treatment of cases in which no other treatment option is available, e.g in patients with still relatively preserved retinal layers in the macular region with a relatively fresh RPE-choroid tear, or a submacular haemorrhage which is too old to be treated with recombinant tissue plasminogen activator and / or too thick to be treated with anti-VEGF therapy. In these patients no therapy or removal of the haemorrhage alone had a poor result. As regards the complications incurred in this study cohort: in the RPE-choroid graft group, recurrent retinal detachment due to proliferative vitreoretinopathy (PVR) developed in three out of 10 patients, severe hypotony in two (one without PVR) and recurrent submacular hemorrhage in three patients (two without PVR). cerebrovascular accident occurred in one patient. In the anti-VEGF group, a recurrent retinal detachment due to PVR developed in one out of 10 patients, a transient ischaemic attack in two, and a minor stroke occurred in one patient. Patients in the RPE-choroid graft group suffered more complications. VA gain and loss was obtained by both treatment methods. The authors suggest that greater VA gain might be possible for patients who undergo an RPE-choroid graft transplantation surgery than those who continue with anti-VEGF treatment alone. However, this may come at the risk of some severe complications. Limitations of this study were the small  cohort, single centered and short follow up period.

Reference

Comparing retinal pigment epithelium-choroid graft surgery and anti-VEGF therapy in patients with exudative age-related macular degeneration.
van Zeeburg EJT, Cereda MG, Amarakoon S, van Meurs JC.
OPHTHALMOLOGICA
2015;233:134-45.

OPHTHALMOLOGY

Cataract surgery and circadian photoentrainment
Reviewed by: Brian Ang
Vol 22 No 4
 

The study authors sought to investigate the possible effects of circadian photoentrainment following cataract. This was a randomised clinical trial, where 76 eyes of 76 patients (with bilateral cataract) were randomised to blue-blocking or neutral intraocular lenses (IOLs). Outcome measures included activation of intrinsic photosensitive ganglion cells to blue light, actigraphy to analyse circadian rhythms, 24-hour salivary melatonin measurements, and the Pittsburgh Sleep Quality Index. Most of the circadian and sleep-specific actigraphy parameters were not significantly altered after surgery, and thus the study authors concluded that cataract surgery was unlikely to significantly affect sleep. Additionally, there was no significant difference between blue-blocking and neutral IOLs – IOL selection should therefore be based on the patient’s clinical need rather than concern over the possibility of sleep being adversely affected.

Reference

The effect of cataract surgery on circadian photoentrainment. A randomized trial of blue-blocking versus neutral intraocular lenses.
Brondsted AE, Sander B, Scient C, et al.
OPHTHALMOLOGY
2015;122:2115-24.

OPHTHALMOLOGY

Intravitreal aflibercept for diabetic macular oedema
Reviewed by: Brian Ang
Vol 22 No 4
 

The VISTA and VIVID randomised phase 3 trial were designed to compare the efficacy and safety of intravitreal aflibercept injections versus laser photocoagulation for diabetic macular oedema (DMO). A total of 872 patients with centrally involving DMO were recruited, and those randomised to aflibercept either had 2mg injected every four weeks or every eight weeks after five monthly doses. Intravitreal aflibercept was superior to laser both in terms of visual and anatomic outcomes at 52 weeks; the benefit was sustained through to week 100. The commonest adverse event was cataract (2.4% for the four-weekly injections and 1.0% for the eight-weekly injections). The ability to control DMO with eight-weekly injections over the longer term will hopefully help to ease some of the workload in retina and injection clinics.

Reference

Intravitreal aflibercept for diabetic macular edema. 100-week results from the VISTA and VIVID studies.
Brown DM, Schmidt-Erfuth U, Do DV, et al.
OPHTHALMOLOGY
2015;122:2044-52.

ORBIT

Managing blepharophimosis
Reviewed by: Konal Saha
Vol 22 No 4
 

The authors present a prospective study of a one-stage technique for managing both telecanthus and ptosis seen in blepharophimosis syndrome. The technique involves carrying out a Y to V medial canthoplasty followed by a frontalis suspension which the authors carry out using Tutopatch which is irradiated bovine pericardium. They carried out the technique on 12 eyes of six patients. It was a young group of patients (median age 14 months) and all were deemed to be at risk of amblyopia with superior margin reflex distances varying between -1mm and +1mm. The results showed a statistically significant change in margin reflex distance (MRD), inner intercanthal distance (IICD) and horizontal fissure length (HFL). The clinical change in MRD was approximately 2mm, IICD 6.5mm and HFL 3mm. No unexpected complications were encountered with 33% of patients having temporary lagophthalmos. The paper is supportive of correcting the ptosis and telecanthus seen in blepharophimosis patients in one rather than two stages.

Reference

A modified one-stage early correction of blepharophimosis syndrome using tutopatch slings.
Savino G, Mandara E, Calandriello L, et al.
ORBIT
2015;34(4):186-91.

INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE

Relationship between nocturnal intraocular pressure elevation and diurnal intraocular pressure level in NTG patients
Reviewed by: WSN
Vol 22 No 3
 

This group studies Korean normo-tension glaucoma (NTG) patients over a 24-hour period to assess if there was a relationship between nocturnal intraocular pressure (IOP) and diurnal IOP. They have previously suggested differences in diurnal IOP may have varying mechanisms of glaucomatous damage. Hence, they set out to assess if there was any difference in nocturnal IOP for patients with low diurnal IOP (mean IOP<15, n=70) and high diurnal IOP (mean IOP≥15, n=79). The study was prospective with age, axial length and disease severity matched patients and a power calculation was performed. The IOP measurements were taken using a single operator using a TonoPenXL which was validated with a previous study against Goldmann applanation tonometry (GAT). Eight measurements over a span of 24 hours were taken from the admitted patient. The study found nocturnal IOP in the low IOP group was significantly higher than that in the waking hours (12.8 vs 14.21 mm Hg P<0.001). This was not replicated in the high diurnal IOP group (16.33 vs 16.40 P=0.706). Furthermore, they found nocturnal IOP elevation was negatively correlated with axial length (p<0.001). Overall, the authors suggest the difference between their groups and nocturnal IOP elevation would mean a more tailored approach towards the timing of medication administration is beneficial in treating NTG in these groups. However, as the TonoPen readings were 95% of the time within 2mmHg of the GAT, it is hard to determine whether a 2mmHg nocturnal elevation is clinically significant.

Reference

Relationship between nocturnal intraocular pressure elevation and diurnal intraocular pressure level in normal-tension glaucoma patients.
Moon Y, Lee YJ, Jeong DW, et al.
INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE
2015;56:5271-9.

JAMA OPHTHALMOLOGY

Effect of change in retinal nerve fibre layer thickness on quality of life in patients with glaucoma
Reviewed by: Lona Jawaheer
Vol 22 No 3
 

The authors investigated the relationship between structural changes in glaucoma (retinal nerve fibre layer (RNFL) thickness) and quality of life (as measured by the NEI VFQ-25 questionnaire) over a period of time. Two hundred and sixty eyes of 130 patients were included, and baseline measurements included spectral-domain optical coherence tomography (SD OCT) and standard automated perimetry (SAP) at six month intervals, and the 25-item National Eye Institute Visual Function questionnaire (NEI VFQ-25) on a yearly basis. The patients were followed up for a mean (SD) period of 3.5 (0.7) years, during which a minimum of two NEI VFG-25 questionnaires were filled in, and five SPA and five SD-OCT measurements were done. They found that progressive loss of RNFL thickness was associated with a reduction in the NEI VEF-25 score, even after accounting for possibly confounding variables such as severity of disease at baseline, and progressive visual field loss. This is the first study that demonstrates a correlation between a structural change (progressive loss in RNFL thickness) and quality of life in glaucoma. The authors highlight that the progression of glaucoma is best measured using a combination of both structural and functional aspects. This study was limited by the relatively short period of follow-up, given the usually slowly-progressive nature of glaucoma. There is also the assumption that the changes progress linearly over time, although in fact they might progress at different rates at different stages of the disease process.

Reference

Association between progressive retinal nerve fiber layer loss and longitudinal change in quality of life in glaucoma.
Gracitelli CP, Abe RY, Tatham AJ.
JAMA OPHTHALMOLOGY
2015;133(4):384-90.

ACTA OPHTHALMOLOGICA

Evaluating ocular motor functions
Reviewed by: Nana Theodorou
Vol 22 No 3
 

Traditionally orthoptists are specialised in assessing ocular motor disorders. This article introduces the ocular motor score as a new clinical tool for screening and follow-up for children and young adults. The protocol consists of 15 tests such as stereoacuity, strabismus, convergence, saccades, etc that are scored with 0, 0.5 or 1. Forty children (aged 4-10 years) attending for routine clinical follow-ups took part to assess intra and inter rating agreement. One investigator completed all assessments and they were subsequently scored independently. Intrarater agreement was 88% with the lowest agreement seen for saccades and smooth pursuit. Inter-rater agreement was 80% with convergence and prism fusion test scoring lower. Scoring of ocular motor functions can be useful in monitoring follow-up measurements but it is unlikely that it will replace current practice.

Reference

Ocular Motor Score (OMS): a clinical tool to evaluating ocular motor functions in children.
Olsson M, Teär Fahnehjelm K, Rydberg A, et al.
ACTA OPHTHALMOLOGICA
2015;93:444-9.

ACTA OPHTHALMOLOGICA

The rarebit vision test for macular conditions
Reviewed by: Nana Theodorou
Vol 22 No 3
 

Rarebit testing is used to measure low degrees of neuro-visual damage and is available for free on the internet. It consists of a fixed bright light dot presented on a black background. During testing it is presented briefly at different locations centrally and peripherally. The size was fixed at 40×50 min of arc and the positions were varied at random within a 4.6×3.5-degree test field. The test task was to find the smallest rarebit number required to recognise the test digits. Thirty-seven patients with various stages of AMD and 25 control subjects participated in the evaluation, with an average age of 77 years. The results were compared with visual acuity measured using the Early treatment diabetic retinopathy study (ETDRS). Conventional acuity tests are not always sensitive in assessing macular functions in patients with AMD. The rarebit test appeared well suited for fine grading of vision in AMD. The authors conclude that this simple test is well suited for AMD patients. The simple set-up and lack of fixation demands made for practicable examinations of short durations.

Reference

New rarebit vision test captures macular deficits hidden to acuity tests.
Winther C, Frisén L.
ACTA OPHTHALMOLOGICA
2015;93:481-5.

CURRENT EYE RESEARCH

Meibomian gland alteration in patients with primary chronic dacryocystitis: An in vivo confocal microscopy study
Reviewed by: Jonathan C P Roos
Vol 22 No 3
 

Chronic dacryocystitis affects tear film functionality and can predispose to ocular surface disease, however the specific effect of chronic dacryocystitis on meibomian gland function has not been studied. This group therefore performed in vivo confocal microscopy in 28 patients’ eyes on the side affected by dacryocystitis and compared to their fellow eye and also to 27 healthy control patients. The participants also completed an Ocular Surface Disease Index questionnaire, had tear break up time measured and a Schirmer test. The confocal microscopy parameters included acinar unit density and diameter as well as periglandular inflammatory cell density. The study showed a significant reduction in acinar density, and raised inflammatory cells and shortest diameter of meibomian glands but no difference in their diameter – perhaps because they were obliterated vertically but blocked and therefore distended horizontally. The confocal microscopy parameters showed a strong correlation between dacrycocystistis and poor gland function. This study demonstrates that chronic dacryocystitis has a detrimental effect on meibomian gland function on the affected side, suggesting that treatment of underlying disease should be considered a priority.

Reference

Meibomian gland alteration in patients with primary chronic dacryocystitis: an in vivo confocal microscopy study.
Hong J, Yu Z, Cui X, et al.
CURRENT EYE RESEARCH
2015;40(8):772-9.

CURRENT EYE RESEARCH

Systemic rituximab immunotherapy in the management of primary ocular adnexal lymphoma single institutional experience
Reviewed by: Jonathan C P Roos
Vol 22 No 3
 

Ocular adnexal lymphomas constitute 2% of all non-Hodgkin’s disease and 5-15% of all extranodal lymphomas and are usually localised, low-grade and of B-cell origin. This opens them up to potential treatment with a systemic monoclonal antibody-based drug (rituximab) directed at CD20- a B-cell marker. Hitherto these lymphomas have been treated with surgical resection, cryotherapy, antiobiotics, interferon and radiotherapy. However, these treatments can cause ocular side-effects, in particular for the case of radiotherapy. Whilst rituximab has been used for lymphomas for many years, its use in primary ocular adnexal lymphoma is limited. This group therefore evaluated its systemic use in 10 consecutive patients with primary lymphoma. Patients were given 375mg/m2 iv three-weekly for 6-8 cycles. MRI and PET scanning were used to evaluate responses.  Patients were aged between 27 and 85 years and 90% presented with conjunctival involvement and without systemic manifestations. Thirty-six percent had complete remission without recurrence over 31 months from rituximab alone. None had ocular or systemic side-effects, however 64% required additional radiotherapy. The authors concluded that given the low rate of side- effects and significant response rate, rituximab may be considered an initial primary treatment for CD20 positive ocular adnexal lymphoma.

Reference

Systemic rituximab immunotherapy in the management of primary ocular adnexal lymphoma single institutional experience.
Tuncer S, Tanyildiz B, Basaran M, et al.
CURRENT EYE RESEARCH
2015;40(8):780-5.

EYE

Computerised tomography in ocular trauma patients
Reviewed by: Nana Theodorou
Vol 22 No 3
 

Ocular trauma can be common in military settings. This retrospective study looked into the relationship between the clinical effects of acute ocular and orbital blast trauma with the findings on computerised tomography (CT). This was a consecutive case series of 40 male soldiers with facial and / or suspected ocular injuries due to explosive blasts whilst on duty in Afghanistan. Of the 40 participants, 11 had unilateral and 16 bilateral injuries. Orbital and ocular CT images were performed and compared with actual clinical findings. No pathological findings were described in 37 of the 80 eyes imaged by orbital and ocular CT scans. These orbits were all found to be intact, or had minor trauma. All foreign bodies and penetrating eye injuries were successfully diagnosed by CT. For such patients, CT imaging proved a valuable tool in assessing ocular trauma quickly and enabling the necessary ophthalmic surgical intervention.

Reference

The role of computerised tomography in predicting visual outcome in ocular trauma patients.
Chaudhary L, Upendran M, Campion N et al.
EYE
2015;29:867-71.

EYE

Smartphone based visual acuity
Reviewed by: Nana Theodorou
Vol 22 No 3
 

Smartphone technology is becoming widely available to all age groups and settings. Apps using Snellen acuity charts are widely available and this study evaluated the equivalence of a smartphone-based visual acuity chart with a standard 6m Snellen visual acuity (6SVA) chart. The study was conducted in two parts: Part 1 consisted of a review of available apps on iPhone and part 2 of prospective comparative study between 6SVA and iPhone visual acuity using the ‘Snellen’ application on an Apple iPhone 4. For Part 1, 11 applications were identified, with accuracy of optotype size ranging from 4.4–39.9%. Eighty-eight patients from general medical and surgical wards in a tertiary hospital took part in Part 2. The mean difference in logMAR visual acuity between the two charts was 0.02 logMAR. The largest mean difference in logMAR acuity was noted in the subgroup of patients with 6SVA worse than 6/18, who had a mean difference of two Snellen visual acuity lines between the charts. We did not identify a Snellen visual acuity app at the time of study, which could predict a patient’s standard Snellen visual acuity within one line. There was considerable variability in the optotype accuracy of apps and care must be taken when using such tools. The authors’ mention that none are currently suitable for clinical use and additional validation is required for assessing patients with severe vision impairment.

Reference

The Eye Phone Study: reliability and accuracy of assessing Snellen visual acuity using smartphone technology.
Perera C, Chakrabarti R, Islam F, et al.
EYE
2015;29:888-94.

INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE

Exposure to atomic bomb radiation and age-related macular degeneration in later life
Reviewed by: Wai Siene Ng
Vol 22 No 3
 

This paper is one of the outcomes of the Adult Health Study; a cohort study of the atomic bomb survivors of Hiroshima-Nagasaki in Japan. It investigates the proposed association between pasty radiation exposure early in life and the presence of age-related macular degeneration (AMD) later in life among the survivors. AMD was diagnosed from fundus photography taken by a non-mydriatic digital camera and were assessed by a masked ophthalmologist. The assessment followed the Wisconsin AMD grading system, modified for the Blue Mountains Study. Individual eye radiation dose was estimated with a dosimetry system (DS02) and weighted in data analysis. Nearly a quarter of the total sample of participants was excluded due to participants not agreeing with the examination or having ungradable photo quality. There were 1824 subjects analysed with a mean age of 73.8±6.7 years and 197 AMD patients. 43.6% had less than 0.005 Gy and 4.8% had more than 2 Gy exposure. The prevalence of AMD did not show any radiation-related trends. However, as there was a high proportion of the cohort excluded due to poor quality fundus image, it is possible there is an element of selection bias from radiation-related opacity in lens. Furthermore, the study lacked matched controls and given the low number of subjects diagnosed with AMD, it may have attributed to the results of the study showing no statistically significant associations between radiation exposure early in life and the prevalence of AMD in later life among the cohort.

Reference

Exposure to atomic bomb radiation and age-related macular degeneration in later life: The Hiroshima-Nagasaki atomic bomb survivor study.
Itakura K, Takahashi I, Nakashima E, et al.
INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE
2015;56:5401-6.

JAMA OPHTHALMOLOGY

Analysis of risk factors for intraocular pressure rise following insertion of fluocinolone acetonide injection in uveitic patients
Reviewed by: Lona Jawaheer
Vol 22 No 3
 

For this study, the authors analysed the pooled data from three phase2b / 3 multi-centre randomised controlled trials carried out over three years. Included patients had undergone at least one of the following treatments: 1) systemic therapy (corticosteroid / immunosuppressant for at least three months) 2) two or more subtenon’s injections of steroid in the six months prior to enrolment, or 3) systemic steroid or subtenon’s steroid injection on at least two occasions over the six months prior to enrolment. The treatment arm included 290 eyes that received an implant of 0.59-mg FAI, and the control arm included 351 eyes that were treated with topical / systemic steroids or other immunosuppressants. The patients were followed up at pre-planned intervals over three years. Absolute values of IOP and IOP elevations were measured, as well as the percentage of eyes that required topical treatment or surgical treatment for raised IOP. A greater proportion of eyes in the treatment arm developed IOP rises of 10mmHg and absolute IOP of 30mmHg (65.1% versus 17.1%, hazard ratio (HR) 5.80). Risk factors between the two groups were compared and a younger age, male sex and phakic status were found to be significantly associated with a higher risk of IOP rise, while no such association was shown for race, disease severity at time of enrolment, and location of uveitis. A greater progression in optic disc cupping (significant) and in mean deviation in Humphrey’s Visual Field (non-significant) were also noted in the treatment group over the observation period. This study confirms the high incidence of raised IOP following treatment with FAI. It indicates the need for patient selection for this treatment, and for close follow-up and adequate IOP management to prevent development or worsening of glaucoma. Because of the multi-centre nature of this study, there is likely to have been some variability in the diagnosis and management of glaucoma-related damage.

Reference

Risk factors associated with intraocular pressure increase in patients with uveitis treated with the fluocinolone acetonide implant.
Parekh A, Srivastava S, Bena J, et al.
JAMA OPHTHALMOLOGY
2015;133(5):568-73.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Collamer lenses for accommodative ET
Reviewed by: Fiona Rowe
Vol 22 No 3
 

Posterior chamber phakic intraocular lense (IOL) implantation was used to treat patients with accommodative esotropia with the goal of eliminating hyperopia and producing orthophoria. Three patients (six eyes) aged 18-22 years had an average follow-up of 17 months ±6.24. The mean preoperative spherical equivalent cycloplegic refraction was 6.04D ±0.53 and postoperative refraction of 0.41D ±0.21. This was stable over the follow-up period. All three achieved orthophoria or microesophoria postoperatively. Postoperative corneal oedema occurred in one case which recovered rapidly. One patient complained of postoperative glare which reduced over time. Preliminary results show that IOL implantation for accommodative esotropia is safe, effective, predictable and stable with low incidence of postoperative complications and positive patient satisfaction. Further large scale studies are recommended.

Reference

Treatment of adults with accommodative esotropia using implantable collamer lenses.
Shi M, Jiang H, Ye Y, Chen B.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:31-6.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Expert vs. non expert grading of ROP from digital video images
Reviewed by: Fiona Rowe
Vol 22 No 3
 

The primary purpose of this study was to determine whether digital video images of the retina obtained using an indirect ophthalmoscope imaging system could be accurately graded for zone and stage of retinopathy of prematurity (ROP) and the presence of plus or pre-plus disease. The secondary aim was to determine whether these digital retinal video images could be accurately graded to detect the presence of disease (type I ROP) requiring treatment by comparing two predefined criteria for referral. The first criterion for referral was the presence of pre-threshold disease, pre-plus disease or plus disease. The second criterion was the presence of only pre-plus or plus disease. The study included 114 infants with median gestation age of 26 weeks (23-33) and median birth weight of 840g (450-2300). Experts judged 60% of images to have fair or good image quality versus 55% of non-experts. Of these images, the experts and non-experts correctly identified zone (75 vs. 74%), stage of ROP (75 vs. 40%) and presence of pre-plus or plus disease (79%). Sensitivity of grading images for presence of pre-threshold, pre-plus or plus disease was 100% for experts and non-experts. Specificity was 77 and 82%. The non-experts had a more difficult time identifying the stage of ROP, particularly stage 3. Neither grader misclassified zone by more than one zone. The authors conclude that high quality retinal video images can be read with high sensitivity and specificity to screen for type I ROP.

Reference

Evaluation of the accuracy of grading indirect ophthalmoscope video images for retinopathy of prematurity screening.
Prakalapakorn S, Wallace DK , Dollard RS, Freedman SF.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:85-92.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

IO surgery
Reviewed by: Fiona Rowe
Vol 22 No 3
 

The purpose of this paper was to evaluate the efficacy of a new surgical technique in reducing IOOA consisting of suturing the muscle to the sclera at the Gobin point with tendon sparing and using a micro incision to minimise related tissue trauma. Eight patients aged 5-51 years were included. At four months postoperative the mean angle reduced to 8PD exotropia in five patients with a V-exotropia. One patient with unilateral IOOA had reduced from 18 to 3PD vertical deviation. Two patients with infantile esotropia had complete resolution of elevation in adduction with no vertical imbalance. All had improvement in lateral incomitance. The authors propose the technique as simple, safe, reversible and modular in terms of suturing. They propose additional benefits of little risk to developing vorticose haemorrhage or macular damage, no errors in IO muscle hooking and no risk of anti-elevation syndrome.

Reference

New surgical intervention for the weakening of the inferior oblique muscle: equatorial scleral anchor.
Tomarchio S, Sabetti L, Tomarchio M, Berarducci A.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:58-60.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Management of congenital NLD obstruction
Reviewed by: Fiona Rowe
Vol 22 No 3
 

The authors evaluated changes in management of congenital nasolacrimal duct obstruction (CNLDO) by surveying 1495 American Association for Pediatric Ophthalmology & Strabismus (AAPOS) members. The survey consisted of 21 multiple choice questions with anonymised return. Responses were received from 127 members and six were excluded as potentially biased. Eighty-four percent were completed by North American members and 16% by international members which was reflective of the AAPOS organisational membership. Ninety-five percent regularly treat CNLDO. For treatment in the first year of life 45% perform the Crigler manoeuver on the initial visit for infants younger than six months. Eighty-two percent instruct carers to massage the duct. Seventeen percent offer office probing but this is significantly more for those with >10 years’ experience. Surgical treatment includes 79% recommending surgery from 13 months of age for unresolved cases, and 12% for infants aged 10-12 months. Of that 79% chose probing as their primary treatment. In children with first surgery at age two years, 53% chose non-probing procedures. For children aged three years at first procedure, 67% chose non-probing procedures. For failed probing, most opted for silicone intubation with or without balloon dacryoplasty. With silicone intubation, 64% preferred monocanalicular tubes typically left in place for three to four months. For bicanalicular tubes, most were removed in the office and the remainder in the operating room. With regard to risk of amblyopia, 91% regularly check refraction at the initial visit and 45% recheck when aged one to two years. This study found a striking lack of consensus among ophthalmologists.

Reference

Congenital nasolacrimal duct obstruction: common management policies among pediatric ophthalmologists.
Dotan G, Nelson LB.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:14-9.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Postop improved fusion and stereopsis in IDEX
Reviewed by: Fiona Rowe
Vol 22 No 3
 

This study aimed to evaluate changes in binocular visual function in patients with different ages before and after surgery to explore the optimal timing of intermittent exotropia surgery. The study comprised 28 females and 25 males. Fifty-three patients were split to three groups of <7 years, 7-13 years and >13 years. Median age was 6.07, 10.82 and 16.298 years respectively. They were examined preoperatively and at two and six weeks postoperatively. Thirty two percent had a family history of strabismus. Thirty-eight percent had their strabismus detected during routine physical examination. The angle of deviation at near and distance significantly increases with older age with median angles of 55, 45 and 85PD respectively for the three groups at near fixation and 37.5, 40 and 80PD at distance fixation. Near stereoacuity improved significantly as did distance stereoacuity. Peripheral and central fusion improved postoperatively and improvement was noted across all age groups. The authors propose that surgery for intermittent exotropia can be postponed appropriate to the case.

Reference

Improvement in fusion and stereopsis following surgery for intermittent exotropia.
Feng X, Zhang X, Jia Y.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:52-7.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Refocus on children programme results
Reviewed by: Fiona Rowe
Vol 22 No 3
 

The authors describe the logistics and results of the refocus on children programme for the 2012-13 school year. The aim of the programme was to help school nurses provide access to comprehensive vision care and reduce unnecessary visual loss or impairment. The programme was designed for children in 23 low income schools. The Plusoptix screener was used and 2750 children were successfully screened. Seven hundred and forty-one were referred (27%). Consent for further examination was obtained for 419 children and 192 were given glasses. There was a 49% response rate to the request for feedback from teachers for these children. Children receiving glasses typically wore them regularly. Seventy percent of teachers reported that children liked their glasses. Positive comments from teachers included reduced squinting, better vision, improved academic performance, improved child focus on lessons, improved participation and interaction. Negative comments included children being embarrassed to wear glasses, taking poor care of glasses and glasses being used as a toy. Overall the study examined 56% of children referred. As the process was completed at school, the students received the support of the entire team which helped with wearing new glasses. Half of the children referred needed glasses.

Reference

Combining automated vision screening with on-site examinations in 23 schools: refocus on children program 2012 to 2013.
Peterseim MM, Papa CE, Parades C et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:20-4.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Silicone rod for ptosis surgery
Reviewed by: Fiona Rowe
Vol 22 No 3
 

The authors report their results and complications associated with the use of silicone rod for frontalis suspension lid surgery. This was a retrospective study of 38 eyes (25 patients) with six months follow-up. The group included 19 males and six females aged 3-21 years (mean 10.68 ±6.26). Adequate cosmetic correction was attained in 34 eyes (89%). Four eyes had undercorrection and one eye had late recurrence of ptosis due to sling slippage. Five eyes had significant lid lag and lagophthalmos, three had suture granuloma on the forehead, three with sling exposure and one with bilateral chronic eye lid oedema. The authors report the silicone rod to be safe with the advantage of allowing complete eyelid closure because of its elasticity. It is deemed useful in patients with poor Bell’s phenomenon and dry eye. However, it is not without complications.

Reference

Results and complications of silicone frontalis sling surgery for ptosis.
Bansal RK, Sharma S.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:93-7.

NEURO-OPHTHALMOLOGY

Association between neuro-ophthalmology signs and chronic ataxia in children
Reviewed by: Claire Howard
Vol 22 No 3
 

Neuro-ophthalmological signs (N-OS) occur commonly in children with chronic ataxia. This study describes the N-OS and their frequencies, in general and by specific disease aetiology in paediatric patients with chronic ataxia. In total, 184 patients under the age of 17 years with chronic ataxia were identified. The study found 214 N-OS in 115 patients and the details of these signs along with patient diagnosis are recorded in detail by the authors. Strabismus was present in 29.3% of patients, nystagmus 27.7%, impaired smooth pursuit 23.4%, hypometric saccades 10.3%, decreased visual acuity 9.2%, abnormal optic discs 8.7%, abnormal pupillary examination 2.7%, hypermetric saccades 2.2%, impaired ductions 1.6% and abnormal visual fields in 1.1% of patients. Some N-OS were found more commonly in specific conditions, for example strabismus was most common following hypoxic-ischaemic encephalopathy after birth. The study findings are limited due to its retrospective nature. The study findings highlight the importance of a thorough examination of the visual and ocular motor systems. The findings from this ophthalmological assessment may aid in the assessment of these challenging children.

Reference

Neuro-ophthalmological findings in children and adolescents with chronic ataxia.
Salman MS, Chodirker BN.
NEURO-OPHTHALMOLOGY
2015;39(3):125-31.

NEURO-OPHTHALMOLOGY

Visual outcomes, visual fields and optical coherence tomography in paediatric craniopharyngioma
Reviewed by: Claire Howard
Vol 22 No 3
 

This study reviews the visual outcomes of ten patients under the age of 18 years with craniopharyngioma. The paper also reviews the correlation between visual field (VF) testing and optical coherence tomography (OCT) examination and evaluates the role of OCT for the prediction of visual outcomes after surgery. All children underwent surgery for the removal of the tumour with one child also receiving adjuvant radiotherapy. To date, the children have required between one and four procedures to control the tumour (mean of two procedures per child). The best kappa concordance coefficients between VF and OCT parameters of atrophy were obtained for the ganglion cell (GC) thickness and the mean retinal nerve fibre layer (RNFL) thickness. The agreement between GC colour maps and VF defects were good. In conclusion, optic nerve compression may be detected by RNFL measurement and GC analysis, and this may be useful in the prediction of visual recovery. It could also be used in the evaluation of uncooperative patients to predict visual damage.

Reference

Visual outcomes, visual fields and optical coherence tomography in paediatric craniopharyngioma.
Mediero S, Noval S, Bravo-Ljubetic L, et al.
NEURO-OPHTHALMOLOGY
2015;39(3):132-9.

NEW ENGLAND JOURNAL OF MEDICINE

Intensive diabetes therapy and ocular surgery in type 1 diabetes
Reviewed by: Jonathan C P Roos
Vol 22 No 3
 

The Diabetes Control and Complications Trial (DCCT) ran between 1983 and 1993 and showed that intensive glycaemic control was beneficial in reducing diabetic retinopathy in type 1 patients. There was a 76% reduction in onset of retinopathy and a 52% reduction in progression. A majority of these patients (1375) were then enrolled on the Epidemiology of Diabetes Interventions and Complications (EDIC) Trial, a follow-on study which showed that the effect of a period of good glycaemic control could still be measured after 18 years in what has been termed ‘metabolic memory’. The authors now report further results from this patient cohort as regards their self-reported need for ocular surgery. Over a median follow-up period of 23 years, the authors report that only 8.9% of the 711 patients in the intensive glycaemic control group had ocular surgery, compared to 13.4% of the 730 assigned to conventional therapy (p<0.001). This included a reduced risk of requiring cataract surgery, vitrectomies and retinal detachment surgery. The study authors concluded that intensive therapy for patients with type 1 diabetes reduces the risk of requiring ocular surgery. However, there was no statistical difference in the need for oculoplastic surgical procedures, glaucoma surgery, enucleation, posterior YAG capsulotomy or cornea related operations. Though this is a high quality randomised cohort study, it does not include patients with type II diabetes and so it is not possible to know whether the results apply also to those patients, though it would seem highly likely, as the beneficial effect of surgery could be fully accounted for by the reduction in HbA1c levels.

Reference

Intensive diabetes therapy and ocular surgery in type 1 diabetes.
The DCCT/EDIC Research Group.
NEW ENGLAND JOURNAL OF MEDICINE
2015;372:1722-33.

NEW ENGLAND JOURNAL OF MEDICINE

Long-term effect of gene therapy on Leber’s congenital amaurosis
Reviewed by: Jonathan C P Roos
Vol 22 No 3
 

After reporting the first successful gene therapy results for RPE65 deficiency in three patients in a brief report in 2008, the same team from London now report the results of 12 patients followed up for three years after transfection. As part of a phase 1-2 open label trial, four patients were given a lower dose of adeno-associated virus vector carrying RPE65, whilst eight were given a higher dose. Unfortunately, only six patients showed some improvement in retinal sensitivity but the effect was not long-lasting and after a peak at around a year or so post transfection, there was a decline. ERG did not detect improvement in retinal function. Two patients had a significant deterioration in vision and three developed uveitis. These results could therefore be seen as disappointing after the early promise. However, this trial provides some valuable lessons. First, those with higher dose transfection were more likely to have an improvement, and second, an improvement is possible but may require repeat treatment for a sustained effect. In order to investigate the dose-response relationship between vector and retinal improvement the same group performed a parallel study in Briard dogs which carry an RPE65 mutation. The team found that improvements measurable by ERG could be achieved, but that this was dose dependent. The implication of course is that there is a different amount of RPE65 required in different species to maintain the visual cycle and if better promoters can be developed which increase expression there is hope that this can become a successful therapy in the future.

Reference

Long-term effect of gene therapy on Leber’s congenital amaurosis.
Bainbridge JW, Mehat M, Sundaram S, et al.
NEW ENGLAND JOURNAL OF MEDICINE
2015;372:1887-97.

OCULAR IMMUNOLOGY AND INFLAMMATION

Lucentis for pseudophakic CMO
Reviewed by: Saruban Pasu
Vol 22 No 3
 

Pseudophakic cystoid macular oedema (CMO) develops angiographically in up to 20-30% after uneventful phacoemulsification. This study aimed to evaluate the potential efficacy and safety of intravitreal ranibizumab in patients with pseudophakic CMO after cataract surgery. Seven eyes were included in this retrospective observational study. All patients were refractory to previous treatment with nonsteroidal anti-inflammatory drugs (NSAIDs) and steroids for at least three months. All patients received at least one intravitreal injection of 0.5mg ranibizumab. Patients received reinjections in case of recurrence of CMO (decrease of best corrected visual acuity (BCVA) >2 Snellen lines or as an increase in central retinal thickness (CRT) >100um on OCT). Both mean BCVA and mean CRT differed significantly pre and post injection. All patients presented resolution of macular oedema in about one month after intravitreal injection. One patient had recurrence of CMO three months after injection. No observable ocular side-effects were found in all patients. In line with other studies these results demonstrated that intravitreal ranibizumab is safe and effective in patients with pseudophakic cystoid macular oedema, providing a significant improvement in BCVA as well as a decrease in retinal thickness on OCT. These favourable and promising results support the need for further randomised case-control studies with large sample size to evaluate the safety and efficacy of intravitreal ranibizumab for this clinical entity.

Reference

Intravitreal ranibizumab for the treatment of Irvine-Gass Syndrome.
Mitropoulos P, Chatziralli I, Peponis V, et al.
OCULAR IMMUNOLOGY AND INFLAMMATION
2015;23(3):225-31.

OCULAR IMMUNOLOGY AND INFLAMMATION

Smoking and Behçet’s disease
Reviewed by: Saruban Pasu
Vol 22 No 3
 

This study aimed to investigate the relationship between smoking and prognosis of ocular Behçet’s disease (BD). Records of 202 patients with ocular features of BD were reviewed from a Turkish hospital. Patients were divided into two groups according to their smoking habits; in group 1, 72 patients were current smokers, and in group 2, 130 were nonsmokers. Smoking status was not found to be associated with the location of inflammation. The average time to resolution and time of recurrences was similar in both groups. Previous studies have reported that stopping smoking could activate or aggravate the disease, especially mucocutaneous lesions, and increase the risk of cystoid macular oedema (CMO). Data from this current report showed that being a smoker is not a statistically significant risk factor for CMO in patients with ocular BD. The authors conclude that smoking does not have a negative effect on the clinical findings and prognosis of uveitis in BD.

Reference

Is smoking a risk factor in ocular Behçet’s disease.
Bilgin AB, Turkoglu EB, Ilhan HD, et al.
OCULAR IMMUNOLOGY AND INFLAMMATION
2015;23(4):283-6.

OCULAR IMMUNOLOGY AND INFLAMMATION

Uveitis in the elderly
Reviewed by: Saruban Pasu
Vol 22 No 3
 

This study from Turkey evaluated the causes and clinical characteristics of uveitis in elderly patients. Data from 90 eyes of 68 patients aged 60 years and older were reviewed. Anterior uveitis was present in 75% (33% of these had keratouveitis), intermediate uveitis in 4.4%, posterior uveitis in 7.3% and panuveitis in 13.2%. With respect to causes: 33.8% were idiopathic, herpetic anterior uveitis in 33.8%, Fuchs in 6.8%, HLA-B27 associated uveitis in 5.8%, toxoplasmosis in 2.9%, multifocal choroiditis in 2.9%, CMV retinitis in 1.4% and VKH in 1.4%. Elevated IOP was found to be more common in herpetic anterior uveitis. Visual acuity improved by at least two Snellen lines in 27.7%, remained unchanged in 66.6% and decreased in 5.5%. Although endemic to the country, Behçet’s was not seen in this age group, similarly no cases of sarcoidosis related uveitis were seen. The authors excluded cases of masquerade syndrome, but go on to explain that primary intraocular / vitreoretinal lymphoma presents in 1.5-5.3% of cases of uveitis in this age group. The effects of referral or selection bias, varying diagnostic criteria, and lack of uniform nomenclature classification for uveitis types and causes make comparison of epidemiological data from different populations and regions difficult.

Reference

Clinical and demographic characteristics of patients with uveitis starting later in life.
Nalcaciglu-Yukeskkaya P, Ozdal P, Yazici A, et al.
OCULAR IMMUNOLOGY AND INFLAMMATION
2015;23(4):304-10.

OPHTHALMIC EPIDEMIOLOGY

Lower postoperative scar height is associated with increased postoperative trichiasis one year after bilamellar tarsal rotation surgery
Reviewed by: Jonathan C P Roos
Vol 22 No 3
 

Bilamellar tarsal rotation has been a key component of the WHO SAFE approach to blindness from trichiaisis (surgery, antibiotics, facial hygiene, environment). The World Health Organisation (WHO) manual describes the procedure as a full thickness blepharotomy placed 3.0mm above and parallel to the eyelid margin and then rotated and reattached with mattress sutures. However, the recurrence rate of trichiasis following this procedure is 30-40% after one year – an unacceptably high level. For this reason this multinational team stratified surgical success by postoperative scar height. One hundred and forty-five sequential patients were reviewed one year following their surgery and their scar height measured externally and on tarsal conjunctiva at three locations in the upper eyelid. Seventy-seven lids (31%) had postoperative recurrence of trichiasis – most often centrally.  There was an indirect correlation between scar height and recurrence rate, until 4.5mm height, at which point the rate levelled off. Using multivariate analysis severe disease and scar <4.5mm were both associated with postoperative trichiasis. The authors tentatively suggest that perhaps the WHO guidance of 3.0mm blepharotomy height be reviewed as this could offer significant cost-savings and patient benefit.

Reference

Lower postoperative scar height is associated with increased postoperative trichiasis 1 year after bilamellar tarsal rotation surgery.
Merbs SL, Oktavec KC, Munoz BE, et al.
OPHTHALMIC EPIDEMIOLOGY
2015;22(3):200-7.

OPHTHALMIC EPIDEMIOLOGY

Task shifting for eye care in Eastern Africa
Reviewed by: Jonathan C P Roos
Vol 22 No 3
 

More than eight million people suffer with trichiasis due to trachoma globally, but less than 160,000 receive surgery per year even though “S” is a key aspect of the elimination of blindness due to trachoma as part of the WHO “SAFE” approach. In order to meet the shortfall, general nurses have been trained to perform this surgery in a term known as task shifting. This study sought to determine the productivity and attrition of such general nurses trained in trachomatous trichiasis surgery in three East African countries. The team took the approach of a three year cohort study of trichiasis surgeons. The response rate by the surgeons to the questionnaire was good: 86%. Only 16.1% of the 222 surgeons performed more than 50 such operations per year. Twenty-eight percent had left their area and no longer performed the surgery over three years – a high attrition rate. The authors found that having been trained by an experienced trainer, being supervised and having an outreach programme with more than three surgical sets were all associated with high productivity and low attrition. The authors concluded that overall productivity was too low and attrition too high to warrant training of general nurses for trachomatous trichiasis surgery. Instead they suggest that a different approach must be sought to address the surgical need presented by trachoma and suggest that this might include a complete plan for provision of surgery. This might include multiple surgical packs, outreach programmes, continuous support, supervision and training. There remains currently, a large and unmet need for the WHO to achieve its 2020 goals of elimination of blindness due to trachoma.

Reference

Task shifting for eye care in Eastern Africa: general nurses as trichiasis surgeons in Kenya, Malawi and Tanzania.
Gichangi M, Kalua K, Barassa E et al.
OPHTHALMIC EPIDEMIOLOGY
2015;22(3):226-30.

OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY

Biodegradable plates in lateral orbitotomy surgery
Reviewed by: James Hsuan
Vol 22 No 3
 

This is a description of a new method for fixating the bone flap during a lateral orbitotomy. The technique involves the use of an absorbable lactide plate. This is warmed in a water bath to allow trimming and moulding to the correct contour, and then bone holes are drilled in line with holes in the plate. Biodegradable lactide pins hold the plate securely to the bone and are inserted using an ultrasonic handpiece. This drives the pins into the bone and simultaneously melts the pin heads which then fuse with the plate. Ten patients underwent bone fixation using this technique with an average follow-up time of 12.9 months. Three patients developed postoperative oedema and inflammation, which was treated with oral steroids, but in one of these the inflammation persisted for 10 months. However, no patient required removal of the plate, and there were no visual or ocular motility complications. Biodegradable plates have been used extensively in maxillo-facial surgery, but have not been described previously for lateral orbitotomy closure. The main drawbacks are lack of strength compared to titanium, and inflammation. The former is unlikely to be a major concern given the lack of load bearing of the lateral rim, but the inflammatory reaction is more worrisome. This series had a high rate of 30%, but the numbers were small and other larger series have reported lower rates of this complication. The cost is comparable to titanium plating, but more expensive than suturing. Cosmetically the lactide plates have a thinner profile than titanium, and there is no need for further surgery to remove them. There is a learning curve for the ultrasonic pin placement, but once mastered the technique is no more difficult or time-consuming than titanium plating.

Reference

Biodegradable fixation of the orbital rim after lateral orbitotomy.
Davies BW, Mollman RA, Gonzalez MO, et al.
OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY
2015;31:287-9.

OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY

Ointment related granulomas post-blepharoplasty
Reviewed by: James Hsuan
Vol 22 No 3
 

This is a retrospective review of eight patients who developed granulomatous masses after lower lid blepharoplasty. All patients had sutureless bilateral trans-conjunctival surgery, and lubricating ointment was instilled into the inferior fornix postoperatively for two days. Painless lower lid masses developed between nine days and 10 months following surgery. In all but one patient this was bilateral. Seven patients were treated with intra-lesional steroid with or without oral steroids and antibiotics, and five patients required surgical excision before resolution was achieved. Histopathology showed large lipid-laden areas surrounded by a foreign body giant cell reaction, consistent with petrolatum induced granulomatous inflammation. This is an interesting case series of a relatively rare complication of blepharoplasty surgery. Avoidance of the complication by closing the wound is discussed, but the use of sutures is not without risk, and they can occasionally also cause significant inflammation and lid retraction. It may be preferable to avoid the use of petrolatum ointments when entrapment within the tissue is a possibility. Although the authors suggest initial treatment should be with intra-lesional steroid, recurrence following injection was common and the majority of their patients required surgical debulking before resolution. There were no recurrences following surgery.

Reference

Ointment granulomas following sutureless transconjunctival blepharoplasty: Diagnosis and management.
Belinsky I, Patel P, Charles NC, Lisman RD.
OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY
2015;31:282-6.

OPHTHALMIC RESEARCH

Inner nuclear layer of the retina showing increase in thickness in diabetic macular oedema
Reviewed by: Bheemanagouda Patil
Vol 22 No 3
 

Diabetic retinopathy is one of the leading causes of blindness in the developed world. With optical coherence tomography (OCT), it has become possible to image the retina in vivo and to measure retinal oedema by measuring retinal thickness (RT) with high accuracy. The purpose of this study was to identify the retinal layer predominantly affected in eyes with subclinical and clinical macular oedema in type 2 diabetics. One hundred and ninety-four patients with mild nonproliferative diabetic retinopathy (ETDRS levels 20/35) were examined with Cirrus spectral-domain OCT at the baseline visit. Automated segmentation of the retinal layers of the eyes with subclinical and clinical macular oedema was compared with a sample of 31 eyes from diabetic patients with normal OCT and an age-matched control group of 58 healthy eyes. From the 194 eyes in the study, 62 had subclinical macular oedema and 12 had clinical macular oedema. The highest increases in RT were found in the inner nuclear layer (INL; 33.6% in subclinical macular oedema and 81.8% in clinical macular oedema). Increases were also found in the neighbouring layers. Thinning of the retina was seen in the retinal nerve fibre, ganglion cells and inner plexiform layers in the diabetic eyes without macular oedema. The increase in RT occurring in diabetic eyes with macular oedema is predominantly located in the INL but extends to neighbouring retinal layers indicating that it may be due to extracellular fluid accumulation.

Reference

Retinal layer location of increased retinal thickness in eyes with subclinical and clinical macular edema in diabetes type 2.
Bandello F, Tejerina AN, Vujosevic S, et al.
OPHTHALMIC RESEARCH
2015;54:112-7.

STRABISMUS

Prism cover test variances
Reviewed by: Fiona Rowe
Vol 22 No 3
 

The purpose was to establish the inter-examiner variability and agreement between more than two examiners assessing children and adult patients. The study involved four experienced examiners. The alternate prism cover test (APCT) was conducted at near and distance in 41 subjects with horizontal strabismus (21 male and 20 female) with a median age of 12 years (3-74). Twenty-five were exo and 16 eso deviations. Twenty-two were manifest, 13 intermittent and six latent deviations. Inter-examiner variability between APCT measurements performed by two examiners ranged from 6.9 to 12.5PD dependent on the examiner pair and fixation distance. Slightly larger variances were found for near versus distance fixation. A value of 10PD is suggestive of real change at near and 9PD for distance. Angle of deviation, test distance and age had no significant influence on variations.

Reference

Inter-examiner variability and agreement of the alternate prism cover test (APCT) measurements of strabismus performed by four examiners.
de Jongh E, Leach C, Tjon-Fo-Sang MJ, Bjerre A.
STRABISMUS
2014;22:158-66.

BRITISH JOURNAL OF OPHTHALMOLOGY

Myopic choroidal neovascularisation
Reviewed by: Jonathan Chan
Vol 22 No 2
 

This is a review article summarising the latest myopic CNV (choroidal neovascularisation) literature in the clinical experience and management outcomes for recommendation algorithm. The aetiology of the myopic CNV was discussed by the authors under the heading of the heredo-degenerative and haemodynamic theories for the development of myopic CNV. The diagnosis of myopic CNV was based on the clinical examination, including fundal biomicroscopy, fluorescein angiogram and optical coherence tomography (OCT). The majority of the myopic CNV presents as a classic pattern on the fluorescein angiogram. On OCT imaging the majority represents a highly refractive area above the retinal pigment epithelium – type 2 CNV with minimal subretinal fluid. Fundus autofluoresence showed the increase in the accumulative lipofuscin within the retinal pigment epithelium. Lucentis (ranibizumab) is the only licensed anti-VEGF therapy for treatment of myopic CNV. Avastin (bevacizumab) is not approved for intraocular use and evidence on its safety and efficacy profile is limited. Aflibercept (Eylea) for myopic CNV is undergoing phase III, multicentre, randomised trial at present. Recent reports on Eylea indicate sustained best corrected visual acuity gains of up to 12 months. The authors recommend a treatment algorithm for myopic CNV. After initial assessment prompt treatment with a single intravitreal injection of anti-VEGF therapy is recommended due to the superior efficacy of anti-VEGFs over other treatment modalities. After the initial injection, the patients will be monitored monthly for months one and two and then at least three-monthly in the first year. If patients have positive activity or visual loss then they will have a repeat injection. After one year, the monitoring frequency should be established by the retinal specialist in consultation with the patient and the patient should be advised to return if they experience any drop in vision.

Reference

Myopic choroidal neovascularisation: current concepts and update on clinical management.
Wong TY, Ohno-Matsui K, Leveziel N, et al.
BRITISH JOURNAL OF OPHTHALMOLOGY
2015;99:289-96.

BRITISH JOURNAL OF OPHTHALMOLOGY

Screening for ROP using wide-angle digital retinal photography by non-ophthalmologists
Reviewed by: Jonathan Chan
Vol 22 No 2
 

This is a systematic review article to evaluate the accuracy of digital retinal photography (DRP) performed by trained personnel (non-ophthalmologists) in diagnosing clinically significant retinopathy of prematurity (ROP). The authors used search engines including Medline, EMBASE, CINAHL and Cochrane databases. There were in total six studies within the inclusion criteria (three prospective; N=120, three retrospective, N=579). All the eligible studies were assessed using the quality assessment of diagnostic accuracy (QUADAS)-2, an evidence-based tool for the assessment of the quality in systematic reviews of diagnostic accuracy studies. Because of the heterogeneity of the studies, data could not be pooled to derive single-effect size estimates for sensitivity and specificity. However, the included studies reported sensitivity of 45.5-100% with the majority being more than 90%; specificity 61.7-99.8% with the majority being more than 90%, positive predictive value was 61.5-96.6% and negative predictive value was 76.9-100% for diagnosing clinically significant ROP. The authors concluded that the ROP imaging diagnostic accuracy must be established in a larger sample size in prospective multicentre trials where the ROP is compared simultaneously against the performed reference of standard binocular indirect ophthalmoscopy examination.

Reference

Screening for retinopathy of prematurity (ROP) using wide-angle digital retinal photography by non-ophthalmologists: a systematic review.
Athikarisamy SE, Patole S, Lam GC, et al.
BRITISH JOURNAL OF OPHTHALMOLOGY
2015;99:281-8.

CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY

Choroidal and RNFL thickness in patients with OSAS
Reviewed by: Anjali Gupta
Vol 22 No 2
 

In obstructive sleep apnoea syndrome (OSAS), hypoxia secondary to repetitive apnoeic episodes leads to blood pressure variations and haemodynamic changes. There is also intermittent activation of the sympathetic system when the patient is aroused from sleep during apnoeic episodes. OSAS is known to be associated with many ophthalmological disorders such as floppy eyelid syndrome, glaucoma, non arteritic ischaemic optic neuropathy, central serous chorioretinopathy and papilloedema. However, little is known about the effects of OSAS on the choroid, one of the most vascularised tissues in the body. The aim of this study was to compare the choroidal thickness (CT) and retinal nerve fibre layer (RNFL) thickness in patients with OSAS to healthy controls. Ninety-two eyes of patients with OSAS and 32 eyes of age and body mass index (BMI) matched healthy controls were included in this study. OSAS patients were further divided into mild, moderate and severe groups according to their apnoea hypopnea index (AHI) values. All patients and controls were imaged with the RTVue SD-OCT system from 10am to 12am after pupil dilation. Measurements were taken for peripapillary RNFL thickness and macular CT and compared between groups. Results showed that the severe OSAS group had significantly thinner CT than the mild OSAS group at 3mm nasal to the fovea. The control group had significantly thicker CT 1.5mm and 3mm nasal to the fovea compared with the severe OSAS group. The severe and moderate OSAS groups had significantly thinner nasal RNFL measurements than controls. The severe OSAS group also had significantly thinner superior RNFL measurements than the controls. The authors conclude that patients with OSAS have choroidal structural alterations that may have significance on the pathophysiology of the ophthalmic disorders associated with OSAS.

Reference

Evaluation of the macular choroidal thickness using spectral optical coherence tomography in patients with obstructive sleep apnea syndrome.
Bayhan HA, Bayhan SA, Intepe YS, et al.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2015;43:139-44.

CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY

Twenty-four hour IOP patterns in patients with thyroid eye disease (OO/GL)
Reviewed by: Anjali Gupta
Vol 22 No 2
 

Elevated IOP in patients with thyroid eye disease (TED) can be caused by restriction and compression of the globe by enlarged extraocular muscles, elevated episcleral venous pressure and increased mucopolysaccharide deposition in the trabecular meshwork. Although previous studies have investigated the relationship between IOP and TED, there have been no previous studies that have evaluated the 24-hour IOP rhythms in patients with TED. The purpose of this study was to evaluate the safety and tolerability of a contact lens sensor (CLS) to measure IOP in patients with TED and to describe the 24h IOP patterns in this group of patients. The CLS is a high oxygen permeable soft contact lens with an embedded microprocessor which can measure IOP. The device is based on the approach that changes in corneal curvature and circumference are assumed to correspond to changes in IOP. An advantage of the CLS is that 24 hour IOP measurements can be taken in ambulatory conditions and undisturbed sleep. Ten patients with TED had the CLS placed on one eye for 24 hours. Study patients kept an activity diary for half hourly information of their activity, such as sleep, meals, physical activity. Results showed adverse events associated with the CLS included mild blurred vision (50%), mild hyperaemia (100%) and superficial punctate keratitis (20%). All adverse events were transient and resolved after CLS removal. Overall, when evaluating the whole study group, this model showed a nocturnal / sleep acrophase, with the peak occurring at 06:30hrs. Specifically, 50% of patients had a significant nocturnal / sleep acrophase, 20% had a significant diurnal acrophase, and 30% had no significant acrophase. The authors conclude that the CLS is a safe and well tolerated device in patients with TED and patients with TED are most likely to have a morning acrophase.

Reference

Twenty-four hour intraocular pressure patterns in patients with thyroid eye disease.
Parekh AS, Mansouri K, Weinreb RN, et al.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2015;43:108-14.

CURRENT EYE RESEARCH

Air toxicity on retinal pigment epithelium
Reviewed by: Khadijah Basheer
Vol 22 No 2
 

This study investigated the potential toxic effects of air on primary human retinal pigment epithelial (RPE) cells in vitro. Clinically during pars plana vitrectomy air is used as either a temporary tamponade during air-fluid exchange or mixed with gas to provide an internal tamponade in the postoperative period lasting several days or weeks. The study showed that the RPE cells revealed large deformities after six hours of air exposure. They observed a more flattened, hypertrophic shape and a decrease in cell viability after 12 hours of exposure. Although during retinal surgery the RPE is not directly exposed to air, other animal studies have reported toxicity to the inner limiting membrane, nerve fibre layer and retinal ganglion cells. The obvious limitation to this study is that the model was not dynamic and not in vivo, however, it showed similar results to animal studies using cell culture models. Further studies are necessary in order to fully explore and apprehend the possible toxic effect of air on human retinal epithelium.

Reference

The toxic effect of air on primary human retinal pigment epithelium cells.
Kopsachilis N, Carifi G, Tsatsos M, et al.
CURRENT EYE RESEARCH
2015;40(6):555-60.

EXPERIMENTAL EYE RESEARCH

Transfected RPE cells inhibit AMD in rats
Reviewed by: Graham Wallace
Vol 22 No 2
 

Age-related macular degeneration (AMD) is a leading cause of blindness in the elderly. Wet AMD is characterised by choroidal neovascularisation, new vessels into the retina, leading to leakage and tissue damage. Many proangiogenic factors particularly vascular endothelial growth factor (VEGF) are fundamental to neovascularisation as shown by several drugs that block this pathway being used in AMD treatment. Fibulin-5 (Fbln5) is a matrix glycoprotein expressed in the retina and mutations in Fbln5 gene have been associated with increased risk of developing AMD. Fbln5 is an inhibitor of VEGF, a function that may explain the genetic data. In this paper retinal pigment epithelium cells were transfected with a lentivirus construct containing the FBln5 and GFP, such that the resultant cells overexpressed the protein and were green on fluorescence microscopy. CNV was induced by laser photocoagulation in rats and Fbln5-transfected RPE cells or RPE cells with the same construct, minus FBLn5, were injected into the subretinal space of the right and left eyes respectively. Transplanted RPE cells survived for at least four weeks, and eyes with Fbln5 overexpressing RPE cells showed a significantly smaller area of leakage and number of leakage spots compared to eyes transfected with control RPE cells. Growth and injection of RPE cells cultivated in vitro show promise for the treatment of AMD. This study demonstrates that manipulation of RPE cells prior to delivery to the eye can enhance the effect of such cells and provides a new area of research to define which genes will give the best results. This may depend on the potential to make stable contrasts to avoid continuous treatment, but the concept shown is important.

Reference

Subretinal transplantation of retinal pigment epithelium overexpressing fibulin-5 inhibits laser-induced choroidal neovascularisation in rats.
Li F, Zeng Y, Xu H, Yin ZQ.
EXPERIMENTAL EYE RESEARCH
2015;136:78-85.

INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE

Sustained elevation of extracellular ATP in chronic glaucoma
Reviewed by: Wai Siene Ng
Vol 22 No 2
 

Although adenosine 5′-triphosphate (ATP) release from retinal neurons and astrocytes has been demonstrated in short-term increases in intraocular pressure (IOP); such as in aqueous humor of humans with primary acute angle closure glaucoma, the response in chronic IOP elevation was not yet demonstrated and this group set out to investigate this in three different chronic glaucoma models (Tg-MyocY437H mice, rats with hypertonic saline injection into episcleral veins and monkeys with laser photocoagulation to the trabecular meshwork). They found increased levels of ATP in vitreal humor of all three models. Although contamination of intracellular ATP from cell rupture can occur, the group proceeded to further confirm this rise by measuring NTPDase1; an ectoenzyme which dephosphorylates ATP. This paper makes a good start at supporting the purinergic signalling pathway disturbance is sustained in glaucoma, suggesting a longer target window may be available for therapeutic rescue.

Reference

Rat, mouse and primate models of chronic glaucoma show sustained elevation of extracellular ATP and altered purinergic signalling in the posterior eye.
Lu W, Hu H, Sevigny J, et al.
INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE
2015;56:3075-83.

INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE

The impact of conjunctivochalasis on dry eye symptoms and signs
Reviewed by: Wai Siene Ng
Vol 22 No 2
 

The study aimed to draw a relationship between conjunctivochalasis and dry eye symptoms via a dry eye questionnaire (DEQ5), as well as signs such as tear osmolarity, tear break up time, corneal staining, Schirmer score, meibomian gland dropout, eye lid vascularity and meibum quality. The authors conclude that the presence of a nasally located conjuntivochalasis was associated with the most severe symptoms and signs. However, contrary to this, patients with no conjunctivochalasis had similar DEQ5 scores as patients with nasal conjunctivochalasis. Previous studies performed in China and Germany found increased dry eye symptoms in patients with nasal conjunctivochalasis. This study extends this by reporting a similarity in results for an American population. This paper is unique in that its patient cohort was a predominantly male population; an understudied population in dry eyes.

Reference

The impact of conjunctivochalasis on dry eye symptoms and signs.
Chhadva P, Alexander A, McClellan A, et al.
INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE
2015;56:2867-71.

JOURNAL OF REFRACTIVE SURGERY

Influence of FLEx and SMILE on corneal nerve density and ocular surface
Reviewed by: Mrinal Rana
Vol 22 No 2
 

This was a prospective study designed to compare the influence of femtosecond lenticule extraction (FLEx) and small incision lenticule extraction (SMILE) on the corneal nerve density and ocular surface for myopic correction. Thirty patients underwent bilateral lenticule extraction. One eye was randomly picked for FLEx and the other had SMILE. Inclusion criteria included unsatisfactory visual acuity even with spectacle or contact lens correction, myopic refractive error ranging between -1 to -9D, corneal thickness >400mic and residual stromal bed of 250microns. Surgical procedure for FLEx and SMILE involved use of VisuMax femtosecond laser system with 500KHz repetition rate. The incision pattern followed an automated sequence of posterior surface of lenticule, then anterior surface of lenticule and side cut flap. After completion of laser sequence for FLEx the flap was lifted, lenticule grasped and extracted. The flap was repositioned and interface flushed and for SMILE, the spatula was inserted through the side cut over and under the lenticule to free it from its adhesions and then grasped and pulled out. Sub-basal nerve density was measured using confocal microscope (HRT3 Rostock Cornea Module, Heidelberg Engineering GmbH) at one week, one and three months and one year postoperatively. Ocular surface parameters like Schirmer test, tear film break up time and corneal sensations were also performed pre and postoperatively at one and three months. The results were significantly favouring the SMILE correction with sub-basal nerve density postoperatively at 11,870±8200 microns/mm² compared to 5770±3490 microns/mm² with FLEx. The ocular surface parameters were found to be significantly reduced, when FLex was compared with SMILE. This supports further the reduction in the sub-basal nerve density. The limitations of the study were low number sample size and lack of impression cytology to look at conjunctival goblet cells and their effect on ocular surface parameters. These results do add further to evidence that prove that SMILE is better than FLEx when treating myopia in a minimally invasive fashion.

Reference

Influence of femtosecond lenticule extraction and small incision lenticule extraction on corneal nerve density and ocular surface: A 1 year prospective, confocal, microscopic study.
Ishii R, Shimizu K, Igarashi A, et al.
JOURNAL OF REFRACTIVE SURGERY
2015;31(1):10-5.

NEURO-OPHTHALMOLOGY

A case of progressive supranuclear palsy-like syndrome following aortic aneurysm repair
Reviewed by: Claire Howard
Vol 22 No 2
 

This original article illustrates the case of an 18-year-old woman who developed progressive supranuclear palsy-like syndrome following an uneventful aortic aneurysm repair. The patient was unaffected for the first 48 hours after surgery and then developed dysarthria, dysphagia (requiring a gastric tube), emotional lability and ophthalmoplegia. The authors have provided a video of the patient to illustrate how profound these deficits were. The patient underwent extensive contrasted fat suppressed cranial and orbital MRI, MRI tractography and functional MRI. Given the extensive degree of neurological impairment, the authors expected this advanced neuroimaging to be abnormal, however, it revealed no clear radiographic involvement, except for a tiny hypoechoic midbrain dot which is not considered sufficient to account for the patient’s deficits. This case attests to the unknown and unusual nature of this rare and devastating syndrome.

Reference

Functional magnetic resonance imaging (MRI) and MRI tractography in progressive supranuclear palsy-like syndrome.
Vaphiades MS, Visscher K, Rucker JC, et al.
NEURO-OPHTHALMOLOGY
2015;39(2):64-8.

NEURO-OPHTHALMOLOGY

A case series of acquired esotropia in cerebellar disease
Reviewed by: Claire Howard
Vol 22 No 2
 

Acquired esotropia in cerebellar disease is well described but under-recognised. The pathogenesis of cerebellar esotropia is controversial. It is suggested it may be a result of disruption to central vestibular pathways. This article reports a case series of seven adults with diplopia secondary to cerebellar dysfunction. The authors describe a deterioration of cerebellar esotropia over time. This has not previously been reported. All the patients were initially diagnosed with lateral rectus paresis, the diagnosis being revised after examination showed no slowing of abducting saccades and full abduction with gaze evoked nystagmus. The authors aim was to demonstrate that diplopia due to cerebellar esotropia can be the first manifestation of the underlying disorder and as such the condition may be misdiagnosed. This is something for clinicians to bear in mind when assessing patients with newly acquired symptoms.

Reference

Acquired esotropia in cerebellar disease: a case series illustrating misdiagnosis as isolated lateral rectus paresis and progression over time.
Wong SH, Patel L, Plant GT.
NEURO-OPHTHALMOLOGY
2015;39(2):59-63.

NEURO-OPHTHALMOLOGY

A case series of acute visual loss following excessive alcohol and / or drug use
Reviewed by: Claire Howard
Vol 22 No 2
 

This study presents three cases of so called Saturday night retinopathy, an acute visual loss following intravenous drug abuse and stupor, leading to continuous pressure on the orbit while asleep. All three cases presented with acute vision loss and had funduscopic evidence of ophthalmic or central retinal artery occlusion. Two of the cases also presented with ophthalmoplegia and proptosis. One of the cases had significantly increased intraocular pressure and corneal oedema. All three cases had poor visual outcomes with severe visual loss in the affected eye and no recovery. The authors detail the cases with photographs and imaging and discuss the possible causes for this finding. It is thought that prolonged periods of altered mental state inhibit spontaneous movement, which would normally alleviate the focal compression during normal sleep. Unfortunately no treatment has proven to be of any benefit.

Reference

Saturday night retinopathy with ophthalmoplegia: a case series.
Malihi M, Turbin RE, Frohman LP.
NEURO-OPHTHALMOLOGY
2015;39(2):77-82.

NEURO-OPHTHALMOLOGY

Neuro-ophthalmological symptoms in patients with cerebral venous sinus thrombosis
Reviewed by: Claire Howard
Vol 22 No 2
 

The authors of this article have evaluated the neuro-ophthalmological symptoms of 49 patients with cerebral venous sinus thrombosis. They have evaluated the onset of the disease as well as the symptoms reported. The authors present extensive clinical information for individual cases including clinical presentation, treatment and overall outcome. Patients present with signs of intracranial hypertension, with papilloedema being one of the most frequent findings. Papilloedema was revealed in 84.6% of patients with acute and subacute onset and in all patients in the chronic phase of onset. Patients with acute onset of cerebral venous sinus thrombosis were successfully treated with local endovascular thrombolysis. Patients with chronic onset, where visual disturbance was present, required lumboperitoneal shunting to prevent any further loss of vision. The article highlights the outcome of treatment for varying stages of onset, this should be considered when planning management for this patient group.

Reference

Neuro-ophthalmological features of cerebral venous sinus thrombosis.
Eliseeva N, Serova N, Yakovlev S, et al.
NEURO-OPHTHALMOLOGY
2015;39(2):69-76.

NEW ENGLAND JOURNAL OF MEDICINE

Persistence of Ebola virus in ocular fluid during convalescence
Reviewed by: Jonathan C P Roos
Vol 22 No 2
 

The most recent Ebola outbreak has infected over 26,300 patients, but also resulted in the highest number of survivors in history. Uveitis has been described during the convalescent period, but Varkey and colleagues report, for the first time, finding viable Ebola virus in the aqueous fluid of a 43-year-old male doctor nine weeks after clearance of viraemia. At this point a patient would ordinarily no longer be considered infectious. The patient had been treated with an experimental small RNA interfering agent, as well as convalescent plasma (blood product from an Ebola survivor) and supportive care for multi-organ failure including ventilation and haemodialysis. After a protracted ICU stay his blood and urine tested negative for virus and he was discharged home. Interestingly, as his semen continued to test positive for virus, he was advised to abstain from sex or to use condoms for at least three months. This is noteworthy as the gonads are an immune-privileged site alongside the eye, brain and articular cartilage. After discharge, the patient, who had no previous ocular history, began to complain of symptoms of uveitis and a foreign body sensation. Repeat examinations revealed stable bilateral chorioretinitis but a marked anterior chamber reaction and elevated IOP of 44mmHg then developed. Topical prednisolone drops resulted in a rapid deterioration and an aqueous tap revealed viable Ebola virus. Reassuringly, a conjunctival swab and tear film fluid were negative. The patient continued to deteriorate with marked scleritis and uveitis. The marked vitritis was treated with periocular triamcinolone, oral faviparivir and oral steroids. After six weeks the patient had recovered. The authors concluded that this panuveitis was due to the direct cytopathic effect associated with viral replication as this has previously been seen with Marburg virus. This case demonstrates that the eye can act as a reservoir of infection for Ebola which has significant implications for all clinicians. Ophthalmologists should take extra precaution during ocular examinations and procedures in patients suspected of having, or who have recovered from, Ebola virus.

Reference

Persistence of Ebola virus in ocular fluid during convalescence.
Varkey JB, Shantha JG, Crozier I, et al.
NEW ENGLAND JOURNAL OF MEDICINE
2015;372:2423-7.

OCULAR IMMUNOLOGY AND INFLAMMATION

Allografts in limbal stem cell deficiency
Reviewed by: Saruban Pasu
Vol 22 No 2
 

This prospective comparative study compared outcomes of live related limbal allograft (Lr-CLAL) versus cadaveric keratolimbal allograft (KLAL) in limbal stem cell deficiency secondary to ocular burns. Twenty patients were randomly allocated into each group. The Lr-CLAL group had a significant decrease in conjunctivalisation, improved tear break up time and increase in Schirmer’s values at six month follow-up. Three eyes had either persistence or increase in conjunctivalisation after three months in the Lr-CLAL group, compared to eight eyes in the KLAL group. There were no intraoperative complications. Significant visual improvement was seen in 8/10 patients in the Lr-CLAL group and 5/10 in the KLAL group. There was a statistically significant difference between the two groups at six months follow-up. Corneal clarity was better maintained in the Lr-CLAL group. This study suggests that live related allograft may provide better visual and anatomical outcomes than keratolimbal allograft for management of limbal stem cell failure secondary to chemical or thermal burns.

Reference

Live related versus cadaveric limbal allograft in limbal stem cell deficiency.
Titiyal J, Sharma N, Agarwal A, et al.
OCULAR IMMUNOLOGY AND INFLAMMATION
2015;23(3):232-9.

OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY

Botulinum toxin after orbicularis myectomy
Reviewed by: James Hsuan
Vol 22 No 2
 

This is a retrospective review of 27 patients with benign essential blepharospasm who had become resistant to treatment with botulinum toxin and had therefore undergone orbicularis myectomy of the upper lids. The study compares the dose and frequency of botulinum toxin treatment before and after the myectomy procedure. Three patients needed no further botulinum toxin injections, and the remaining patients required a significantly smaller dose to the upper lids to achieve the same effect compared with their pre-surgery regimens. Furthermore the frequency of injections was also significantly less, reducing from every 10.1 weeks to every 15.7 weeks on average. The authors assessed the cost implications based on Medicare data and found that patients undergoing surgery cost over $11,000 less to treat over a 10 year period than those who persisted with injections alone. This is an interesting paper supporting the use of myectomy for blepharospasm patients who become resistant to botulinum toxin. The vast majority of patients still require on-going injections, but less frequently and with a smaller dose. It would be interesting to know if the same was true in non-resistant patients. The authors do not mention any side-effects from the surgery, but do admit that a weakness of their study was that a formal assessment of patient satisfaction was not performed. Other confounding factors are the simultaneous ptosis surgery and the subjective criteria to determine the efficacy of the botulinum toxin treatment. Despite these weaknesses, the study provides useful evidence for the efficacy and cost-effectiveness of myectomy surgery.

Reference

Effect of upper eyelid myectomy on subsequent chemodenervation in the management of benign essential blepharospasm.
Kent TL, Petris CK, Holds JB.
OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY
2015;31:222-6.

OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY

Conjunctival melanoma involving the lacrimal drainage system
Reviewed by: James Hsuan
Vol 22 No 2
 

A total of 52 patients were diagnosed with conjunctival melanoma over a period of 17 years, 17 of whom required orbital exenteration. Five of these were found to have melanoma involving the lacrimal drainage apparatus (LDA). One was evident clinically prior to exenteration, one was found to have sac involvement during exenteration, and another was discovered only on histological examination post-exenteration. The two remaining cases developed recurrent disease in the lacrimal sac two to three years post-exenteration. The authors recommend sac and proximal duct excision as a routine during exenteration for conjunctival melanoma. This is a very interesting paper with a high rate of LDA involvement compared to previous reports. The authors speculate on the mechanism of spread to the lacrimal sac, but it is noteworthy that all patients had undergone a previous biopsy of the lesion, and many had multiple previous resections. The risk of seeding of melanoma from biopsy or incomplete excision is well known, and this must be considered as a likely cause for the LDA spread. It is also of interest that the canaliculi were involved in only one patient. This reinforces the seeding hypothesis, and the message that histologically normal canaliculi should not reassure the surgeon that the sac or duct are definitely free of disease.

Reference

Malignant melanoma of the lacrimal drainage apparatus complicating conjunctival melanoma.
Satchi K, McKelvie P, McNab AA.
OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY
2015;31:207-10.

OPHTHALMIC RESEARCH

Cytotoxic effect of voriconazole on human corneal epithelial cells
Reviewed by: Bheemanagouda Patil
Vol 22 No 2
 

Voriconazole is a second-generation synthetic derivative of fluconazole with broadened antifungal spectrum. It is becoming the drug of choice for fungal keratitis. Voriconazole eye drops are not available commercially, thus have to be prepared by diluting the intravenous formulation containing 10mg of voriconazole and 160mg/ml sulfobutylether-β-cyclodestrin sodium (SBECD). SBECD is added to voriconazole to increase solubility, aqueous stability and bioavailability of the drug. The aim of this study was to assess the cytotoxic properties of various concentrations of voriconazole and SBECD on cultured primary human corneal epithelial cells (0.001–2mg/ml). No corneal epithelial cytotoxicity was observed below the concentration of 0.08 and 0.025mg/ml after 24-hour exposure to SBECD and voriconazole respectively. The results of this study reveal the dose-dependent cytotoxic effect of SBECD and voriconazole and thus they recommend that voriconazole eye drops should be used cautiously in the treatment of fungal keratitis.

Reference

Cytotoxic effect of voriconazole on human corneal epithelial cells.
Sobolewska B, Guerel G, Hofmann J, et al.
OPHTHALMIC RESEARCH
2015:54;41-7.

OPHTHALMIC RESEARCH

Topical atorvastatin for dry eye and blepharitis
Reviewed by: Bheemanagouda Patil
Vol 22 No 2
 

Dry eye is a very common problem with 20% of the population affected and is frequently associated with blepharitis (DEB), which has an over prevalence of about 40%. The aim of this study was to evaluate a topical atorvastatin formulation in a pilot study of DEB to assess the feasibility of a larger comparative trial. Ten DEB patients were enrolled in this prospective study. All patients were treated with topical atorvastatin (50µM) eight times daily for four weeks. They were allowed to continue their existing dry eye treatment. The primary outcome measure was corneal fluorescein staining. Secondary outcome measures were tear break up time (BUT), Schirmer testing, blepharitis score and bulbar conjunctival injection. An improvement in corneal fluorescein staining in the treated eye by >1 point from baseline to four weeks was seen in nine of 10 patients (p<0.01). Topical atorvastatin also significantly improved the tear break up time (p<0.01), blepharitis score (p<0.05) and bulbar conjunctival injection (p<0.05). There were no side-effects. They conclude that topical atorvastatin could be a potential therapy for DEB patients; however, larger comparative trials are needed to establish safety and efficacy.

Reference

Efficacy and safety of topical atorvastatin for the treatment of dry eye associated with blepharitis: a pilot study.
Ooi KG, Wakefield D, Billson FA, Watson SL.
OPHTHALMIC RESEARCH
2015;54:26-33.

OPHTHALMOLOGICA

Stereotactic radiotherapy for polypoidal choroidal vasculopathy
Reviewed by: Sofia Rokerya
Vol 22 No 2
 

Polypoidal choroidal vasculopathy (PCV) is a variant of neovascular AMD. It is a disease of choroidal vasculature characterised by abnormal branching vascular network with aneurysmal dilatations (polyps). Features of PCV include pigment epithelial detachments (PED), subretinal fluid (SRF) accumulation and haemorrhage. Indocyaninegreen angiography (ICGA) is essential for the identification of polyps. Anti-VEGFs are partially effective, as polyps persist and chronic exudation can lead to continued tissue destruction and permanent vision loss. PDT with verteporfin has been proven to stabilise visual acuity. Subretinal haemorrhage after PDT can occur and the efficacy of this treatment decreases over time. Radiotherapy has been proposed for the management of nAMD as it can induce regression of new vessels and inhibit both inflammation and fibrosis. However, this treatment can be accompanied by difficulties in accurate targeting and the inability to avoid collateral damage to surrounding tissues by dispersed energy. In this study the authors evaluate the results of a single centre, pilot study for 12 eyes of 12 patients enrolled with active PCV located in an area 4mm around the fovea, who were treated with 0.5mg ranibizumab and 16 GY X-ray SRT in a single session followed by prn intravitreal ranibizumab injections. The IRay System is an SRT device that generates x-rays from a low-voltage source. Narrow collimation of the beam, as well as immobilisation and real-time tracking of the eye motion, allow precise radiation delivery onto the macular target. The mean age of the patients included in this study (10 males and two females) was 70.01 ±6.04 years, and the mean axial length of the studied eyes was 23.05 ±0.9 mm. Nine of the 12 eyes were treatment naive; the other three eyes had previously received intravitreal bevacizumab injections. Eyes were evaluated for angiographic regression of polyps, improvement in visual acuity and central foveal thickness (CFT), at three, six and 12 months. At month three, choroidal polyps were no longer visible on ICGA in 10 of the 12 eyes. These 10 eyes (83.3%) maintained complete regression of polyps at month 12. At month 12, the mean BCVA improved from 65.08 ±11.4 to 72.7 ±14.75 ETDRS letters, 10 eyes had BCVA improvement, two gained >15 letters, and five eyes gained ≥10 letters. Two eyes had BCVA decreases (one and two letters, respectively). The mean CFT significantly decreased from 372.3 ±79.6μm at baseline to 215.9 ±57.9μm at month 12 (p value of the t test <0.01). The total mean number of intravitreal ranibizumab injections was 2.9 ±1.3 (range 1–5) and 3.9 ±2.5 (range 1–8) at months six and 12, respectively. No ocular or systemic adverse events or serious adverse events were observed during the study period. There were no signs of typical radiation-induced microangiopathy, such as microaneurysms, cotton wool spots and haemorrhage, on ophthalmoscopy or in the colour photographs. A limitation of the x-ray SRT device used in this study is the fixed nature of its irradiated spot, which is 4mm in diameter and centred on the macula, with no option to adjust its size or position. PCV may present as lesions variably located at the posterior pole and often at the peripapillary area, along the vascular arcades or in the temporal part of the retina – areas that are not treated by the SRT technology evaluated in this trial. In conclusion, the data from the pilot low-voltage x-ray SRT combined with intravitreal ranibizumab for the treatment of PCV showed that this therapy is safe and potentially effective, as indicated by the observed polyp closure, decreases in CFT and improvements in visual acuity of low-voltage x-ray SRT in the treatment of PCV.

Reference

Stereotactic radiotherapy for polypoidal choroidal vasculopathy.
Introini U, Casalino G, Triolo G, et al.
OPHTHALMOLOGICA
2015;233:82-8.

OPHTHALMOLOGY

Outcomes of ‘treat and extend’ for neovascular AMD
Reviewed by: Brian Ang
Vol 22 No 2
 

The authors report on 24-month outcomes of anti-vascular endothelial growth factor (anti-VEGF) therapy using a ‘treat and extend’ regime for treatment-naïve neovascular age-related macular degeneration (nAMD). Data for this study was collected from the Fight Retinal Blindness observational registry based in Australia and New Zealand. The treat and extend protocol involved initial treatment once every four weeks until the nAMD was no longer active. This was followed by extension of treatment interval by one to two weeks, provided the visual acuity was stable and there were no clinical or OCT signs of activity. Should there be recurrence of nAMD activity, the treatment interval was shortened again. In total, 1198 eyes of 1011 patients were included in the study. Ranibizumab monotherapy was received by 588 eyes (49%) while bevacizumab monotherapy was received by 25 eyes (2%). Five hundred and eighty-five eyes (49%) received a combination of bevaczumab, ranibizumab and aflibercept. Over the two year study period, the mean number of injections was 13 per eye (7.5 in the first year, and 5.5 in the second year). The mean number of visits was 14.8 (7.9 in the first year, and 6.7 in the second year). The endophthalmitis rate was 0.013% (one per 7272 injections). Visual acuity improved by a mean of 5.3 letters (from 56.5 at baseline to 61.8 at 24 months). The proportion of eyes achieving a vision of 6/12 increased from 27% at baseline to 45% at 24 months, while those with vision worse than 6/60 remained unchanged (13% at baseline; 11% at 24 months). Although there were quite a number of eyes that were lost to follow-up, this shows that ‘treat and extend’ for nAMD can achieve good visual outcomes in routine clinical practice and at the same time reduce the need for monthly clinic visits and injections.

Reference

Two-year outcomes of “treat and extend” intravitreal therapy for neovascular age-related macular degeneration.
Arnold JJ, Campain A, Barthelmes D, et al.
OPHTHALMOLOGY
2015;122:1212-9.

OPHTHALMOLOGY

Postural control in glaucoma patients with virtual reality
Reviewed by: Brian Ang
Vol 22 No 2
 

The authors report on a cross-sectional study evaluating postural control and history of falls in glaucoma patients. History of falls was obtained using the Falls Screening and Referral Algorithm. Postural stability was assessed using a force platform under four conditions: static condition, dark field without visual stimulation, rotational stimulation and translational stimulation. Visual stimulation was achieved with the Oculus Rift, a head-mounted stereoscopic goggles system that projects an immersive virtual environment for the wearer. Torque moments that are generated on the force platform due to a shift in the patient’s centre of gravity are measured as standard deviations of the torque moments (STD) in Newton metres (Nm). Forty-two glaucoma patients and 38 healthy controls participated in the study. As expected, the diagnosis of glaucoma was significantly associated with a history of falling. Significantly greater STD was found in glaucoma patients for static conditions (no stimulus) as well as translational and rotational stimuli. In glaucoma patients, falls were associated with only dynamic translational stimulation once multivariate analysis was performed taking into account age, body mass index, visual field defect severity and visual acuity. In healthy subjects, none of the postural metrics were associated with falls. Despite the limitations of the study (small sample size, musculoskeletal and vestibular tests not performed, falls not evaluated prospectively), this is an interesting paper describing a novel way of evaluating postural control in glaucoma patients.

Reference

Evaluation of postural control in patients with glaucoma using a virtual reality environment.
Diniz-Filho A, Boer ER, Carolina PBG, et al.
OPHTHALMOLOGY
2015;122:1131-8.

STRABISMUS

Binocular summation with low contrast
Reviewed by: Fiona Rowe
Vol 22 No 2
 

The magnitude of binocular summation was investigated in normal control subjects using four different letter charts of varying type with fixed and variable contrast levels and spatial frequency to determine which tests most readily reveal binocular summation in normal subjects. Tests included the low contrast Early Treatment Diabetic Retinopathy Study (ETDRS) and Pelli Robson contrast sensitivity charts plus high contrast ETDRS chart at 2.5 and 1.25% levels. One hundred and twenty-nine subjects were tested: 61% female, 39% male. A significant difference in binocular summation was found in different age groups for 2.5% and 1.25% Sloan low contrast acuity charts and the Pelli Robson chart, but not for high contrast ETDRS visual acuity. Generally scores increased over the first three decades of life and reduced from the fifth decade. Linear regression showed significant associations between increased intraocular differences and reduced binocular summation and increased age and reduced binocular summation. Low contrast acuity charts may be useful clinical measures of binocular summation.

Reference

Normative reference ranges for binocular summation as a function of age for low contrast letter charts.
Pineles SL, Velez FG, Yu F, et al.
STRABISMUS
2014;22:167-75.

STRABISMUS

BT for intermittent exotropia
Reviewed by: Fiona Rowe
Vol 22 No 2
 

This study aimed to evaluate the effect of botulinum toxin (BT) on the amount of deviation and fusional control state of intermittent exotropia. Twenty-one patients (five male and 16 female) aged five to 18 years with progression of exotropia were recruited. Each had reduced fusional control and an increased Newcastle control score (≥3). BT of 10 units Dysport was given to the lateral rectus muscles. A minimum follow-up of six months was allowed. The Newcastle control score increased significantly over follow-up. Stereoacuity improved from 224.6 ±278.9” pre-treatment to 100 ±100.3” post treatment. The near angle of deviation reduced from 26.4 ±10.1 to 1.8 ±10.3PD and the distance angle of deviation reduced from 30.9 ±7.1 to 11.8 ±14.4PD. Binocular alignment within 10PD was achieved by 38.1% at distance fixation. Mild ptosis was documented in nine patients (42.8%). The authors propose this to be a promising treatment.

Reference

Efficacy of botulinum toxin in the treatment of intermittent exotropia.
Etezad Razavi M, Sharifi M, Armanfar F.
STRABISMUS
2014;22:176-81.

STRABISMUS

Dyslexic reading improved by vergence training
Reviewed by: Fiona Rowe
Vol 22 No 2
 

The aim of this study was to evaluate if reading performance could be improved by a period of compensatory vergence training in dyslexic children with otherwise normal binocular vision. The study included 13 children with dyslexia – mean age of 13.08 ±0.49 years at time of treatment. Twelve control dyslexics were also recruited with a mean age of 13.08 ±0.51 years. Over a five week period training was provided averaging 11.75 times ±2.53SD. The mean number of words read pre-treatment was 87.83 ±16.80 and after treatment was 95.58 ±18.08 which was significant, p=0.0066. The mean number of words read by control subjects at baseline was 85 ±19.68 and at the second visit, 89.37 ±19.71 which showed no significant difference. An increase in positive fusional reserves at near fixation was recorded for the treatment group. The authors conclude there is a beneficial improvement in reading ability following vergence training for dyslexics.

Reference

Can vergence training improve reading in dyslexics?
Ramsay MW, Davidson C, Ljungblad M, et al.
STRABISMUS
2014;22:147-51.

STRABISMUS

Iran prevalence of amblyopia
Reviewed by: Fiona Rowe
Vol 22 No 2
 

The authors aimed to determine the prevalence of amblyopia, its relation with refractive errors and its determinants. The target population was all children aged seven years in Iran. There were 3675 of 4157 children who participated (88.4%) with final analysis on 3547 children with full data. Sixty-three had amblyopia (1.88%: 1.91% male and 1.85% female). Of that 60.3% had unilateral amblyopia; 73.9% had corrected visual acuity better than 20/40 and 5.7% with visual acuity <20.80; 51.3% had strabismic amblyopia, 27% anisometropic, 9.5% isotropic, 11.1% strabismic plus anisometropic, and 1% with stimulus deprivation amblyopia due to cataract. Amblyopic eyes were more hyperopic with a higher mean cylinder error. The authors conclude that attention should be paid to hyperopia and astigmatic refractive errors and to treatment of strabismus cases.

Reference

The prevalence of amblyopia in 7-year-old school children in Iran.
Hashemi H, Yekta A, Jafarzadehpur E, et al.
STRABISMUS
2014;22:152-7.

STRABISMUS

Medial rectus recession in Grave’s orbitopathy
Reviewed by: Fiona Rowe
 

The purpose of this retrospective study was to analyse the surgical effect / success rate of recession of the medial rectus in 90 patients with horizontal diplopia. Mean age was 52.5 ±9.4 years. Of that 24% had unilateral medial rectus recession and 76% had bilateral recessions. Mean recession was 3.3 (2-5mm) for unilateral recession and 4.5 (2.7-7mm) for bilateral. Preoperative angle of deviation was not influenced by muscle volume or decompression approach. Dose response was 1.0 (-0.6 to 3.8) degrees/mm for unilateral recession and 1.4 (0.2 to 3) degrees/mm for bilateral. Overall approximately 80% required one operation only to resolve horizontal diplopia.

Reference

Unilateral and bilateral medial rectus recession in Grave’s orbitopathy patients.
Jellema HM, Saeed P, Braaksma-Besselink Y, et al.
STRABISMUS
2014;22:182-7.

AMERICAN JOURNAL OF OPHTHALMOLOGY

Does paediatric uveitis reactivate after treatment with anti-TNF-a drugs?
Reviewed by: Efrosini Papagiannuli
Vol 22 No 1
 

As a potentially blinding disease that can affect 7-27/100000 children, uveitis remains a rare condition, where little evidence based data is available to guide management decisions. Most paediatric uveitis cases are chronic, anterior and non-infectious and may be associated with juvenile idiopathic arthritis (JIA) or remain undifferentiated. Anti-TNF-a treatment is the treatment of choice in patients with uveitis resistant to standard therapy with steroids and traditional immunomodulators (commonly Methotrexate). The aim is a flare free period (quiescence) of 18-24 months, before considering to discontinue any systemic treatment. The aim of this paper was to address the risk of reactivation whilst patients were still on anti-TNF-a (primary outcome), after they stopped it (secondary outcome) and also potential risk factors for reactivation. This retrospective cohort study builds upon a previously published paper by the same authors, demonstrating that 75% of children with non-infectious uveitis achieved quiescence within 12 months with anti-TNF-a (Infliximab or Adalimumab) and that JIA uveitis was most likely to respond to treatment. (J Rheumatol 2013;40:1394-1403). It included patients whose management started between 01/2000 and 07/2012 and casenotes were reviewed, documenting whether there was non-infectious non-traumatic uveitis and whether they had received anti-TNF-a treatment. Quiescence was defined as having ‘slightly active’ (<0.5 cells) or inactive uveitis whilst on <2 drops/day of topical steroids and no oral steroids, sustained for >2 visits over a 28 day period. Infliximab and Adalimumab were the only anti-TNF-a drugs used and any concomitant treatment with steroids, Methotrexate and Mycophenolate Mofetil was documented. Among 50 children who achieved quiescence whilst on anti-TNF-a, 39 were considered at risk for reactivation whilst on anti-TNF-a (primary outcome) and 19 after discontinuation of treatment (secondary outcome). Of that 60% were female, nearly half had JIA and most were treated with Infliximab. The overall proportion relapsing within one year was 27.8% [95% CI]. The risk was higher in children who had discontinued Infliximab at 63.8% versus 21.6% in children still on treatment. In the group that discontinued anti-TNF-a, the risk of reactivation was higher if treated with Adalimumab, rather than Infliximab (HR 13.4, p=0.01). Reactivation was also higher in children that were older at the time of diagnosis of uveitis (HR 1.3, p=0.09). The duration of disease suppression on treatment (quiescence for >1.5 years) had no significant effect on the risk of reactivation. The authors conclude that whilst most children on anti-TNF-a remain quiescent, the majority will reactivate once off treatment. It also seemed that Infliximab was more often followed by remission, but that there was no benefit of prolonged drug induced disease suppression on the reactivation risk. The authors are aware of their study limitations, such as its retrospective nature, the variability in follow-ups and the fact that largely non-uveitis specialists were assessing disease activity. They also point out that some quiescent children may have been lost to follow-up and that there are limitations to the study’s generalisability as the cohort largely consisted of female Caucasians. They recommend further studies to assess whether short versus longer periods of suppression maintenance increase the risk of reactivation after drug cessation, to evaluate the potential advantages of Infliximab versus Adalimumab and to identify possible biomarkers that predict the likelihood of remission after treatment is discontinued.

Reference

Uveitis reactivation in children treated with tumor necrosis factor-a inhibitors.
Leman MA, Lewen MD, Kempen JH, Mills MD.
AMERICAN JOURNAL OF OPHTHALMOLOGY
Epub ahead of print.

AMERICAN JOURNAL OF OPHTHALMOLOGY

Endophthalmitis after intravitreal injections in France
Reviewed by: Efrosini Papagiannuli
Vol 22 No 1
 

In this nationwide, retrospective, multicentre case series, the authors looked at the incidence and characteristics of endophthalmitis after intravitreal injections of anti-VEGFs and steroids, given for a variety of posterior segment conditions (macular oedema secondary to diabetes or retinal vein occlusion, neovascular macular degeneration, degenerative myopia and miscellaneous cases). They wished to describe the clinical and bacteriological features, management and outcome (visual acuity) of these eyes. A total of 316,576 intravitreal injections from 25 centres were identified that underwent injections from January 2008 to June 2013. The intravitreal drugs used consisted of ranibizumab, bevacizumab, triamcinolone acetonide and dexamethasone implant. Case note review detected 65 cases of presumed endophthalmitis (0.021% incidence), with a median time to presentation of four days post-injection. Presumed endophthalmitis was defined as any acute intraocular inflammation presenting within four weeks of intravitreal injection and requiring intravitreal antibiotics (vancomycin with ceftazidime). The commonest symptom was loss of vision and an offending germ was detected in nearly 45%. The most frequent pathogen was coagulase negative Staphylococcus (78.3%).There was a significant association (p=0.001) with an increased incidence of endophthalmitis if a disposable conjunctival mould assist device or prophylaxis with antibiotic / antiseptic were used. Sixty-five percent of patients post episode had worse visual acuity at three months follow-up and one patient developed phthisis. In 61.7% of patients intravitreal injections were restarted after resolution of the endophthalmitis at a median time of 113 days. The authors conclude that the incidence of endophthalmitis after intravitreals is low, but associated with a poor visual prognosis. The strength of this study lies in its large sample size, but they acknowledge the various limitations, primarily its retrospective nature, the possibility of missing data or underreported endophthalmitis cases, the heterogenicity of the management in different French centres (relating to the use of corticosteroids and initial vitrectomy) and the fact that systemic antibiotics were part of the management, which is current practice in France but not supported in the literature. Furthermore they point out that because of variability in the level of asepsis and antisepsis from country to country (use of drapes, face masks, surgical hat, sterile gloves and gowns), any generalisability of their results to other countries ought to be very careful. They recommend further studies to define specific guidelines for endophthalmitis management.

Reference

Endophthalmitis after intravitreal injections: incidence, management and visual outcome.
Dossarps D, Bron AM, Koehrer P, et al.
AMERICAN JOURNAL OF OPHTHALMOLOGY
Epub ahead of print.

BRITISH JOURNAL OF OPHTHALMOLOGY

Efficacy and safety of intravitreal aflibercept injection in wet age-related macular degeneration
Reviewed by: Jonathan Chan
Vol 22 No 1
 

This is a sub-group study of double masked review of patients randomised to different dosages and treatment frequency compared between aflibercept and ranibizumab treatment. This is to evaluate the efficacy and safety of intravitreal aflibercept (IVT-AFL) in Japanese patients with wet age-related macular degeneration (AMD) from the VIEW 2 trial. Patients were randomised to: 0.5mg IVT-AFL every four weeks; 2mg IVT-AFL every four weeks; 2mg IVT-AFL every four weeks after three monthly injections; or 0.5mg ranibizumab every four weeks. The main efficacy outcomes included vision maintenance and best corrected visual acuity (BCVA) at week 52. The VIEW 2 trial was a prospective, double-masked, multinational, active-controlled, randomised, clinical trial. Eligible patients had sub-foveal choroidal neovascularisation (CNV) or juxta foveal CNV with subfoveal leakage demonstrated on fluorescein angiogram (FA) with appropriate lesion characteristics. Since polypoidal choroidal vasculopathy (PCV) is considered to be part of the AMD spectrum, patients with PCV lesions were not excluded. All Japanese patients in the IVT-AFL groups (n=70) at week 52 maintained vision, compared with 96% of Japanese patients (n=23/24) treated with ranibizumab. Japanese patients in all treatment groups show improvement in BCVA after treatment. Those treated at four weekly intervals with ranibizumab, compared with aflibercept treated at four weekly intervals and also eight weekly intervals, experienced similar gains in BCVA from baseline. The 0.5mg group had higher gains due to an unexpected drop in BCVA between screening and baseline. The central retinal thickness and mean area of choroidal neovascularisation decreased in all treatment groups with similar magnitude. The ocular treatment – adverse events were similar across the treatment groups. The authors concluded that IVT-AFL was effective and well tolerated in Japanese patients. The outcomes of this sub-group population were consistent with those in the overall VIEW 2 trial study of other population subjects.

Reference

Efficacy and safety of intravitreal aflibercept injection in wet age-related macular degeneration: outcomes in the Japanese subgroup of the VIEW 2 study.
Ogura Y, Terasaki H, Gomi F, et al.
BRITISH JOURNAL OF OPHTHALMOLOGY
2015;99:92-7.

BRITISH JOURNAL OF OPHTHALMOLOGY

Silicone band loop myopexy in the treatment of myopic strabismus fixus
Reviewed by: Jonathan Chan
Vol 22 No 1
 

This is a retrospective case series of chart review of patients who had silicone band loop myopexy between January 2008 to December 2012 for myopic strabismus fixus (MSF) at a tertiary eye centre in India. A minimum period of two months follow-up after surgery was required for inclusion, and patients who had previous incomplete details or preoperative alignment were excluded. The main outcome measures include alignment postoperatively, improvement in extraocular motility postoperatively, and intraoperative and posterior complications. The surgical procedure was performed under general anaesthetic and intraoperative forced duction test was performed in order to assess the tightness of each of the rectus muscles. A fornix base conjunctival incision was placed in the superotemporal quadrant approximately 10 to 12mm from the limbus. The lateral rectus and the superior rectus muscles were hooked and isolated and both were examined intraoperatively. A scleral tunnel of 3 to 4mm in length was constructed 14 to 16mm from the limbus in between the bellies of the superior rectus and lateral rectus using a hockey J stick buckle blade. A type 240 silicone band was then passed under the lateral rectus and through the scleral tunnel and the superior rectus. The two ends were then passed through a Watzke sleeve and tightened to bring the bellies of the superior rectus and lateral rectus together by pulling the two ends in opposite direction. The conjunctiva was closed with interrupted sutures using an 8-0 non-absorbable monofilament nylon suture. Forced duction test was repeated to look for the tightness and a medial rectus recession was performed if the medial rectus tightness was found to be significant. A total of 26 eyes of 15 patients had surgery at the mean age of 27.8±16.4 years (range 7-72 years). A mean follow-up was 7.9±8.4 months (range 2-28 months, and median of four months). Eleven patients had bilateral loop myopexy where four patients underwent unilateral loop myopexy. Sixteen eyes underwent additional medial rectus recession between a range of 5-7.5 mm. At the last follow-up, the mean abduction limitation improved to -1.5±1.3 from -2.9±1.2, P=0.0; mean elevation limitation improved to -1.2±0.9 from -2.8±1.1, P=0.0; mean esotropia improved to 16.9±17.4 PD from 79.3±32.3PD, P=0.0; success was defined as deviation less than 20 PD, was achieved in 73%. Mean hypotropia at presentation was 8.9±10.1 PD, which improved to 0.6±1.3 PD, P=0.007. Foreign body sensation was reported by two patients (three eyes) and a silicone band removal was performed in two eyes of one patient five months postoperatively. The patient maintained alignment 24 months postoperatively. The authors concluded that a modified fixated silicone band loop myopexy with or without medial rectus recession is a safe and effective procedure in the management of MSF and improves alignment significantly. Further studies particularly those comparing suture silicone band loop myopexy looking at the anterior ciliary circulation and muscle related complications are required.

Reference

Silicone band loop myopexy in the treatment of myopic strabismus fixus: surgical outcome of a novel modification.
Shenoy BH, Sachdeva V, Kekunnaya R.
BRITISH JOURNAL OF OPHTHALMOLOGY
2015;99:36-40.

CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY

Management of diffuse OSSN with topical chemotherapy
Reviewed by: Anjali Gupta
Vol 22 No 1
 

Ocular surface squamous neoplasia (OSSN) can be localised to the conjunctiva or, less commonly, diffusely spread over the conjunctiva and cornea. Localised OSSN can be treated by surgical removal with adjuvant cryotherapy and chemotherapy with low rates of recurrence. Diffuse OSSN is more difficult to treat without morbidity due to necessary reconstruction of the ocular surface after excision. Primary topical chemotherapy provides an alternative that avoids the potential complications of wide excision. This retrospective case series studied eyes with diffuse OSSN that were treated with topical 5FU 1% or topical MMC 0.04% as a primary therapy. Diffuse OSSN was defined as a lesion extending over five or more limbal clock hours or having extensive central or paracentral corneal spread. Thirty-two eyes were managed as treatment naive diffuse OSSN. Twenty-nine cases received MMC 0.04%, including one case that was partially surgically debulked prior to therapy. Seven out of the 28 cases (25%) displayed recurrence or persistence of OSSN. 5FU 1% was used in three cases of treatment naive OSSN and recurrence or persistence of disease was observed in all cases. Thirteen cases had previously undergone a single unsuccessful treatment course for diffuse OSSN, administration of a second treatment course was successful in six (46%) of these patients. A strategy of switching treatment protocol from 5FU 1% to MMC 0.04% following treatment failure was attempted in seven patients, and tumour clearance was achieved in four. Conversely, retreatment with 5FU 1% following treatment failure with MMC 0.04% was attempted in five cases, and tumour clearance was successful in four. In four patients, following treatment with MMC 0.04% or 5FU 1%, tumour clearance was ultimately achieved with excision and cryotherapy of a localised area of recurrence. No serious long-term complications were noted with MMC 0.04%, one case treated with 5FU 1% experienced a focal stromal melt. The authors conclude that diffuse OSSN often requires multiple treatment efforts when compared with localised disease. Switching chemotherapeutic regimens following a treatment failure may be useful.

Reference

Management of diffuse ocular surface squamous neoplasia: efficacy and complications of topical chemotherapy.
Rudkin AK, Dempster L, Muecke JS.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2015;43:20-5.

CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY

Micropulse vs. continuous wave trans scleral diode cyclophotocoagulation in refractory glaucoma
Reviewed by: Anjali Gupta
Vol 22 No 1
 

Continuous wave cyclophotocoagulation (CWCPC) delivers continuous high intensity energy to the ciliary body in an attempt to reduce aqueous secretion and hence lower IOP. It is often used as a treatment of last resort due to the potential side-effects of hypotony, visual deterioration and phthisis bulbi. Micro pulse cyclophotocoagulation (MPCPC) administers a series of repetitive, short pulses of laser energy separated by rest periods. A preliminary study has described MPCPC to achieve IOP reduction that is sustained over 12-18 months without significant ocular comorbidity. This randomised comparative exploratory study compared the efficacy and safety of MPCPC and CWCPC in refractory glaucoma. Forty-eight patients with refractory glaucoma (IOP>21 unresponsive to maximal tolerated medical therapy with or without previous surgical intervention) and a best corrected visual acuity (BCVA) of 6/60 or worse were randomised to either CWCPC or MPCPC. Twenty-four patients were allocated to each group. The primary outcome of success was IOP between six and 21mmHg and at least 30% reduction in IOP with or without medical therapy. After 12 months, 75% of patients in the MPCPC vs. 29% in the CWCPC achieved the primary outcome. However, there was no significant difference between the two treatment modalities achieving primary outcome success at 18 months. More complications were seen in the CWCPC group, including prolonged anterior chamber (AC) inflammation and phthisis bulbi. The authors conclude that MPCPC provides a more consistent and predictable effect in lowering IOP with minimal complications.

Reference

Micropulse versus continuous wave trans scleral diode cyclophotocoagulation in refractory glaucoma: a randomised exploratory study.
Aquino MCD, Barton K, Tan AMWT, et al.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2015;43:40-6.

CORNEA

Oral omega-3 fatty acid treatment for dry eye in contact lens wearers
Reviewed by: Sharmina Khan
Vol 22 No 1
 

This study evaluates the effect of dietary omega-3 fatty acid supplementation of dry eye symptoms, tear film tests, and conjunctival impression cytology in patients with contact lens wear-associated dry eye. In this randomised double-blind, multi-centred trial, contact lens wearers (n= 496) were randomised to receive either omega-3 fatty acids or placebo capsules (corn oil) twice daily for six months. At each visit a questionnaire of dry eye symptoms were completed, tear film break up time (TBUT), Schirmer’s test, conjunctival impression cytology. Outcomes measures were improvement in symptoms and lens wear comfort. Changes in TBUT, Schirmer’s test and Nelson grade (conjunctival impression cytology scores) at six months were secondary outcomes. Exclusion criteria were: current ocular infection, history of laser refractive surgery, allergic conjunctivitis, herpetic eye disease, diabetes, liver disease, pregnancy, lactation, HIV, hepatitis, those on systemic tetracyclines, systemic corticosteroids, topical medications other than artificial tears. Computer use was not allowed for the duration of the study. The mean contact lens wear time was 3.1 +/- (0.91) years in the omega-3 fatty acid supplements group and 3.3 +/- 2 (1.6) years. Noncompliance and gastric irritation resulted in 14 patients dropping out of the trial. The mean age was comparable in both groups. Patients were instructed not to use artificial tears two hours before testing. The mean improvement in symptom score was significantly improved from baseline for the cohort receiving omega-3 supplements versus the placebo group, this was associated with a significant increase in TBUT. However, improvement in Schirmer’s test was small. Omega-3 is an essential fatty acid that can’t be synthesised by the body but has to be ingested. It has anti-inflammatory properties. Omega-6 fatty acids are pro-inflammatory. The ratio of omega-3 and omega-6 determines the overall inflammatory status of the body.

Reference

Oral omega-3 Fatty acid treatment for dry eye in contact lens wearers.
Bhargava R, Kumar P.
CORNEA
2015;34:413-20.

CORNEA

Tear film thickness after treatment with artificial tears in patients with moderate dry eye disease
Reviewed by: Sharmina Khan
Vol 22 No 1
 

In recent years artificial tear drops addressing tear film osmolarity have come onto the market. Increased tear evaporation and reduced tear volume results in tear hyperosmolarity. This triggers an inflammatory process leading to apoptosis of goblet and epithelial cells. Trehalose, a naturally occurring disaccharide has been marketed. This study uses anterior segment ultra-high resolution optical coherence tomography (OCT) to assess pre corneal tear film thickness (TFT) following use of artificial tear drops; (i) Thelaoz Duo – Trehalose 30mg/ml, sodium hyaluronate 1.5mg/ml, sodium chloride, trometamol, hydrochloric acid (ii) Hyabak, unpreserved sodium hyaluronate 0.15% and (ii) Hydrabak – unpreserved sodium chloride 0.9%, sodium dihydrogen phosphate dehydrate, disodium hydrogen phosphate dodecahydrate; in patients with dry eye disease. The study found significant differences between artificial tears in increasing TFT after administration. Product (i) containing Trehalose & sodium hyaluronate increased TFT to 240 minutes compared to product (ii) containing sodium hyaluronate which had a TFT of 40 mins. Hyaluronic acid has been reported to have longer TFT times in previous studies using different measurement techniques. The Trehalose containing product had a significantly longer TFT time thought to be related to Trehalose interaction with lipid membranes and requires further investigation. There was no reported difference in patient satisfaction between the three drops.

Reference

Tear film thickness after treatment with artificial tears in patients with moderate dry eye disease.
Schmidl D, Schmetterer L, Witkowska KJ, et al.
CORNEA
2015;34:421-6.

CURRENT EYE RESEARCH

Nicotine accelerates diabetes induced retinal changes
Reviewed by: Khadijah Basheer
Vol 22 No 1
 

This study investigated the influence of nicotine in an experimentally induced diabetic rat model. They used non-invasive high-resolution spectral domain optical coherence tomography (SD-OCT) imaging to provide quantitative information on the temporal alterations of retinal structures at the micrometer resolution level. Cigarette smoking has been associated with progression of diabetic retinopathy and nicotine alone has been shown to promote pathological effects on the retinal pigment epithelium, photoreceptors and cells in the outer nuclear layer in mice. Chronic nicotine toxicity has also been proven to increase the severity of induced choroidal neovascularisation, diabetic nephropathy and cataract development in rat models. The nicotine treatment group in this study demonstrated an average decrease in total retinal thickness of 9.4μm where the loss was mainly in the outer nuclear layer. In the combined nicotine and diabetes group they measured an increase in total retinal thickness, thought to represent a synergistic relationship between hyperglycaemia and nicotine leading to increased fluid retention within the retina, appearing as diabetic macular oedema. One explanation could be that smoking causes a reduction in blood flow due to vasoconstrictive effects of nicotine and hypoxia due to diabetes may perturb auto-regulation leading to oedema. These findings may be important in encouraging patients who smoke or use products containing nicotine to cease to prevent amongst other health risks, the worsening of diabetic retinopathy.

Reference

Nicotine accelerates diabetes-induced retinal changes.
Boretsky A, Gupta P, Tirgna N, et al.
CURRENT EYE RESEARCH
2015;40(4):368-77.

CURRENT EYE RESEARCH

Optic nerve head perfusion response to reduced blood pressure and increased intraocular pressure
Reviewed by: Khadijah Basheer
Vol 22 No 1
 

The purpose of this prospective study was to test the hypothesis that blood flow autoregulation in the optic nerve head has less reserve to maintain normal blood flow where there is a blood pressure induced decrease in ocular perfusion pressure compared to an intraocular pressure induced decrease. They measured the optic nerve head blood flow in two groups of anaesthetised primates, one group had their blood pressure reduced by administration of pentobarbital, the second group had their intraocular pressure increased via an anterior chamber reservoir. Their results showed that optic nerve head blood flow was significantly different between the two groups, showing a greater decline in the blood pressure group. This vulnerability of the optic nerve head to low blood pressure adds to the evidence related to the haemodynamic pathophysiology in glaucoma and ophthalmologists should take this into account in the clinical setting.

Reference

Optic nerve head blood flow response to reduced ocular perfusion pressure by alteration of either the blood pressure or intraocular pressure.
Wang L, Cull GA, Fortune B.
CURRENT EYE RESEARCH
2015;40(4):359-67.

JOURNAL OF CATARACT AND REFRACTIVE NEWS

Closed-chamber haptic re-externalisation for posteriorly displaced sclerotomy and inadequate haptic tuck in glued posterior chamber intraocular lenses
Reviewed by: Sharmina Khan
Vol 22 No 1
 

This technique (online video http://jcrsjournal.org) emphasises the importance of both symmetrical and sufficient anterior placement of sclerotomies to externalise an adequate length of the haptics, which in turn provides good centration and stability of the intra-ocular lens (IOL). The authors describe a secondary procedure to address sclerotomies that haven’t been placed too posteriorly or asymmetric and resulted in IOL tilt. A new sclerotomy is created anterior to the first, avoiding engaging the iris root by turning off the anterior chamber maintainer (AMC) to prevent posterior bowing of the iris. A sharp needle is pointed down through the sclera and into the posterior chamber and then horizontally immediately behind the iris plane in the vitreous cavity. Through a side-port and using micro forceps the haptic is internalised into the eye. The ACM is turned off and a second micro forceps is passed through the anteriorly placed sclerotomy, the haptic grasped and brought out through the anteriorly placed sclerotomy, then tucked into an intra-scleral tunnel. A 26-gauge needle is used to create the intra-scleral tunnel. The advantage of this technique is that it avoids IOL explantation and increases the overall haptic length available for tucking.

Reference

Closed-chamber haptic reexternalization for posteriorly displaced sclerotomy and inadequate haptic tuck in glued posterior chamber intraocular lenses.
Jacob S, Agarwal A, Agarwal A, Narasimhan S.
JOURNAL OF CATARACT AND REFRACTIVE NEWS
2015;41:268-71.

JOURNAL OF CATARACT AND REFRACTIVE NEWS

Toric intraocular lens rotation related to the capsulorrhexis
Reviewed by: Sharmina Khan
Vol 22 No 1
 

The risk factors for postoperative rotation in the early post-operative period; a longer axial length, younger patients, and with the rule astigmatism as described by Miyake T et al. (JCRS 2014) in a case series of six eyes. This letter adds that a capsulorrhexis, larger than the size of the optic is an additional risk factor for post-operative rotation. The authors of the letter identify that in four out of six of Miyake’s cases the capsulorrhexis was larger than the size of the optic. Miyake responds that a large capsulorrhexis is a risk factor for late postoperative rotation. The ideal capsulorrhexis is 0.5mm smaller than the optic diameter. The anterior and posterior capsule fuse with the intraocular lens (IOL) minimising postoperative rotation. Fibronectin plays a major role in IOL-capsular bag adhesion.

Reference

Toric intraocular lens rotation related to the capsulorrhexis.
Leonardo Torquetti.
JOURNAL OF CATARACT AND REFRACTIVE NEWS
2015;41(2):483.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Amniotic membrane efficacy
Reviewed by: Fiona Rowe
Vol 22 No 1
 

This prospective randomised study evaluated the effect of amniotic membrane (AM) in reducing inflammation, fibrosis, adhesion formation and ocular movement restrictions following strabismus surgery. This study used 22 rabbits: all with superior rectus recession in both eyes with AM placed in the right eye only. Dynamometer tests were undertaken at 15 days post-surgery in 17 rabbits after which the rabbits were killed and orbits exenterated. The same was undertaken for five rabbits but at 30 days post-surgery. At 15 days post-surgery, inflammation levels of eyes with AM were statistically greater than eyes without AM and fibrosis levels were lower for eyes with AM. At 30 days post-surgery, inflammation levels were statistically greater and fibrosis levels lower. At 15 days, dynamometer tests showed that greater force was needed to displace eyes without AM. This was not significant at 30 days. Further study is required to confirm the increased inflammatory response due to use of human AM in rabbits.

Reference

Amniotic membrane for reducing the formation of adhesions in strabismus surgery: experimental study in rabbits.
Kirsch D, Lowen MS, Cronemberger MF, Sato EH.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51(6):341-7.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Atropine penalisation for amblyopia in the UK
Reviewed by: Fiona Rowe
Vol 22 No 1
 

The authors aimed to determine the current clinical practice of atropine penalisation (AP) in the UK, to identify perceived barriers limiting use of AP as a first line treatment and ascertain whether any of the barriers could be resolved. An anonymised online survey was distributed through the UK professional society for orthoptists (BIOS). Responses were obtained from 151 orthoptists (13% return). Seventy-one percent indicated they had department protocols regarding the use of AP. Twenty-five percent used AP as the first line of treatment for amblyopia. Children younger than seven years were most commonly targeted. Its use was considered in more moderate to severe density of amblyopia. Eighty-nine percent would stop treatment if no improvement in visual acuity was noted over three consecutive visits. Forty-eight percent favoured daily atropine, 41% alternate day, 29% weekend use and 9% weekly use. Reported recognised side-effects included skin rash / flushing, mood changes, eye irritation / pain. Barriers to use included department-specific problems with use of AP, inability to prescribe and inability to obtain atropine. The survey showed that the percentage of orthoptists offering AP as a first line treatment has increased. It was avoided in older children because of perceived risks of intractable diplopia. Orthoptists still raise concerns regarding general efficacy, side-effects and reverse amblyopia.

Reference

Use of atropine penalisation to treat amblyopia in UK orthoptic practice.
Piano M, Newsham D, O’Connor AR.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51(6):363-9.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Collamer lenses for accommodative ET
Reviewed by: Fiona Rowe
Vol 22 No 1
 

Posterior chamber phakic IOL implantation was used to treat patients with accommodative esotropia (ET) with the goal of eliminating hyperopia and producing orthophoria. Three patients (six eyes) aged 18-22 years had an average follow-up of 17 months ±6.24. The mean preoperative spherical equivalent cycloplegic refraction was 6.04D ±0.53 and postoperative refraction of 0.41D ±0.21. This was stable over the follow-up period. All three achieved orthophoria or microesophoria postoperatively. Postoperative corneal oedema occurred in one case which recovered rapidly. One patient complained of postoperative glare which reduced over time. Preliminary results show that IOL implantation for accommodative esotropia is safe, effective, predictable and stable with low incidence of postoperative complications and positive patient satisfaction. Further large scale studies are recommended.

Reference

Treatment of adults with accommodative esotropia using implantable collamer lenses.
Shi M, Jiang H, Ye Y, Chen B.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:31-6.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Cyanoacrylate vs. fibrin glue
Reviewed by: Fiona Rowe
Vol 22 No 1
 

This study compared the safety and efficacy of fibrin and cyanoacrylate glue for refixating the recessed muscle to the sclera in patients undergoing strabismus surgery. The fibrin group (a) included 21 eyes of 15 patients; mean age of 11.6 ±7.49 years. The cyanoacrylate group (b) included 19 eyes of 15 patients; mean age of 12.4 ±9.98 years. Both groups were comparable for age. Each group consisted of eight males and seven females. The average time per muscle attachment was 1.48 ±0.69 minutes (group a) and 2.42 ±0.58 minutes (group b). Postoperative alignment within 10PD was achieved in every patient at six weeks. One patient developed consecutive exotropia at three months. There was no significant difference in pain between groups. Group b had significantly more chemosis with conjunctival reaction and total inflammation score. Two patients in group b developed localised granuloma formation over the site of muscle reattachment and required surgical removal of this. Both glues were equally efficacious for muscle reattachment but there were clear issues with cyanoacrylate. The authors recommend fibrin glue as a safe, effective and bio tolerant alternative to sutures and cyanoacrylate glue for recessions in strabismus surgery.

Reference

Comparative evaluation of cyanoacrylate and fibrin glue for muscle recession in strabismus surgery.
Topiwala P, Bansal RK.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51(6):349-54.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

IO surgery
Reviewed by: Fiona Rowe
Vol 22 No 1
 

The purpose of this paper was to evaluate the efficacy of a new surgical technique in reducing inferior oblique muscle overaction (IOOA) consisting of suturing the muscle to the sclera at the Gobin point with tendon sparing and using a micro incision to minimise related tissue trauma. Eight patients aged 5-51 years were included. At four months postoperative the mean angle reduced to 8PD exotropia in five patients with a V-exotropia. One patient with unilateral IOOA had reduced from 18 to 3PD vertical deviation. Two patients with infantile esotropia had complete resolution of elevation in adduction with no vertical imbalance. All had improvement in lateral incomitance. The authors propose the technique as simple, safe, reversible and modular in terms of suturing. They propose additional benefits of little risk to developing vorticose haemorrhage or macular damage, no errors in IO muscle hooking and no risk of anti-elevation syndrome.

Reference

New surgical intervention for the weakening of the inferior oblique muscle: equatorial scleral anchor.
Tomarchio S, Sabetti L, Tomarchio M, Berarducci A.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:58-60.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Management of congenital NLD obstruction
Reviewed by: Fiona Rowe
Vol 22 No 1
 

The authors evaluated changes in management of congenital nasolacrimal duct obstruction (CNLDO) by surveying 1495 Association for Paediatric Ophthalmology & Strabismus (AAPOS) members. The survey consisted of 21 multiple choice questions with anonymised return. Responses were received from 127 members and six were excluded as potentially biased. A total of 84% were completed by North American members and 16% by international members which was reflective of the AAPOS organisational membership. Ninety-five percent regularly treat CNLDO. For treatment in the first year of life 45% perform the Crigler manoeuvre on the initial visit for infants younger than six months. Of these 82% instruct carers to massage the duct and 17% offer office probing but this is significantly more for those with >10 years’ experience. Surgical treatment includes 79% recommending surgery from 13 months of age for unresolved cases, and 12% for infants aged 10-12 months. Seventy-nine percent chose probing as their primary treatment. In children with first surgery at age two years, 53% chose non-probing procedures. For children aged three years at first procedure, 67% chose non-probing procedures. For failed probing, most opted for silicone intubation with or without balloon dacryoplasty. With silicone intubation, 64% preferred monocanalicular tubes typically left in place for three to four months. For bicanalicular tubes, most were removed in the office and the remainder in the operating room. With regard to risk of amblyopia, 91% regularly check refraction at the initial visit and 45% recheck when aged one to two years. This study found a striking lack of consensus among ophthalmologists.

Reference

Congenital nasolacrimal duct obstruction: common management policies among pediatric ophthalmologists.
Dotan G, Nelson LB.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:14-9.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Postop improved fusion and stereopsis in IDEX
Reviewed by: Fiona Rowe
Vol 22 No 1
 

This study aimed to evaluate changes in binocular visual function in patients with different ages before and after surgery to explore the optimal timing of intermittent exotropia surgery. The study comprised 28 females and 25 males. Fifty-three patients were split into three groups of <7 years, 7-13 years and >13 years. Median age was 6.07, 10.82 and 16.298 years respectively. They were examined preoperatively and at two and six weeks postoperatively. A total of 32% had a family history of strabismus and 38% had their strabismus detected during routine physical examination. The angle of deviation at near and distance significantly increases with older age with median angles of 55, 45 and 85PD respectively for the three groups at near fixation and 37.5, 40 and 80PD at distance fixation. Near stereoacuity improved significantly as did distance stereoacuity. Peripheral and central fusion improved postoperatively and improvement was noted across all age groups. The authors propose that surgery for intermittent exotropia can be postponed appropriate to the case.

Reference

Improvement in fusion and stereopsis following surgery for intermittent exotropia.
Feng X, Zhang X, Jia Y.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:52-7.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Refocus on children programme results
Reviewed by: Fiona Rowe
Vol 22 No 1
 

The authors describe the logistics and results of the refocus on children programme for the 2012-13 school year. The aim of the programme was to help school nurses provide access to comprehensive vision care and reduce unnecessary visual loss or impairment. The programme was designed to reach children in 23 low income schools. The Plusoptix screener was used and 2750 children were successfully screened. Of that 741 were referred (27%). Consent for further examination was obtained for 419 children and 192 were given glasses. There was a 49% response rate to the request for feedback from teachers for these children. Children receiving glasses typically wore them regularly. A total of 70% of teachers reported that children liked their glasses. Positive comments from teachers included reduced squinting, better vision, improved academic performance, and improved child focus on lessons, improved participation and interaction. Negative comments included children being embarrassed to wear glasses, taking poor care of glasses and glasses being used as a toy. Overall the study examined 56% of children referred. As the process was completed at school, the students received the support of the entire team which helped with wearing new glasses. Half of the children referred needed glasses.

Reference

Combining automated vision screening with on-site examinations in 23 schools: ReFocus on Children Program 2012 to 2013.
Peterseim MM, Papa CE, Parades C, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2015;52:20-4.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Treatment of infantile cataract with secondary IOLs
Reviewed by: Fiona Rowe
Vol 22 No 1
 

The authors examined whether secondary IOL insertion is helpful in the successful treatment of monocular infantile cataracts. Eleven children were reviewed: eight with cataract extraction at one to four months of age and three at five to seven months of age. Secondary posterior chamber IOL insertion was undertaken at one to six years. Surgery for the one to four month infants resulted in obtaining visual acuities of ≥20/150 in 87.5%. One child developed stereopsis. Surgery for the five to seven month infants showed that poor visual acuity prior to IOL implantation remained poor. Contact lens and patching compliance markedly affected final visual acuity. The quality of aphakic correction and patching combined had the best effect. The authors conclude that cataract extraction with proper patching and use of aphakic contact lenses prior to four months of age with compliance for at least one year results in better outcomes / insertion of secondary IOLs will maintain vision.

Reference

The role and efficacy of secondary intraocular lenses in the treatment of monocular infantile cataracts.
Kruger TL, Monson BS, Baker JD.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51(6):370-4.

NEURO-OPHTHALMOLOGY

Literature review of isolated ocular motor nerve palsies
Reviewed by: Claire Howard
Vol 22 No 1
 

Patients aged over 50 presenting with isolated nerve palsies of the third (pupil sparring), fourth or sixth nerves, are often described as having microvascular extraocular palsies. This review looks critically at the evidence surrounding these microvascular non-arteritic extraocular palsies and suggests practical ideas on diagnosis and management of suspected cases. The condition itself and its management provoke divergent opinions. The review covers a wide range of features including incidence, pathology, causes, clinical presentation, and yield of imaging, progression, recovery as well as management options. The literature review demonstrates that the clinical presentation is more diverse than often thought. According to the authors, the two crucial differential diagnoses that must be considered immediately in an isolated ocular motor palsy are giant cell arteritis and posterior communicating artery aneurysm. Overall the authors suggest a pragmatic approach to diagnosis, investigation and management from initial presentation.

Reference

Microvascular non-arteritic ocular motor nerve palsies – what we know and how should we treat?
Galtrey CM, Schon F, Nitkunan A.
NEURO-OPHTHALMOLOGY
2015;39(1):1-11.

NEURO-OPHTHALMOLOGY

Long-term retinal changes following unilateral retrobulbar optic neuritis
Reviewed by: Claire Howard
Vol 22 No 1
 

The aim of this study was to assess the longitudinal changes in retinal nerve fibre layer (RNFL) thickness after a first attack of optic neuritis and to investigate the impact of treatment on RNFL thinning at one year after the attack. RNFL thickness of the attack and normal fellow eyes was measured by optical coherence tomography on presentation and three, six and 12 months post attack in treatment and non-treatment groups. The treatment group consisted of subjects that opted for systemic steroids to hasten recovery time, patients were not randomised into the groups. Findings showed that the baseline RNFL thickness was similar in the attack and fellow eyes. Progressive RNFL thinning was seen in the attack eye over the 12 month period. Importantly, the RNFL thickness was similar between the treatment and non-treatment groups. This has clinical significance for the treatment offered to patients following unilateral retrobulbar optic neuritis. In this study, initial treatment with systemic steroids did not alter the degree of RNFL loss at 12 months, suggesting that the treatment was ineffective. Before treatment using steroids is discarded, however, a large sample size randomised control trial is required to investigate the effectiveness of treatment in full.

Reference

Longitudinal changes in retinal nerve fibre layer thickness after an isolated unilateral retrobulbar optic neuritis: 1 year results.
Yau GSK, Lee JWY, Lau PPK, et al.
NEURO-OPHTHALMOLOGY
2015;39(1):22-5.

NEURO-OPHTHALMOLOGY

Structural effects of migraine on the retina
Reviewed by: Claire Howard
Vol 22 No 1
 

Migraine is a common, chronic, multifactorial neuro-vascular disorder typically characterised by recurrent attacks of disabling headache and autonomic nervous system dysfunction (migraine without aura). Up to one third of patients also have neurological aura symptoms (migraine with aura). The objective of this study was to evaluate the retinal nerve fibre layer (RNFL) thickness in migraine patients with or without aura and to search for possible structural effects of migraine on the retina. Parameters related to RNFL thickness of right and left eyes’ average superior, inferior, nasal and temporal quadrant values were found to be similar in migraine and control subjects. When focusing on the RNFL thickness of right and left eyes and the migraine parameters, there were no significant differences between migraine sufferers with and without aura. The overall conclusion from the study was that migraine disease with or without aura does not have any effect on the thickness of the RNFL.

Reference

Retinal nerve fibre layer thickness in migraine patients with or without aura.
Bahceci Simsek I, Aygun D, Yildiz S.
NEURO-OPHTHALMOLOGY
2015;39(1):17-21.

OPHTHALMIC EPIDEMIOLOGY

Are retinal vein occlusions seasonal? And if so why might that be?
Reviewed by: Jonathan C P Roos,
Vol 22 No 1
 

Some studies have reported a strong seasonal pattern to central retinal vein occlusion (CRVO) occurrence with a peak in January, but other studies have failed to replicate this finding. The authors sought to determine data for Stockholm’s seasonal variation in CRVOs and retrospectively reviewed the charts of all patients presenting to the main Stockholm eye hospital – St Eriks – between 2008 and 2013. There were 854 such cases in the study period with an incidence of 2/10,000 in the over 40, and 7/10,000 in the over 85 year group. Attendance records showed a peak in the late winter / early spring period which was significantly higher than the late summer / early autumn (p<0.0002). Could it be that Swedes are too busy sailing in the archipelago to bother about sight loss in the summer? Or do the cold winters freeze their eyes? The authors suggest a number of possible explanations to account for this finding. Cold temperatures have been shown to be able to result in increased blood viscosity and clotting factors, and blood pressure too has been reported to increase during the winter months. However, the most compelling reason given is that Vitamin D levels slowly run out during the winter months and the timing of the lowest level of Vitamin D coincides with the highest rate of CRVO. Could this just be a coincidence? Though causality cannot be proven, a recent meta-analysis has shown that low Vitamin D levels are associated with high blood pressure and endothelial dysfunction including changes to clotting factors. The authors cite a study in which patients at increased risk of CRVO (type II diabetics) were given Vitamin D supplements and this improved their blood pressure and endothelial cell responsiveness to changes in flow. At the moment this all remains speculative, but fascinating.

Reference

Seasonality and incidence of central retinal vein occlusion in Sweden: a 6-year study.
Epstein D, Kvanta A, Lindqvist PG.
OPHTHALMIC EPIDEMIOLOGY
2015;22(2):94-7.

OPHTHALMIC EPIDEMIOLOGY

Is an increased homocysteine level associated with greater risk of AMD?
Reviewed by: Jonathan C P Roos
Vol 22 No 1
 

Basic research studies have implicated homocysteine in causing vascular endothelial dysfunction and inflammation, and this has been borne out in large observational studies which suggested that elevated homocysteine is associated with increased risk of cardiovascular disease. In order to determine whether there might be an association also between age-related macular degeneration (AMD) and homocysteine, Christen et al. prospectively studied a cohort of healthy female health professionals over the age of 40 from the Womens Health study. This was a large study involving 27,479 persons followed up over 10 years. Four hundred and fifty-two developed AMD, of which 182 were visually significant. The study authors did not find statistically significant evidence to suggest that elevated homocysteine levels were associated with an increased risk of developing AMD, nor was there a correlation for the subset with visually significant AMD (worse than 20/30). This large prospective study suggests that homocysteine levels do not contribute greatly to the risk of developing AMD.

Reference

Prospective study of plasma homocysteine level and risk of age-related macular degeneration in women.
Christen WG, Cook NR, Ridker PM, Buring JE.
OPHTHALMIC EPIDEMIOLOGY
2015;22(2):85-93.

OPHTHALMIC EPIDEMIOLOGY

Which factors predispose to pingecula development in a rural Chinese population?
Reviewed by: Jonathan C P Roos
Vol 22 No 1
 

The authors report a cross-sectional study which aimed to determine the prevalence and risk factors for developing pingecula in a rural Chinese population near Shanghai. Nine hundred and fifty-nine persons were recruited from a single village and asked to complete a questionnaire detailing their medical and social history and were then examined by slit-lamp to determine whether pingecula were present. The prevalence was high with 75% of patients being found to have pingecula. Next the authors performed regression analysis to determine whether sex, educational attainment, smoking, alcohol consumption, tear break-up time, age or sunlight exposure might be associated with an increased risk of pingecula formation. Only the last two were found to be statistically associated (age p<0.002) and sunlight (more than two hours per day p<0.001).

Reference

Prevalence and associated factors of pinguecula in a rural population in Shanghai, Eastern China.
Le Q, Xiang J, Cui X, et al.
OPHTHALMIC EPIDEMIOLOGY
2015;22(2):130-8.

OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY

The dynamic nature of orbital cavernous haemangiomas
Reviewed by: James Hsuan
Vol 22 No 1
 

This paper seeks to address the question of how much do orbital cavernous haemangiomas actually change over time, and if there are any identifiable factors which can predict which lesions will grow and which will remain stable. In particular, if a haemangioma was found incidentally are there any factors which can predict the likelihood of it requiring surgery in the future? The clinical records and images were reviewed of 104 patients with cavernous haemangiomas, 31 of these had been incidental findings. In all, 79 patients required surgical intervention. This included 11 from the incidentally diagnosed group who unsurprisingly had less proptosis and were smaller at diagnosis than the symptomatic group. For all haemangiomas, factors predictive of needing surgery were greater size, choroidal folds, being male and extraconal location, but no factors were found which could predict which of the incidental lesions were more likely to grow. Overall the incidentally found lesions were less likely to require surgery, and most were either stable or grew at less than 1mm a year. Despite this, 35% of these did require surgery within five to six years of diagnosis. Symptoms which led to surgery included reduced acuity, diplopia and increasing proptosis. The authors advise regular observation and imaging initially, but if incidental lesions are stable for five years they are very likely to remain stable in the long-term. This is an extensive multicentre review with useful data regarding the management of asymptomatic, incidentally found cavernous haemangiomas, and will help when advising patients on the likelihood of needing surgery in the future.

Reference

The natural history of orbital cavernous hemangiomas.
McNab AA, Tan JS, Xie J, et al.
OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY
2015;31:89-93.

OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY

Wide variation in the volume of the sphenoid trigone
Reviewed by: James Hsuan
Vol 22 No 1
 

This is a radiological study of the volume of the sphenoid trigone in normal subjects. The authors were interested to see how much volume could be gained by removal of the trigone during an orbital decompression for thyroid eye disease. Specifically, they were looking at the natural anatomical variation and differences due to gender or race. CT scans from 120 normal subjects were found with 40 each from three racial groups; Asian, black/African American and white. Each group had 20 males and females, all aged 30-60. Both orbits of each subject were analysed to measure the volume of the trigone by measuring the area of the trigone in every 2mm axial slice between the superior and inferior orbital fissures. These areas were then summed and multiplied by two (the slice thickness) to give the volume. The mean volume overall was 1.53 cm³ with a range of 0.2 to 4.4 cm³. Male subjects had a significantly larger mean volume than females but there was no significant difference between races. Interestingly, right trigones were significantly smaller than left. An important finding emphasised by the authors is the very wide natural range in volumes, with some subjects having 10 times the volume of others within the same sub-group. Furthermore there can even be large differences between the two orbits in the same subject, with the trigone on one side having twice the volume of the other. Understanding this extreme variability is important in planning decompression surgery and the paper makes this point clearly with good supporting data.

Reference

CT-based measurements of the sphenoid trigone in different sex and race.
Lefebvre DR, Yoon MK.
OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY
2015;31:155-8.

OPHTHALMIC RESEARCH

Influence of overall intraocular lens diameter on rotational stability
Reviewed by: Bheemanagouda Pati
Vol 22 No 1
 

It has been shown that approximately one in three patients undergoing cataract surgery have >1.0D corneal astigmatism and managing this during surgery is important to achieve good refractive outcomes. One of the widely used ways of reducing preoperative astigmatism during cataract surgery is by using toric intraocular lenses (IOL). It is ideal if this lens has minimal or no postoperative rotation. The aim of this study was to determine the influence of the overall IOL diameter on rotational stability. The IOLs used in this study were ACR6 (12mm) and IDEA 613 XC (13mm) (both CromaPharm GmbH., Austria). Both these IOLs are monofocal, hydrophilic acrylic single-piece with water content of 26%. For the study, all IOLs had markings on them to determine rotational stability postoperatively, but were spherical in design. Sixty eyes of 60 patients were included in the study. Eighteen patients were lost to follow-up at the three month visit. Absolute rotation in the small and large diameter IOL groups was 4.4º (SD: 4.0; range: 0.3-17.8) and 3.0º (SD: 2.4; range: 0.1-7.8) respectively. The differences between the two IOLs were not found to be statistically significant. Thus the authors concluded that the effect of the overall length of an IOL appears to have little impact on early rotation after cataract surgery.

Reference

Influence of the overall intraocular lens diameter on rotational stability.
Harrer A, Hirnschall N, Maedel S, Findl O.
OPHTHALMIC RESEARCH
2015;53(3):117-21.

OPHTHALMOLOGICA

RaScaL Study
Reviewed by: Sofia Rokerya
Vol 22 No 1
 

The RaScaL study was a six month, single-centre, controlled, prospective phase I/II study in which subjects with diabetic macular oedema (DME) and associated peripheral nonperfusion on ultrawide-field fluorescein angiography (UWFA) were randomised to: (1) study arm: ranibizumab (0.5 mg) injection plus UWFA-guided peripheral scatter laser, or (2) control arm: triamcinolone acetonide (4.0 mg) injection plus macular laser (focal / grid).The study population consisted of 22 patients (30 eyes, eight bilateral patients) ≥18 years of age with type 1 or 2 diabetes mellitus glycosylated hemoglobin (HbA 1c ) ≤12%, and visual impairment due to DME. The key inclusion criteria were: (1) stability of diabetes within three months; (2) visual impairment due to DME in at least one eye that was eligible for macular laser treatment in the opinion of the investigator, and (3) peripheral nonperfusion on UWFA of at least three clock hours. Mean initial Early Treatment Diabetic Retinopathy Study and best corrected visual acuity (ETDRS BCVA) was 54 letters (20/80) in the control and 59 letters (20/60) in the RaScaL group. Mean central foveal thickness (CFT) on optical coherence tomography (OCT) was 473 in the control group and 493 in the RaScaL group. Both the RaScaL and the control (combination intravitreal triamcinolone acetonide 4.0mg plus macular laser) groups achieved visual acuity improvements at six months, of 13 and 10 letters, respectively. None of the RaScal patients suffered a loss of visual acuity at six months. There was also improvement in the CFT on OCT in both groups with a trend for less thickening in the RaScaL group (279 vs. 367μm). The RaScaL group trended to a more gradual but consistent improvement in visual acuity and CFT; conversely, the control group of triamcinolone plus macular laser demonstrated a trend toward earlier improvement in initial visual acuity and OCT but later recurrence of DME. The RaScaL group required rescue treatment for recurrent DME in only 33% of patients at six months as compared to 80% in the control group. This difference was clinically and statistically significant (p<0.003). This finding supports the hypothesis that this subgroup of DME may have an underlying pathobiology significantly driven by peripheral retinal ischaemia, resulting in VEGF production, and ultimately leading to increased permeability of the retinal vasculature in the macula. As a result, treatment with this approach of peripheral scatter laser and VEGF inhibition may result in better durability, decreased burden of injections, and long-term control in this subset of patients with DME. Decision by imaging signatures is an attractive concept that requires further trials. This study was limited by its small size, slight imbalance in baseline visual acuity between groups and limited follow-up and imaging technology. Although Optos P200MA provides excellent, reliable, reproducible images through small pupils, however, the view of the anterior periphery and the superior and inferior views may be limited by the lids or lashes. Through six months of follow-up, this small pilot study suggests that the RaScaL treatment strategy consisting of ranibizumab plus UWFA-guided peripheral scatter laser may be a reasonable therapeutic approach in treating patients with DME associated with peripheral retinal nonperfusion.

Reference

RaScaL: single intervention with ranibizumab plus peripheral laser for diabetic macular edema associated with peripheral nonperfusion on ultrawide-field fluorescein angiography.
Suñer I, Peden M, Hammer M, et al.
OPHTHALMOLOGICA
2015;233:89–95.

RETINA

ILM peeling in primary rhegmatogenous retinal detachment
Reviewed by: Saruban Pasu
Vol 22 No 1
 

This author retrospectively analysed the correlation between internal limiting membrane (ILM) peeling and the occurrence of a postoperative epiretinal membrane (ERM) in patients who underwent vitrectomy for rhegmatogenous retinal detachment (RD). There were 135 medical records investigated. Seventy patients underwent ILM peeling, 65 did not. Patients found to have an ERM at the time of surgery were excluded. At 12 month follow-up, no ERM was identified in the ILM peel group, whereas ERM was observed in 14 of 65 patients in the non ILM peel group. Removing the ILM can remove the ERM precursor cells from the retinal surface. ERM occurred in 12 of the 14 patients (85.7%) within three months of the RD surgery. The authors found no significant correlation between ERM development and age, best corrected visual acuity (BCVA) at initial diagnosis, macular involvement, break location, number, shape, RD extent, or gas type in non-ILM peeling patients. Although ILM peeling has been shown to prevent ERM formation post RD repair, the authors conclude that a longer term prospective study with a greater number of patients is needed to provide evidence that ILM peeling in all patients is beneficial.

Reference

Effect of internal limiting membrane peeling on the development of epiretinal membrane after pars plana vitrectomy for primary rhegmatogenous retinal detachment.
Nam KI, Kim JY.
RETINA
2015;35:880-5.

RETINA

OCT positioning regimen in macular hole surgery
Reviewed by: Saruban Pasu
Vol 22 No 1
 

The authors set out to evaluate an OCT-based positioning regimen for macular hole surgery. Patients were advised to maintain prone positioning until the hole was confirmed to be closed based on daily OCTs. Surgery consisted of 23-gauge phacovitrectomy with internal limiting membrane (ILM) peel and 20% SF6. A retrospective case note review was carried out on 33 patients (35 eyes) who had undergone this regimen. Mean baseline visual acuity was 20/220 with a mean hole size of 465 microns. Seventeen percent were diagnosed with myopic degeneration, while 37% were found to have chronic holes (more than or equal to 12 months duration). Day one OCT images were obtained in 89%, day two in 97% and day three in 100% of eyes. The authors suggest to obtain clear OCT images in gas filled eyes, the focus on the OCT machine should be set between -10D and -20D. Closed holes began to reopen by the first postoperative week. Eighty-nine percent were closed on day seven, 83% closed on day eight to 14, 80% were closed one month after surgery. Three percent did not close postoperatively, 9% reopened at two weeks, 3% reopened at four weeks and 3% at six weeks. Risk factors for failure to maintain closure were identified as large holes, chronic holes and myopic degeneration. The authors suggest if the patient has no risk factors, positioning can be stopped once the hole has closed. If the patient has one risk factor, advice to position can be extended for a few days after hole closure. If the patient has two or three risk factors, seven days of prone positioning even if the hole is closed on day one is recommended using this OCT based positioning regimen.

Reference

Optical coherence tomography – based positioning regimen for macular hole surgery.
Chow DR, Chaudhary KM.
RETINA
2015;35:899-907.

RETINA

OCT positioning regimen in macular hole surgery
Reviewed by: Saruban Pasu
Vol 22 No 1
 

The authors set out to evaluate an OCT-based positioning regimen for macular hole surgery. Patients were advised to maintain prone positioning until the hole was confirmed to be closed based on daily OCTs. Surgery consisted of 23-gauge phacovitrectomy with internal limiting membrane (ILM) peel and 20% SF6. A retrospective case note review was carried out on 33 patients (35 eyes) who had undergone this regimen. Mean baseline visual acuity was 20/220 with a mean hole size of 465 microns. Seventeen percent were diagnosed with myopic degeneration, while 37% were found to have chronic holes (more than or equal to 12 months duration). Day one OCT images were obtained in 89%, day two in 97% and day three in 100% of eyes. The authors suggest to obtain clear OCT images in gas filled eyes, the focus on the OCT machine should be set between -10D and -20D. Closed holes began to reopen by the first postoperative week. Eighty-nine percent were closed on day seven, 83% closed on day eight to 14, 80% were closed one month after surgery. Three percent did not close postoperatively, 9% reopened at two weeks, 3% reopened at four weeks and 3% at six weeks. Risk factors for failure to maintain closure were identified as large holes, chronic holes and myopic degeneration. The authors suggest if the patient has no risk factors, positioning can be stopped once the hole has closed. If the patient has one risk factor, advice to position can be extended for a few days after hole closure. If the patient has two or three risk factors, seven days of prone positioning even if the hole is closed on day one is recommended using this OCT based positioning regimen.

Reference

Optical coherence tomography – based positioning regimen for macular hole surgery.
Chow DR, Chaudhary KM.
RETINA
2015;35:899-907.

RETINA

OCT positioning regimen in macular hole surgery
Reviewed by: Saruban Pasu
Vol 22 No 1
 

The authors set out to evaluate an OCT-based positioning regimen for macular hole surgery. Patients were advised to maintain prone positioning until the hole was confirmed to be closed based on daily OCTs. Surgery consisted of 23-gauge phacovitrectomy with internal limiting membrane (ILM) peel and 20% SF6. A retrospective case note review was carried out on 33 patients (35 eyes) who had undergone this regimen. Mean baseline visual acuity was 20/220 with a mean hole size of 465 microns. Seventeen percent were diagnosed with myopic degeneration, while 37% were found to have chronic holes (more than or equal to 12 months duration). Day one OCT images were obtained in 89%, day two in 97% and day three in 100% of eyes. The authors suggest to obtain clear OCT images in gas filled eyes, the focus on the OCT machine should be set between -10D and -20D. Closed holes began to reopen by the first postoperative week. Eighty-nine percent were closed on day seven, 83% closed on day eight to 14, 80% were closed one month after surgery. Three percent did not close postoperatively, 9% reopened at two weeks, 3% reopened at four weeks and 3% at six weeks. Risk factors for failure to maintain closure were identified as large holes, chronic holes and myopic degeneration. The authors suggest if the patient has no risk factors, positioning can be stopped once the hole has closed. If the patient has one risk factor, advice to position can be extended for a few days after hole closure. If the patient has two or three risk factors, seven days of prone positioning even if the hole is closed on day one is recommended using this OCT based positioning regimen.

Reference

Optical coherence tomography – based positioning regimen for macular hole surgery.
Chow DR, Chaudhary KM.
RETINA
2015;35:899-907.

SEMINARS IN OPHTHALMOLOGY

Effect of anti-VEGF treatment on PED morphology
Reviewed by: Jayavani Myneni,
Vol 22 No 1
 

This retrospective study of 30 eyes assessed the effect of anti-VEGF on morphology of pigment epithelial detachments (PED) secondary to age-related macular degeneration (AMD). Thirty eyes of 28 patients with PED were compared to 30 eyes of 30 patients with AMD without PED component. The subjects in both groups were individually matched for gender, BCVA before treatment with anti-VEGF, follow-up period and age. All patients received ranibizumab monthly for the first three months followed by PRN treatment. Mean follow-up period was 19.8 months. Morphological changes of PED on OCT were qualitatively assessed by three masked investigators. OCT scans of the same orientation were chosen for comparison only if there was agreement among the three investigators. These changes were correlated with improvements in BCVA. Number of injections and BCVA were compared among the two groups. Extent of PED when compared to baseline were graded as unchanged in 36.7%, reduced in 40% and significantly reduced in 23.3% of eyes. No eyes showed an increase in size. No evidence was found that improvements in PED correlate to improvements in BCVA. No RPE tear was observed in this study. The limitations of the study are small size of study groups, retrospective comparison, lack of quantitative analysis of PED volume and grouping of all types of PED without classification. This study provides supporting evidence that anti-VEGF therapy stabilises or improves PED extent in wet AMD.

Reference

The effect of intravitreal anti-VEGF on the pigment epithelial detachment in eyes with the exudative type of age-related macular degeneration.
Kalouda P, Anastasakis A, Tsika C, Tsilimbaris KM.
SEMINARS IN OPHTHALMOLOGY
2015;30(1):6-10.

THE NEW ENGLAND JOURNAL OF MEDICINE

How much money is wasted on tests prior to cataract surgery? And why?
Reviewed by: Jonathan C P Roos
Vol 22 No 1
 

For routine cataract surgery, numerous studies have found that preoperative testing does not contribute usefully to safety or surgical success. Despite such guidelines, tests ordered for patients prior to phacoemulsification in the US remains high. To quantify the associated costs, Chen and colleagues studied patients on Medicare – the US federal health insurance system which pays for 80% of cataract surgery in the United States. The authors studied a cohort of patients who had such surgery in 2011, comparing the tests performed in the month prior to surgery with those ordered for the same patient in the preceding 11 months. Patients were identified using billing codes used by Medicare which allowed identification of the practice setting, geographical area and surgeon. There were 500,000 such patients selected randomly. The following tests were considered when ordered a month before surgery: full blood count (FBC), urea & electrolytes (U&Es), Coag screen, urinalysis, ECG, cardiac echo, stress test, chest x-ray and pulmonary function tests. Fifty-three percent of patients had at least one such preoperative test and the excess spend in the month prior to surgery (compared to the 11 month baseline) totalled $17.2million. The main predictive factor for ordering such tests was unrelated to the patient or region: 8% of cataract surgeons ordered preoperative tests on all their patients; 36% ordered preoperative tests for more than 75% of patients. Thirteen percent of patients had one of the tests listed above, 11% had two, 10% three, 7% four and 13% had five or more – and all for routine cataract surgery! Surprisingly the rate had not changed after the introduction of clinical guidelines aimed at curtailing such testing. The authors concluded that preoperative testing represents a significant expense; publishing guidelines does not necessarily alter surgeon behaviour and physicians vary greatly in their practice. Is this relevant to UK ophthalmologists? This study reminds us to be careful guardians of the health budget, to be aware of guidelines’ effects on budgets and illustrates how colleagues abroad approach practice – particularly when transatlantic treaties currently being negotiated at the EU level could possibly put UK practitioners in direct competition with other such providers.

Reference

Preoperative medical testing in medicare patients undergoing cataract surgery.
Chen C, Lin G, Bardach NS, et al.
THE NEW ENGLAND JOURNAL OF MEDICINE
2015;372:1530-8.

AMERICAN JOURNAL OF OPHTHALMOLOGY

Is there an association between dry eye disease and depression and anxiety?
Reviewed by: Efrosini Papagiannuli
Vol 21 No 6
 

Dry eye disease is a widespread ocular surface condition (prevalence 5.5-33.7%) that has been previously linked to systemic diseases, such as Sjogren, rheumatoid arthritis and more recently possibly also depression, in small population-based studies. The authors’ aim was to investigate this association in a large, adult, inclusive study and for this reason conducted a retrospective, case-control review of all patients over 18 years, that were seen in the outpatient setting of a large university hospital between 2008 and 2013. They used diagnostic codes (ICD-9) for dry eyes, depression, anxiety and rheumatoid arthritis (as a validating disease), and utilised these codes to calculate odds ratios separately for dry eyes and each of the other diseases. They applied logistic regression models to estimate associated odds ratios, which was each adjusted for age and sex, along with 95% confidence intervals. A total of 460,611 patients were included, with 7207 patients with dry eyes, 20,004 with anxiety and 30,100 with depression. Seventy-six patients were excluded because age could not be determined. The odds ratios between dry eyes and anxiety were 2.8 (95% CI 2.6, 3.0), and between dry eyes and depression 2.9 (95% CI 2.7, 3.1). The odds ratios between rheumatoid arthritis and dry eyes was 3.2 (95% CI 2.8, 3.7). The authors also found a greater association of dry eyes and rheumatoid arthritis in the younger age group. These findings are statistically significant and confirm the association between dry eyes and anxiety / depression in (so far) the largest population cohort. This may have implications for the healthcare providers to be aware and perhaps initiate screening for these comorbidities in dry eye patients. The authors argue that the major strength of their study is its large and diverse size, which makes the results more generalisable. They also point out the limitations imposed by its retrospective nature, which did not allow any conclusions about causality, and the possibility of confounding factors, such as possible medications that patients were using to treat depression (tricyclic antidepressants being a risk factor for dry eyes due to their anticholinergic effect). The authors recommend further studies assessing the above, as well as the effects of treated depression on the management of dry eyes.

Reference

The association between dry eye disease and depression and anxiety in a large population – based study.
Van der Vaart R, Weaver MA, Lefebvre C, Davis RM.
AMERICAN JOURNAL OF OPHTHALMOLOGY
2015;159(3):470-4.

CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY

Effect of topical diclofenac on postoperative PRK pain: RCT
Reviewed by: Anjali Gupta
Vol 21 No 6
 

A major disadvantage of excimer laser photorefractive keratectomy (PRK) is pain and discomfort after the surgery, which is thought to be due to damage to corneal sensory nerve fibres or local release of inflammatory substances. Pain only resolves once corneal re-epithelialisation is complete. Previous studies have shown that topical nonsteroidal anti-inflammatory drugs (NSAIDS) can cause corneal complications when used excessively and for long time periods. The aim of this prospective RCT was to determine the role of topical diclofenac in the management of post PRK pain. Sixty-eight adults undergoing bilateral PRK for myopia with or without astigmatism were included. All patients were given 100mg of extended release oral diclofenac at 9pm the evening before surgery and at 9am on the day of surgery. The case group (n=38) were given diclofenac 0.1% drop, one drop 2h preoperatively and one drop four times a day postoperatively for three days. The control group (n=30) were given artificial tears. All patients were examined two days after the procedure. Results showed no significant difference between the reported pain (measured on a scale graded between 0-10) experienced between the case and control groups. Other subjective symptoms, including photophobia and functional activity, were also not different between the two groups. Eyelid oedema and conjunctival injection levels were significantly higher in the control group. The authors conclude that the administration of topical diclofenac in addition to oral diclofenac to treat post PRK pain is unnecessary.

Reference

Effect of topical diclofenac on postoperative photorefractive keratectomy pain: a randomized, controlled trial.
Eslampoor A, Ehsaei A, Abrishami M.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2014;42:810-4.

CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY

Risk factors for NTG in a young Korean population
Reviewed by: Anjali Gupta
Vol 21 No 6
 

Previously known ocular and systemic risk factors for normal tension glaucoma (NTG) include myopia, peripapillary atrophy, disc haemorrhage, migraine, obstructive sleep apnoea, thyroid disease and cerebral infarction. However, most NTG risk factor studies have examined patients aged 40 years and older. The aim of this retrospective, population based, case control study was to assess risk factors for NTG in a young population. Among participants from the Korea National Health and Nutrition Examination Survey 2009-2010, 80 subjects with NTG aged 19-39 years and 4015 controls were included in the study. Variables assessed included diabetes mellitus, hypertension, cholesterol levels, migraine, family history of glaucoma, BMI, cold extremity, fasting plasma glucose, haemoglobin level and refractive error. Results showed that fasting capillary glucose ≥200mmol/L, high myopia (SE≺-6D) and low HDL cholesterol were associated with NTG in a young Korean population.

Reference

Risk factors for open-angle glaucoma with normal baseline intraocular pressure in a young population: the Korea National Health and Nutrition Examination Survey.
Kim MJ, Kim MJ, Kim HS, et al.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2014;42:825-32.

JAMA OPHTHALMOLOGY

Effect of selenium and vitamin E supplements on the development and progression of cataracts
Reviewed by: Lona Jawaheer
Vol 21 No 6
 

The Selenium and Vitamin E Cancer Prevention Trial (SELECT) investigated the influence of dietary supplements on the development of prostate cancer in a group of 35,533 middle aged and older, apparently healthy men. The SELECT Eye Endpoint (SEE) study is an ancillary study involving a subset of 11,267 of the SELECT participants that looked specifically into the impact of selenium (200μg per day from L-selenomethionine) and vitamin E supplements (400IU per day of all rac-α-tocopheryl acetate) on the development of cataract in those patients. Participants with a pre-existing diagnosis of cataract were excluded from analysis in the SEE study. Group participants were randomised into one of four treatment arms: selenium only, vitamin E only, combination of selenium and vitamin E, placebo. The participants were followed up at six monthly intervals and were asked to report new diagnoses of cataract or cataract extraction. Over a mean period of 5.2 years (SD 1.6 years), 185 patients developed cataracts in the selenium group compared to 204 in the no-selenium group (HR, 0.91; 95% CI, 0.75-1.11; p=.37), and 99 patients underwent cataract extraction in the selenium group compared to 120 in the no-selenium group (HR, 0.84; 95% CI, 0.64-1.09; p=.19). In the vitamin E group, 197 patients developed cataracts in the treatment group compared to 112 in the placebo group (HR, 1.02; 95% CI, 0.84-1.25; p=.81), and 114 patients underwent cataract extraction in the treatment group compared to 105 in the placebo group (HR, 1.08; 95% CI, 0.83-1.41; p=.58). The trial was terminated prematurely because of possible adverse effects of the supplements, including a 17% increase in the rate of prostate cancer in the vitamin E group. This is the first randomised control trial (RCT) that has looked at the impact of selenium in isolation on the development of cataract, and it does not provide evidence of any large beneficial effect (although a smaller but potentially important beneficial effect cannot not be ruled out). The lack of impact of vitamin E on cataract development seen in this trial echoes the findings of previous randomised trials.

Reference

Age-related cataract in men in the Selenium and Vitamin E Cancer Prevention Trial Eye Endpoints Study. A randomized clinical trial.
Christen WG, Glynn RJ, Gaziano, M et al.
JAMA OPHTHALMOLOGY
2015;133(1):17-24.

OPHTHALMIC RESEARCH

Results after 1.4mm biaxial cataract surgery and implantation of a new aspheric intraocular lens
Reviewed by: Bheemanagouda Patil
Vol 21 No 6
 

The aim of this study was to analyse the clinical outcome and higher-order aberrations (HOAs) after 1.4mm biaxial micro incision cataract surgery (B-MICS) and implantation of a new aspheric intraocular lens (IOL). A total of 157 eyes of 106 patients were enrolled in this study. The B-MICS (1.4mm, 26 eyes) was followed by an implantation of a micro incision aspheric Incise® IOL MJ14T (Bausch & Lomb, Rochester, NY, USA). The control groups consisted of patients operated with 1.8mm (coaxial MICS, Akreos MI60, 41 eyes), 2.2mm (small incision cataract surgery, Tecnis ZCB00, 44 eyes) and 2.2mm (small incision cataract surgery, CT Asphina, 46 eyes) coaxial phacoemulsification with implantation of an aspheric IOL. Intraoperative and postoperative complications, best-corrected visual acuity, HOAs for a 5.0mm pupil using the iTrace aberrometer and endothelial cell loss were evaluated. In the Incise group, the mean best-corrected visual acuity improved significantly from 0.4±0.27 logMAR preoperatively to 0.05±0.07 postoperatively. The root mean square of total ocular HOAs was measured at 0.419±0.191µm, spherical aberration was measured at 0.168±0.072µm and coma was measured at 0.213±0.200µm. The best-corrected visual acuity (p=0.097), total ocular HOA (p=0.630) and coma (p=0.193) showed no statistically significant difference between the four groups. The aspheric micro incision IOL was safely implanted through a 1.4mm incision and showed similarly good postoperative outcome in comparison to 1.8 and 2.2mm coaxial phacoemulsification.

Reference

Clinical results and higher-order aberrations after 1.4-mm biaxial cataract surgery and implantation of a new aspheric intraocular lens.
Von Sonnleithner C, Bergholz R, Gonnermann J, et al.
OPHTHALMIC RESEARCH
2015;53(1):8-14.

EYE

Ranibizumab for the treatment of age-related macular degeneration
Reviewed by: Nana Theodorou
Vol 21 No 6
 

This multicentre randomised prospective open label study compared 0.5 versus 2mg of ranibizumab in patients with submacular retinal pigment epithelial (RPE) detachment due to age-related macular degeneration. Four treatment regimens were used for the two strengths either monthly for 12 months or monthly for four months followed by repeat ranibizumab injections (RI) on a pro-re nata basis. Thirty patients participated with 36 eligible eyes. Outcome measures were best corrected standardised visual acuities, central 1mm thickness, subretinal fluid and cystoid macular oedema. Both groups showed reductions of the central 1mm thickness with vision improvement seen earlier for those receiving the higher dose. Cataract progression was similar in both groups but RPE tears developed most often in the 2.0mg dose. The authors conclude that although the visual and anatomical outcomes (weeks four and eight) were similar at the end of the study, the higher dose showed more rapid reductions and complete resolution of pigment epithelial detachment (PED).

Reference

Earlier therapeutic effects associated with high dose (2.0 mg) Ranibizumab for treatment of vascularized pigment epithelial detachments in age-related macular degeneration.
Chan C, Abraham P, Sarraf D, et al.
EYE
2015:29:80-7.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Adolescent optic disc haemorrhages
Reviewed by: Fiona Rowe
Vol 21 No 6
 

The authors conducted this study to describe the clinical characteristics of multi-layered optic disc haemorrhages in adolescents. This was a retrospective review of 16 eyes (11 right and five left) of 16 patients with a mean age of 15 ±2.6 years. The main presenting symptoms were acute floaters or blurring. There were no precipitating causes or history. All were myopic. The average retinoscopy was -4.64 ±1.88D. Vitreous haemorrhages were noted in all eyes. Two eyes had subtle bleeding before the disc, five eyes with blood clots in the inferior prepapillary subhyaloid space and nine eyes with blood extending to the premacular area. Peripapillary subretinal haemorrhages and superficial flame haemorrhages were noted. Fifteen discs were crowded and tilted with small or absent cups. This was also the case for the fellow eyes. All haemorrhages resolved without aggressive treatment after one to three months. Multi-layered haemorrhages are relatively uncommon and most commonly affect myopic eyes with crowded and tiled discs. Visual outcome is usually excellent.

Reference

Multi-layered optic disc haemorrhages in adolescents.
Hwang JF, Liu C-J.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51(5):313-8.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Childhood canalicular lacerations
Reviewed by: Fiona Rowe
Vol 21 No 6
 

This retrospective study over 10 years provides data on canalicular lacerations in patients younger than 18 years of age. Of 137 lacerations, 38 (27.7%) met the inclusion criteria. 68.4% were white and 73.7% were male. The mean age was 10.8 years (1.1-17.9). Lacerations were due to dog bites (39.5%), other accidents such as fingers in eyes (21.1%), sports related (18.4%), falls (13.2%) and altercations (7.9%). Lacerations involved the lower lid in 65.8%. All due to dog bites were given IV antibiotics. Isolated lacerations occurred in 36.8%. It showed 13.1% had additional mild self-limiting injuries such as subconjunctival haemorrhage and 5.3% had concomitant orbital fractures. It showed 92.1% of repairs were undertaken in theatre under general anaesthetic and usually within one day of injury. The overall success rate, based on reported complete lack of epiphora, was 89.5%. 31.6% were bothered by eyelid appearance. The authors note that the cause of injuries in children differ to those in adults. These lacerations require monitoring and treatment.

Reference

Pediatric canalicular lacerations: epidemiology and variables affecting repair success.
Murchison AP, Bilyk JR.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:242-8.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Children’s clinic perceptions
Reviewed by: Fiona Rowe
Vol 21 No 6
 

The authors designed a questionnaire intended to be child friendly and for use in a paediatric ophthalmology clinic. The aim of the study was to sample the opinions of the children attending their clinics. Topics in the questionnaire included timing and duration of visits, transport to hospital, what children liked and disliked at visits. They included multiple choice questions with free text space for additional comments. Verbal consent was obtained. Ninety-three children aged 2-16 completed the questionnaire (with and without parent assistance). Transport options included walking to hospital and travel by car, bus and train. Children indicated they saw an average 2.1 professionals per visit which was an under-report. The average duration of visit was 69 minutes (20-215). Sixty-seven percent felt there were sufficient toys and books available. Children reported the most difficult tests as visual acuity, retinoscopy, fundoscopy and binocular vision (in order). They reported the most fun tests as visual acuity, binocular vision, retinoscopy and fundoscopy (in order). Pain from eye drops was scored at an average of 4.2 (0 no pain, 10 most pain). Overall clinic experience was rated on average as 2.5 (0 poor, 10 best). The authors conclude there is room for improvement with explanation, sign-posting and education with regard to clinic visits.

Reference

A survey of children’s’ reported experience in out-patient pediatric ophthalmology clinics.
Tan NET, Lim WS, Jain S.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51(5):270-3.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Masked bilateral SO palsy
Reviewed by: Fiona Rowe
Vol 21 No 6
 

This study examined the occurrence of masked bilateral superior oblique (SO) palsy with contralateral inferior oblique (IO) over action requiring further surgical intervention in children undergoing unilateral IO weakening surgery for presumed unilateral SO palsy. This retrospective study included 50 children with a mean age of 5.6 years. All had unilateral IO surgery. The mean follow-up period was 40 months. Nine (18%) developed masked bilateral SO palsy postoperatively causing reversal of initial hypertropia and requiring IO weakening of the unoperated eye. The preoperative primary hypertropia was significantly smaller for masked than unilateral SO palsy. A preoperative primary hypertropia of <5PD was associated with an odds ratio of 8.2 for requiring reoperation. This can be considered a risk for masked palsy.

Reference

Masked bilateral superior oblique palsy in children.
Dotan G, Roarty JD, Baker HD.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51(6):333-6

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

OCT use with macular retinoblastoma
Reviewed by: Fiona Rowe
Vol 21 No 6
 

The authors explore the use of portable hand-held spectral domain OCT (SD-OCT) in three eyes of three infants and young children with macular retinoblastoma. All were treated with chemotherapy and all had SD-OCT before and after treatment. The children were aged seven, nine and 33 months. In each case the tumour was exophytic with shallow subretinal fluid. No subretinal or vitreous seeding was noted. The foveaola was involved in one case. Mean tumour thickness by ultrasound was 4.8mm (four to six) and mean tumour base was 10.3mm (eight to twelve). Before treatment, the tumours showed smooth (two) or slightly irregular (one) surface topography and low to intermediate optical density by OCT. The normal anatomically intact retina appeared draped over the tumour in each case. After chemotherapy, tumour regression occurred in all cases. At one month, mean tumour thickness was 2.6mm (2.2-3) and tumour base was 6.8 (6-8). By OCT, tumour surface was smooth (one) and irregular (two). Subretinal fluid had almost resolved in all cases. At the tumour site, the retina showed full thickness disorganisation but with abrupt transition to normal retina in all cases. OCT was useful for anatomic monitoring of the macular area.

Reference

Hand-held spectral-domain optical coherence tomography of small macular retinoblastoma in infants before and after chemotherapy.
Cao C, Markovitz M, Ferenczy S, Shields CL.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:230-4.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Results of surgery in a case of FMNS
Reviewed by: Fiona Rowe
Vol 21 No 6
 

The authors present the effects of the tenotomy and reattachment procedure on a patient with accommodative strabismus and fusion maldevelopment nystagmus syndrome (FMNS) who did not require strabismus correction. The ocular motility study of this patient allowed the opportunity to assess the isolated effects of pure 4-muscle T&R procedure on FMNS waveforms and to compare the resulting improvement to those predicted by both model simulation and INS-based analysis. Data and model predicted results concurred. T&R produced improvement in FMNS waveforms similar to those in INS across a broader field of gaze and reduced the Alexander’s law variation. Nystagmus acuity function (NAFX) plots after surgery versus gaze angle were higher and had lower slopes than preoperatively. Parents reported considerable improvement in functional abilities.

Reference

Fusion maldevelopment (latent/manifest latent) nystagmus syndrome: effects of 4-muscle tenotomy and reattachment.
Dell’Osso LF, Orge FH, Jacobs JB, Wang ZI.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:180-8.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Slanted MR surgery for convergence excess ET
Reviewed by: Fiona Rowe
Vol 21 No 6
 

The authors aimed to evaluate the surgical outcomes of bilateral slanted recessions of the medial rectus (MR) muscles in patients with convergence excess esotropia (ET). This retrospective study included 16 patients with a mean age at surgery of 5.6 ±3.05 years. A minimum follow-up was four months. An angle of deviation less than 10PD was achieved in 14 children (88%) for distance and in nine (56%) for near fixation. Mean preoperative near-distance disparity of 20.3 ±6.5PD reduced to 4.37 ±5.6PD postoperatively. In two patients a distance disparity of 16PD persisted requiring treatment with bifocals. Bilateral slanted surgery involved recessing the lower muscle margins by 1-2mm more than the upper margins.

Reference

Slanted medial rectus recession is effective in the treatment of convergence excess esotropia.
Bayramler H, Unlu C, Dag Y.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51(6):337-40.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Strabismus surgical outcome with unilateral visual loss
Reviewed by: Fiona Rowe
Vol 21 No 6
 

The purpose of this study was to analyse the surgical outcome of strabismus surgery in patients with unilateral visual loss and horizontal strabismus. This was a retrospective review of 21 patients. Nine children were reviewed with a mean age of 10.2 ±1.7 years and 12 adults with a mean age of 41.9 ±4.8 years. Mean preoperative logMAR visual acuity in the deviating eye was 1.4 ±0.7. Mean follow-up was 20 months. The most common cause of visual loss was amblyopia followed by congenital cataract. Thirty-eight percent were esotropic and 62% exotropic. All underwent unilateral strabismus surgery with a successful outcome in 89% of children and 75% of adults.

Reference

Surgical outcome of strabismus surgery in patients with unilateral visual loss and horizontal strabismus.
Dotan G, Nelson LB, Mezad-Koursh D, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51(5):294-8.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Superior oblique muscle tuck
Reviewed by: Fiona Rowe
Vol 21 No 6
 

The authors investigate the efficacy and safety of isolated superior oblique tucking in patients with congenital superior oblique palsy. The study includes 21 cases: eight females and 13 males aged 2-34 years. All had obvious superior oblique under action and ipsilateral inferior oblique over action. The hyper deviation in primary position ranged from 6-18 prism dioptres: mean 10.9±3.3 preoperatively. Postoperatively, the mean deviation was 1.5 prism dioptres ±2.6 (2-6). In the reading position, the mean hyper deviation preoperatively was 15.6 prism dioptres ±3.6 (12-22) reducing postoperatively to 2.6 prism dioptres ±3.1 (0-10). The amount of superior oblique tuck ranged from 5-12mm, mean 8.3±2.3. There was no correlation between the surgical amount and corrected vertical deviation in the primary position and reading position, or with the preoperative deviation. The average corrected objective extorsion was 9.5 degrees ±3.3 in 14 patients and also not related to the amount of superior oblique tucking. The abnormal head posture resolved or was less than five degrees in all patients postoperatively. Three patients had a small reversal of their hyper deviation in primary position postoperatively. No patient complained of vertical diplopia in the reading position. All 21 patients had a -1 to -1.5 scale of limitation in elevation in adduction – iatrogenic Brown’s syndrome – but all asymptomatic. The authors proposed that isolated superior oblique tuck could correct hyper deviation of 10 prism dioptres on average and 15 prism dioptres maximum in reading position with correction of objective extorsion by approximately 9.5 degrees on average. For this surgery they recommend that patients have vertical deviations less than 15 prism dioptres in primary position, obvious superior oblique under action (Knapp type 2), ocular extorsion and superior oblique tendon laxity proven by forced duction test. The latter test was considered essential for planning surgery.

Reference

Superior oblique tucking for treatment of superior oblique palsy.
Li Y, Zhao K.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:249-54.

OCCULAR IMMUNOLOGY AND INFLAMMATION

Three years of experience with quantiferon-TB Gold Testing in patients with uveitis
Reviewed by: Nikolaos D Georgakarakos
Vol 21 No 6
 

Quantiferon-TB Gold is a new alternative to the tuberculin skin test that utilises synthetic peptides representing M. tuberculosis antigens ESAT-6, CFP-10, TB7.7 and upon incubation with whole blood IFN-γ is released from pre-sensitised T cells and can be measured by ELISA. This is a retrospective review and database search of the results of quantiferon – TB testing (QFT) on uveitis patients over a period of three years. This included all 343 patients tested for TB with QFT. For blood collection the authors used specialised blood collection tubes provided with the QFT intube test including a nil control tube an M. tuberculosis complex antigen tube and a mitogen tube the latter serving as a positive control. Of the 343 tested patients overall 80 (23.3 %) were positive and 253 (73.8%) negative (and non-conclusive for 10 patients). In 43 out of the 80 QFT+ patients the authors presumed a diagnosis of TB due to other clinical patterns such as radiologic findings, systemic diseases, exposure of a TB patient in the past or urinary tract TB. In the remaining 37 QFT+ patients another associated disease explaining their uveitis was detected (33 with sarcoidosis, one each with Behcet’s, toxoplasmosis, spondyloarthropathy, multifocal chorioretinitis and panuveitis). QFT was positive in nearly a fourth of the uveitis patients especially in the subgroup of intermediate, posterior and panuveitis. Anatomic localisation of the patients who tested positive were distributed as anterior n=12 (15%), intermediate n=22 (27.5%), posterior n=26 (32.5%) and panuveitis n=18 (22.5%). Of the 43 QFT+ patients, 16 were treated with full therapy following World Health Organisation (WHO) recommendations. QFT is a helpful tool in diagnosing uveitis but gives surprisingly high numbers of positives in
uveitis patients not sufficiently explained by immigrant status of the patients. This raises questions regarding treatment implications.

Reference

Three years of experience with quantiferon-TB Gold Testing in patients with uveitis.
Jakob E, Zimmerman S, Dalpe AH, et al.
OCCULAR IMMUNOLOGY AND INFLAMMATION
2014;22(6):478-84.

OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY

A new technique for correction of medial ectropion with a lax medial canthal tendon
Reviewed by: James Hsuan
Vol 21 No 6
 

This is a prospective study of a new technique for repair of medial ectropion associated with medial canthal tendon (MCT) laxity. The procedure was performed on 79 eyes and involved excision of an ellipse of tissue from below the punctum including part of the caruncle medially, tarsal plate laterally and lower lid retractors inferiorly. The defect created was then closed with a circular purse-string type suture drawing the tarsus towards the caruncle and elevating the retractors. The authors make the point that extending the incision to include the caruncle exposes the posterior limb of the medial canthal tendon, and suturing the tarsus to this corrected the laxity and maintained the normal alignment of the lid to the globe. It is not clear why the purse string suture needs to be passed through the skin and tied over a bolster, as this implies the retractors have not been sufficiently advanced and an extra inward rotation of the lid margin is needed. Also a simultaneous lateral canthal tightening / repositioning procedure was required in 52 eyes which had significant residual lid laxity after the medial purse string was placed. These may both reflect the theoretical problem with the purse string suture which inevitably bunches up the tissue rather than reapposing the retractors to the tarsal plate in a vertical plane and the tarsus to the MCT in a horizontal plane. Despite this there are good results from this procedure, with 78% of those with epiphora having complete resolution of tearing. Medial ectropion associated with significant MCT laxity remains a surgical challenge, but this new technique deserves consideration based on the good outcomes reported.

Reference

Caruncular fixation in medial canthal tendon repair: the minimally invasive purse string suture for tendonous laxity and medial ectropion.
Czyz CN, Wulc AE, Ryu CL, et al.
OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY
2015;31:34-7

OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY

Better outcomes from early repair of Type B blow-out fractures
Reviewed by: James Hsuan
Vol 21 No 6
 

This paper examines whether early, rather than late, surgical repair results in better motility outcomes for a particular subgroup of orbital floor blowout fractures. The authors divide floor fractures into Types A and B, depending on whether or not the degree of soft tissue involvement is in proportion to the level of bone fragment displacement. They found in an earlier study that those that had soft tissue displacement out of proportion to the bone disruption, which they labelled Type B, were at greater risk of final reduced motility. They attributed this to constriction of the soft tissue and ongoing ischaemic injury until the fracture is repaired. This paper develops this hypothesis to see if early surgery can improve the final motility in Type B fractures. Twenty-five patients were included and it was found that those that had surgery within seven days had better final motility with larger fields of binocular single vision than those who were operated on later. It has long been appreciated that urgent surgery is indicated for trapdoor orbital floor fractures in children who may have oculo-vagal signs and ischaemia of prolapsed tissue. This paper expands on this theme to include all age groups, and emphasises the importance of recognising on the CT scan when the degree of soft tissue involvement is out of proportion to the bone fragment displacement. The authors have shown that early intervention in these patients will result in better long-term ocular motility. There may be some difficulty in deciding whether a particular fracture is Type A or B, and the study is let down by containing a mixture of prospective and retrospective data. There is no mention of how the timing of surgery was decided, which may be a source of bias. Despite these drawbacks, the paper makes a convincing argument with statistically significant results despite relatively small numbers.

Reference

Surgical timing and postoperative ocular motility in type B orbital blowout fractures.
Liao JC, Elmalem VI, Wells TS, Harris GJ.
OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY
2015;31:29-33.

OPHTHALMIC RESEARCH

Aqueous humour cytokine levels in PCV and nAMD
Reviewed by: Bheemanagouda Patil
Vol 21 No 6
 

This study looks into the possible roles of various cytokines or growth factors in the pathogenesis of exudative age-related macular degeneration (AMD) by comparing aqueous levels of 14 cytokines between eyes with polypoidal choroidal vasculopathy (PCV) and those with neovascular AMD. Forty eyes from 40 patients with treatment-naïve exudative AMD (neovascular AMD=18 and PCV=22) were studied. Twenty eyes from 20 patients with no retinal pathology who underwent cataract surgery served as controls. Aqueous samples were collected just before intravitreal ranibizumab injection in the study and before cataract surgery in the 20 control eyes. Concentrations of 14 cytokines were determined by chemiluminescence-based ELISA: interleukin (IL)-1α, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, IL-13, IL-15, IL-17, vascular endothelial growth factor (VEGF), monocyte chemoattractant protein 1, interferon-γ-inducible protein (IP)-10 and C-reactive protein (CRP). After adjusting for gender, age and axial length, concentrations of CRP and IP-10 were significantly higher in eyes with neovascular AMD or PCV compared with control eyes (p<0.05), and IP-10 levels were strongly associated with lesion size (p=0.002). None of the 14 cytokines, including VEGF, were significantly different between eyes with neovascular AMD and those with PCV. Aqueous concentrations of CRP and IP-10 were elevated in eyes with PCV or neovascular AMD. IP-10 could be associated with the pathogenesis of neovascular AMD and PCV.

Reference

Aqueous humour cytokine levels in patients with polypoidal choroidal vasculopathy and neovascular age-related macular degeneration.
Sakurada Y, Nakamura Y, Yoneyama S, et al.
OPHTHALMIC RESEARCH
2015;53(1):2-7.

OPHTHALMOLOGICA

Intravitreal ranibizumab for the treatment of myopic CNV
Reviewed by: Sofia Rokerya
Vol 21 No 6
 

The authors conducted a prospective study. Sixty-four patients (65 eyes) attended the 12-month follow-up examination. The mean patient age was 47.8 years. Fifty-five patients (86.0%) were females. All patients had pathologic myopia (a spherical equivalent of more than − 6.0 diopters) with a new onset of predominantly classic choroidal neovascularisation (CNV) in the macular area associated with pathologic myopia (<2 months). By localisation 19% of CNVs were juxtafoveal (n=12) and 81% subfoveal (n=52). The median presenting visual acuity was equivalent to 0.2, and the mean baseline central retinal thickness was 313μm. These were treated with intravitreal ranibizumab 0.5mg. The regime consisted of two fixed loading injections, one at baseline and the second one month later. The indication for a third and further pro re nata (PRN) injections was based on the following reinjection criteria: visual acuity (loss of one line or more), development of new macular haemorrhage on fundus examination, evidence of late leakage on fluorescein angiography) and the presence of any fluid or any increase in macular thickness of >50μm on optical coherence tomography (OCT). The primary outcome was a change in BCVA compared to baseline at six and 12 months. The secondary endpoint was the change in central retinal thickness as per OCT from baseline to six and 12 months as well as safety, neovascularisation activity on FA and the number of ranibizumab injections applied. Compared to the baseline, best corrected visual acuity (BCVA) had improved significantly at all later points in time (p=0.001). The mean baseline BCVA was 0.2 (SD 0.13). At 12 months, it was 0.4 (SD 0.21). The greatest improvement in BCVA was seen within the first three months (p=0.0001). The mean central retinal thickness analysed by OCT showed a reduction from 313μm (SD 82) to 243.5μm (SD 31; p=0.0001). CNV closure rate was 61/65 (94) with 2.3 ±0.9 injections. There was a continuous decrease in mean OCT retinal thickness over time. Throughout the follow-up period, patients received an average number of two injections of ranibizumab. Traditional treatments for myopic CNV comprises of laser photocoagulation, transpupillary thermotherapy (TTT) and photodynamic therapy (PDT). These have been unsatisfactory, associated with structural damage, and have not offered long-term visual acuity benefits. Anti-VEGFS offer a better outcome. Intravitreal ranibizumab was been shown to be a safe and efficacious treatment option in myopic CNV. The study emphasises that visual acuity improvement was swift and could be maintained throughout the treatment study period. However, limitations of this particular study include a short-term follow-up.

Reference

Intravitreal ranibizumab for the treatment of choroidal neovascularizations associated with pathologic myopia: a prospective study.
Pasyechnikova NV, Naumenko VO, Korol AR, et al.
OPHTHALMOLOGICA
2015;233:2-7.

ORBIT

A diagnostic imaging technique for optic pathway tumours
Reviewed by: Konal Saha
Vol 21 No 6
 

The authors discuss the difficult clinical scenario of patients with deteriorating visual function and an optic pathway lesion. The morbidity associated with biopsy means a highly sensitive and specific imaging technique would be of great value. The authors describe the use of combined Ga-68-DOTA-TATE PET and CT to diagnose optic pathway meningiomas. The imaging technique relies on the expression of somatostatin receptors by meningiomas. The imaging technique was used to examine 13 patients with ambiguous, symptomatic optic pathway lesions. The results of the imaging were validated by histopathology in five patients and conventional clinical / radiological examination in the others. The authors conclude that Ga-68-DOTA-TATE PET/CT is a sensitive and specific imaging modality for distinguishing meningiomas (somatostatin receptor expressing) from other tumours.

Reference

Ga-68-DOTA-TATE PET/CT for discrimination of tumours of the optic pathway.
Klingenstein A, Haug AR, Miller C, Hintschich C.
ORBIT
2015:34(1);16-22.

ORBIT

Occult spread of squamous cell carcinoma into the orbit
Reviewed by: Konal Saha
Vol 21 No 6
 

The authors describe two cases that may represent perineural spread of cutaneous squamous cell carcinoma (SCC) into the orbit. Both cases had cutaneous squamous cell carcinomas in the region of the lateral orbital wall (innervated by the zygomatico-temporal nerve) which were excised. The patients presented some time later with masses in the lateral orbit which were biopsied and shown to be squamous cell carcinoma. At the time of presentation with the orbital masses, no skin or bony lesions were noted either clinically or on CT imaging. The authors suggest SCC presenting in the region of the lateral orbital wall may show perineural spread down the zygomaticotemporal nerve into the orbit with the orbital mass presenting sometime after excision of the skin lesion and without any detectable skin recurrence.

Reference

Silent squamous cell carcinoma invading the orbit following the course of the zygomaticotemporal nerve.
De Keizer ROB, de Wolff-Rouendaal D, de Keizer RJW.
ORBIT
2015;34(1):10-5.

RETINA

Hyper reflective foci (HRF) on OCT in diabetic retinopathy
Reviewed by: Saruban Pasu
Vol 21 No 6
 

This study investigated the presence of hyper reflective foci (HRF) in asymptomatic patients affected by type 1 or type 2 diabetes, separately, without clinically significant diabetic macular oedema and visual impairment. In total 71 eyes with non-proliferative diabetic retinopathy were imaged using SD OCT. Thirty-three eyes were from type 1 diabetics and 38 eyes from type 2 diabetics. The presence of HRF was defined as the presence of small focal hyper reflective areas scattered mainly in outer retinal layers but also spreading in all retinal layers observed in at least one SD OCT scan. Exclusion criteria included visual impairment, hard exudates or retinal haemorrhages in the fovea, previous retinal surgery / laser, high refractive error, evidence of macular oedema and signs of any other active retinal disease. Control groups of 15 young subjects and 13 older subjects were included for type 1 and 2 diabetics respectively. On SD OCT examination, intraretinal HRF were present in all patients affected by type 1 and type 2 diabetes as scattered punctiform dots invisible at clinical examination, fundus photography and in red free images. HRF amount was significantly higher in the diabetic patients compared to control groups. Type 1 diabetic patients had significantly less HRF than individuals affected by type 2 diabetes. They found patients with a poor quality glycometabolic control were associated with a larger presence of HRF. In the type 2 diabetic group, there was a significant correlation between HRF amount and the presence of hypertension. Sex, patient age and duration of the disease did not influence significantly the number of HRF within the retinal layers. The authors highlight other studies that reported the presence of HRF in the outer retina layers decreases visual acuity of subjects with diabetic macular oedema. Two theories are suggested as to the relevance of HRF; (1) a morphologic sign of accumulation of intraretinal fluid and lipid extravasation, and consequently precursors of hard exudates, and (2) an accumulation of inflammatory cells. The authors conclude by suggesting HFR may be a useful marker for the diagnosis of diabetic retinopathy in the early stage of the disease and an additional marker for the glycometabolic status of the patients.

Reference

Optical coherence tomographic hyper reflective foci in early stages of diabetic retinopathy.
De Benedetto U, Sacconi R, Pierro L, et al.
RETINA
2015;35(3):449-53.

RETINA

VEGF and axial length (RVU)
Reviewed by: Saruban Pasu
Vol 21 No 6
 

The authors of this paper set out to examine whether the concentrations of VEGF in the vitreous were associated with refractive error and axial length in eyes without retinal disease, except of macular holes or epiretinal membranes. A vitreous sample was obtained during 23-gauge pars plana vitrectomy on 34 patients (21 macular holes, 13 epiretinal membranes). Mean age was 62.4, mean IOP was 13.8, mean spherical equivalent was -3.26 +/- 4.23 dioptres (range, -17.50 to 1.50D) and mean axial length was 24.1 +/-1.8mm (range, 21.0 – 29.1mm). The intravitreal VEGF concentration was significantly lower than the VEGF concentration in the blood. Intravitreal VEGF concentrations were not significantly associated with gender or age. A higher intravitreal VEGF concentration was significantly associated with a shorter axial length and a higher hyperopic refractive error. Plasma concentrations of VEGF were not significantly associated with axial length or refractive error. These results are consistent with other studies showing that aqueous humour concentrations of VEGF were significantly and negatively correlated with axial length. The results of this study fit with the observations made in population-based and hospital-based studies that myopia is associated with the lower prevalence of exudative age-related macular degeneration, proliferative diabetic retinopathy, and branch retinal vein occlusion. VEGF may be more diluted in the larger vitreous cavity of eyes with a longer axial length than in the smaller vitreous cavity of eyes with a shorter axial length.

Reference

Intravitreal vascular endothelial growth factor concentration and axial length.
Hu Q, Liu G, Deng Q, et al.
RETINA
2015;35(3):435-9.

SEMINARS IN OPHTHALMOLOGY

Intravitreal injection related endophthalmitis
Reviewed by: Jayavani Myneni
Vol 21 No 6
 

This article reviews the incidence, clinical findings, risk factors, management and visual outcomes in intravitreal injection related endophthalmitis. Incidence of this complication is reported to be in the range of 0.038% to 0.065% (1 in 2000-3000 injections). Patients present typically within five days with reduced vision, pain and photophobia. Data shows a positive culture rate of 52-59.6% with the commonly isolated organism being coagulase negative staphylococcus. Rate of streptococcus isolation is higher (25% to 30%) in contrast to cataract surgery related endophthalmitis where it is 8.2-9%. This has been attributed to passage of respiratory tract flora during the injection procedure. The management of these patients by most practitioners was based on the general guidelines from Endophthalmitis Vitrectomy study. Most cases can be managed with vitreous tap and intravitreal antibiotics. Visual recovery was measured as percentage of patients recovering their pre-injection visual acuity. This outcome was dependent in part on the causative organism. Poorer outcomes were found in cases where streptococcus was isolated. One of the studies suggest that contamination of the injection site with upper respiratory flora such as streptococcus occurs when the patient, nurse or physician talk or cough during the procedure. The authors recommend that this be avoided. But there is no definitively proven benefit with the use of facemask. The use of perioperative antibiotic drops is not supported by enough data and the suggestion is that their widespread use may breed resistance in organisms. However, povidone iodine is consistently found to be effective. Bimanual assisted lid retraction is reported to increase patient comfort when compared to lid speculum without increasing any risk from lash contamination. Investigations of endophthalmitis reported after bevacizumab injections revealed that contamination occurred during the preparation of syringes at compounding pharmacies. This review article is a good summary of the current evidence and practices in management of intravitreal injection related endophthalmitis.

Reference

Endophthalmitis after intravitreal injections of anti-vascular endothelial growth factor medications.
Haddock L, Ramsey DJ, Young LH.
SEMINARS IN OPHTHALMOLOGY
2014;29(5-6):257-62.

THE NEW ENGLAND JOURNAL OF MEDICINE

Aflibercept, bevacizumab or ranibizumab for diabetic macular oedema
Reviewed by: Jonathan C P Roos
Vol 21 No 6
 

Reference

CURRENT EYE RESEARCH

Conjunctival inflammation in glaucoma patients
Reviewed by: Khadijah Basheer
Vol 21 No 6
 

Numerous studies have demonstrated that topical medications and preservatives used for the management of glaucoma can induce significant histopathologic and inflammatory changes in the ocular surface. This study describes an increased expression of major histocompatibility complex class II antigen HLA-DR, used as a marker of inflammation, on conjunctival epithelial cells in patients treated with multiple BAK-preserved topical glaucoma medications, confirming the presence of conjunctival inflammation. This increase in HLA-DR expression correlated with an increase in extracellular metalloproteinase inducer (EMMPRIN) membrane expression. EMMPRIN has been shown to stimulate the production of several matrix metalloproteinases (MMP) in pathological situations such as corneal ulcers and dry eye. This study suggests an MMP mediated modification of the conjunctival extracellular matrix remodelling in glaucoma patients using multiple eye drops with BAK preservative. This is not only important in the symptoms patients experience, which can affect compliance but also has an impact on future management with glaucoma filtration surgery as conjunctival wound healing is a major determinant for its success.

Reference

Increased extracellular matrix metalloproteinase inducer (EMMPRIN) expression in the conjunctival epithelium exposed to antiglaucoma treatments.
Labbe A, Gabison E, Brignole-Badouin F, et al.
CURRENT EYE RESEARCH
2015;40(1):40-7.

EYE

Nonarteritic anterior ischaemic optic neuropathy
Reviewed by: Nana Theodorou
Vol 21 No 6
 

This review article describes nonarteritic anterior ischaemic optic neuropathy (NAION). This condition is one of the common causes of visual loss in adults. The article uses a good range of references and is divided under the headings of; demographics, clinical presentation, pathophysiology, pathogenesis, risk factors, cellular mechanisms, clinical course, differential diagnosis, diagnostic testing, therapy and prevention. NAION typically presents in patients over 50 years as acute painless unilateral visual loss associated with an inferior visual field defect, swollen optic disc and flame-shaped peripapillary retinal haemorrhages. Visual acuity tends to be better than 6/60 likely due to impaired blood flow in the optic nerve vasculature. Patients tend to have at least one underlying vascular risk factor such as nocturnal systemic hypotension, systemic hypertension or diabetes. The risk factor section is of particular interest and well referenced. NAION remains stable over time with some reported cases of spontaneous improvement. The role of differential diagnosis is highlighted and complemented by diagnostic testing. Although there is no consistent treatment for this condition the authors offer a detailed insight into published work and list the limitations of the current literature. Overall this article offers an excellent review of NAION.

Reference

Current concepts in the diagnosis, pathogenesis and management of nonarteritic anterior ischaemic optic neuropathy.
Miller N, Arnold A.
EYE
2015:29:65-79.

INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE

Brn3b neuroprotective effect in rat glaucoma model
Reviewed by: Wai Siene N
Vol 21 No 6
 

An adeno-associated virus-directed overexpression of the Brn3b protein in hypothesised to confer neuroprotective effects in this paper. This is ultimately tested in a well-accepted rat glaucoma model (Morrison’s model: saline injection into episcleral veins of rat eyes with a force sufficient to blanch the aqueous plexus with subsequent scarring of the trabecular meshwork). Viral transduction was firstly demonstrated by increased levels of Brn3b in primary retinal ganglion cell cultures, retinal explants and in the retina and optic nerve head of the rats with induced glaucoma. Neuroprotective effects in the experimental rat glaucoma model was indicated by increased survival of retinal ganglion cell counts and optomotor testing to represent visual function. Furthermore, the group demonstrated modest increased levels of GAP-43; a regulator of axon outgrowth, suggestive of increased neuronal plasticity. This was further supported by the suggestion of restoration of axonal transport which is usually disrupted in IOP-elevated rats eyes; shown by the presence of Alexa conjugated cholera toxin B (an anterograde transport tracer dye). Overall, this is a comprehensive well thought out paper with good promise for clinical translation.

Reference

Neuroprotective effect of transcription factor Brn3b in an ocular hypertension rat model of glaucoma.
Stankowska DL, Minton AZ, Rutledge MA, et al.
INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE
2015;56(2):893-907.

INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE

Implantation of intraocular pressure sensor in glaucoma patients
Reviewed by: Wai Siene Ng
Vol 21 No 6
 

The authors report safety and accuracy of an intraocular intraocular pressure (IOP) sensor placed in the ciliary sulcus during planned cataract surgery. Six patients underwent implantation of the device; a silicone rubber ring-shaped device encapsulating pressure sensitive capacitors and a microcoil antenna. To determine IOP the difference between the absolute pressure sensor in the eye and outside the eye measured by a reader unit held in front of the eye, is calculated. They report a well-tolerated device but rightfully highlight an area of grave concern whereby four out of six patients developed early postoperative sterile anterior chamber inflammation, with two displaying hypopyons. Furthermore, significant pigment dispersion was noted in 50% of patients and all patients showed pupillary distortion. With regards to accuracy, four patients with unexplained IOP shifts, which have been put down to malfunction or a pressure effect on the device during the healing process. The authors should indeed be given credit for their attempt at searching for a continuous IOP monitoring and self non-contact tonometry device. However, with the aforementioned safety issues, size of device necessitating a large corneal incision of about 5.5mm and inexplicable IOP shifts, it would be wise for the group to continue working on refining the sensor shape, size, accuracy and perhaps an alternate site for implantation so as not to impinge onto the uvea, i.e. capsular bag rim or as an IOL piggy back. Otherwise, the risks of an intraocular IOP device far outweighs that of an extraocular one.

Reference

Implantation of a novel telemetric intraocular pressure sensor in patients with glaucoma (ARGOS Study): 1-Year results.
Koutsonas A, Walter P, Roessler G, Plange N.
INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE
2015;56:1063-9.

JAMA OPHTHALMOLOGY

SLT vs. topical treatment with prostaglandin analogues in the management of PACG
Reviewed by: Lona Jawaheer
Vol 21 No 6
 

Selective laser trabeculoplasty (SLT) has been shown to be useful in the management of primary open angle glaucoma (POAG), but its use in primary angle closure (PAC) / primary angle closure glaucoma (PACG) has yet to be validated. Narayanaswamy et al. present the results of a randomised controlled study involving 100 patients with PAC / PACG having previously undergone laser peripheral iridotomies with subsequent opening of at least 180º of the angles. Fifty participants were randomly allocated to treatment with a topical prostaglandin analogue (PGA) and 50 to treatment with SLT in order to address baseline intraocular pressures (IOP) above 21mmHg. The results after a six month period of follow-up showed a decrease in IOP of 4.0mmHg with SLT vs. 4.2mmHg with PGA (p=0.78), and a percentage decrease in IOP of 16.9% with SLT vs. 18.5% with PGA (0.52). Following treatment, 60.0% of SLT patients had IOPs lower than 21mmHg without medications, compared to 84.0% of PGA patients (p=0.08). And 28.6% of patients receiving SLT were treated repeatedly, to address a reduction in IOP of less than 20%. Side-effects of SLT included a transient post-treatment IOP spike of greater than 5mmHg in one patient (2%), and a significant decrease of 4.8% in mean endothelial cell count (p=0.01). The authors also note the difficulty in performing 360º SLT (known to have the best IOP-lowering effect) owing to the anatomy in PAC / PACG. Side-effects of treatment with PGA included uveitis and allergic uveitis (4%) leading to interruption of treatment. This study shows that SLT does produce a decrease in IOP in patients with PAC / PACG which is comparable to that obtained with a PGA. Treatment with SLT in PAC / PACG presents the advantage of avoiding a long-term treatment with its associated cost, risk of non-compliance and its side-effects. However, a longer follow-up period is required to ascertain the long-term effects of SLT.

Reference

Efficacy of selective laser trabeculoplasty in primary angle-closure glaucoma. A randomized clinical trial.
Narayanaswamy A, Leung CK, Istiantoro DV, et al.
JAMA OPHTHALMOLOGY
2015;133(2):206-12.

JOURNAL OF GLAUCOMA

Eye drop prescription and usage in glaucoma patients
Reviewed by: Lorraine North
Vol 21 No 6
 

The authors describe a study using a questionnaire to determine how patients use their glaucoma medications to investigate the association between patterns of eye drop prescriptions and medication use. They enrolled 67 Japanese patients who had been prescribed topical anti-glaucoma medications including a prostaglandin bilaterally. Demographic data was collected, as well as number of bottles prescribed monthly and a five item questionnaire was used to evaluate eye drop administration. Their findings show that patients’ routine medication usage was significantly associated with the number of bottles prescribed monthly. The authors suggested that this was reflective for patients who tended to miss the eye when instilling the eye drops probably because of incorrect technique. Their results also showed that men or patients with mild glaucoma were less likely to be aware of local side-effects than women or patients with severe glaucoma. Limitations of the study include small sample size, practice pattern in Japan and the need for further prospective studies with a larger number needed.

Reference

A study of the association between patterns of eye drop prescription and medication usage in glaucoma subjects.
Kawai-Tsuboi N, Kawai M, Minami Y, Yoshida A.
JOURNAL OF GLAUCOMA
2015;24(3):202-6.

JOURNAL OF GLAUCOMA

Full thickness macular hole after YAG PI
Reviewed by: Lorraine North
Vol 21 No 6
 

The authors report a case of macular hole post YAG peripheral iridotomy (PI) of a patient with pre-existing vitreomacular adhesion. Although a relatively safe procedure, some anterior segment complications are well documented such as corneal endothelium damage, rise in IOP, iris bleed and lens damage. The authors report the case of a 64-year-old female who had an adherent leucoma in the right eye with occludable angles confirmed on indentation gonioscopy. Optical coherence tomography (OCT) was normal in the right eye and showed epiretinal membrane with vitreomacular adhesion in the left eye. The patient received prophylactic YAG PIs to both eyes and three days later complained of dimness of vision in the left eye with reduced vision to 6/36. Examination revealed a stage four full thickness hole requiring vitreoretinal surgery and the vision improved to 6/9. The authors describe the small number of previously reported posterior segment complications with only two being macular holes. The authors postulate that macular hole formation is due to the shock waves generated by Nd:YAG laser and that careful planning and counselling should be performed in such cases along with post PI posterior segment checks.

Reference

Unilateral full-thickness macular hole formation following low-energy Nd:YAG peripheral iridotomy.
Sar S, Sinha S, Mitra S.
JOURNAL OF GLAUCOMA
2015;24(3):e14-e15.

JOURNAL OF GLAUCOMA

IOP and reversibility of RPE detachment
Reviewed by: Lorraine North
Vol 21 No 6
 

The authors describe how three patients with retinal pigment epithelium (RPE) detachment showed a reduction or disappearance of an RPE detachment immediately following prone dark room test (PDRT). The authors performed spectralis OCT on 140 angle closure subjects before and after PDRT. Three patients showed a flattening or complete resolution of the RPE detachment with an acute rise and then fall in IOP. The authors describe the occurrence with short-term IOP changes only but further studies are needed to explore the concept and factors influencing such changes.

Reference

Reversibility of retinal pigment epithelium detachment parallel to acute intraocular pressure rise.
Wang YX, Ran J, Yang LH, et al.
JOURNAL OF GLAUCOMA
2015;24(3):e16-e18.

JOURNAL OF GLAUCOMA

Reproducible OCT RNFL map in unilateral glaucoma
Reviewed by: Lorraine North
Vol 21 No 6
 

The aim of the study was to compare the reproducibility of the optical coherence tomography retinal nerve fibre layer (OCT RNFL) thickness map between glaucomatous and fellow normal eyes of unilateral glaucoma patients. The authors carried out a prospective case controlled study enrolling 107 newly diagnosed unilateral glaucoma patients. Only those that had stable controlled IOP were included. The glaucomatous eye had typical optic nerve damage with typical visual field defect. OCT images were taken on the Cirrus HD-OCT. Seventy-nine Asian subjects were eligible of the 107 to be included. The authors concluded that the test-retest variability’s and tolerance limits of the Cirrus HD-OCT RNFL thickness map of the glaucomatous eyes were lower than the normal eyes. The authors suggest that adjusting the tolerance limits on the basis of the baseline RNFL thickness values might help improve the ability to recognise progression. Further prospective studies are needed as this study was carried out on all Asian ethnic group using scans of high image quality exclusively and authors advise that care should be taken when analysing poorer quality scans.

Reference

Reproducibility of spectral-domain optical coherence tomography RNFL map for glaucomatous and fellow normal eyes in unilateral glaucoma.
Suh MH, Yoo BW, Park KH, et al.
JOURNAL OF GLAUCOMA
2015;24(3):238-44.

JOURNAL OF GLAUCOMA

Visual recovery following Ex-Press vs. trab
Reviewed by: Lorraine North
Vol 21 No 6
 

The authors describe a prospective randomised study of 64 POAG subjects with controlled IOPs comparing visual acuity data in patients randomised to either Ex-Press model P50 or trabeculectomy. Visual acuities were recorded at baseline, day one, weeks one and two and month one, three and six postoperatively. Postoperative complications were recorded plus cup disc ratio and mean deviation on Humphrey Visual Fields. Vision loss was categorised as mild, moderate or severe. The results regarding IOP, central corneal thickness (CCT) and endothelial cell count were not included in this paper. All subjects completed three months follow-up and 61 completed six months. In both groups visual acuity was significantly reduced following surgery, however, the authors found no difference in mean visual outcomes between the two surgical groups. They did, however, find a faster visual recovery with the Ex-Press group compared with trabeculectomy. Their results are similar to other studies such as tube vs. trab as when the visual acuity was evaluated as a categorical variable rather than a continuous variable, those in the trab group lost >2 snellens lines at six months. No difference was found in complication rates. The limitations of the study are reported by the authors as they did not compare IOP between procedures and also visual acuity was measured un-refracted with a pinhole. Further investigation is also required to explore the aetiology further.

Reference

Comparison of visual recovery following Ex-press versus trabeculectomy: results of a prospective randomized controlled trial.
Beltran-Agullo L, Trope GE, Jin YP, et al.
JOURNAL OF GLAUCOMA
2015;24(3):181-6.

NEURO-OPHTHALMOLOGY

Abducens nerve palsy following surgical correction of craniosynostosis
Reviewed by: Claire Howard
Vol 21 No 6
 

The authors present two cases of unilateral abducens palsy secondary to a recent trans-sutural distraction osteogenesis (TSuDO) operation for craniosynostosis. The basic principle of the TSuDO procedure is described as dissection and distraction of the prematurely fused sutures. This complication following surgery has been rarely reported. In both cases the ocular motility deficit resolved over a two to four month period following removal of distractor. Possible mechanisms for this occurrence are discussed within the article. The authors suggest that a neuropraxic or stretch injury may have been the cause. They suggest that the two unusual cases they present may represent a combination of events following distraction osteogenesis producing shearing and / or stretching force of the abducens nerve, which reversed after removal of the distraction hardware.

Reference

Abducens nerve palsy following expansion cranioplasty with distraction osteogenesis.
Yoo H, Chung SA, Yoon SH.
NEURO-OPHTHALMOLOGY
2014;38(6):326-30.

NEURO-OPHTHALMOLOGY

Do operative interventions for IIH improve visual function?
Reviewed by: Claire Howard,
Vol 21 No 6
 

The authors of this paper reviewed patient case notes to determine visual outcome following shunt surgery for idiopathic intracranial hypertension (IIH). A retrospective case notes review was conducted for 50 patients who underwent shunt surgery for IIH. Outcome measures included decimal visual acuity and the mean radial degrees (MRD) of the 14e isopter of the Goldman visual field. These values were measured preoperatively and after a mean follow-up period of 1123 days. The mean number of surgical procedures for each patient was 2.8. The mean decimal visual acuity of the worse affected eye improved from 0.75 to 0.84. The MRD score of the worse affected eye improved on average from 25.6 to 35.5 degrees. In summary, shunting can improve visual function in patients with IIH. There is a need for a randomised controlled trial to further investigate operative interventions in IIH. The authors present a sample size calculation for such a trial.

Reference

Visual outcomes from shunting for idiopathic intracranial hypertension.
Hickman SJ, Raoof N, Panesar H, et al.
NEURO-OPHTHALMOLOGY
2014;38(6):310-9.

NEURO-OPHTHALMOLOGY

Rare case reports of benign optic glioma in adults with clinically aggressive nature
Reviewed by: Claire Howard
Vol 21 No 6
 

Primary optic nerve gliomas are most commonly benign and occurring in childhood. Malignant optic gliomas occur in adulthood and follow an aggressive course usually leading to blindness and death within months. This paper describes the clinical and histopathological features of clinically aggressive but histopathologically benign optic nerve gliomas of adulthood (a third category of optic glioma). Three cases of this rarely reported finding were selected for detailed study, including fundus photographs, visual field reports as well as MRI scan results. In all three cases, patients were initially diagnosed with optic nerve inflammation or benign neoplasm. They all went on to develop neuroradiological extension and all had a rapid deterioration of vision in the affected eye. Visual acuity deteriorated to no perception of light over a three to eight week period. The findings from these cases indicate that benign optic nerve gliomas in adults can be misdiagnosed as inflammation, be clinically aggressive and require excision to prevent further intracranial involvement.

Reference

Aggressive low-grade optic nerve glioma in adults.
Bilgin G, Al-Obailan M, Bonelli L, et al.
NEURO-OPHTHALMOLOGY
2014;38(6):297-309.

NEURO-OPHTHALMOLOGY

Surgical success rates in abducens palsy management
Reviewed by: Claire Howard
Vol 21 No 6
 

The aim of the study was to identify factors associated with surgical outcomes in isolated abducens palsy. To achieve this goal the authors reviewed the records of adult patients with abducens palsy who underwent strabismus procedures during a fourteen year period. Outcome measures included motor alignment, extraocular motility and sensory outcome. A successful outcome was defined for the purpose of this study as absence of diplopia without prisms or face turn, vertical deviation ≤2 prism dioptres (PD) and horizontal deviation ≤10PD. There were 81 patients included in the study and 58% achieved a successful outcome. Success rates varied dependent on the aetiology of the abducens palsy and patients with an underlying neoplastic or traumatic aetiology required more than one strabismus surgery procedure more often (compared with microvascular / idiopathic or other central nervous system causes). For complete abducens palsies, patients undergoing Hummelsheim type procedures had a higher success rate than those who underwent a full tendon vertical rectus muscle transposition. Overall, success rates for strabismus procedures are similar in patients across all aetiologies considered. Although this study has limitations with its retrospective design based on historical data, the information collected from a significant number of patients can provide valuable assistance when deciding on surgical invention options for patients with abducens palsy.

Reference

Functional and motor outcomes of strabismus surgery for chronic isolated adult sixth nerve palsy.
Peragallo JH, Bruce BB, Hutchinson AK, et al.
NEURO-OPHTHALMOLOGY
2014;38(6):320-5.

SEMINARS IN OPHTHALMOLOGY

Long scleral tunnel technique to prevent tube exposure of Ahmed glaucoma valve
Reviewed by: Jayavani Myneni
Vol 21 No 6
 

This retrospective study was done to evaluate the efficacy of long scleral tunnel technique and compare it with pericardium patch graft in preventing tube exposure of Ahmed glaucoma valve. Seventy-eight eyes of 73 patients were included. In group 1 patients, three parallel scleral incisions were made at 1.5-2mm, 6-8mm and 10-12mm away from limbus. A long scleral tunnel was prepared as two pockets one behind the other from these incisions. Paracentesis was done through the first scleral incision at the mouth of the tunnel. For group 2, pericardium patch graft was used to cover the tube. The mean age in both groups was comparable. Mean follow-up period in group 1 was 46.7 months and in group 2 was 43.6 months.Tube exposure was reported in one (2.5%) patient in group 1 at 25th month and three (7.9%) patients in group 3 at 21st, 27th and 30th months. The authors mention that the short follow-up period of the study is a limitation and suggest multicentre studies with longer follow-up periods. It is an interesting article highlighting the efficacy of an alternative approach to tube coverage which is very important to prevent endophthalmitis.

Reference

Efficacy of long scleral tunnel technique in preventing Ahmed glaucoma valve tube exposure through conjunctiva.
Kugu S, Erdogan G, Sevim MS, Ozerturk Y.
SEMINARS IN OPHTHALMOLOGY
2015;30(1):1-5.

THE NEW ENGLAND JOURNAL OF MEDICINE

A randomised, controlled trial of oral propranolol in infantile haemangioma
Reviewed by: Jonathan C P Roos
Vol 21 No 6
 

Since its use was first reported in the New England Journal in 2008, propranolol has become the preferred treatment for infantile haemangiomas. However, there is no consensus as to the optimum dose or duration of treatment and there is a paucity of formal trial data. The authors performed an international multi-centre double-blind placebo-controlled randomised trial. Using an ‘adaptive’ design, the efficacy of one or 3mg propranolol/kg body weight for either three or six months was compared. Out of these four possible groups one (the most efficacious) was then compared against placebo. To assess success, standard photos were taken at 24 weeks and submitted to a central panel of independent blinded investigators. Complete resolution or near-resolution at 24 weeks was classed as success whilst use of any other treatment or withdrawal from treatment was classed as failure. This was a large study – 456 infants were randomised – thus making it more than 10x larger than the largest earlier study. The interim analysis found that the highest dose and longest duration of treatment was best, and when this was compared to placebo the results were clear cut in favour of treatment: 60% vs. 4% resolution (p<0.001). Interestingly the length of treatment was important as there was little resolution after only three months treatment with either 1mg or 3mg, whilst 49% achieved resolution after six months treatment even with 1mg/kg strength (p<0.001). There were two main drawbacks with this study design: a) the most common dose used in clinical practice 2mg/kg/day was not tested but rather a higher and lower dose; b) as the design contained a placebo arm it was unethical to include severe haemangiomas and so these were excluded from the study. Though propranolol is an efficacious and safe treatment it can cause bronchospasm, bradycardia (usually within an hour of administration), hypotension and hypoglycaemia (and should therefore be given after a feed). Of the 400 or so patients receiving active treatment however, only one patient had a serious adverse event (bradycardia in the context of enterocolitis) but a single event did not reach statistical significance.

Reference

A randomized, controlled trial of oral propranolol in infantile hemangioma.
Léauté-Labrèze C, Hoeger P, Mazereeuw-Hautier J, et al.
THE NEW ENGLAND JOURNAL OF MEDICINE
2015;372:735-46.

ACTA OPHTHALMOLOGICA

Functional visual field loss using automated static perimetry
Reviewed by: Nana Theodorou
Vol 21 No 5
 

Functional visual field loss is traditionally assessed by kinetic perimetry, typically producing spiralling isopters. This study looked at the spatial distributions of functional field deficits using automated static perimetry. A retrospective review of automated perimetry records was conducted using a database to identify participants diagnosed with functional visual field loss. Thirty-six cases were found meeting the clinical and tangent screen criteria for functional visual field loss. Thirty-three normal eyes and 57 eyes with true lesions, including optic nerve compression, glaucoma, anterior ischaemic optic neuropathy and vigabatrin toxicity, served as controls. Perimetry consisted of high-pass resolution perimetry using vanishing resolution targets at 50 test locations inside 30 degree eccentricity. The results of standard automated perimetry statistics were unable to reliably discriminate organic versus non-organic visual field loss. Subjective evaluation of visual field results showed that functional fields generally could be identified by the presence of severe and irregular contractions and depressions as well as one or more isolated threshold ‘spikes’, that is, isolated locations showing much better than average sensitivity. On repeated examinations functional field loss was variable between examinations. In the absence of kinetic perimetry, functional visual loss can be identified by automated static perimetry. Useful criteria include severe and irregular contractions and depressions, the presence of isolated threshold spikes and poor inter-test correlations.

Reference

Identification of functional visual field loss by automated static perimetry.
Frisen L.
ACTA OPHTHALMOLOGICA
2014;92:805-9.

BRITISH JOURNAL OF OPHTHALMOLOGY

Orbital cellulitis in Scotland: current incidents, aetiology, management and outcomes
Reviewed by: Jonathan Chan
Vol 21 No 5
 

This is a one year prospective study using the Scottish ophthalmic surveillance unit reporting system amongst Scottish ophthalmologists. Only patients residing within Scotland with a new diagnosis of orbital cellulitis between November 2011 and October 2012 were including in this study. The overall total response rate was 66.4%. In total there were 20 reported cases in the study period affecting six females and 14 males. Fifteen of the 20 cases (75%) were in-patients aged less than 15 years (paediatric group) and five cases (25%) occurred in patients over 17 years (adult group). Within the paediatric age-group, six children (40%) were less than five years old, three children (20%) were between five and 10 years old and six children (40%) were 11 to 15 years old. The overall minimum incidence of orbital cellulitis in Scotland was estimated at 1.6 per 100,000 population in children 0 to 15 years and 0.1 per 100,000 in adults. Seven of the 15 children (47%) had a preceding upper respiratory tract infection and sinus involvement was confirmed by CT scan in 13 of the 15 (87%) children. In comparison, no adult had a pre-existing reparatory infection; one adult was immuno compromised due to haematological malignancy and two adults had preceding trauma. One had preceding facial trauma and one had an intraorbital foreign body and endophthalmitis. The pathogens were isolated in 70% of the cases. Streptococci species and emopholus inferenzie were the most frequently isolated pathogens in children and polymicrobial infection was common. In comparison, single organisms were isolated in adults. All patients received intravenous antibiotics on admission, dual therapy with a third generation cephalosporin and Flucloxacillin were the most common empirical therapy in nine cases, followed by triple therapy with addition of metronidazole in four cases. One adult and a child were treated empirically with a co-amoxiclav monotherapy. Five patients received other dual or triple therapy with various antibiotic classes. All patients underwent CT-imaging. Twelve children (80%) and three adults (60%) had an abscess identified on CT-scanning. Within the paediatric group, five (33%) children had orbital abscesses, five (33%) had sub-periosteal abscesses (SPA) and two (13%) had both orbital and SPAs. Three adults had orbital abscesses only. All children with abscesses and two adults with abscesses underwent surgical intervention. One adult with an orbital abscess had no surgery and recovered with orbital antibiotics alone. Of those who were surgically drained, there was variation in the extent of drainage received; external drainage of abscess alone in seven patients (47%), sinus surgery alone in three patients (20%) and combined drainage of abscess and sinus surgery in four patients (27%). All children completely recovered with no serious adverse outcomes. In the adult group, one patient had intracranial spread of infection with cranial surgical input and the patient with preceding intraorbital trauma and ophthalmitis progressed to evisceration. At three months, three adults were discharged. Of the two remaining under care, one had undergone evisceration and the other had leukaemia with diffuse orbital and lacrimal infiltrate. The authors conclude that this is the largest series of orbital cellulitis reported from the UK. Orbital cellulitis occurs more commonly in children than adults; sinusitis is the major preceding factor in children and adults are more likely to have trauma and comorbidities. The current practice in Scotland is to surgically manage all paediatric SPAs and orbital abscesses, even in those less than nine years of age. Streptococcus species are the most common pathogens in children. Influenza appears to be emerging as a frequent pathogen. Respiratory track organisms are less predictable pathogens in adults, depending on preceding trauma and commodities.

Reference

Orbital cellulitis in Scotland: current incidents, aetiology, management and outcomes.
C Murphy, Livingstone I, Foot B, et al.
BRITISH JOURNAL OF OPHTHALMOLOGY
2014;98:1575-8.

CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY

Nasolacrimal duct screening to minimise post cataract endophthalmitis
Reviewed by: Anjali Gupta
Vol 21 No 5
 

This case control study compared the nasolacrimal duct (NLD) patency in a random sample of phacoemulsification cataract surgery patients (control group) versus a consecutive series of patients who developed endophthalmitis post cataract surgery (case group). NLD syringing was performed in both groups of patients. If the NLD was not patent on syringing, then a macro-dacryocystogram (MDCG) was performed. In the control group 11.8% (4/34 eyes) had NLD obstruction on syringing vs. 50% (5/10 eyes) in the endophthalmitis group (P=0.018). The rate of radiologically confirmed NLD obstruction on MDCG was lower at 2.9% in the control group vs. 20% in the endophthalmitis group (P=0.125). The authors conclude that NLD obstruction is a significant risk factor for postoperative endophthalmitis, therefore screening for symptoms and examination of the lacrimal system prior to cataract surgery is recommended.

Reference

Nasolacrimal duct screening to minimize post-cataract surgery endophthalmitis.
Kam JK, Cheng NM, Sarossy M, et al.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2014;42:447-51.

CURRECT EYE RESEARCH

Precision and accuracy of TearLab osmometer
Reviewed by: Khadijah Basheer
Vol 21 No 5
 

Measuring tear osmolarity has been identified as a potential method for objectively diagnosing dry eye. TearLab osmolarity system is an in situ osmometer which may be a promising candidate for clinical use as it is portable and only requires a 20nL sample. However, some studies have obtained conflicting results regarding the accuracy of this system. This study examined the precision and accuracy of the TearLab system using 10 different salt solutions of varying osmolarity compared to a freezing point depression osmometer. Their results showed that the TearLab system can precisely and accurately measure osmolarity of salt solutions, but larger differences were found between the two methods at both extremes of osmolarity. Furthermore, this was an in vitro study and therefore was not influenced by any external factors that have led to the large repeatability coefficients in other studies including the time of measurement, differences in observer techniques and possible change in osmolarity from disrupting the tear film. The authors state that more studies need to be performed, ideally in vivo before TearLab can be considered as clinically useful. Firstly, there is a significant overlap in osmolarity between mild to moderate dry eye patients and normal controls and therefore any osmolarity value for diagnosis may lead to low sensitivity and a high false negative rate. Secondly, patients with dry eye have significant variability that is greater than normal controls and this may reduce the ability of TearLab to monitor disease progression.

Reference

Precision and accuracy of TearLab osmometer in measuring osmolarity of salt solutions.
Yoon D, Gadaria-Rathod N, Oh C, Asbell P.
CURRECT EYE RESEARCH
2014;39(12):1247-50.

EYE

Glaucoma prevalence in sleep apnoea
Reviewed by: Nana Theodorou
Vol 21 No 5
 

Obstructive sleep apnoea (OSA) is a disorder characterised by brief interruptions of breathing during sleep and results from complete or partial collapse of the pharyngeal airway. This study investigated the prevalence and progression of glaucoma in 39 patients receiving treatment for OSA. Participants were over 30 years and had been diagnosed with moderate and severe OSA in the sleep clinic at Hamad General Hospital in Qatar. The severity of OSA was graded as mild, moderate, or severe based using the apnoea hypopnea index. All patients underwent ophthalmological examination including visual field testing, optical coherence tomography and pachymetry. Study patients were followed up in the ophthalmology and sleep clinics for a period of three years at six monthly intervals. Most patients were male with a mean age of 52 years; 27 patients had severe and 12 moderate OSA. Examinations found that eight (20%) of the 39 OSA patients had glaucoma. Six of these patients had normal-tension glaucoma and two had high-tension glaucoma. Among the 27 patients with severe OSA, seven had glaucoma, and among 12 patients with moderate OSA, one had glaucoma. There was a prevalence of glaucoma in the severe OSA group compared with the moderate OSA group without statistical significance (P=0.4). The results of this small scale study confirm previous findings that severe OSA is a risk factor for glaucoma.

Reference

Prevalence of glaucoma in patients with moderate to severe obstructive sleep apnea: ocular and morbidity outcomes in a 3 year follow-up study.
Hasjim SP, Al Mansouri FA, Farouk M, et al.
EYE
2014;28:1304-9.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Ametropic amblyopia and stereopsis
Reviewed by: Fiona Rowe
Vol 21 No 5
 

This study aimed to evaluate the correlations between ametropic amblyopia (hypermetropic – 110, myopic – 30, and astigmatic – 65) and stereopsis in 205 children – mean age of 5.2 years ±1.8. For near stereopsis, significant results were found for mild and moderate amblyopia across myopia, astigmatism and hypermetropic refractive errors. Children with hypermetropia had better central stereopsis and macular stereopsis than those with myopia or astigmatism. Children with astigmatism had a significant reduction in stereopsis versus those with myopia and hypermetropia. Reduced stereopsis was seen in those with severe amblyopia. There was no significance for distance fusion range across groups. The authors conclude that types and degrees of amblyopia are closely related with stereopsis. Those with astigmatism were worst and the authors proposed more attention should be paid to treatment of this form of amblyopia.

Reference

Stereoscopic visual acuity in types of ametropic amblyopia in children.
Li S, Zon H, Wei C.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:105-10.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Childhood headaches
Reviewed by: Fiona Rowe
Vol 21 No 5
 

The goal of this study was to compare headache resolution in children receiving or not receiving refractive correction. The authors conducted a retrospective review of 158 patients: 78 male and 80 female aged three to twelve years (mean eight). Twenty-seven percent had clinically significant refractive errors or had previously been prescribed glasses. It showed 30.4% had ophthalmic history other than refractive error including strabismus, convergence insufficiency, Duane’s retraction syndrome, amblyopia, nasolacrimal duct obstruction, functional visual loss, allergic conjunctivitis, retinopathy of prematurity, nystagmus, optic disc anomaly, anisocoria and ectopic lentis. Eighteen percent had a family history of migraine. Fourteen percent had temporal association of headache with reading, TV, computer use and homework. Nine and a half percent complained of blurred vision or diplopia. A new or altered prescription was given to 21% and prior glasses stopped for 2.5%. Follow-up information was obtained for 110 patients. It showed 76.4% had resolution or significant improvement. Migraine was later diagnosed for five patients. No significant difference in resolution was found for those who received a change in prescription versus those who did not. The authors concluded that most children with headache do not have ophthalmic abnormalities

Reference

Headache and refractive errors in children.
Roth Z, Pandolfo KR, Simon J, Zobal-Ratner J.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:177-9.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Choroidal defects in neurofibromatosis
Reviewed by: Fiona Rowe
Vol 21 No 5
 

The aim of this study was to investigate the frequency of choroidal abnormalities using infrared reflectance imaging with optical coherence tomography (OCT) in paediatric patients with neurofibromatosis (NF) type 1. Thirty-eight eyes of 19 patients were reviewed. NF1 was diagnosed by NIH criteria. Mean age was 8.63 years ±3.15. Hyper-reflective choroidal abnormalities were found in 15 patients (78.9%). A positive correlation was found between the number of choroidal abnormalities of both eyes and patient age. Iris hamartomas (Lisch nodules) were found in nine patients (47.4%). Choroidal abnormalities were present in all patients with Lisch nodules. Conventional fundus examinations and colour fundus photography did not reveal any abnormalities. Choroidal abnormalities were most often observed at the posterior pole. The authors propose infrared reflectance imaging with OCT is a useful aid in the diagnosis of NF1.

Reference

Frequency of choroidal abnormalities in pediatric patients with neurofibromatosis type 1.
Goktas S, Sakarya Y, Ozcimen M, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:204-8.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Postoperative astigmatism
Reviewed by: Fiona Rowe
Vol 21 No 5
 

The authors investigate the short and long-term postoperative refractive effects of medial rectus recession on the involved eye and explain the detectable effects in detail by the results of vector analysis in 52 eyes and 32 patients. The subjects had a mean age of 8.6 years ±7.8. The results showed a significant difference between the preoperative and one month postoperative spherical equivalent values and the one month and one year values. There was a significant difference between the one month and one year postoperative values of cylinder dioptres and significant differences for surgically induced astigmatism, magnitude of error, flattening effect and astigmatism axis. A myopic shift of approximately 0.5D was seen at one month postoperative and a hypermetropic shift of 0.32D seen at one year postoperative. Changes at one month were considered to be associated with alterations in tension applied by the recessed muscle on the cornea. The effect disappeared by one year.

Reference

Surgically induced astigmatism following medial rectus recession: short term and long term outcomes.
Kutluturk I, Eren Z, Koytak A, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:171-6.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Resection versus advancement for consecutive XT
Reviewed by: Fiona Rowe
Vol 21 No 5
 

The authors performed a retrospective review of results for patients treated with resection for consecutive exotropia in comparison to patients treated with advancement to the original insertion. The age of the resection and advancement groups averaged 33.6 and 38.2 years respectively. The mean preoperative angle was 32.3 for the resection group and 36.2 prism dioptres for the advancement group. Postoperative angle was 11.5 in the resection group and 11.4 prism dioptres in the advancement group. Forty-seven percent of the resection group and 63% of the advancement group achieved alignment within 10 prism dioptres of ortho. The results showed no significance between both groups and the authors conclude both surgical methods are useful.

Reference

Treatment of consecutive exotropia: unilateral lateral rectus recession combined with medial rectus advancement or resection.
Mangla D, Simon JW, Mangla N, Zobal-Ratner J.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:116-9.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Results of changed treatment for retinoblastoma
Reviewed by: Fiona Rowe
Vol 21 No 5
 

Systemic chemotherapy was adopted in Kobe in 1996. In this study the authors analyse the clinical manifestations and results of treatment for patients with retinoblastoma since then. This review is of 43 eyes of 34 patients. Those with follow-up to a minimum of one year were included – 25 monocular and nine binocular cases with a median age at first examination of 13 months (22 days to six years and two months). Three patients had a family history of retinoblastoma. The youngest case was one of these three children. The mean observation period was 10.6. months ±53 (16-211). Clinical presentation at first examination included leukocoria (33) and exotropia (one). There was no correlation between age at first examination and classification stage of retinoblastoma. Nineteen eyes were in the initial enucleation group and 24 eyes in the initial preservation plan. Of the latter, 11 eyes continued preservation and 13 discontinued. Of the preservation cases, seven were enucleated because of poor tumour reduction, five showed tumour recurrence, one was enucleated due to secondary glaucoma, one developed secondary cataract and one patient had multi-organ metastases and died. Systemic chemotherapy with vincristine after 2000 had slightly better outcomes than that with ifosfamide before 1999. The study demonstrated that in cases that eventually need enucleation, chemotherapy can significantly delay this with the advantage that the orbit and eyelid can develop normally first and thus reduce the occurrence of facial defects caused by orbit and lid deformities following early enucleation. Eye preservation treatment was performed for a higher proportion of advanced cases among bilateral cases than monocular cases.

Reference

Clinical manifestations and treatment of retinoblastoma in Kobe Children’s Hospital for 16 years.
Okimoto S, Nomura K.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:222-9.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Results of single muscle advancement surgery
Reviewed by: Fiona Rowe
Vol 21 No 5
 

The aim of this study was to determine quantitatively the efficacy of medial and lateral rectus muscle advancement in consecutive exotropia and esotropia. The authors analysed the relationship between the change in muscle position and the change in visual angle deviation. Eleven children with exotropia and esotropia were recruited with a mean age of 7.4 years ±1.9. Secondary surgery was undertaken at 17.7 years ±12.4 for esotropia and 62 years ±24.1 for exotropia. Success was defined as a deviation <10 prism dioptres at one week post-op. The average correction ratio for all cases was 4.31 dioptres per mm. The larger the preoperative angle and amount of rectus advancement, the greater the surgical dose effect. No postoperative duction or version limitations were noted. The results suggest single muscle advancement is sufficient to correct most cases.

Reference

Surgical dose-effect relationship in single muscle advancement in the treatment of consecutive strabismus.
Kim BH, Suh SY, Kim JH, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:93-9.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Review of paediatric infectious endophthalmitis
Reviewed by: Fiona Rowe
Vol 21 No 5
 

This paper presents a review on paediatric infectious endophthalmitis and considers aetiology, prognosis and management. Classification included exogenous and endogenous. Diagnosis was based on presenting history, signs and symptoms, cultures and imaging. Exogenous cases included postoperative endophthalmitis (strabismus surgery, glaucoma surgery, trabeculectomy with antimetabolite use, glaucoma drainage implants, cataract surgery, penetrating keratoplasty, pars plana vitrectomy) and post traumatic endophthalmitis. Management options included intravitreal antibiotics, systemic antibiotics, topical and subconjunctival antibiotics and corticosteroids. The review also considers management of fungal endophthalmitis, visual prognosis and complications. The authors conclude this is a rare condition often associated with very poor outcome. Open globe trauma and glaucoma surgery are the most frequent causes in children. Endogenous infections are least common. Streptococcus and staphylococcus are common bacterial agents in traumatic and surgical cases whereas candida albicans is common in endogenous endophthalmitis.

Reference

Pediatric infectious endophthalmitis: a review.
Khan S, Athwal L, Zarbin M, Bhagat N.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:140-53.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Suture tensile strength
Reviewed by: Fiona Rowe
Vol 21 No 5
 

The effect of solutions commonly used in strabismus surgery were evaluated on 6-0 polyglactin suture tensile strength. The method involved a simple dead load test. Specimens of 6-0 suture were loaded in tension until breakage. This was repeated on 10 samples. The test was then repeated after soaking in solution for 30 minutes in normal saline, 5% povidone-iodine solution and 0.5% chlor solution. There was no significant difference between groups. The authors concluded there was no change in tensile strength of 6-0 polyglactin suture after immersion in various solutions.

Reference

The effect of commonly used surgical solutions on the tensile strength of sutures.
Rompat R, Jain S.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:189-90.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Three muscle surgery results for ET
Reviewed by: Fiona Rowe
Vol 21 No 5
 

There is limited information in the literature on the outcomes of three muscle surgery. The authors aimed to evaluate the medium term motor outcomes of three horizontal muscle surgery in 18 patients with large angle infantile esotropia of at least 55PD. The median age at surgery was 22 months (10-168). Only one child had limited lateral gaze postoperatively. The mean preoperative angle was 68.8 PD ±9.54 which reduced to 1PD (esotropia 30 to exotropia 4). Medial rectus recession was 5-6.5mm and lateral rectus resection was 7-8mm. Results within ≤10PD were achieved in 78% of cases. There was a median follow-up of 32 months (5-63). One patient needed two additional surgeries for vertical deviation. Four patients needed second surgery for residual esotropia. The mean dose / response ratio was 3.32±0.62PD/mm. The authors conclude there is a good rate of success in short and medium term. Overcorrection was not a serious problem but under correction can still occur.

Reference

Medium term outcomes of three horizontal muscle surgery in large angle infantile esotropia.
Bayramlar H, Karadag R, Yildirim A, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:160-4.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Vici syndrome
Reviewed by: Fiona Rowe
Vol 21 No 5
 

Vici syndrome is a condition associated with agenesis of the corpus callosum, congenital cataract, incomplete albinism, ± immunodeficiency and cardiomyopathy. Individuals show profound hypotony and severe neuro abnormalities. This paper reports a case of Vici syndrome. A 38-month-old female had bilateral nuclear and anterior polar cataracts and bilateral optic nerve atrophy. Visual interaction improved after left cataract extraction and anterior vitrectomy. This child was quiet, placid and profoundly hypotonic. She had fair skin and lightly pigmented blond hair, blue irides and normal sclera, long eyelashes, mild bitemporal narrowing, narrow palate and parallel transverse palmar creases bilaterally. VEP demonstrated misrouting of optic nerve pathways. OCT showed a poorly defined fovea with lesser degree of foveal depression. VEP was reported to aid the diagnosis of the case.

Reference

Ophthalmologic features of Vici syndrome.
Filloux FM, Hoffman RO, Viskochil DH, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:214-20.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

William’s syndrome
Reviewed by: Fiona Rowe
Vol 21 No 5
 

William’s syndrome is a congenital multisystem disorder involving the cardiovascular, connective tissue and central nervous systems. The aim of this study was to evaluate the frequency and severity of ophthalmic manifestations and associated diseases as well as provide epidemiology data in patients with this syndrome. This was a longitudinal prospective observation study of 30 patients whose diagnosis was confirmed by fluorescence in situ hybridisation (FISH) test. The study included 15 females and 15 males with an average age of 14.5 years ±1.38. Fifty-seven percent were white, 33% mixed race and 10% black. All presented with a typical face, delayed development and mental retardation, friendly personality and dental and skeletal abnormalities. Fifty percent had glasses before first ophthalmic examination. Seventy-seven percent had refractive error of which hypermetropia was most common in 67%, followed by astigmatism (20%) and myopia (7%). It showed 84% had a best corrected visual acuity of 20/20 with only one case of amblyopia with 20/50 acuity. Also 23% had epicanthus, 10% had stellate patterns of the iris and 36.7% had strabismus (30% esotropia and 6.7% exotropia). Seventy percent had normal ocular motility whilst 27% had oblique muscle over action and 3% had oblique muscle under action. Abnormal binocular vision was found in 43%. Diffuse arterio-venous tortuosity was noted in 27%.

Reference

William’s syndrome: ophthalmological examination and review of systemic manifestations.
Weber SLP, Souza RB, Ribeiro LG, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:209-13.

JOURNAL OF REFRACTIVE SURGERY

Visual performance of new multifocal IOL
Reviewed by: Mrinal Rana
Vol 21 No 5
 

Multifocal IOLs (MIOLs) keep evolving to try and get the best outcome in terms of vision and reduction of side-effects. This prospective interventional study was carried out on 34 eyes of 17 patients (11 women (65%) and six men (35%)) with mean age of 64 years (SD - 12.8; range 42-84 years). All patients were enrolled under strict exclusion criteria making sure that no other ocular pathology was found, which could have an effect on the visual prognosis. They underwent binocular sequential surgery under topical anaesthesia using standard suture less phacoemulsification technique and the new bi-aspheric, segmented, multifocal intraocular lens was inserted. Outcome measures checked were manifest refraction, uncorrected and corrected distance and near visual acuity; defocus curves in photopic conditions; contrast sensitivity; halometry as an objective measurement of glare and patient satisfaction questionnaires. Mean residual refraction was –0.13(±0.51) dioptres (D). Twenty-five eyes (74%) were within the mean spherical equivalent of ±0.50D. Mean uncorrected distance acuity was +0.10±0.12 logMAR monocularly and 0.02±0.09 logMAR binocularly. Thirty-two eyes (94%) could read 0.3 or better without any reading correction and all patients could read 0.3 or better with the near correction. Mean monocular uncorrected near visual acuity was 0.18±0.16 logMAR, improving to 0.15±0.15 logMAR with distance correction. Mean binocular uncorrected near visual acuity was 0.11±0.11 logMAR, improving to 0.09±0.12 logMAR with distance correction. Mean binocular contrast sensitivity was 1.75±0.14 log units at three cycles per degree, 1.88±0.20 log units at six cycles per degree, 1.66±0.19 log units at 12 cycles per degree, and 1.11±0.20 log units at 18 cycles per degree. Mean binocular and monocular halometry showed glare profile of less than 1° of debilitating light scatter. Therefore the M plus MIOL has been found to be an effective method of providing good distance acuity and near vision. Further studies with extended follow-ups were suggested to get to know about the full potential of this premium implant.

Reference

Visual performance of a new bi-aspheric, segmented, asymmetric multifocal IOL.
Berrow EJ, Wolffsohn JS, Bilkhu PS, Dhallu S.
JOURNAL OF REFRACTIVE SURGERY
2014;30(9):584-8.

OPHTHALMOLOGY

Intravitreal dexamethasone implant for diabetic macular oedema
Reviewed by: Brian Ang
Vol 21 No 5
 

The authors report on the three-year outcomes of the Ozurdex Dexamethasone (DEX) intravitreal implant multi-centre trial for the treatment of diabetic macular oedema (DME). Patients with DME (best-corrected vision of 20/50 to 20/200 and central retinal thickness of ≥300µm) were randomised in a 1:1:1 ratio to DEX implant 0.7mg, DEX implant 0.35mg or sham. Exclusion criteria included uncontrolled diabetes, concurrent use of systemic steroid, glaucoma, active neovascularisation, history of intraocular laser or surgery within 90 days, intravitreal anti-VEGF injection within 90 days, and intravitreal triamcinolone injection within 180 days. There were 1048 patients enrolled, but only 607 (57.9%) completed the three year study duration. The average number of treatments was 5.0 in the DEX implant 0.7mg group, 5.2 in the DEX implant 0.35mg group, and 5.1 in the sham group. In terms of visual acuity improvement of >15 letters, this was achieved in 22.2% of the DEX implant 0.7mg group, in 18.4% of the DEX implant 0.35 group, and in 12.0% of the sham group. The average reduction in central retinal thickness was 111.6µm in the DEX 0.7mg group, 107.9µm in the DEX 0.35mg group, and 41.9µm in the sham group. The commonest complications were elevated intraocular pressure (IOP) and cataract. IOP elevation requiring topical medication occurred in 41.5% in the DEX 0.7mg group, 37.6% in the DEX 0.35mg group, and 9.1% in the sham group. Cataract surgery was required in 59.2% of phakic eyes. In comparison to sham, the Ozurdex intravitreal implant show significant visual improvement and reduction in central retinal thickness. The side-effect profile was less in comparison to those previously reported for intravitreal fluocinolone and triamcinolone, but still significant nonetheless. A trial comparing Ozurdex to intravitreal anti-VEGF injections for DME will help to establish whether the benefit of reduced numbers of injections is outweighed by the significant side-effect profile.

Reference

Three-year, randomized, sham-controlled trial of dexamethasone intravitreal implant in patients with diabetic macular oedema.
Boyer DS, Yoon YH, Belfort Jr B, et al.
OPHTHALMOLOGY
2014;121:1904-14.

OPHTHALMOLOGY

Medical management and diabetic retinopathy progression
Reviewed by: Brian Ang
Vol 21 No 5
 

The ACCORD Eye Study was designed to evaluate the benefit of intensive glycaemic control (HbA1c <6.0% vs 7.0-7.9%), intensive systolic blood pressure control (<120mmHg vs. <140mmHg), and combined fenofibrate and simvastatin therapy in the development and progression of diabetic retinopathy. There were 3472 type 2 diabetic patients enrolled, and 2856 returned for examination at four years. The mean age of patients was 62 years, while the average duration of diabetes was 10 years. Blood pressure control did not have any effect on diabetic retinopathy progression. In contrast, intensive glycaemic control and fenofibrate treatment were both shown to reduce diabetic retinopathy progression. Interestingly, fenofibrate showed no benefit in eyes that did not have any diabetic retinopathy to start with. The results of this study have to be balanced in the context of intensive glycaemic treatment being associated with a 22% higher risk of death (5.0% vs. 4.0%) and three times higher risk of hypoglycaemic episodes (10.5% vs. 3.5%) compared with standard glycaemic treatment.

Reference

The effects of medical management on the progression of diabetic retinopathy in persons with type 2 diabetes. The action to control cardiovascular risk in diabetes (ACCORD) eye study.
Chew EY, Davis MD, Danis RP, et al.
OPHTHALMOLOGY
2014;121:2443-51.

OPHTHALMOLOGY

Methotrexate and mycophenolate mofetil for non-infectious uveitis
Reviewed by: Brian Ang
Vol 21 No 5
 

This is the first reported randomised clinical trial comparing methotrexate versus mycophenolate mofetil (MMF) for the treatment of non-infectious intermediate uveitis, posterior uveitis or panuveitis. To be eligible for recruitment, patients had to be on ≥15mg oral prednisone and demonstrated a previous history of steroid taper failure. Additionally, the patients should not have had any previous exposure to immunosuppressants, intraocular surgery in the past 30 days, fluocinolone acetonide implant surgery in the past three years, and periocular or intravitreal corticosteroid injection in the past 90 days. A total of 80 patients were randomised to either 25mg a week oral methotrexate or 1g twice daily oral MMF. If the medication was not tolerated, patients were allowed to adjust their study dose. Sixty-seven patients (35 methotrexate; 32 MMF) completed the six month study period. There were no statistically significant differences in terms of the time to steroid-sparing control of inflammation, change in best-corrected visual acuity, resolution of macular oedema, adverse events, or tolerability. Treatment success was achieved in 69% of methotrexate patients and 47% of MMF patients, but this difference did not achieve statistical significance (P=0.09). The results from this study seem to contrast with that from other retrospective studies, and is likely to have cost implications due to the significantly higher price of MMF.

Reference

A randomized clinical trial comparing methotrexate and mycophenolate mofetil for non-infectious uveitis.
Rathinam SR, Babu M, Thundikandy R, et al.
OPHTHALMOLOGY
2014;121:1863-70.

RETINA

Prognostic information for PRP-naive patients
Reviewed by: Saruban Pasu
Vol 21 No 5
 

The Diabetic Retinopathy Study group demonstrated that pan retinal laser photocoagulation (PRP) reduces severe vision loss by up to 50% in cases of proliferative diabetic retinopathy (PDR). The authors of this current study aimed to provide information for laser naive patients regarding the risk of future vitrectomy based on clinical examination findings. A retrospective review was carried out on 374 eyes principally noting the date of initial PRP and dates / incidence of vitrectomy. Patients were divided into three groups: Group 1 (PDR alone) n=185, Group 2 (PDR  and VH) n=160, Group 3 (PDR with neovascularisation of the iris [NVI], VH and traction, VH and fibrosis, or fibrosis alone) n=29. The percentage of eyes undergoing vitrectomy within one year was 9.73%, 26.9% and 37.9%, respectively. Within two years the percentage of eyes were 15.7%, 34.4% and 48.3%, respectively. Group 2 patients were 2.78 times and Group 3 were 3.54 times more likely than Group 1 patients to undergo vitrectomy within two years. Findings such as VH or fibrosis at initial PRP were found to be statistically significant in influencing the incidence of vitrectomy within two years. Patients not on insulin therapy were 1.74 times more likely to require vitrectomy within two years than those on insulin. This study provides quantitative and statistically significant evidence that diabetic patients with PDR receiving PRP have a 12.2% and 21.1% likelihood of undergoing a vitrectomy within the next one to two years, respectively. Patients who present with PDR with other clinical findings, such as VH, fibrosis, traction, and both VH and traction together, will have a much higher likelihood of requiring a vitrectomy within the next couple of years.

Reference

Ocular findings at initial pan retinal photocoagulation for proliferative diabetic retinopathy predict the need for future pars plana vitrectomy.
Parikh R, Shah R, Vanhouten J, et al.
RETINA
2014;34(10):1997-2002.

RETINA

Timing of vitrectomy for retained lens fragments
Reviewed by: Saruban Pasu
Vol 21 No 5
 

The purpose of this study was to compare the results of same setting vitrectomy with delayed vitrectomy for retained lens fragments following cataract surgery. Same setting vitrectomy was defined as the patient not leaving the operating table following cataract surgery. Significantly delayed surgery was defined as vitrectomy occurring more than 28 days after phacoemulsification. The authors retrospectively looked at 28 eyes (13 same setting, 15 delayed setting). Pre-cataract extraction, there were no significant differences in axial length, IOP, or median BCVA between the two groups. The mean time from cataract extraction to vitrectomy was 26.6 days in the delayed group. More eyes in the delayed group had IOL insertion at the time of cataract surgery, before vitrectomy. There were no differences between the groups in change of BCVA from initial pre-cataract visit to the most recent examination. Although not significant, there was a trend for same setting eyes to achieve good vision faster. More eyes in the delayed group had an IOP greater than 30mmHg at some time point during the postoperative course. Seven eyes were in the significantly delayed group, all of whom showed no significant difference from the same setting group regarding any follow-up outcomes. The authors conclude that although same setting surgery offers no significant acuity advantage over delayed surgery, in patients with advanced glaucoma where an IOP of more than 30 would not be desirable, same setting surgery may be advantageous.

Reference

A comparison of same setting versus delayed vitrectomy in the management of retained lens fragments after cataract surgery.
Orlin A, Parlitsis G, Chiu Y, et al.
RETINA
2014;34:1969-76.

STRABISMUS

Strabismus and binocular summation
Reviewed by: Fiona Rowe
Vol 21 No 5
 

The authors conducted a pilot study to investigate the effect of visual noise or background complexity on binocular summation in patients with strabismus. A target embedded in pixel noise was used. The study involved performance of a task detecting a luminance target measured at 0, 10 and 20udeg2 of visual noise for binocular and monocular conditions. Subjects included 10 with exotropia, 10 with esotropia and 13 controls. Overall, for esotropia and exotropia, a significant decrease in binocular summation was noted compared to controls. For exotropia alone, there was also a significant lower amount of binocular summation. Mean binocular inhibition (summation ratio <1) was at both noise levels. The authors conclude that strabismus can lead to decreased binocular summation and binocular inhibition.

Reference

Effects of visual noise on binocular summation in patients with strabismus without amblyopia.
Pineles SL, Lee PJ, Velez F, Demer J.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:100-4.

STRABISMUS

VDT use and dry eye disease in children
Reviewed by: Fiona Rowe
Vol 21 No 5
 

There has been an increase in the amount of work performed using video display terminals. This study compared school children with and without dry eye disease and evaluated the risk factors of dry eye disease and evaluated the risk factors of dry eye disease associated with video display terminal (VDT) use. Three-hundred-and-two children were included: 14 with nocturnal lagophthalmos, trichiasis or epiblepharon were excluded. Twenty-eight children had dry eye disease – mean age of 11 years ±0.61. Two-hundred-and-sixty children served as controls – mean age of 10.87 years ±0.66. Fifty-one percent used smartphones and all used computers and TVs. The results showed that use of phones, duration of phone use and duration of VDT use increased risk of symptoms. Complaints included visual fatigue, dryness, headaches and burning sensations. The dry eye group had punctuate epithelial erosions. Phone use in the dry eye group was 71% versus 50% in the control group.

Reference

Association between video display terminal use and dry eye disease in school children.
Moon JH, Lee MY, Moon NJ.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:87-92.

ACTA OPHTHALMOLOGICA

Long-term open angle glaucoma cohort study
Reviewed by: Nana Theodorou
Vol 21 No 4
 

This was a study to estimate the development of open angle glaucoma (OAG) in a screened and re-examined elderly group as compared to an unscreened group during the same time period. The participants comprised of 856 individuals born in 1915 and living in the municipality of Skellefteå in 1981. A randomly selected subgroup of the cohort (40%) was repeatedly screened every seventh year for 21 years with regular eye examination at the same hospital. Suspected OAG cases were followed until 2002 for the development of OAG. Medical records were collected and analysed for OAG to included visual fields, optic nerve head description and IOP measurement. The numbers of OAG cases were compared between the screened group and the unscreened group. The cohort consisted of 339 screened and 517 unscreened participants with a higher incidence of diagnosed OAG in women in the screened group. Before 1981, there were six cases of OAG in the screened group and nine cases in the unscreened group. During the follow-up period from 1981 to 2002, there were 33 new cases in the screened group and 31 new cases of OAG in the unscreened group. There was no significant difference between the two groups but only a tendency for higher proportion of diagnosis in the screened group possibly due to the small sample size.

Reference

Diagnosed open-angle glaucoma in screened versus unscreened subjects – a long-term age cohort study.
Astrom S, Stenlund H, Linden C.
ACTA OPHTHALMOLOGICA
2014;92:501-6.

ACTA OPHTHALMOLOGICA

Long-term outcomes for hereditary retinoblastoma
Reviewed by: Nana Theodorou
Vol 21 No 4
 

Earlier diagnosis and more rigorous treatment regimens have contributed to better outcomes for patients with retinoblastoma. This study looked at 24 patients with hereditary bilateral retinoblastoma treated with systemic chemotherapy during a ten year period (2001-2011). The medical notes were reviewed for demographic data, presenting clinical signs, heredity and treatment. Chemotherapy treatment consisted of four to six cycles of vincristine, etoposide and carboplatin (VEC), administered to all newly diagnosed patients with bilateral disease. The authors detail treatment regimens in detail for the interested reader and correlate the stage of the disease with the treatment received. The majority of patients (83%) responded to the treatment and all patients completed their chemotherapy. Altogether 26% (12 of 46) of the eyes received second-line therapy with a failure rate of 35% and mortality rate 0%. The mean follow-up was 60 months. The demographic data for all patients is nicely presented in a comprehensive table to include age, gender, age at diagnosis and stage of the disease. The results indicated that group A/B retinoblastomas have a distinct chemotherapy response, while group C/D/E tumours do not respond as well. The success rate was 65%; while patients have a good prognosis for life, approximately one-third of all hereditary cases received radiation therapy or underwent enucleation.

Reference

A 10-year experience of outcome in chemotherapy-treated hereditary retinoblastoma.
Bartuma K, Pal N, Kosek S A, et al.
ACTA OPHTHALMOLOGICA
2014;92:404-11.

ACTA OPHTHALMOLOGICA

Nystagmus and associated diagnosis
Reviewed by: Nana Theodorou
Vol 21 No 4
 

Patients with nystagmus attending a Low Vision clinic in Sweden were included in this study. Medical records were reviewed to exclude those with general diagnoses that could explain the nystagmus. The remaining group of patients underwent subjective refraction, retinoscopy, ocular motility, colour vision, ophthalmic examination and optical coherence tomography. Electroretinogram and genetic analyses were performed in some patients as indicated. The authors identified 62 patients with nystagmus as their main diagnosis with 43 of them having a major diagnosis other than nystagmus. Nystagmus was the major diagnosis in 19 patients, 15 of whom, aged 6-76 years, participated in the study. Two of the patients had foveal hypoplasia and albinism, four a seemingly isolated foveal hypoplasia, three achromatopsia, one rod-cone dystrophy, one degenerative high myopia, and two could not be evaluated. Only two patients appeared to have ‘congenital’ nystagmus. Eleven of the patients underwent a comprehensive genetic investigation of the PAX 6 gene. In addition, four of the patients were analysed for mutations in FOXC1 and PITX2 and one in FRMD7. No mutations were found in any of the patients analysed. The study illustrates that many patients in this select study group with nystagmus had associated underlying ophthalmic diagnoses. The authors conclude that early diagnosis is important to facilitate patient rehabilitation and provide appropriate family counselling.

Reference

‘Congenital’ nystagmus may hide various ophthalmic diagnoses.
Holmstrom G, Bondeson ML, Eriksson U, et al.
ACTA OPHTHALMOLOGICA
2014;92:412-6.

ACTA OPHTHALMOLOGICA

Retinal blood flow changes in glaucoma
Reviewed by: Nana Theodorou
Vol 21 No 4
 

This study examined the changes in retinal blood flow and vessel diameter after IOP reduction in high- and low-pressure glaucoma; exfoliation glaucoma (ExG) and normal-tension glaucoma (NTG). Glaucoma progression is seen at times in eyes despite IOP reduction and changes in blood flow have been previously detected in the ocular vasculature. The study recruited consecutive patients attending for deep sclerectomy; 17 eyes with ExG and 20 with NTG. Blood flow in the temporal peripapillary retina was measured with scanning laser Doppler flowmetry, and retinal vessel diameters were evaluated using the retinal vessel analyser. Investigations were carried out just before and three months after the operation and presented to include systemic flow, diastolic flow, mean flow and pulsation index in the temporal peripapillary retina. The results indicated that there were no differences between age, visual fields and number of topical medication. Preoperative IOP was significantly higher in ExG than in NTG (median 26 mmHg). Surgery reduced IOP significantly both in ExG eyes. After the operation, systolic retinal flow was significantly reduced in ExG eyes, whereas in NTG, HRF parameters remained unchanged. Preoperatively, the central retinal artery equivalent and arteriovenous ratio were higher in ExG than in NTG eyes. After IOP reduction, both were reduced in ExG eyes, but remained unchanged in NTG. The study concluded that there are local changes in blood flow related to IOP. Prior to IOP reduction, arterial diameter was larger in ExG eyes than in NTG eyes and this resulted in vasoconstriction and reduction of flow in ExG, whereas in NTG, both vessel diameter and retinal flow remained unchanged.

Reference

Change in retinal blood flow and retinal arterial diameter after intraocular pressure reduction in glaucomatous eyes.
Kurvinen L, Kyto J, Summanen P, et al.
ACTA OPHTHALMOLOGICA
2014;92:507-12.

AMERICAN JOURNAL OF OPHTHALMOLOGY

Comparison of two interferon gamma release assays (IGRA) for tuberculous uveitis
Reviewed by: Efrosini Papagiannuli
Vol 21 No 4
 

In this prospective cohort study the authors compared QuantiFERON-TB Gold In-Tube and T-SPOT.TB to evaluate their diagnostic accuracy. They enrolled 120 consecutive new uveitis presentations over a two year period in a tertiary centre. The majority were Chinese (61.3%), followed by Indian (20.8%) and Malay (6.6%). In total, 106/120 patients completed the follow-up for at least one year after completion of ocular and systemic treatment (including TB treatment where necessary); 43.4% presented with bilateral uveitis, 59.9% anterior, 2.6% intermediate and 15.1% posterior uveitis. 22.4% had panuveitis. The clinical signs suggesting possible underlying TB ranged from granulomatous inflammation in 25%, extensive posterior synechiae in 19.1%, vasculitis in 12.5% to serpiginous choroiditis in 0.7% (one patient). One patient had mycobacterium positive sputum sample and another patient had a positive urine sample (with a positive skin test and negative IGRA). All patients underwent ocular and systemic examination, baseline blood tests, CXR, Mantoux test, QuantiFERON-TB Gold In-Tube and T-SPOT.TB testing. The main outcome measures were the sensitivity and specificity of each test and their accuracy. The authors performed a meta-analysis of previously published literature on the prevalence of tuberculous uveitis (1987-2008) and found that recorded prevalences ranged from 0.06% (USA) to 10.5% (Saudi Arabia). The Bayesian analysis which was used for evaluation of the tests suggested that, regardless of the endemic prevalence of TB related uveitis, the QuantiFERON-TB Gold In-Tube was more specific but a little less sensitive than T-SPOT.TB and significantly more accurate in identifying tuberculous uveitis. The QuantiFERON-TB Gold In-Tube remained the more superior test after sensitivity analyses and varying the prevalence or probability of tuberculous uveitis. The authors conclude that in the absence of a gold standard test, a combination of any two IGRAs or traditional tests (skin testing), would improve the diagnostic accuracy. However, because of the high cost they recognise that further studies are needed to assess the most cost-effective combination and sequence of tests to assist in the diagnosis of tuberculous uveitis.

Reference

Prospective head-to-head study comparing 2 commercial interferon gamma release assays for the diagnosis of tuberculous uveitis.
Ang M, Wong WL, Kiew SY, et al.
AMERICAN JOURNAL OF OPHTHALMOLOGY
2014;157:1306-14.

AMERICAN JOURNAL OF OPHTHALMOLOGY

Outcomes of cataract surgery in patients with uveitis
Reviewed by: Efrosini Papagiannuli
Vol 21 No 4
 

This is a systematic, evidence-based literature review and meta-analysis, looking at the visual outcomes (vision 20/40 or better) of cataract surgery in uveitic eyes. The authors searched MEDLINE, EMBASE, CINHAL and CENTRAL, including English language and human studies only. They excluded conference abstracts, unpublished data, very small case-series, and studies reporting on combined procedures and intra-capsular cataracts extraction. Eighty-nine articles met the eligibility criteria out of 2815 articles. The authors standardised the results by determining the ratio of uveitic eyes in each study that achieved vision 20/40 or better after cataract surgery (95% confidence intervals). They found that 71% of eyes with quiet / mostly quiet uveitis of more than two months, at the time of surgery with intraocular lens implant (IOL), achieved the desired visual outcome of 20/40 or better postoperatively, versus 52% that were left aphakic. This was the case in 68% after phacoemulsification, 72% after extracapsular cataract extraction and 40% after pars plana lensectomy. Eyes with acrylic IOL or heparin-surface modified (HSM) polymethylmethacrylate had better outcomes (72%) than eyes with silicone IOLs (30%) or non-HSM polymethylmethacrylate (62%).The best visual outcome was achieved by patients with Fuchs heterochromic uveitis (92%), versus uveitis due to JIA (65%), intermediate uveitis (69%) or Behcet’s disease (36%). Studies regarding rarer uveitides like posterior uveitis, Vogt-Koyanagi-Harada syndrome (VKH), sarcoidosis and sympathetic ophthalmia were scarce and overall did worse with vision 20/40 or better achieved only in 40-49%. The authors highlight the limitations of their review, such as publication bias, the difficulty to adjust for various confounding attributes simultaneously (to account for prognostic characteristics), their use of a visual acuity metric, which evaluated the chance of gaining a visual acuity outcome rather than a frank visual improvement and the variability of the reported time-points, which overall were short-term. They conclude that more research is required to provide better evidence on which surgeons can confidently base their management of uveitic cataracts, with an emphasis on the individual clinical entities.

Reference

Outcomes of cataract surgery in patients with uveitis: a systematic review and meta-analysis.
Mehta S, Linton MM, Kempen J.
AMERICAN JOURNAL OF OPHTHALMOLOGY
2014;158:676-92.

BRITISH JOURNAL OF OPHTHALMOLOGY

An educational intervention to improve adherence to high-dosage patching regimen for amblyopia
Reviewed by: Jonathan Chan
Vol 21 No 4
 

This is a randomised trial of patients recruited between the periods of March 2006 and March 2008 from ophthalmology clinics in the Leicestershire area. A total of 62 children with newly diagnosed amblyopia were allocated randomly into two treatment arms with and without educational / motivational intervention material. The material they used included story books for children, information booklets for parents, a quotation booklet from parents and children, a passport arriving at each hospital visit, decorated patches, charts with stickers for each patching period of three weeks, a video with information about amblyopia and a special session with an orthoptist after three weeks of patching treatment. Both the treatment arms were given patching treatment of 10-hours per day, six days per week for a fixed period of 12-weeks’ duration. The intervention arm received an educational / motivational intervention as above before patching. The control arm received the usual clinical information as routine. The primary outcome measures were the adherence measured using electronic occlusion dose and monitors where a success / failure binary outcome was used to account for participants who dropped out of the study defined as patching >4 h/day. The secondary outcome is the visual outcome expressed as a percentage of visual deficit. It was reported by the authors that the intervention arm had increased the adherence success rates from 45.2% in the controlled group to 80.6% in the intervention group (p=0.0027). There was no significant difference between the two groups for the visual outcome (p=0.19). The authors concluded that the intense educational / motivational intervention can improve adherence to patching to high prescribed doses, but without any significant improvement of the visual outcome observed in this study. They recommended a larger multicentre trial to confirm these findings.

Reference

An educational intervention to improve adherence to high-dosage patching regimen for amblyopia: a randomised controlled trial.
Pradeep A, Proudlock FA, Awan M, et al.
BRITISH JOURNAL OF OPHTHALMOLOGY
2014;98:865-70.

BRITISH JOURNAL OF OPHTHALMOLOGY

Cataract surgery in small adult eyes
Reviewed by: Jonathan Chan
Vol 21 No 4
 

This is a retrospective audit of a five year study period, between the periods of January 2006 to December 2010, where a surgical log book search was performed. The inclusion criteria of this study were intraocular lenses (IOL) power greater than 30 D for anterior chamber fixated IOLs and greater than 35 D for posterior chamber-fixated IOLs. The other inclusion criteria for this study is a secondary intraocular lens implantation procedure and patients who had been left aphakic following primary operation to identify microphthalmic eyes that may not have received an intraocular lens implant at the same time as the cataract surgery. Exclusion criteria included an axial length greater than 20.9mm, previous intraocular surgery and other intraoperative surgical procedures apart from cataract surgery, and previous history of uveitis and surgeon in training. Forty-seven eyes fulfilled the criteria and were treated in two locations which include the Moorfields Eye Hospital and the Moorfields St Ann’s Cataract Centre. No serious intraoperative adverse events were recorded apart from the one case of iris prolapse with iris trauma, one case of endothelial corneal touch, one case of retinal detachment, two cases of postoperative inflammation and one case of chronic cystoid macular oedema. Postoperative corrective distance visual acuity was logMAR 0.3 or better in 24 eyes (62%) and only three eyes obtained worse vision. The overall ocular comorbidity rate was 53%. Ten microphthalmic eyes (26%) presented with associated congenital or hereditary pathology, and had worse visual outcomes (p<0.0001). Associated ocular diseases include: 51% study eyes include 10 eyes with congenital or hereditary pathology – one case of Leber congenital amaurosis, two cases of ocular cutaneous albinism, one case of retinal coloboma, one case of congenital cataract, three cases of retinitis pigmentosa and one case of corneal dystrophy. Acquired associated pathology include: six eyes with chronic angle closure glaucoma, two cases of pseudoexfoliation syndrome, one case of diabetic maculopathy and one case of Fuchs dystrophy. The authors conclude that microphthalmic eyes having high intraocular lens power are rare, and their presence is often associated with other ocular congenital or acquired conditions, as noted above. The authors conclude that the overall clinical outcomes were satisfactory and the surgical procedure affected by a low complication rate, as noted above.

Reference

Cataract surgery in small adult eyes.
Carifi G, Safa F, Aiello F, et al.
BRITISH JOURNAL OF OPHTHALMOLOGY
2014;98(9):1261-5.

BRITISH JOURNAL OF OPHTHALMOLOGY

Injection frequency and anatomic outcomes following conversion to Aflibercept in neovascular AMD patients
Reviewed by: Jonathan Chan
Vol 21 No 4
 

This is a retrospective study of patients with neovascular age-related macular degeneration (AMD) treated with intravitreal Lucentis and / or Avastin who were switched to aflibercept (Eylea). This study was carried out by the Casey Eye Institute retinal clinics, between May and September 2012. The inclusion criteria for the subjects are: [1] they had received at least 12 months of prior anti-VEGF therapy with either Avastin or Lucentis (for cases that had received one year anti-VEGF therapy prior to conversion with a ‘base-line study visit’ defined as the visit nearest to 12 months prior to conversion and an allowable range of 10-14 months prior to conversion); [2] visual acuity at conversion was ≥20/400 when switching to Eylea; [3] they completed 12 months (final ‘study visit’ defined as the visit nearest to 12 months following conversion and an allowable range 10-14 months) of Eylea injections without switching therapies. The outcomes in this study included:
1) The primary outcome was the mean number of injections in the year following the conversion to Eylea.
2) Secondary outcome include a change in the central macular thickness at six months and one year, presence of intraretinal (IRF) and subretinal fluid (SRF) at six months and a visual acuity at one year.
One hundred and nine patients were included in this study and the overall frequency of Eylea injections was unchanged with patients receiving 7.4 anti-VEGF injections a year prior to conversion compared with 7.2 Eylea injections in the year following (p=0.47). The change to Eylea was associated with improvement in central macular thickness from 324 to 295µ (p=0.0001 at six months) and 299µ (p=0.0047 at one year). There was no effect on the visual acuity at one year. In a particular sub-group analysis, patients who had received ≥10 anti-VEGF injections in the year prior had fewer injections (11.1 to 8.4, p=0.0001) and clinic visits (13.9 to 9.6, p<0.0001), as well as significant decrease in central macular thickness (CMT) (-35µ, p=0.02). The authors conclude that from the study group, switching to Eylea was not associated with any change in injection frequency or any improvement of the visual acuity. However, there is associated improvement in the CMT at six months and one year. For those sub-group analysis patients who have received at least 10 anti-VEGF injections in the year prior, transitioning to Eylea was associated with a reduction in injection frequency and also CMT, therefore suggesting that there is a potential cost saving in this particular sub-group of population of patients. The authors suggest that longer term research is needed with a prospective randomised trial with strict retreatment guidelines, and a monotherapy control would ideally answer some of the questions raised in this study.

Reference

Injection frequency and anatomic outcomes 1 year following conversion to Aflibercept in patients with neovascular age-related macular degeneration.
Messenger WB, Campbell JP, Faridi A, et al.
BRITISH JOURNAL OF OPHTHALMOLOGY
2014;98(9):1205-7.

CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY

Effect of phacoemulsification on trabeculectomy function
Reviewed by: Anjali Gupta
Vol 21 No 4
 

Previous studies have reported cataract surgery post trabeculectomy to be detrimental to IOP control. Conversely, other studies have reported phacoemulsification performed before trabeculectomy as a factor for bleb failure. The objective of this retrospective case control study was to evaluate the effect of phacoemulsification performed before or after trabeculectomy on IOP control. Forty-eight patients with primary open angle glaucoma (POAG) or primary angle closure glaucoma (PACG) were followed up for two years after trabeculectomy surgery. Eighteen patients had phacoemulsification subsequent to trabeculectomy (trab_phaco), and 30 patients were pseudophakic for greater than six months preceding trabeculectomy (phaco_trab). The primary outcome measures were target IOPs of A, ≤12mmHg; B, ≤15mmHg; C≤18mmHg with (qualified success) or without (unqualified success) additional topical treatment. Bleb failure was defined as the clinical need for additional topical antiglaucoma medication or further surgical intervention to achieve adequate IOP control. Bleb massage, suture removal or lysis, and postoperative 5-FU injections performed in clinics were permitted without constituting qualified success or failure. Results showed no significant difference in achieving the qualified and unqualified target IOPs in all groups A to C. In the first 12 months, significantly more trabeculectomies failed in the trab_phaco group (39%) compared with the phaco_trab group (10%). However, although this trend continued, failure rates between the two groups were not significant at 24 months.

Reference

Effect of phacoemulsification on trabeculectomy function.
Nguyen DQ, Niyadurupola N, Tapp RJ, et al.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2014;42:433-9.

CORNEA

Accelerated (9mW/cm2) corneal collagen cross-linking for keratoconus
Reviewed by: Sharmina Khan
Vol 21 No 4
 

This is one of many studies published / to be published on corneal collagen cross-linking that has a treatment time of 10 minutes compared to the previous Dresden protocol of 30 minutes to halt progression of keratoconus. Much has changed since the original Dresden protocol including the accelerated treatment protocol. Ex-vivo porcine and in-vivo confocal studies have shown that equivalent biomechanical changes in porcine corneas are achieved in the accelerated treatment protocol. The retrospective study had inclusion criteria very different to  National Institute of Health & Care Excellence (NICE) guidance in the UK, e.g. patients with subjective deterioration in vision. Only cases with mild-moderate (grade I-II Amsler-Krumeich classification) were included. Progression was defined as a decrease in visual acuity of at least one line (logMAR), increase in corneal steepness of one dioptre (steepest keratometry) over previous six months and >1D change in prescription of glasses / contact lenses over preceding two years. Sixteen eyes of 14 patients (three females, 11 males). No statistically significant difference was found in the mean corrected distance visual acuity (CDVA), mean refractive cylinder, mean manifest refraction spherical equivalent (SE), at six or 12 months post treatment. Corneal parameters K steep, K flat, corneal astigmatism, K mean and K maximum at the corneal apex were stable at six and 12 months in all patients. No complications were observed in the follow-up period. The study did not look at endothelial cell loss at these higher energy levels. No patient developed corneal decompensation or cataract formation. These results are encouraging and in keeping with other accelerated treatment reports at 12 months, however, a longer follow-up period is required.

Reference

Accelerated (9mW/cm2) corneal collagen cross-linking for keratoconus – a 1 year follow-up.
Elbaz U, Shen C, Lichtinger A, et al.
CORNEA
2014;33:769-73.

CORNEA

Squamous metaplasia of conjunctival epithelial cells with soft contact lens wear versus non-lens wearers
Reviewed by: Sharmina Khan
Vol 21 No 4
 

Conjunctiva is composed of non-squamous epithelial cells interspersed with goblet cells, which is a secretory epithelium. Squamous metaplasia is a transformation to non-secretory epithelium, ‘keratinised’ and enlargement of the conjunctival non-goblet cells and relatively shrunken nuclei are seen on impression cytology. These changes have been reported in soft contact lens wearers. This pilot study of impression cytology taken from interpalpebral conjunctiva of 23 white female soft contact lens wearers versus 23 age matched healthy white female optometry students. The aim of the study was to further define bulbar conjunctival cell morphology in squamous metaplasia in long-term contact lens wearers in an age-matched population. All contact lens wearers showed substantial cell changes compared with controls. The results indicate in concordance with other studies that squamous metaplasia can continue to develop or persist after an average of six years of successful contact lens wear. Comparison with other reports can be confusing due to the use of different grading scales. The authors report that nuclear pyknosis (shrinking of nuclear size) does not occur, rather there is enlargement of the nucleus along with the cell size. Such cellular changes don’t always correlate with “notable fluorescein staining of exposed bulbar conjunctiva.” This interesting report doesn’t correlate findings to clinical presentation to a hospital eye service with ocular surface discomfort associated with contact lens wear. Most of the subjects recruited reported mild occasional ocular surface discomfort associated with contact lens wear.

Reference

Objective assessment of squamous metaplasia of conjunctival epithelial cells as associated with soft contact lens wear versus non-lens wearers.
Doughty MJ.
CORNEA
2014;10:1095-102.

CURRENT EYE RESEARCH

Comparison of ganglion cell thinning in glaucoma vs. macular hole repair
Reviewed by: Khadijah Basheer
Vol 21 No 4
 

This prospective study compared the changes in the photopic negative response of the focal macular electroretinogram (fmERG) caused by retinal ganglion cell complex (GCC) thinning at the macula between patients with open angle glaucoma (OAG) and 12 months after successful macular hole repair surgery (MH). It has been shown that optical coherence tomography can determine the thickness of the GCC layer and that it can be used in diagnosing and monitoring progression in glaucoma patients. In addition, GCC thinning has been correlated to the functional loss of vision determined by visual field testing in glaucoma patients. In patients who have undergone successful macular hole repair surgery a dissociated optic nerve fibre layer appearance has been noted to occur. Thinning of the GCC layer has also been demonstrated in these patients, however, any functional visual correlation to this postoperative thinning remains controversial. In this study there was significant thinning of the GCC layer in both the OAG group and MH group compared to healthy controls. However, whilst the OAG group showed a significant reduction in fmERG response, there was no significant reduction in fmERG in the MH group compared to the control group. The results show that although the GCC layer is thinned in the MH the function of GCCs remains preserved. However, in the study limitations they postulate whether longer follow-up of these patients may then reflect a possible reduction in GCC function. The study shows an interesting finding of preservation of macular function demonstrated by fmERG in patients who have undergone macular hole repair surgery, where the GCC layer is thinner than control subjects in contrast to patients with early glaucoma who have similar GCC thinning but demonstrate functional loss through fmERG. However, it remains unclear as to why this difference occurs and further study is needed before any final conclusions can be made.

Reference

Differences in functional loss associated with ganglion cell complex thinning between patients with glaucoma and postoperative macular hole.
Machida S, Tamada K, Ohzeki T, et al.
CURRENT EYE RESEARCH
2014;39(8):845-52.

CURRENT EYE RESEARCH

Meibomian gland dropout in patients with dry eyes
Reviewed by: Khadijah Basheer
Vol 21 No 4
 

In this prospective study 264 patients with symptoms of dry eye were examined with a non-contact meibography system to assess the morphological changes in their meibomian glands. These patients were not previously diagnosed with meibomian gland dysfunction and patients with active or previous ocular surface disease other than dry eye were excluded. The meibography system was composed of a slit-lamp with an infrared transmitting filter and video camera. The eyelids of patients were everted and the meibomian glands observed. Partial or complete loss of meibomian glands was scored from 0 (no loss of glands) to three (loss of area greater than two thirds). They were able to demonstrate a variety of morphological changes including shortened, tortuous, expanded and lost meibomian glands. They found a negative correlation between the meibomian gland score and Schirmers testing and tear film break up time and a positive correlation with fluorescein staining of the cornea. These results suggest that although meibomian gland dysfunction may not be clinically apparent there are morphological changes in patients with dry eyes and these patients should be counselled on how to treat meibomian gland dysfunction to improve their symptoms of dry eye. However, this study did not compare their findings to any control group and therefore we do not know how much variance there may be in meibomian gland morphology in the general population.

Reference

Meibomian gland dropout in patients with dry eyes.
Feng Y, Gao Z, Feng K, et al.
CURRENT EYE RESEARCH
2014;39(10)965-72.

CURRENT EYE RESEARCH

Short-term effects of intravitreal bevacizumab on the cornea
Reviewed by: Khadijah Basheer
Vol 21 No 4
 

Bevacizumab has been extensively used to treat macula oedema and neovascularisation of the retina and it has also been useful in the management of corneal neovascular diseases. This prospective study aimed to provide more information on the effect bevacizumab may have on the cornea as there is little known about potential corneal toxicity compared to the retina. A higher dose of bevacizumab, 2.5mg/0.1ml was injected intravitreally into 43 eyes. The subjects and a control group were studied for one month and the following measurements were taken: central corneal thickness, intraocular pressure, simulated keratometry, anterior chamber depth and iridocorneal angle. No side-effects or corneal endothelial toxicity was observed and after one month there was no statistical difference in any of the above measurements. The authors conclude from this short study that a one off dose of intravitreal bevacizumab has no toxic effects on the cornea. However, the follow-up period was only one month, we do not know whether any later effects become apparent after one month, what occurs after multiple injections of bevacizumab or the effects of injecting bevacizumab into the cornea itself. More research into this area is needed to provide further confidence regarding the safety of bevacizumab on the cornea and anterior chamber structures.

Reference

Short term effects of intravitreal bevacizumab on the cornea.
Guler M, Capkin M, Simsek A, et al.
CURRENT EYE RESEARCH
2014;39(10):989-93.

EXPERIMENTAL EYE RESEARCH

A mouse model for uveal melanoma
Reviewed by: Graham Wallace
Vol 21 No 4
 

Uveal melanoma (UM) is the most common malignant tumour arising within the eye and is a severe threat for both sight and life, due to a high risk of metastasis. There are no animal models of UM, but the Tg(Grm1) in which the glutamate receptor 1 (Grm1) transgene is under the control of the melanocyte specific dopachrome tautomerase (Dct) promoter, was developed as a model for skin melanoma. As Dct is expressed in all melanocytes the authors assessed the Tg (Grm1) mouse for signs of ocular melanoma. The results showed choroidal thickening, and uveal melanocyte neoplasia using melanocytic markers S100B and MelanA. Importantly, analysis of human UM samples showed expression of Grm1, suggesting that glutamate signalling is involved in human disease. These results identify the Tg(Grm1) mouse as a new model for uveal melanoma that should allow for further dissection of the mechanisms involved in imitation and a therapeutic model for drug testing.

Reference

Tg(Grm1) transgenic mice: a murine model that mimics spontaneous uveal melanoma in humans?
Schiffner S, Braunger BM, de Jel MM, et al.
EXPERIMENTAL EYE RESEARCH
2014;127:59-68.

EXPERIMENTAL EYE RESEARCH

Ovarian hormones drive onset of Sjogren’s disease in mice
Reviewed by: Graham Wallace
Vol 21 No 4
 

Sjogren’s syndrome (SS) is a debilitating, sight-threatening, systemic autoimmune disease with no effective treatment available. SS is characterised by lacrimal gland lymphocytic infiltration and epithelial cell death, as well as by the presence of serum autoantibodies. Patients have severe dry eyes and are at high-risk of developing corneal perforation and blindness. To investigate the onset of SS in mouse models previous studies have reported that removal of the ovaries accelerated disease in susceptible mice, with lymphocytic infiltration preceding goblet cell apoptosis. In this paper cytokine levels in ovarectomised mice were studied. The results show that levels of proinflammtory cytokines interleukin-1β, tumour necrosis factor-α and IL-4 were elevated early after surgery which anti-inflammatory IL-10 was only raised at later time points. These changes were not seen in resistant mouse strains following ovarectomy. Likewise increased levels of anti-Ro/SSA were seen in susceptible strains only. Physiological doses of E2 or dihyrotestosterone (DHT) at time of OVX prevented the upregulation of cytokines and the presence of autoantibodies in these animals. These data show a strong link between ovarian hormones and onset of SS in mice of the appropriate genetic background. Genome-wide association studies have identified several genes to be linked to SS including some involved in the immune response. Coupled with the female predisposing to this condition this paper identifies novel pathways involved in the onset of SS that should be explored

Reference

Time course of cytokine upregulation in the lacrimal gland and presence of autoantibodies in a predisposed mouse model of Sjogren’s syndrome: The influence of sex hormones and genetic background.
Czerwinski S, Mostafa S, Rowan VS, Azzarolo AM.
EXPERIMENTAL EYE RESEARCH
2014;128:15-22.

EXPERIMENTAL EYE RESEARCH

RPE use similar pathway to regulatory T cells to inhibit immune response
Reviewed by: Graham Wallace
Vol 21 No 4
 

Retinal pigment epithelial (RPE) cells form an important part of the blood-retinal barrier that protects the neuronal cells responsible for sight. RPE cells are involved in innate and adaptive immune responses via expression of surface molecules and release of cytokines. However, RPE cells under normal conditions are anti-inflammatory, a function linked to expression of molecules such as FasL and the release of immunosuppressive molecules. In this paper the authors show that CD73, a GPI-anchored nucleotidase expressed on RPE cells abrogated immune responses in the animal model experimental autoimmune uveoretinitis. Proinflammatory adenosine triphosphate (ATP) is released during inflammation and is converted to adenosine monophosphate (AMP) by CD39 and to anti-inflammatory adenosine by CD73. The results show that normal mouse RPE shows strong expression of CD73, which was significantly reduced in inflamed eyes or RPE from inflamed eyes. In an in vitro chamber assay CD73-poitive RPE cells inhibited T cell activation on addition of AMP, whereas CD73-negative cells did not. CD73 has been described as a marker of regulatory T cells and this paper demonstrates that it performs a similar function in RPE cells to protect the retina from deleterious immune responses.

Reference

CD73 expression in RPE cells is associated with the suppression of conventional CD4 cell proliferation.
Chen S, Zhou S, Zang K, et al.
EXPERIMENTAL EYE RESEARCH
2014;127:26-36.

JAMA OPHTHALMOLOGY

Are single IOP measurements adequate for estimating the effect of IOP lowering interventions?
Reviewed by: Lona Jawaheer
Vol 21 No 4
 

The World Glaucoma Association recommends that, to assess the effect on intraocular pressure (IOP) of medication or surgery, the mean of multiple measurements of postoperative IOP is a better reflection of IOP than a single measurement of postoperative IOP. The authors hypothesised that a single IOP measurement might approximate the mean of several measurements. Pre-randomisation data from the COMPASS study was analysed by the authors. A total of 609 patients (609 eyes) with primary open-angle glaucoma and cataract were included. A single randomly-timed IOP measurement was made at the screening visit while the patient was still receiving their usual glaucoma medication regimen. The medications were then discontinued (for pre-specified periods of time) and, at a baseline visit following complete medication washout, IOP measurements were taken at 8am, 12pm and 4pm. The authors calculate the proportion of eyes in which the increase in IOP after washout, using the mean of the three measurements, differed by more than 0.5, 1.0, 1.5, or 2.0mmHg from the increase in IOP after washout using only one of the post washout measurements. The mean (SD) IOP before washout was 18.5 (4.0) mmHg. The mean increase in IOP after washout, using the mean of the three measurements, was 5.3 (4.2) mmHg. The percentage of eyes in which the increase in IOP using a single post washout IOP differed from the increase in IOP using the mean of three measurements by more than 1.5mmHg was 35.1%, 25.6%, 34.2%, 30.0% and 31.4% when the single measurement was made at 8am, 12pm, 4pm, a randomly chosen single measure of those three times, and the time closest to that of the prewash out IOP, respectively. As more than 10% of the eyes (previously agreed cut-off) had a difference greater than 1.5mmHg for all single measurements, compared to the mean of three IOP measurements, the authors concluded that single IOP measurements are not a reliable replacement for multiple diurnal IOP measurements for IOP lowering medication, although they might be for post-surgical interventions, as the diurnal variation post-surgery is known to be narrower.

Reference

Single vs multiple intraocular pressure measurements in glaucoma surgical trials.
Zhang ML, Chon BH, Wang J, et al.
JAMA OPHTHALMOLOGY
2014;132(8):956-62.

JAMA OPHTHALMOLOGY

Do topical steroids improve visual outcome in the treatment of bacterial keratitis?
Reviewed by: Lona Jawaheer
Vol 21 No 4
 

The use of topical corticosteroids as an adjunctive treatment to antibiotics in the management of bacterial keratitis remains a controversial issue. The results of the Steroids for Corneal Ulcers Trial (SCUT) – a randomised, double-masked, placebo-controlled trial that recruited patients at two US centres and one centre in India – were published in 2012 and showed that adding topical corticosteroids to topical moxifloxacin hydrochloride in bacterial keratitis did not appear to have a beneficial effect on best spectacle corrected visual acuity (BSCVA) at three months. The authors of this article hypothesised that the trial did not take into account the timing of the corticosteroid / placebo treatment with respect to the start of the antibiotic drops, and that the true effect of corticosteroid treatment could therefore have been masked. The improvement in BSCVA at three months was calculated in the groups that received corticosteroids / placebo early (within two to three days of starting antibiotics) or late. In the early group, use of corticosteroids was associated with a –0.11 logMAR BSCVA improvement (n=311; 95%CI, –0.20 to –0.02; P=.01) compared with placebo group. In the late group, corticosteroid treated patients had one-line worse visual acuity than did the placebo-treated patients, although this effect was not significant (n=139; 0.10 logMAR; 95%CI, –0.02 to 0.23; P=.14). The benefit of early administration of corticosteroids was maintained for mild, moderate and severe ulcers. When patients with Nocardia keratitis were excluded from the multiple linear regression model, corticosteroids were beneficial when administered earlier and neutral when administered later. Corticosteroids have been shown to adversely affect outcome in cases of fungal or Acanthamoeba keratitis. In the SCUT trial, patients with Nocardia keratitis were also adversely affected by corticosteroids. Therefore, it is important to be certain of the diagnosis prior to starting corticosteroids. These results suggest that early administration of corticosteroids in bacterial corneal ulcers might result in a better visual outcome for the patient.

Reference

Early addition of topical corticosteroids in the treatment of bacterial keratitis.
Ray KJ, Srinivasan M, Mascarenhas J, et al.
JAMA OPHTHALMOLOGY
2014;132(6):737-41.

JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS

Amblyopia treatment review
Reviewed by: Fiona Rowe
Vol 21 No 4
 

This review paper summarises the main causes and neural mechanisms that characterise amblyopia. The authors analysed neuroanatomical, neurophysiological and electrophysiological studies in the literature to better understand actual treatment regimens and evaluate new therapeutic possibilities. They considered causes of strabismus, anisometropia and deprivation amblyopia. Treatment options included surgical correction of strabismus, cataract and ptosis, refractive correction, occlusion and penalisation, perceptual learning, transcranial magnetic stimulation and binocular treatment. Drug therapies included Carbidopa-Levodopa, phenylethylamine, citicoline and Bicuculline. These substances may be able to promote the recovery of visual function in partially sighted patients and make a more stable and long-lasting treatment.

Reference

Amblyopic treatment strategies and new drug therapies.
Pescosolido N, Stefanucci A, Buomprisco G, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:78-86.

NEURO-OPHTHALMOLOGY

A rare case of post-traumatic central retinal artery occlusion
Reviewed by: Claire Howard
Vol 21 No 4
 

Central retinal artery occlusion is rarely associated with traumatic optic neuropathy, this case report details of one such case. The reported case is of a ten-year-old boy presenting after a fall from height with loss of vision in one eye. Vision was reduced to no perception of light and a CT scan revealed fractures of the medial orbital wall and roof and a diagnosis of traumatic optic neuropathy with central retinal artery occlusion was made. Surgical intervention was performed within 24 hours with optic canal decompression through a transorbital route. Postoperatively the child’s vision returned to 6/9 within one month, which was maintained at a five year follow-up. This highlights the possibility of a local decompression of the optic nerve using a transcaruncular-transorbital approach combined with direct fibrinolysis, which in this case provided an excellent visual outcome.

Reference

Optic canal decompression and direct ophthalmic artery fibrinolysis for traumatic optic nerve neuropathy with central retinal artery occlusion.
Vaitheeswaran K, Kaur P, Garg S, Nadar M.
NEURO-OPHTHALMOLOGY
2014;38(3):127-30.

NEURO-OPHTHALMOLOGY

Choroidal and macular thickness in nonarteritic anterior ischaemic optic neuropathy
Reviewed by: Claire Howard
Vol 21 No 4
 

This study evaluates the choroidal and macular thickness in patients with chronic nonarteritic anterior ischaemic optic neuropathy (NA-AION). Two groups of subjects were compared, group one included 20 eyes with chronic NA-AION and group two, 31 healthy control eyes. The control group was demographically similar to the affected group. In both groups, choroidal and macular thickness was measured using the enhanced depth imaging program of Heidelberg Spectralis® optical coherence tomography. Macular thickness was found to be reduced in eyes that had an episode of NA-AION. Choroidal thickness was found to generally be higher in affected eyes compared to healthy controls. This increase in choroidal thickness was attributed by the authors to a local dysfunction in vascular autoregulatory mechanisms. The results show a change in choroidal thickness with chronic NA-AION. Future studies are required to test the potential of these findings for the future identification of patients at risk of this devastating eye condition, or in the follow-up of identified patients.

Reference

Choroidal thickness in nonarteritic anterior ischaemic optic neuropathy: a study with optical coherence tomography.
Dias-Santos A, Ferreira J, Abegao Pinto L, et al.
NEURO-OPHTHALMOLOGY
2014;38(4):173-80.

NEURO-OPHTHALMOLOGY

Early intraocular complications of aneurysmal subarachnoid haemorrhage
Reviewed by: Claire Howard,
Vol 21 No 4
 

The aim of this study was to estimate the incidence of a whole spectrum of early intraocular complications in patients suffering from aneurysmal subarachnoid haemorrhage (SAH) and to identify factors that are potentially associated with these fundus findings. In total the authors analysed 96 cases of aneurysmal SAH. Forty patients (42%) had abnormal fundus findings, these included disc swelling in 13.5%, retinal haemorrhages in 23% and vitreous haemorrhage in 5%. The incidence of intraocular pathologies was significantly higher in patients who lost consciousness at the onset of SAH, were admitted with high scores of the Hunt-Hess and Fisher scales and low score of the Glasgow Coma Scale, as well as in those with arterial hypertension, more sizeable aneurysm and older patients. In summary, the risk factors for intraocular complications included the severity of SAH, loss of consciousness, larger aneurysm, older age and arterial hypertension.

Reference

Early intraocular complications of subarachnoid haemorrhage after aneurysm rupture.
Obuchowska I, Turek G, Mariak Zenon, Mariak Zofia.
NEURO-OPHTHALMOLOGY
2014;38(4):199-205.

NEURO-OPHTHALMOLOGY

Effect of oxygen levels on binocular summation of dark vision
Reviewed by: Claire Howard
Vol 21 No 4
 

Previous studies have reported conflicting results on the existence of binocular enhancement of dark vision. This study compares monocular and binocular absolute thresholds of dark adaptation in two different populations (healthy individuals and those with chronic respiratory insufficiency). The study aims to answer the previously unresolved questions regarding binocular summation at absolute threshold. Study Group A consisted of 18 healthy individuals, Group B recruited 13 patients with respiratory failure. All recruits in both groups were examined by computerised dark adaptometry on three separate visit days. Group B received oxygen supplement at visits one and three, but not at visit two. In group A, binocular dark adaptation was significantly more sensitive than monocular adaptation across all three visits. In group B, at visits one and three, binocular dark adaptation was also significantly more sensitive than monocular. However, at visit two, when no oxygen supplement was given, no significant difference was found between binocular and monocular summation. This study goes some way to answering questions regarding binocular summation in reporting that a deficit in oxygen seems to affect the binocular adaptation, and that binocular summation exists at absolute threshold.

Reference

Two eyes are better than one – binocular summation of dark vision in healthy individuals and patients with chronic respiratory disease.
Thylefors J, Havelius U.
NEURO-OPHTHALMOLOGY
2014;38(3):113-21.

NEURO-OPHTHALMOLOGY

Gender and ethnicity related differences in optic nerve head
Reviewed by: Claire Howard
Vol 21 No 4
 

The authors investigated the effect of ethnicity and gender on optic nerve head morphology comparing Indian and Caucasian males and females. The optic nerve head was investigated using spectral-domain optic coherence tomography (SD-OCT). Results showed that disc and rim areas were larger in Caucasian males compared to females, but smaller in Indian males compared to females. Overall, Indian subjects had a significantly larger cup area and volume, but there was no difference in retinal nerve fibre layer between the two groups. These study findings should be considered when assessing a variety of patients in a clinical setting. Care should be taken when comparing patients’ recordings with normative data supplied with OCT machines as these often don’t include gender and ethnicity differences, making results difficult and inaccurate to interpret.

Reference

Gender and ethnicity-related differences in optic nerve head topography in healthy Indian and Caucasian participants.
Pilat AV, Gottlob I, Sheth V, et al.
NEURO-OPHTHALMOLOGY
2014;38(4):205-13.

NEURO-OPHTHALMOLOGY

Ocular blood flow changes in Behcet disease
Reviewed by: Claire Howard
Vol 21 No 4
 

This study evaluates ocular blood flow changes in both ocular Behcets disease (BD) and non-ocular BD (with or without thrombotic disease) and compares these findings with a healthy control group. A total of 90 eyes with BD were evaluated with a range of ocular involvement from no involvement to active uveitis. These affected eyes were compared with 120 matched control eyes. All eyes were measured using colour Doppler ultrasonography (CDU) assessing ophthalmic, central retinal and ciliary artery flow parameters. Results from this significant sample size showed major haemodynamic changes in the ophthalmic vessels of ocular Behcet patients. In addition, in non-ocular BD patients with thrombolysis, blood flow parameters were affected more than those without thrombolysis and healthy controls. This suggests that CDU may detect ocular blood flow alterations before ocular clinical manifestations appear in BD patients, creating opportunity for earlier interventions.

Reference

Ocular blood flow changes in Behcet disease patients with/without thrombotic disease.
Yuksel H, Turkcu FM, Hamidi C, et al.
NEURO-OPHTHALMOLOGY
2014;38(3):122-6.

NEURO-OPHTHALMOLOGY

Ocular ischaemic syndrome in a rat model
Reviewed by: Claire Howard
Vol 21 No 4
 

Ocular Ischaemic syndrome is a devastating eye disease caused by severe carotid stenosis. This study’s purpose was to develop a reliable rat model for this syndrome by subjecting rats to common carotid artery occlusion and sham surgery. Rats were assigned into one of two groups receiving different procedures, the sham surgery group and the stenosis group. For this study, the common carotid artery in the rat model was ligated unilaterally or bilaterally with needles of different diameters and the ocular arterial filling time examined by fluorescein fundus angiography at different time intervals. Bilateral common carotid artery occlusion was a more effective model than unilateral occlusion. Results showed that the arterial filling time was significantly increased at 14 and 21 days after ligation compared with preoperatively. The total blood flow in the sham surgery group was significantly higher than in the bilateral common carotid artery occlusion group. The fundus blood flow was statistically different between the two groups, whereas that of the anterior segment was not. The authors have concluded that a successful rat model of ocular ischaemic syndrome has been achieved and that this was reliable up to two to three weeks after surgery. This model could potentially be used in future research and in the investigation of new treatments.

Reference

Bilateral common carotid artery occlusion in the rat as a model of retinal ischaemia.
Huang Y, Fan S, Li J, Wang Y-L.
NEURO-OPHTHALMOLOGY
2014;38(4):180-9.

NEURO-OPHTHALMOLOGY

Reliability of kinetic perimetry in children and young adults
Reviewed by: Claire Howard
Vol 21 No 4
 

This study reports on normative visual field area, feasibility and repeatability of testing for a large sample size of healthy children and young adults, using Octopus semi-automated kinetic perimetry. Sample included 221 healthy volunteers aged 5-22 years. The study was performed following a literature search which indicated stark disagreement on the rate of peripheral visual development and age of peripheral visual maturation. If semi-automated kinetic perimetry is to be performed in a clinical setting, availability of normative data for visual fields at a given age, expected ability and reliability is essential. Octopus kinetic perimetry is fast becoming the visual field test of choice in many clinics and as such, expected feasibility and normative visual field and blind spot data are required, especially for children. Reliable visual fields were plotted in 23% of participants <10 years, 64% of 10-12-year-olds and 98% aged 13-22 years. Reaction times reduced with age. Visual fields were assessed using I4e and I2e stimuli at 5°/second or 3°/second. Visual field areas were unchanged with age using 5°/second, but increased using 3°/second for I2e. Therefore, a test speed of 5°/second is recommended for healthy children and adults. The study found that participants aged 13 years or older and approximately 2/3 aged 10-12 years can reliably perform kinetic perimetry on the octopus perimeter. Although testing is possible with younger children, the authors recommend exercising caution when interpreting the test results from children under 13 years of age.

Reference

Peripheral visual fields in children and young adults using semi-automated kinetic perimetry: feasibility of testing, normative data and repeatability.
Bjerre A, Codina C, Griffiths H.
NEURO-OPHTHALMOLOGY
2014;38(4):189-99.

NEURO-OPHTHALMOLOGY

Two case reports of late onset adbucens nerve palsy following carotid-cavernous fistula treatment
Reviewed by: Claire Howard
Vol 21 No 4
 

This report presents two cases of abducens palsy developing with late onset following endovascular treatment for carotid-cavernous fistula. Following this common and effective treatment for carotid-cavernous fistula, an immediate cranial nerve palsy is a common finding. It usually resolves spontaneously. In both these cases, total obliteration of the fistula without a residual shunt was confirmed. However, both cases went on to develop late onset abducens nerve palsy months after the procedure. Both cases went on to require strabismus surgery to treat their ocular motility disorders. The underlying mechanism is unknown and the authors suggest it may be a different mechanism to that of immediate or delayed cranial nerve palsies, due to the fact that the symptoms in these cases did not resolve.

Reference

Late-onset abducens nerve palsy after endovascular treatment for carotid-cavernous fistula: two case reports.
Liu Y-L, Hsieh Y-H, Tsai T-H.
NEURO-OPHTHALMOLOGY
2014;38(3):131-4.

OCULAR IMMUNOLOGY AND IMFLAMMATION

Choroidal thickness in ocular sarcoidosis by OCT measurement
Reviewed by: Nikolaos D Georgakarakos
Vol 21 No 4
 

This is the first study to evaluate the choroidal thickness in patients with ocular sarcoidosis during the quiescent phase using enhanced depth imaging optical coherence tomography (EDI-OCT) and comparing with normal subjects. Ocular sarcoidosis may affect the choroidal circulation (occlusive arteriolitis) which may induce the reduction of the choroidal thickness. During the inflammatory phase the thickness of the choroid may change. The study included 18 eyes of nine patients with ocular sarcoidosis (eight women and one man mean age 59 years +/-18.5) and their subfoveal choroidal thickness was measured using EDI-OCT and compared to the age, sex and spherical equivalent-matched normal subjects. The mean subfoveal choroidal thickness was 281.76+/- 88µm in patients with sarcoidosis and 432+/-71µm in controls. Significant differences were found at points between the nasal 1500µm and temporal 1000µm to the fovea between patients and control group (p=0.002 at fovea). Therefore, the patients with sarcoidosis had thinner choroidal layer in the quiescent phase when compared to control subjects.

Reference

Choroidal thickness in ocular sarcoidosis during quiescent phase using enhanced depth imaging optical coherence tomography.
Gungor SG, Akkoyum I, Reyhan NH, et al.
OCULAR IMMUNOLOGY AND IMFLAMMATION
2014;22(4):287-93.

OCULAR IMMUNOLOGY AND IMFLAMMATION

Diagnostic procedures in vitreoretinal lymphoma
Reviewed by: Nikolaos D Georgakarakos
Vol 21 No 4
 

This paper presented a retrospective review of medical records of HIV negative immunocompetent patients diagnosed with vitreoretinal lymphoma between 1994 and 2012. The aim of the paper was to evaluate the type and number of diagnostic interventions required to confirm the presence of vitreoretinal (VR) lymphoma. Twenty-seven cases were included. Of the 27 cases, diagnosis using pars plana vitrectomy was made in 13 (48%), vitreous tap in two (7.5%) and anterior chamber tap in one (3.7 %), chorioretinal biopsy in two (7.5%), brain biopsy in five (18.5%) and cerebrospinal fluid cytology via lumbar puncture in four (14.8%). Ten patients (37%) had definitive results on the first procedure and 17 (63%) had at least one false negative. Vitrectomy was the most common procedure and patients required a mean of 2.1 procedures. The average time from onset of symptoms to confirmed histopathological diagnosis was 13.9 months. VR lymphoma, a common masquerade uveitic syndrome, is difficult to recognise and requires a high degree of clinical suspicion. Most patients were initially thought to have idiopathic uveitis and treated with systemic corticosteroids. Treatment with corticosteroids at the time of vitrectomy may further complicate the diagnosis by leading to lysis of the lymphoma cells and false negative results of the vitreous samples. In this study none of the patients were on corticosteroid therapy at the time of vitreous sampling.

Reference

Diagnostic procedures in vitreoretinal lymphoma.
Dalal M, Casady M, Moriarty E, et al.
OCULAR IMMUNOLOGY AND IMFLAMMATION
2014;22(4):270-6.

OCULAR IMMUNOLOGY AND INFLAMMATION

Polymerase chain reaction evaluation of infectious multifocal serpiginoid choroiditis
Reviewed by: Nikolaos D Georgakarakos
Vol 21 No 4
 

This paper presents a retrospective review of infectious agents associated with multifocal serpiginous choroiditis (MSC) based on polymerase chain reaction (PCR) evaluation and specific antimicrobial therapy. The study included 13 patients with MSC who were evaluated with PCR for the following organisms: mycobacterium tuberculosis (MTB), herpes simplex virus 1 (HSV1), Varizella zoster virus (VZV) and cytomegalus virus (CMV). Nine (69%) were positive for one or more organisms. Seven (54%) were positive for MTB, three (23%) for CMV. Nine patients completed six months follow-up and six resolved completely. Two continued to have lesions and one CMV positive required further additional valgancyclovir treatment. In this study the authors used multitarget PCR for MPB64 gene rather than the conventionally used multicopy element IS6110 because it gives better diagnostic yield. All but one of these patients showed complete resolution of inflammation following antiTB and steroid treatment. Tuberculosis (TB) remains the commonest and most important cause for MSC and PCR (of ocular fluid samples) can be a useful diagnostic tool. However, the role of HSV still remains to be established.

Reference

Polymerase chain reaction evaluation of infectious multifocal serpiginoid choroiditis.
Mohan N, Balne PK, Panda KG, et al.
OCULAR IMMUNOLOGY AND INFLAMMATION
2014;22(5):384-90.

OPHTHALMIC PLASTIC & RECONSTRUCTIVE SURGERY

A tarso-conjunctival flap for paralytic ectropion
Reviewed by: James Hsuan
Vol 21 No 4
 

This is a review of 110 patients with paralytic ectropion who underwent a lateral tarso-conjunctival flap procedure. The technique involves fashioning a 4-8mm wide lateral tarso-conjunctival flap in a similar way to a lateral Hughes flap. This is then sutured to the de-epithelialised margin of the lateral lower lid posterior lamellar. In the 45 patients who also had significant horizontal laxity, a simultaneous lid tightening was performed with a modified lateral tarsal strip. Lagophthalmos and lid retraction improved in all cases, but unfortunately there is no data regarding the degree of improvement. Ocular surface exposure and keratopathy also improved in all patients. Complications were relatively rare and minor and patients reported high levels of satisfaction with the surgery. Interestingly there was even some improvement in lower lid movement on eye closure, which the authors suggest was due to a Bells’ phenomenon resulting in the upward movement of the superior fornix, which then exerts an additional lift on the lower lid via the flap. One drawback is potential loss of some temporal field, although this may be improved by trimming back the flap without a significant loss of effect on the lower lid position. The technique looks to have merit and has not been published previously. The authors acknowledge the limitations of a retrospective series, but the lack of long-term follow-up data is a particular drawback in patients with paralytic ectropion.

Reference

Lateral tarsoconjunctival only flap lower eyelid suspension in facial nerve paresis.
Tao JP, Vemuri S, Patel AD, et al.
OPHTHALMIC PLASTIC & RECONSTRUCTIVE SURGERY
2014;30:342-5.

OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY

Factors affecting the success of canalicular repairs
Reviewed by: James Hsuan
Vol 21 No 4
 

This is a ten year retrospective review of 137 canalicular laceration repairs, looking for factors which affected the outcome. A successful outcome was defined as no epiphora at three months or more after removal of the stent. Overall the success rate was 72%, but 86% of repairs done in an operating theatre were successful compared with 37% of those done in a minor procedures room. Level of training was also a major determinant, with a fellowship trained oculoplastic consultant achieving 84% success, oculoplastic fellows 44%, non-oculoplastic consultants 29% and residents 25%. There was no significant difference comparing monocanalicular with bicanalicular intubation, but only 17 patients had bicanalicular stenting. The vast majority of those left with epiphora found it bothersome to some degree. The authors admit that lack of epiphora is not the same as anatomical patency, and using this criterion alone probably overestimates the success of surgery. There is no analysis of outcomes comparing upper lid lacerations with lower lids, but the authors recommend all canalicular lacerations are repaired. This is the first publication to address the specific factors of level of training and location of surgery as determinants of success in canalicular repairs. The highly significant difference in success rates make a strong case for recommending that all canalicular repairs should be done by, or supervised by, an oculoplastic trained consultant in main theatres.

Reference

Canalicular laceration repair: an analysis of variables affecting success.
Murchisan AP, Bilyk JR.
OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY
2014;30:410-4.

OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY

Outcomes and complications of supramaximal levator resection
Reviewed by: James Hsuan
Vol 21 No 4
 

This is a report of 35 children with unilateral congenital ptosis who underwent a supramaximal levator resection, involving extensive dissection of levator including cutting Whitnall’s ligament. The average preoperative margin reflex distance to the upper lid (MRD1) was 0.5mm, and the average levator function was 6.6mm. Photographic analysis at least six months post-surgery showed the average MRD1 had improved to 3.4mm, and the difference in MRD1 with the fellow eye had reduced from 3.1mm to 0.1mm, with 80% of patients having 1mm or less of asymmetry. There were minor contour abnormalities in 29% and 31% had lash ptosis. Fourteen patients also underwent assessment of their blink amplitudes, both spontaneous and when looking from primary to 30 degrees of downgaze, using a magnetic search coil. Blink amplitudes were very poor on the first postoperative day, requiring intense lubrication and Frost sutures for the first week. They remained reduced at a mean of 37 months post-surgery, when the average spontaneous blink amplitude was 37%, and the downward saccadic movement 55%, of the fellow eye amplitudes. The discussion describes how our understanding of Whitnall’s ligament has evolved, with reasons to question the traditional view of it as either a significant supporting structure or a fulcrum to change the direction of pull of the levator muscle. These previously held concepts have been reasons to avoid supramaximal surgery which requires cutting Whitnall’s. The authors admit the procedure remains contentious, but also explain that the alternatives are limited. Unilateral brow suspension in the absence of compensatory ipsilateral frontalis overaction is often unsatisfactory, and parents usually refuse bilateral surgery. The technique lifts the lid well, but has the drawback of exposure from reduced blink amplitudes and should not be used if there is a poor Bell’s reflex. Contour defects and lash ptosis also occur, but the latter can be reduced by careful re-fixation of the tarsal skin muscle flap to levator. Due to its retrospective nature some data which would have been interesting is not provided, such as the preoperative blink amplitude to see how much this had been affected by the supramaximal resection.

Reference

Supramaximal levator resection for unilateral congenital ptosis: cosmetic and functional results.
Cruz AAV, Akaishi PMS, Mendonca AKTS, et al.
OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY
2014;30:366-71.

OPHTHALMIC RESEARCH

Effect of voriconazole of vision of healthy volunteers
Reviewed by: Bheemanagouda Patil
Vol 21 No 4
 

Voriconazole is a broad spectrum, triazole antifungal agent used for systemic fungal infections. It has a favourable safety profile and is available in both intravenous and oral forms. The commonest adverse drug reactions with voriconazole are changes in visual perception, namely, increased visual perception (object appearing brighter), subjective blurred vision, changes in colour vision and photophobia (glare or dazzle). This study was to investigate the effects, and their reversibility, of multiple oral doses of voriconazole on a variety of visual tests in healthy male volunteers. Thirty-six volunteers were enrolled in the study who received voriconazole (400mg every 12 hours on day one, then 300mg every 12 hours for 27.5 days). Electroretinography (ERGs) and ophthalmic examinations were carried out at screening and throughout the study period. Fifteen (83.3%) volunteers experienced >1 treatment-related visual adverse events (AEs). No serious AEs were reported. There were reduced scotopic maximal a- and b-wave amplitude, shortened implicit time and decreased oscillatory potential amplitude compared with placebo. Under photopic conditions, the 30-Hz flicker response was significantly reduced too. The study concluded that effects of voriconazole on altered visual perception, ERG, colour vision and static visual field thresholds were non progressive over a treatment period and reversible.

Reference

Effects of multiple doses of voriconazole on the vision of healthy volunteers: a double-blind, placebo-controlled study.
Zrenner E, Tomaszewski K, Hamlin J, et al.
OPHTHALMIC RESEARCH
2014;52(1):43-52

OPHTHALMIC RESEARCH

Fluorescein angiography and OCT in myopic CNV
Reviewed by: Bheemanagouda Patil
Vol 21 No 4
 

Fluorescein angiography (FA) and spectral-domain optical coherence tomography (OCT) are the most common examinations used in the management of anti-VEGF therapy in choroidal neovascularisation (CNV). In comparison to FA, OCT provides a noninvasive evaluation of the macula. Myopic CNV are generally not characterised by excessive amounts of exudation, intraretinal oedema or pigment epithelial detachment. This could limit the role of OCT in the management of myopic CNV. This study was thus aimed to evaluate the agreement between FA and SD-OCT in detecting the activity of myopic CNV during bevacizumab treatment. Thirty-four patients with subfoveal myopic CNV were prospectively enrolled. FA and SD-OCT were done at all visits. At baseline, seven eyes showed leakage on FA with no fluid on OCT and one case showed fluid on OCT and no leakage on FA. At month one, 30/34 cases showed complete concordance. They confirmed the key role of FA in diagnosing myopic CNV and reiterated that OCT may assist FA in the management of myopic CNV.

Reference

Fluorescein angiography and spectral-domain optical coherence tomography for monitoring anti-VEGF therapy in myopic choroidal neovascularisation.
Lacono P, Battaglia Parodi M, Papayannis M, et al.
OPHTHALMIC RESEARCH
2014;52(1):25-31.

OPHTHALMIC RESEARCH

Intravitreal functional plasminogen in branch retinal vein occlusion
Reviewed by: Bheemanagouda Patil
Vol 21 No 4
 

Branch retinal vein occlusion (BRVO) is the second most common vascular disorder of the eye. Intravitreal injections of anti-VEGF agents and corticosteroids have proven efficacy. Posterior vitreous cortex (PVC) adhesion has been shown to support the development of retinal vein occlusion. The induction of a complete posterior vitreous detachment (PVD) is of benefit to BRVO-affected eyes. If intravitreal plasminogen is present in eyes with BRVO, then intravitreally applied tissue Plasminogen activator (t-PA) will activate plasminogen into the active enzyme plasmin, thus facilitating PVD development. In this study, vitreous taps were taken from central vitreous body and plasminogen was functionally determined in a p-nitroanilide reaction after activation with streptokinase (100% of normal, %N = functional plasminogen in pooled normal citrated plasma). Intravitreal functional plasminogen was detected in all analysed samples (n=30) and mean plasminogen activities were found to be 0.97±1.06%N (range: 0.03-3.9%N). The study concluded that intravitreal functional plasminogen is significantly elevated in eyes with BRVO and intravitreal t-PA should be further explored to induce PVD.

Reference

Intravitreal functional plasminigen in eyes with branch retinal vein occlusion.
Bertelmann T, Sekundo W, Strodthoff S, et al.
OPHTHALMIC RESEARCH
2014;52(2):74-80.

OPHTHALMIC RESEARCH

Role of fundus autofluorescence patterns and baseline atrophy area on geographic atrophy progression
Reviewed by: Bheemanagouda Patil
Vol 21 No 4
 

Central geographic atrophy (GA) is one of the morphological sub types of late-stage macular degeneration. The natural course of the disease is characterised by expanding areas of macular atrophy, which cause absolute scotoma. Fundus autofluorescence (FAF) is derived from lipofuscin (LF) in the retinal pigment epithelium (RPE). This study was designed to investigate whether areas of increased autofluorescence (AF) surrounding the atrophic patches are associated with GA enlargement with time. Fifty-four eyes of 35 patients with GA were included in the study. Areas of GA were quantified by RegionFinder software. They concluded that areas with diffuse trickling (median 1.42mm2 / year) and banded patterns (0.81mm2 / year) might have an impact on progression. The group with baseline total atrophic of the eyes <1disc area (DA; median 0.42mm2) had an inverse relation with GA progression compared to the groups with baseline atrophy >1 disc area (p<0.05).

Reference

Geographic atrophy progression in eyes with age-related macular degeneration: role of fundus autofluorescence patterns, fellow eye and baseline atrophy area.
Batioglu F, Oguz YG, Demiral S, Ozmert E.
OPHTHALMIC RESEARCH
2014;52(2):53-9.

OPHTHALMOLOGICA

Detection of antiranibizumab antibodies in exudative AMD
Reviewed by: Sofia Rokerya
Vol 21 No 4
 

In this study the authors aimed to detect immune response to ranibizumab treatment in wet age-related macular degeneration (AMD). An ELISA was employed to quantify the anti-ranibizumab titre which was compared against the control anti-abciximab titre. Titres of anti-ranibizumab antibodies against the variable regions higher than 1:80 and at least four times higher than the control were considered positive. Anti-ranibizumab IgGs were detected in 17.1% of treated patients. No immunoreactivity was noted in the untreated (naïve) patients. For patients with 10 or fewer previous intravitreal injections (IVTs), immunisation against ranibizumab was detected in 11.1% whereas immunisation was observed in 21.7% with more IVTs (p=0.20). No record of uveitis was found in any of the patients included in the study. Factors evoking the immune response are unclear. Subconjunctival reflux may be responsible and patient related factors cannot be excluded. No attempt was made in this study to compare different patient profiles and the time interval between injections was not recorded. Immunity and drug resistance may be one of the key elements prevalent in AMD non-responders of intravitreal ranibizumab therapy, and merits further research.

Reference

Detection of antiranibizumab antibodies among patients with exudative age-related macular degeneration.
Leveziel N, Pelat T, Watier H, et al.
OPHTHALMOLOGICA
2014;232:53-6.

OPHTHALMOLOGICA

Efficacy of intravitreal dexamethasone implant in patients with persistent macular oedema
Reviewed by: Sofia Rokerya
Vol 21 No 4
 

Chronic cystoid macular oedema (CME) can develop secondary to various pathologies such as diabetic maculopathy, retinal vein occlusion and uveitis. It can cause significant visual impairment and macular damage. The therapeutic effect of corticosteroids in CME is through one or more of their properties, i.e. suppression of inflammation, vascular permeability reduction, stabilisation of endothelial tight junctions, and inhibition of synthesis of VEGF and cytokines. The purpose of this study was to examine the effect of dexamethasone drug delivery system (DEX-DDS) in patients with severely recalcitrant CME of average 20 months duration that had a poor or short-term response to other treatment modalities, i.e. intravitreal ranibizumab, intravitreal bevacizumab, intravitreal triamcinolone, periocular triamcinolone injections and / or focal / grid laser. A second goal was to compare treatment results between different CME etiologic groups (branch retinal vein occlusion [BRVO], central retinal vein occlusion [CRVO], uveitis and diabetic macular oedema [DME]). Thirty-seven eyes of 33 patients were included in the study. Eyes were categorised into three groups: diabetic macular oedema (DME, n=14), vein occlusion (n=15) and uveitis (n=7). The mean follow-up was 22±6.9 weeks. Mean age was 61.5±13.1 years (range 26-87). The average duration of CME prior to DEX-DDS injection was 20.3±16 months (range 4-68, median 15.5). Best corrected visual acuity (BCVA) improved from 0.62±0.38 to 0.35±0.29 logMAR (p<0.0001). An improvement in BCVA greater than one ETDRS line was seen in 73% of the eyes (27 of 37). Prior to DEX-DDS injection, 10 of 37 eyes (27%) presented with a BCVA of 20/40 or better. Following DEX-DDS injections, 25 of 37 eyes (68%) achieved a BCVA of 20/40 or better. At the last follow-up visit 11 of 37 eyes (30%) maintained a BCVA of 20/40 or better. A subgroup analysis of the DME, vein occlusion and uveitis groups showed no statistical difference in baseline, best-achieved and last follow-up BCVA between the groups. Central macular thickness (CMT) decreased by 184±246µm from baseline (p<0.0001). In eyes where CME resolved and recurred, the average CME-free period was 11 weeks. The patients had a total of 53 DEX-DDS injections. Thirty-seven eyes received one injection, 12 eyes received two injections, two eyes received three injections and two eyes received four injections. Mean follow-up time after a second DEX-DDS injection was 25.12 weeks. Twenty-three of 37 eyes (62%) demonstrated complete resolution of CME, achieved 6.7±4.4 weeks (median 6.1) after the injection. Nineteen eyes (51%) had CME recurrence 17.3±3.6 (range 12–25) weeks after the injection. Those 19 eyes with CME resolution and a later recurrence had a mean CME-free period of 10.7±5 weeks (range 4–21, median 10.1). The remaining 14 eyes (38%) did not reach a complete resolution of CME, but 13 of those 14 eyes did have a decrease in CME manifested in an average CMT decrease of 181µm or 33% from baseline. The uveitis group showed faster CME resolution (two weeks) and a longer CME-free period (20 weeks). Eighty-six percent of the retreated eyes were in the vein occlusion group, which also showed an overall less favourable response. This study is limited by a small cohort and its retrospective nature.

Reference

Intravitreal dexamethasone implant in patients with persistent macular oedema of variable aetiologies.
Sorkin N, Loewenstein A, Habot-Wilner Z, Goldstein M.
OPHTHALMOLOGICA
2014;232:83-91.

OPHTHALMOLOGICA

Thrombophilia in patients with retinal vein occlusion
Reviewed by: Sofia Rokerya
Vol 21 No 4
 

The authors present a retrospective study of the prevalence of thrombophilia in patients with retinal vein occlusion. The study cohort included 88 patients with central retinal vein occlusion (CRVO), 51 patients with branch retinal vein occlusion (BRVO) and 40 controls. Patients were screened for factor VIII, fibrinogen, antithrombin III, protein C, protein S, homocysteine, activated protein C (APC) resistance, ACA, factor V Leiden, prothrombin G20210A and methylenetetrahydrofolate reductase (MTHFR) C677T mutation. The most common cardiovascular risk factors were hypertension (65.8%) and prior thrombosis at any location (25%) amongst CRVO patients as well as hypertension (72.5%) and smoking (20%) amongst BRVO patients. Mean fibrinogen levels were significantly higher in all patient groups than amongst controls (CRVO: p=0.005; BRVO: p=0.004). Elevated fibrinogen levels (>4.5g/l) were significantly more frequent in the CRVO group compared to controls (p=0.037). This was not the case for the BRVO group (p=0.072). High fibrinogen levels may create hypercoagulable states by increasing blood viscosity, red blood cell aggregation, velocity of platelet aggregation and platelet reactivity. They contribute to atherosclerotic plaque growth and in vitro stabilise fibrin clots. Persistently high levels of fibrinogen might constitute an independent risk factor for RVO. However, further prospective trials to assess the potential link between elevated plasma fibrinogen and RVO have been suggested. Eight of 86 CRVO patients, three of 44 BRVO patients and none of the 39 controls were positive for ACA. Thirty of 82 CRVO patients, 23 of 43 BRVO patients and 20 of 31 controls were methylenetetrahydrofolate reductase MTHFR heterozygotes. Eleven of 82 CRVO patients, 8 of 43 BRVO patients and none of the controls were MTHFR homozygotes. There was a significantly higher rate of homozygous MTHFR mutations in the CRVO and the BRVO group, each compared to controls (CRVO: p=0.032; BRVO: p=0.011). The authors suggest elevated fibrinogen levels, ACA and the homozygous MTHFR C677T mutation as potential risk factors for CRVO / BRVO

Reference

Thrombophilia in patients with retinal vein occlusion: a retrospective analysis.
Risse F, Frank RD, Weinberger AWA.
OPHTHALMOLOGICA
2014;232:46-52.

ORBIT

The presentation of natural killer / T cell lymphoma to the oculoplastic surgeon
Reviewed by: Konal Saha
Vol 21 No 4
 

The authors present three cases of periorbital extranodal natural killer / T cell lymphoma (ENKL). Ages were 20, 45 and 55. All of these patients presented with painless eyelid swelling and a history of sinus disease. One patient had persistent bilateral panuveitis, two had extraocular muscle involvement. Initial biopsies were negative in two of the patients with repeat biopsy confirming lymphoma. The patients died at five, nine and 35 months after diagnosis despite treatment with radiotherapy and chemotherapy. The article highlights the rare presentation of ENKL to the ophthalmologist. An index of suspicion should be maintained in atypical cases of ‘orbital cellulitis’.

Reference

Series of extranodal natural killer/T cell lymphoma, nasal type, with periorbital involvement.
Termote K, Dierickxx D, Verhoef G, et al.
ORBIT
2014:33(4);245-51.

Cataract and Refractive

Anterior and posterior capsular opacification with the Tecnis ZCBOO and AcrySof SA60AT IOL
Reviewed by: Jonathan Chan
Vol 21 No 3
 

This a randomised, controlled, prospective and double-blind study comparing the anterior capsular opacification (ACO) and posterior capsular opacification (PCO) outcomes with two types of single-piece hydrophobic acrylic intraocular lenses (IOL), and AcrySof SA60AT – Group A, and Tecnis ZCBOO – Group B. A total of 148 eyes of 74 patients were recruited in the study between the age of 61-80 years of age with bilateral senile cataracts. Patients were recruited between the period of October 2009 and September 2010 at the Hospital of St. John of God (Vienna). Each patient underwent cataract surgery with implantation of an AcrySof SA60AT Group A in one eye and Tecnis ZCB00 Group B in the fellow eye by the same experienced surgeon. The lens allocation to the first or second operated eye followed a randomised process. All patients were followed up for a total of 12-months postoperatively and the PCO level was evaluated with the evaluation of posterior capsular opacification software, whereas the level of ACO and capsular retraction was evaluated and graded subjectively by the surgeons in the study. The mean PCO score was 0.1±0.17 and 0.21±0.89 in Group A and B respectively, with no statistically significant differences between the groups (p=0.47). No significant correlation was found between the PCO scores in Groups A and B (p=0.17). Regarding ACO, it was found in 15 eyes (20.3%) and two eyes (2.7%) in Groups A and B respectively (p=0.37). Anterior capsular phimosis was found in 13 eyes (17.6%) in the AcrySof SA60AT group. The incidence of glistenings was also found to only be in Group A implanted with AcrySof IOLs; the phenomenon was observed in 66.2%. The authors concluded that there were similar low rates of PCO one year after cataract surgery. It appears to be a difference in the anterior capsular opacification behaviour between the IOL models; the AcrySof SA60AT has a high incidence of ACON capsular phimosis as above. The authors suggest that the high incidence of the ACO could be related to the design of the square edge optic with exclusion of the optic-haptic junction in the Acrysof SA60AT IOL, whereas with the Tecnis IOL the square edge is continuous (360°). The high incidence of capsular phimosis suggests this could be related to the configuration of the surfaces of the IOL that may play a role in the trend to have a more significant capsular phimosis in the Acrysof group. The authors suggest this could also be related to the haptic angulation, whereas in the Tecnis group there is a biconvex IOL with aspheric anterior surface and haptic offset for three points of fixation. In the Acrysof group it is a biconvex lens with haptic angulation of 0.

Reference

Anterior and posterior capsular opacification with the Tecnis ZCBOO and AcrySof SA60AT IOL: a randomised intraindividual comparison (CR).
Kahraman G, Schrittwieser H, Walch M, et al.
BRITISH JOURNAL OF OPHTHALMOLOGY
2014;98:905-9.

Cataract and Refractive

Intraoperative floppy iris syndrome and prevalence of intraoperative complications
Reviewed by: Efrosini Papagiannuli
Vol 21 No 3
 

Alpha-blockers (particularly of the selective type) are known to be associated with intraoperative floppy iris (IFIS) and poor dilation, which can present in various severities during cataract surgery and need to be recognised in order to avoid intraoperative complications. Methods used to overcome these include the use of Healon 5, iris retractors, pupil expansion rings and topical atropine. In this multicentre, retrospective study the authors assessed the prevalence of untoward events during cataract surgery in patients with IFIS and / or the use of pupillary expansion devices. Data from 4923 eyes were collected looking at the use of a-blockers, IFIS and complications like iris trauma, iris prolapse, posterior or anterior capsular tear, intraoperative vitreous prolapse and the use of pupillary expansion devices. A total of 1254 eyes (25.5%) were on alpha-blockers preoperatively and of these, 428 eyes (34.1%) had IFIS. Of the remaining 3663 eyes not on alpha-blockers, 141 eyes developed IFIS, bringing the total IFIS eyes to 569. Therefore 75.2% (428/569) of IFIS eyes were on alpha-blockers perioperatively. It is interesting to note that a large proportion of IFIS eyes were on non-selective alpha-blockers (188/627 eyes versus 229/587 eyes on selective alpha-blockers and 11/40 eyes on both). Of the IFIS eyes (569) 21.97% developed intraoperative complications, with 15.1% having one complication and 7% developing more than one complication. The corresponding figures of non-IFIS eyes were 7.6% total complications, with 4.5% having one complication and 3% more than one complication. A total of 430/4923 eyes (8.7%) had a pupillary expansion device used during surgery, of which 186 eyes (43.3%) had IFIS. Interestingly pupillary expansion devices were used in eyes on selective alpha-blockers 2.5 times more often than in IFIS eyes on non-selective alpha-blockers. The authors conclude that patients on alpha-blockers are at increased risk of IFIS, however, they also demonstrated that non-selective alpha-blockers contribute to a much higher rate of IFIS (43.9%) than previously reported. They are aware of the study limitations secondary to selection bias (predominantly male patients), its retrospective nature, some missing data and possible mis-classifications / under-reporting due to the lack of a standard definition for IFIS. Another limiting factor that is pointed out is that only mechanical pupillary expansion devices were captured and therefore pharmacological means of pupillary expansion may have been missed out, which in part may explain the low utilisation.

Reference

Intraoperative floppy iris syndrome and prevalence of intraoperative complications: results from ophthalmic surgery outcomes database.
Vollman DE, Gonzalez-Gonzalez LA, Chomsky A, et al.
AMERICAN JOURNAL OF OPHTHALMOLOGY
2014;157:1130-5.

Cataract and Refractive

LASEK vs. epi-LASIK for myopia: meta-analysis
Reviewed by: Anjali Gupta
Vol 21 No 3
 

Previous studies have produced inconsistent conclusions on the relative benefits between LASEK vs. Epi-LASIK. LASEK uses 20% alcohol to separate an epithelial flap from the Bowman membrane. After ablation, the epithelial flap is repositioned onto the cornea. Epi-LASIK creates the epithelial flap using a microkeratome-like instrument, the epikeratome. Theoretically, as it preserves the basement membrane and avoids the use of chemical agents, it offers faster epithelium healing and less postoperative pain than LASEK. This meta-analysis consisting of three randomised control trials (RCTs) and three non-randomised cohort studies compared differences in safety, efficacy, predictability, epithelial healing time and corneal haze formation between LASEK and Epi-LASIK. The meta-analysis included 517 eyes from six studies with myopia ranging from 0 to -9.00D. No significant differences were found in the proportion of eyes with uncorrected visual acuity (VA) of 6/6 or better, mean postoperative uncorrected VA, healing time of corneal epithelium, final proportion of eyes losing two or more lines of best spectacle corrected VA and corneal haze levels. The authors concluded that although this meta-analysis demonstrated similar safety and efficacy between LASEK and Epi-LASIK, more data is required to detect the potential differences between the two procedures.

Reference

Laser-assisted sub epithelial keratectomy versus epipolis laser in situ keratomileusis for myopia: a meta-analysis of clinical outcomes.
Wen D, Huang J, Li X, et al.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2014;42:323-33.

Cataract and Refractive

Visual acuity after cataract surgery in AMD patients
Reviewed by: Brian Ang
Vol 21 No 3
 

The data from this study are obtained from the Age-Related Eye Disease Study (AREDS) 2 and analysed to evaluate if cataract surgery benefits patients with concurrent age-related macular degeneration (AMD). The AREDS 2 was a five year, prospective, multi-centre randomised controlled trial of nutritional supplements for the treatment of AMD. Of the 8406 eyes from 4203 study participants, 1232 eyes of 793 patients underwent cataract surgery during the study. When adjusted for age, gender and severity of cataract, eyes with mild AMD gained 11.2 letters, eyes with moderate AMD gained 11.1 letters, eyes with severe AMD gained 8.7 letters, and eyes with advanced AMD gained 6.8 letters. This study was not designed for this purpose and thus has several shortcomings, including lack of uniform postoperative follow-up periods. Nevertheless, the large patient numbers and longitudinal follow-up are major strengths of the study. The study confirms that cataract surgery can improve the visual acuity significantly in AMD patients, whether mild, moderate, severe or advanced. AMD patients should not be discouraged from undergoing cataract surgery on account of their guarded prognosis as visual benefits may be achieved.

Reference

Visual acuity after cataract surgery in patients with age-related macular degeneration.
Age-Related Eye Disease Study 2 Research Group.
OPHTHALMOLOGY
2014;121:1229-36.

Cornea and External Eye Disease

Adjunctive topical 5-FU vs. MMC for surgically excised, localised OSSN
Reviewed by: Anjali Gupta
Vol 21 No 3
 

Ocular surface squamous neoplasia (OSSN) comprises a range of dysplasia including corneal-conjunctival intraepithelial neoplasia and invasive squamous cell carcinoma. The traditional treatment for localised non-invasive OSSN has been surgical excision with or without intraoperative cryotherapy. Postoperative adjunctive topical chemotherapy significantly reduces the rate of recurrence. This paper presented a long-term follow-up of two prospective non-comparative interventional case series examining recurrence and side-effect rates in patients receiving 5-FU (fluorouracil) or mitomycin C (MMC) as adjuvants to surgical excision of localised OSSN. Eighty-nine eyes were included in the 5-FU group and 64 eyes were included in the MMC group. All patients underwent complete superficial dissection of the lesion with a 2mm margin. All lesions in the 5-FU group had cryotherapy applied intraoperatively, however, cryotherapy was not available in 18.7% of cases in the MMC arm. Median follow-up was 33.6 months in the 5-FU arm and 57.9 months in the MMC arm. There were no recurrences in the MMC arm and one recurrence in the 5-FU arm. This case of recurrence was in an incompletely excised CIN III lesion with an incomplete course of adjuvant 5-FU therapy. Overall, side-effects were encountered in 69% of 5-FU cases compared with 41% of MMC cases. Sixty-two percent of 5-FU cases experienced lid toxicity vs. 0% of MMC cases. No 5-FU cases experienced allergy vs. 28% of MMC cases. Ten percent of patients in the 5-FU group developed epiphora, compared with 17% in the MMC group. The authors concluded that recurrence is rare when adjuvant 5-FU or MMC is used in surgically excised localised OSSN and although side-effects are common, the majority are transient and rarely limit compliance.

Reference

Long-term outcomes after adjunctive topical 5-fluorouracil or mitomycin C for the treatment of surgically excised, localised ocular surface squamous neoplasia.
Bahrami B, Greenwell T, Muecke S.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2014;42:317-22.

Cornea and External Eye Disease

Effect of preservative free fluoroquinolones on human corneal epithelial cells in vitro
Reviewed by: Bheemanagouda Patil
Vol 21 No 3
 

Fluoroquinolones, including second generation (ofloxacin and ciprofloxacin), third generation (levofloxacin and tosufloxacin) and fourth generation (gatifloxacin and moxifloxacin), are a group of bactericidal agents used to treat multiple ocular infections. The third and fourth generation fluoroquinolones have enhanced Gram-positive activity when compared to the earlier ones. However, long-term use of these can affect human corneal epithelial cells. This study looks at the biologic and toxic effects of these diverse generation fluoroquinolones on cultured human corneal epithelial cells. Amongst those studied were ofloxacin, levofloxacin, tosufloxacin, moxifloxacin and gatifloxacin. MTT-based calorimetric assay, lactate dehydrogenase (LDH) assay and scratch wound test were performed. Corneal epithelial cell morphologies were examined by performing inverted light microscopy and transmission electron microscopy. The study found that the fourth generation fluoroquinolones (moxifloxacin and gatifloxacin) induced greater toxic effect to the corneal epithelial cells when compared to previous generation fluoroquinolones.

Reference

Effect of fluoroquinolone eye solutions without preservatives on human corneal epithelial cells in vitro.
Oum BS, Kim M, Lee JS, Park YM.
OPHTHALMIC RESEARCH
2014;51(4):216-23.

Cornea and External Eye Disease

Inhibiting high-risk corneal allografts
Reviewed by: Graham Wallace
Vol 21 No 3
 

The cornea is an immune privileged site and as such corneal transplants are very successful. However, in situations where this privilege is lost the failure rises substantially. To combat rejection inhibition of the immune responses depends on steroids and other immunosuppressive drugs, which are not always successful and sometimes have severe side-effects. In this paper the T cell receptor immunoglobulin and mucin domain (Tim) family member Tim1 was investigated. Tim1 is not expressed in naive CD4+ but is upregulated on the cell surface when activated, particularly on Th2 cells that are normally involved in allergic responses. To induce a high-risk transplant Balb/c mice were transplanted with corneas from C57BL/6 mice, which have different transplantation antigens and so will be recognised as foreign. Transplanted mice were either treated with RMT1-10, an anti-Tim1 monoclonal antibody or an isotype control. In RMT1-10 treated mice the numbers of effector immune cells were significantly decreased while T regulatory cells were significantly increased in the spleen, and allograft survival and corneal opacity were significantly increased. In vitro studies showed reduced expression of both IFN-Y and IL-4 in splenic CD4+ T cells from RMT1-10 treated animals. By comparison, expression of TGF-ß1, an anti-inflammatory cytokine was increased. Finally, RMT1-10 treated cells inhibited the delayed-type hypersensitivity in recipient mice, a model which supports a regulatory effect. The results suggest that inhibition of Tim1 can increase the regulatory arm of the immune response and decrease the inflammatory response, leading to increased allograft survival. The potential for such treatment in humans is of interest as unlike many diseases the timing of graft delivery and rejection is known and therefore delivery of inhibitory molecules easily determined.

Reference

Tim-1 blockade with RMT1-10 increases T regulatory cells and prolongs the survival of high-risk corneal allografts in mice.
Tan X, Jie Y, Zhang Y, et al.
EXPERIMENTAL EYE RESEARCH
2014;122(5):86-93.

Cornea and External Eye Disease

Neurotrophic keratitis
Reviewed by: Sofia Rokerya
Vol 21 No 3
 

The authors present an overview of the aetiology, diagnosis, current and future management options of neurotrophic keratitis. This is a degenerative corneal disease that occurs following the compromise of trigeminal innervation, leading to hypoesthesia
and / or anaesthesia. The aetiology is variable and includes herpetic infections, chemical burns, contact lens wear, lasik, keratoplasty, topical anaesthetics, glaucoma medications, surgery and pathology involving the trigeminal nerve, diabetes, and hypovitaminosis A. It may be associated with the use of neuroleptics, antipsychotics, anti-histamines, etc. Mackie’s classification is used to grade the severity of the condition. Clinically the condition may vary from punctuate epithelial erosion to corneal ulceration and may result in stromal melt and silent perforation of the globe. Management options comprise of lubricants without preservatives, punctual plugs, antibiotics for infected ulcers, bandage contact lenses, tarsorraphy and botulinum toxin induced ptosis to help healing in refractory cases. The use of steroids remains controversial as although it may improve inflammation, it is associated with increased risk of perforation. Surgical options include conjunctival flaps, amniotic membrane grafts, cynoacrylate glue for perforating ulcers and keratoplasty. The newer medical therapies include autologous serum eye drops, umbilical cord serum eye drops. Some studies are proposing that the topical use of substance P (SP) insulin like growth factor -1 (IGF-1) and nerve growth factor (NGF) may play a key role in potential future treatment of neurotrophic keratitis.

Reference

Neurotrophic keratitis.
Semeraro F, Forbice E, Romano V, et al.
OPHTHALMOLOGICA
2014;231:191-7.

Glaucoma

Beliefs and adherence to glaucoma treatment
Reviewed by: Lorraine North
Vol 21 No 3
 

The aim of the study was to determine adherence rates and beliefs about glaucoma and its treatment in white Americans, African Americans, white Australians and Singaporeans of Chinese descent. A cross-sectional study of 475 glaucoma patients using topical eye drops for at least six months was carried out. Adherence was assessed using an adaptation of the self-report measure the Reported Adherence to Medication validated questionnaire. The authors found significant differences in the age, duration of treatment for glaucoma and level of education between the groups. Overall they found that self-reported rates were fairly high for all groups. For example, Singaporeans reported significantly lower understanding of their glaucoma than any other group and also believed less strongly in the ability of their eye drops to control glaucoma compared with all the other groups. African Americans were significantly more concerned about their glaucoma than any other group and also reported to be more effected emotionally by glaucoma. Australians experienced significantly more symptoms from glaucoma and believed that glaucoma had a greater impact on their life. This study revealed significant differences in self-reported adherence between glaucoma patients from diverse cultures.

Reference

Beliefs and adherence to glaucoma treatment: a comparison of patients from diverse cultures.
Rees G, Chong X-L, Cheung C, et al.
JOURNAL OF GLAUCOMA
2014;23(5):293-8.

Glaucoma

Bleb-related infection after mitomycin C trabeculectomy
Reviewed by: Brian Ang
Vol 21 No 3
 

The authors report on the results of the Collaborative Bleb-related Incidence and Treatment Study (CBIITS), which was a five year multi-centre prospective study designed to investigate the incidence of bleb-related infection following filtering surgery with mitomycin C. In this study, bleb-related infection was defined as an infection that: (1) followed trabeculectomy or phaco-trabeculectomy, (2) occurred four weeks post-surgery, and (3) demonstrates clinical signs of infection related to a filtering bleb. Patients were followed up every six months for five years. A total of 1098 eyes (1098 patients) were suitable for inclusion in the study, with 824 eyes completing the five year follow-up or reached the end point of developing bleb-related infection. While 916 eyes underwent trabeculectomy alone, 182 eyes had phaco-trabeculectomy. Of these eyes, 21 developed bleb-related infection, occurring 27.3±15.9 months after surgery. The cumulative incidence of all bleb-related infection was 2.2±0.5% over the five year follow-up, while the cumulative incidence of bleb-related endophthalmitis was 1.1±0.3%. There was no difference between trabeculectomy alone or phaco-trabeculectomy, and no difference between fornix-based and limbal-based surgery. The main risk factor for infection was bleb leak (cumulative incidence 7.9±3.1%). This is the largest study to date evaluating the incidence of bleb-related infection following mitomycin C trabeculectomy. It confirms not only the relative safety of using mitomycin-C, but also the importance of long-term monitoring for bleb leak after filtering surgery.

Reference

The 5-year incidence of bleb-related infection and its risk factors after filtering surgeries with adjunctive mitomycin C.
Yamamoto T, Sawada A, Mayama C, et al.
OPHTHALMOLOGY
2014;121:1001-6.

Glaucoma

Brimonidine day and night time IOP
Reviewed by: Lorraine North
Vol 21 No 3
 

The authors describe a randomised double masked study of 29 participants with ocular hypertension (OHT) who either self-administered 0.2% brimonidine or placebo three times daily for six weeks. Patients were seen during day time and night time visits and had measurements of aqueous flow, outflow facility, episcleral venous pressure and seated and supine IOP. Uveoscleral outflow was calculated mathematically. The authors found that the effect of brimonidine was partially dependent on both the body position of the subject during IOP measurement and the time between the last dose. They concluded that in patients with OHT brimonidine treatment for six weeks significantly reduced seated IOP during the day, however, the study had several limitations due to techniques available such as for aqueous humour dynamics and calculation uveoscleral outflow.

Reference

Daytime and night-time effects of brimonidine on IOP and aqueous humor dynamics in participants with ocular hypertension.
Fan S, Agrawal A, Gulati V, et al.
JOURNAL OF GLAUCOMA
2014;23(5):276-81.

Glaucoma

Comparison of false-negative responses in glaucoma patients and normal observers
Reviewed by: Lorraine North
Vol 21 No 3
 

The authors compared false negative rates for full threshold (FULL) and Swedish Interactive Threshold Algorithm (SITA) standard automated perimetry in healthy control subjects and glaucoma patients. Twenty-four subjects underwent visual field testing of one eye five times within six weeks (19 glaucoma and five controls) with 24-2 FULL and SITA standard perimetry. They obtained false negative response procedures that presented stimuli at nine dB greater than a previously determined threshold value at specific locations (FULL) and up to 20 dB greater than the threshold for SITA. Their results showed that the percentage of false negatives was almost twice as high with FULL testing compared with the two SITA analyses. The authors felt that this may be related to the SITA method of testing for false negatives in relatively normal areas as opposed to any location (even if it has low sensitivity) with FULL due also to high variability in damaged areas or pathologic variations.

Reference

A comparison of false-negative responses for full threshold and SITA standard perimetry in glaucoma patients and normal observers.
Johnson CA, Sherman K, Dolye C, Wall M.
JOURNAL OF GLAUCOMA
2014;23(5):288-92.

Glaucoma

Hyphema after trabeculectomy with MMC
Reviewed by: Lorraine North
Vol 21 No 3
 

The authors retrospectively reviewed the medical records of consecutive patients with glaucoma who underwent trabeculectomy with mitomycin C between June 2005 and December 2010 to determine the risk factors for hyphema after surgery. Of the 420 patients, 104 (24.8%) had hyphema. Their study identified neovascular glaucoma and anticoagulant or antiplatelet medication at trabeculectomy as being significant risk factors, subgroup analysis demonstrated that neovascularisation in the anterior chamber angle and anticoagulant or platelet medication were risk factors for postoperative hyphema whereas preoperative injection of bevacizumab reduced the likelihood.

Reference

Risk factors for hyphema after trabeculectomy with
mitomycin C.
Kojima S, Inatani M, Shobayashi K, et al.
JOURNAL OF GLAUCOMA
2014;23(5):307-11.

Neuro-Ophthalmology

Non-arteritic anterior ischaemic optic neuropathy in the Asian population
Reviewed by: Claire Howard
Vol 21 No 3
 

This article provides an evaluation of changes in visual function associated with non-arteritic anterior ischaemic optic neuropathy (NAION) among Korean patients. Visual changes were identified as a reduction in visual acuity by three Snellen lines or a deterioration of visual field. Medical records were reviewed retrospectively to provide the data. In total 50 eyes from 43 patients satisfied all the inclusion criteria. Overall, the prognosis of visual acuity in association with NAION was worse in Korean patients than in western studies. This difference may be attributed to racial differences. This study does show an improved prognosis of visual field defects but this may be accounted to the different methods used to evaluate visual fields (Goldmann perimetry in this study). The grid method was used in this review to calculate changes in visual field defects. Visual acuity and visual field defects showed improvement in approximately 30% of eyes and deterioration in approximately 10%. With visual acuity the largest changes occurred during the first month after presentation. The initial visual field defect was most likely to improve between the one and three month follow-up visit. In summary, this is reported as the first known study looking at the relationship between race and the prognosis of visual acuity in NAION. Although this has some clinically relevant elements the results are limited by a
small sample size and its retrospective design, meaning further studies are required in this area for a direct relationship to be confirmed.

Reference

Changes in visual function over time in Koreans with non-arteritic anterior ischaemic optic neuropathy.
Wong Chang J, Choi J, Suk Yu Y, Kim SJ.
NEURO-OPHTHALMOLOGY
2014;38(2):62-8.

Neuro-Ophthalmology

Reported cases of hemifield slide phenomenon
Reviewed by: Claire Howard
Vol 21 No 3
 

This article reports three cases of hemifield slide, a phenomenon whereby there is an inability to stabilise and fuse visual hemifields. It occurs with heteronymous visual field loss and is thought to result from the loss of corresponding retinal points. The shift can be a horizontal or vertical binocular dissociation of visual fields and can lead to diplopia without evidence of a muscle paresis. One of the cases discussed is a case of binasal hemianopia in whom symptoms improved with expansion of the visual fields. The other two cases were of bitemporal field defects causing hemifield slide. Both these patients underwent strabismus surgery, one of whom had adjustable suture surgery, who described changes in her visual field before, during and after the adjustment which were classic for hemifield slide. The three patients reported have described intermittent diplopia as a symptom (two cases) and missing a central strip in the binocular visual field (remaining case). Visual field improvement resolved the hemifield slide in the patients reported. This article highlights the symptoms and treatment options for this small patient group, reporting that symptoms can be difficult to correct, especially where the visual field defect persists.

Reference

Hemifield slide phenomenon as a result of heteronymous hemianopia.
Peragallo JH, Bialer OY, Pineles SL, Newman NJ.
NEURO-OPHTHALMOLOGY
2014;38(2):82-7.

Ocular Pathology and Oncology

Case series of posterior scleritis
Reviewed by: Saruban Pasu
Vol 21 No 3
 

This report aimed to facilitate the correct diagnosis of posterior scleritis, a condition which is usually overlooked or misdiagnosed. Electronic health records of 31 patients with posterior scleritis were analysed and compared to a group with isolated anterior scleritis of any kind. Eighty-four percent of patients with posterior scleritis were female. The mean age of presentation was 44 years. Pain was present in all patients, with most having subacute and unilateral inflammation. Decrease in vision (20/80 or worse at presentation and / or loss of two or more Snellen lines) was documented in 29% of patients with posterior scleritis. Sixty-eight percent had associated anterior scleritis and 26% anterior uveitis at some point during follow-up. Eighty-one percent of cases were idiopathic while psoriatic arthritis, Crohn’s disease, HLA-B27, SLE and TINU were the other associated systemic conditions. Uveitis was more frequently associated in patients younger than 40 years. The mean age of patients with posterior scleritis was lower than those with anterior scleritis. Association with a systemic disease was found more frequently in patients with isolated anterior scleritis than in those with posterior scleritis. The authors comment that visual loss is more frequent than in those with anterior scleritis. They therefore recommend that all scleritis patients should undergo B-Scan ultrasonography so as not to miss any posterior disease. Although not statistically significant, they found that the more painful eyes had a greater chance of a decrease in vision.

Reference

Clinical features and presentation of posterior scleritis: a report of 31 cases.
Gonzalez-Gonzalez LA, Molina-Prat N, Doctor P, et al.
OCULAR IMMUNOLOGY AND INFLAMMATION
2014;22(3);203-7.

Ocular Pathology and Oncology

Vital dyes in ophthalmology
Reviewed by: Khadijah Basheer
Vol 21 No 3
 

This comprehensive review gives an excellent summary of the uses and properties of the different dyes available to aid better visualisation and diagnoses in ophthalmology. The authors clearly display the pharmacological properties, molecular details, osmolarity and indications in clinical ophthalmology of all known and relevant dyes. Various dyes are used today in corneal diseases and each has unique properties that are beneficial for a specific use; for example Rose Bengal to evaluate the protective status of the pre-ocular tear film, fluorescein which indicates increased epithelial permeability and Lissamin green B that stains devitalised cells. In addition dyes have an important role in surgery, particularly cataract and vitreoretinal surgery to enable better visualisation of the anterior capsule and pre-retinal membranes respectively. The authors conclude that the field of vital dyes offers great opportunities for research in ophthalmology and that new and novel dyes need further studies to clarify the safety and optimal indications in ophthalmology.

Reference

Vital dyes in ophthalmology.
Badaro E, Novais EA, Penha FM, et al.
CURRENT EYE RESEARCH
2014;39(7):649-58.

Oculoplastic and Orbit

Does mitomycin C improve success rates in DCR surgery?
Reviewed by: Konal Saha
Vol 21 No 3
 

The authors present a meta-analysis of the use of mitomycin C (MMC) as an adjunct in dacrocystorhinostomy (DCR) surgery. Fifteen randomised control trials were included. There was a degree of heterogeneity in the surgical technique used, however, the MMC is applied to the osteotomy site intraoperatively to reduce the risk of closure. MMC at concentrations between 0.02 and 1.0mg/ml were applied for between two and 30 minutes. There was no statistically significant difference in the outcome of primary endoscopic DCR (three studies) with or without the use of MMC. There was a statistically, and clinically significant difference in the outcome of primary external DCR. The failure rate was 12.6% in the control group and 6.3% in the MMC group (nine studies). The difference in failure rate of revision endo DCR was also statistically and clinically significant dropping from 30.4% to 13.2% (three studies). The meta analysis suggests there may be a role for MMC in DCR surgery, with the current results favouring its use in primary external DCR and revision endoscopic DCR.

Reference

Meta-analysis of the adjunctive use of mitomycin C in primary and revision, external, and endonasal dacryocystorhinostomy.
Xue K, Mellington FE, Norris J.
ORBIT
2014;33(4):239-44.

Oculoplastic and Orbit

Patient-reported outcomes in oculoplastic surgery
Reviewed by: James Hsuan
Vol 21 No 3
 

This is an important if somewhat difficult to grasp article which tries to formally address the subject of patient-reported outcomes in oculofacial surgery. The authors have conducted an extensive review of the literature searching for instruments (questionnaires) which have been used to assess the success of an intervention from a patient’s perspective. The introduction explains the increasing importance of these measures, not only to prove the efficacy of an intervention, or the superiority of one treatment over another, but also the benefits to the doctor patient relationship and general delivery of care. Despite this, the authors state there is a relative lack of these tools in current practice and in oculofacial research. The paper divides the instruments which have been used into generic measures and those specific to oculoplastic conditions, and lists them in two tables. The generic table also contains the oculoplastic conditions for which each tool has been used, the most common being thyroid eye disease, blepharospasm and ptosis. The disease-specific table lists 32 publications of patient-reported outcome studies, many of which use ad hoc measures which lack repeatability and validity data. The generic tools are better developed but may lack sensitivity to the specific outcome of interest in a particular oculoplastic procedure. The authors have made no attempt to rank each tool in relation to a particular intervention, but the paper is a useful starting point for anyone considering introducing patient-reported outcomes into their practice or conducting research in this area.

Reference

Patient-reported outcomes: comprehensive analysis for the oculofacial clinician.
Ramey NA, Butt Z, Burkat CN, et al.
OPHTHALMIC PLASTIC & RECONSTRUCTIVE SURGERY
2014;30:279-89.

Paediatric Ophthalmology and Strabismology

Binocular training for amblyopia
Reviewed by: Fiona Rowe
Vol 21 No 3
 

The clinical effectiveness of binocular investigation for amblyopia was measured. The authors had previously unsuccessfully treated patients using occlusion and / or surgery. Patients were followed for an average of six months after cessation of treatment. The study included 22 patients with strabismic or anisometropic amblyopia with a mean age of 36.2±20.3 years. They completed an average 14.5 sessions of binocular training over four to six weeks. Random dot kinematograms were presented dichoptically to both eyes. The patient had to identify the direction of motion of targets. Results showed improved visual acuity in all patients and this was maintained after six months. The mean increase in visual acuity was 0.34 logMAR and increased significantly with the number of treatment sessions completed. The age and severity of amblyopia did not predict improved visual acuity. Suppression levels for amblyopia were not reported in this study.

Reference

Binocular training reduces amblyopic visual acuity impairment.
Monsouri B, Singh P, Globa A, Pearson P.
STRABISMUS
2014;22:1-6.

Paediatric Ophthalmology and Strabismology

Brown’s syndrome surgery
Reviewed by: Fiona Rowe
Vol 21 No 3
 

Complications of surgery for Brown syndrome include under correction, extrusion of expanders and training for surgery. The authors introduced a procedure with minimal side-effects, accompanied by the application of the native tendon for superior oblique elongation. This was a prospective pilot study of congenital Brown syndrome. The surgery gives elongation of about 10mm. Fourteen patients (15 eyes) were included aged 3-20 years. Follow-up was 10-16 months duration. The mean preoperative horizontal angle was 4.7±10.4 divergence which reduced to 3.3±8.1 divergence. Mean preoperative vertical angle was 16.2±5.5 hypotropia which reduced to 5.8±3.9. Mean preoperative duction limitation was -7.2±4.5 which reduced to -1.8±1.3. The abnormal head posture improved postoperatively. One patient was under corrected’ 53% had excellent results, 40% acceptable results and 6.7% were under corrected. Clinical success was achieved in 93.3%.

Reference

The results of Brown syndrome surgery with superior oblique split tendon lengthening.
Moghadam AAS, Sharifi M, Heydari S.
STRABISMUS
2014;22:7-12.

Paediatric Ophthalmology and Strabismology

Comparison of photoscreeners
Reviewed by: Fiona Rowe
Vol 21 No 3
 

The purpose of this study was to apply the GoCheckKids, iScreen, PlusoptiX and SPOT to young patients and developmentally challenged patients in a paediatric eye practice. One hundred and eight children were assessed with a mean age of 47 months (9-146). Eleven had developmental delay and / or autism, 11 had constant strabismus and one had nystagmus. Spherical equivalent refractive error ranged from -22 to +6DS. Ten patients had anisometropia of >2D. Twenty-seven children passed all four assessments: nine had intermittent strabismus of 10-30PD. All four instruments were found to yield good screening accuracy and are valuable in identifying treatable vision impairment early enough for amblyopia treatment to be effective. Sensitivity, specificity and inclusive results were: PlusoptiX (83, 86 and 23%), SPOT (80, 85, 4%), iScreen (75, 88 and 13%), iScreen with Delta Center Crescent (92, 88, 0%) and GoCheckKids with Delta Center Crescent (81, 91, 3%).

Reference

Performance of four new photoscreeners on pediatric patients with high risk amblyopia.
Arnold RW, Armitage MD.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:46-52.

Paediatric Ophthalmology and Strabismology

Congenital aniridia clinical features
Reviewed by: Fiona Rowe
Vol 21 No 3
 

In this study the authors investigated the various ocular and systemic features associated with congenital aniridia in Indian eyes (262 eyes of 131 patients). The median age at time of first hospital visit was eight years (one day to 73 years). There were 51% male and 49% female. Ninety-seven percent had bilateral aniridia, one unilateral and one normal. The median visual acuity at presentation was 1.0 logMAR (0.10-2.10). Fifty-six percent had horizontal jerk nystagmus. Corneal involvement was seen in 60%. Phakic lens status was in 94%. Others were pseudophakic or aphakic. Cataract was present in 38.5%, subluxation in 22%, foveal hypoplasia in 88%, vitreous opacities in 16%. A pale disc was present in 13 eyes, hypoplastic in seven eyes. Three had retinal detachment. Glaucoma was present in 36%. Males had higher proportion of associated subluxation. There was no gender preponderance for glaucoma and cataract. The authors conclude that aniridia is commonly associated with other ocular features but systemic associations were notably absent.

Reference

Clinical manifestations of congenital aniridia.
Singh B, Mohamed A, Chaurasia S, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:59-62.

Paediatric Ophthalmology and Strabismology

Conversion to strabismus and amblyopia
Reviewed by: Fiona Rowe
Vol 21 No 3
 

This study was undertaken to evaluate the incidence of true manifest strabismus, the visual acuity at school screening and whether risk of failing screening is different in those discharged at first visit or followed up. The author reviewed 248 children under the age of 30 months who had been diagnosed as pseudo strabismus or no deviation. Initial concern for referral was predominantly suspected esotropia in 133 cases. Eighty-two were discharged at their first screening visit and 166 were given a follow-up appointment. It was found that the incidence of esotropia for those who were initially otherwise normal on the first screening visit is between 2.4 and 3.4%. There is no significant difference in the risk of failing vision screening between the general population and those screened by the orthoptist. Presence of positive family history contributed to the decision to offer follow-up appointments but there was no significant difference between those discharged or followed for those that later developed esotropia.

Reference

Development of manifest strabismus and reduced visual acuity following initial normal orthoptic examination / pseudo strabismus under the age of 30 months.
Garretty T.
STRABISMUS
2014;22:26-31.

Paediatric Ophthalmology and Strabismology

IOOA and DVD surgery
Reviewed by: Fiona Rowe
Vol 21 No 3
 

The authors report the results of bilateral modified inferior oblique (IO) transposition considering the equator in seven patients with infantile strabismus syndrome with  inferior oblique overaction (IOOA) and dissociated vertical deviation (DVD). Mean age was 4.5 years (2-7) and mean follow-up was 6.3 months. Mean distance between the lateral border of the inferior rectus insertion and equator was 5.6mm (4.5-6.5). Nine patients had IO transposed onto the equator and five were placed 1mm anterior to the equator. Preoperatively all had IOOA of ≥1.5. Postoperatively IOOA was <1+ in all cases. Six patients had DVD within 1PD and only one patient had DVD of 5PD. No cases of anti-elevation syndrome were found postoperatively. Therefore the authors propose that good surgical results are achieved with this procedure although they acknowledge the small sample size.

Reference

Modified inferior oblique transposition considering the equator for primary inferior oblique overaction (IOOA) associated with dissociated vertical deviation (DVD).
Yoo EJ, Kim SH.
STRABISMUS
2014;22:13-7.

Paediatric Ophthalmology and Strabismology

IR recession and prevention of lower lid retraction
Reviewed by: Fiona Rowe
Vol 21 No 3
 

The authors report the efficacy in preventing lower eyelid retraction and long-term results of a new technique of inferior rectus recession for vertical strabismus. The results for 35 patients were compared with 22 patients having conventional inferior rectus recession. Inferior rectus recession was the sole operation for 26 cases of the study group. Nine also required contralateral inferior oblique recession. In the study group the mean age of onset of strabismus was 27.7±8.6 years, 80% had a satisfactory outcome and 20% were undercorrected. In the control group the mean onset of strabismus was 25.7±8.6 years, 78% had a satisfactory outcome and 22% were undercorrected. Lower eyelid retraction was significantly less for the study group than controls. The new technique recesses the deeper fibre layer including approximately 90% of inferior rectus muscle thickness that is present with preservation of anterior ciliary arteries. This avoids lower lid retraction. Otherwise there were no significant differences between groups for improvement in deviation and success ratios.

Reference

Long-term results of deeper muscle fibre recession of an inferior rectus operation.
Gokyigit B, Akar S, Kaynak P, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:17-26.

Paediatric Ophthalmology and Strabismology

LR/SR surgery for high myopia strabismus
Reviewed by: Fiona Rowe
Vol 21 No 3
 

The authors evaluated the outcomes of a surgical procedure involving the muscle union of the superior rectus and lateral rectus muscles with and without medial rectus recession and the anatomic changes before and after surgery in 35 eyes of 20 patients. Surgery included the union of muscle bellies with suture 14-15mm posterior to the muscle insertions. Muscles were not split and were not attached to the sclera. Mean age at strabismus onset was 34.8 years ±3.1. Fifteen had bilateral high axial myopia and five were unilateral. Axial lengths were 26-36mm (mean 30.6±2.8). Mean refraction was -19.01±3.1D. Significant improvement was found in which the angle remained stable over four years follow-up. Nine eyes were cured with superior rectus / lateral rectus surgery alone. Indication for medial rectus recession was presence of positive forced duction test and tight medial rectus and the time of surgery. Mean preoperative angle of globe dislocation of 178 degrees which reduced to 101 degrees. Horizontal angle decreased from 58.6 to 6.8PD and vertical angle decreased from 12.5 to 3.3PD. Ocular movements were significantly increased postoperatively. The authors concluded this to be an effective procedure.

Reference

Surgical procedure joining the lateral rectus and superior rectus muscles with or without medial rectus recession for the treatment of strabismus associated with high myopia.
Akar S, Gokyigit B, Aribal E, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:53-8.

Paediatric Ophthalmology and Strabismology

Measuring IPD with PlusoptiX
Reviewed by: Fiona Rowe
Vol 21 No 3
 

The authors evaluated the accuracy of the PlusoptiX A04 for measuring pupillary distance as compared to measurements taken by a trained optician. This retrospective review included 256 children who had undilated PA04 screening and had pupil distance measurement done by the optician using the L8 digital pupil distance meter. Children were aged 1-16 years: 142 ortho, 97 esotropia and 17 exotropia. The mean absolute difference for the two measures for the entire cohort was 0.3mm (SD-3.12). There was good agreement of 0.76 correlation coefficient. Agreement was less for strabismic patients at 0.8mm for esotropia. The range of measurements provided by PA04 was wider than acceptable and therefore the authors propose that this should not be preferred as a first line method.

Reference

The accuracy of the PlusoptiX for measuring pupillary distance.
Singman E, Matta N, Tian J, Silbert D.
STRABISMUS
2014;22:21-5.

Paediatric Ophthalmology and Strabismology

Melphalon treatment of retinoblastoma
Reviewed by: Fiona Rowe
Vol 21 No 3
 

The purpose of this study was to report the authors’ experience with superselective ophthalmic artery infusion of Melphalon (SOAIM) for the treatment of five cases of unilateral sporadic retinoblastoma involving the macula. Standard therapy included a cycle of three infusions at an interval of three to four weeks each. Mean follow-up was 19 months (10-34). Globally SOAIM was well tolerated without major side-effects. Local adverse events were transient such as rash, haemorrhage and ptosis. All eyes were treated by transpupillary thermotherapy during or after the SOAIM. No enucleations were required and all patients remained alive and free of metastatic disease. The authors conclude SOAIM may be a potentially useful approach to treatment of retinoblastoma allowing the salvage of residual sight and low rate of complications. Tumour regression occurred in all cases.

Reference

Successful treatment of macular retinoblastoma with superselective ophthalmic artery infusion of melphalon.
Hadjistilianou T, Coriolani G, Bracco S, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:32-8.

Paediatric Ophthalmology and Strabismology

Review of IDeX surgical outcome measures
Reviewed by: Fiona Rowe
Vol 21 No 3
 

The authors aimed to evaluate whether or not there exists standardisation of outcome measures amongst studies in the literature reporting results of surgery for intermittent exotropia. A 10 year literature review was conducted from 2002-2012 with extraction of English language papers. Fifty-six studies met the inclusion criteria: 24 prospective and 32 retrospective. The reported outcome measures were classified into four categories: postoperative alignment, sensory status, control measures and long-term changes. Eighty-nine percent of studies used postoperative alignment as a measure of success. There were eleven different definitions of what successful alignment meant. Ten percent used sensory status, distance and near stereoacuity as measures of success. Twenty-one percent reported success as a distance angle between 0-10PD; 14% as <5PD esotropia or <10PD exotropia. The time point for reporting outcomes was two months to two years postoperative. Seven percent measured quality of life and patient reported outcome measures. The authors recommend four outcome measures for future studies including alignment, near stereoacuity, control score and quality of life score.

Reference

Standardising reported outcomes of surgery for intermittent exotropia – a systematic literature review.
Chiu AKC, Din N, Ali N.
STRABISMUS
2014;22:32-6.

Paediatric Ophthalmology and Strabismology

Use of white coat and greetings
Reviewed by: Fiona Rowe
Vol 21 No 3
 

This study was undertaken to characterise the practice patterns of paediatric ophthalmologists regarding their use of white coats and salutations in outpatient visits. A questionnaire was sent to American Association for Pediatric Ophthalmology and Strabismus (AAPOS) members with a response rate of 47.8% (n=606). Seven were excluded leaving 574 physicians and 25 fellow responses. Seventy-four percent did not routinely wear a white coat. Forty-six percent addressed parents as Mum / Dad, 33% by surname, 5% by first name and 16% by various combinations. Fellows did not address parents by first name alone. The results show that physician use of white coats runs contrary to patient and parent preferences. Practice patterns appear to concur with previously reported parental greeting preferences.

Reference

Physician use of white coats in pediatric ophthalmology.
deBenedictis CN, Liu GT, Nelson LB, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2014;51:13-6.

Retina, Vitreous and Uvea

Akimba mice, a model of human diabetic retinopathy
Reviewed by: Graham Wallace
Vol 21 No 3
 

Diabetic retinopathy (DR) is a major complication of diabetes and a growing problem as the systemic disease becomes more prevalent. DR develops insidiously from an asymptomatic form through to vascular damage that leads to oedema and breakdown of the blood-retinal barrier (BRB). The Akimba mouse is a cross between the Ins2Akita the Akita diabetes model and the trVEGF029 (Kimba) mouse in which photoreceptors transiently express VEGF. The resultant Akimba has a retinal microenvironment similar to advanced DR in humans. Fluoroscein leakage showing BRB damage was seen in the Kimba and Akimba mice but not Akita or wild-type mice. BRB damage was associated with angiogenesis. Moreover, mRNA for plasmalemma vesicle associated protein (PVLAP) a molecule only found in damaged BRB, was raised in Kimba and Akimba mice. However, pericyte drop-out, and decreased endothelial junction protein expression was seen only in Akimba mice These data suggest that the recently-developed Akimba mice which combines hyperglycaemia and high intraocular VEGF expression may be a good model for human DR.

Reference

Molecular analysis of blood-retinal barrier loss in the Akimba mouse, a model of advanced diabetic retinopathy.
Wisniewska-Kruk J, Klaassen I, Vogels IM, et al.
EXPERIMENTAL EYE RESEARCH
2014;122(5)123-31.

Retina, Vitreous and Uvea

B-scan ultrasonography
Reviewed by: Nana Theodorou
Vol 21 No 3
 

B-scan ultrasonography is commonly employed for the diagnosis and follow-up of ocular trauma. This retrospective study looked at the accuracy and predictive ability of B-scan ultrasonography following open globe repair. Of the 965 patients identified with open globe injuries at the Massachusetts Eye and Ear Infirmary, 210 patients were considered suitable for B-scan ultrasonography. The time of scan ranged from day one to five years with a median of nine days after the repair. Mean patient age was 43 years with 73% of the patients been male. The team analysed 427 scans with the main outcome measure as the final visual acuity. The scan analysis revealed 59 serous choroidal detachments, 57 retinal detachments, 47 haemorrhagic choroidal detachments, 19 retinal tears, 18 vitreous traction and 10 kissing choroidal detachments. The ultrasound had a 100% positive predictive value for diagnosing retinal detachment and intraocular foreign body. The authors conclude B-scans are cost-effective and reliable for assessing open globe injuries.

Reference

B-scan ultrasonography following open globe repair.
Andreoli MT, Yiu G, Hart L, et al.
EYE
2014;28:381-5.

Retina, Vitreous and Uvea

Early surgery for epiretinal membrane
Reviewed by: Nana Theodorou
Vol 21 No 3
 

This was a retrospective case review study in 120 consecutive patients with idiopathic epiretinal membrane. The average patient age was 72 years with a mean follow-up of 6.5 months. Inclusion criteria consisted of symptomatic patients with visual acuity of 1.0 LogMAR or better (VA was measured in Snellens). Preoperatively patients were either pseudophakic or underwent combined phaco–vitrectomy. The mean preoperative VA was 0.44 LogMAR and postoperatively the mean VA was 0.23 showing statistically significant results. Two patients underwent repeat vitrectomy. Evaluation of parameter coefficients indicated that a delay in surgical procedure corresponded to a decrease in VA units. The procedures were classed as early, medium or late. This study serves as evidence that early surgery in these patients is indicated to achieve good VA outcomes with the need of further studies into timing and prognosis.

Reference

Early surgery for epiretinal membrane preserves more vision for patients.
Andreoli MT, Yiu G, Hart L, et al.
EYE
2014;28:410-4.

Retina, Vitreous and Uvea

Effect of laser wavelength on delivering effective burns through opaque lens using pattern scan laser
Reviewed by: Bheemanagouda Patil
Vol 21 No 3
 

Panretinal photocoagulation (PRP) has been used in the treatment of various retinal disorders for many decades. Conventional single-spot lasers take quite some time to do with significantly higher pain, anxiety and photophobia when compared to the pattern scan laser (PSL). It has been shown in previous studies that conventional single spot laser with longer wavelength, such as red (647nm) and yellow (568nm), showed better efficacy in delivering laser burns when compared to green argon (514nm) laser. This study evaluates the effects of pattern scan laser wavelength in delivering appropriate laser burns to mice retina through an opaque lens. Three eyes with clear lenses were used as controls. With the green laser, there were only 3.0±2.0 appropriate laser burns in eyes with opaque lens compared to 13.7±4.0 effective burns in eyes with clear lens. On the other hand, longer wavelength lasers produced 18±5.2 (yellow) and 13±1.5 (red) appropriate laser burns in eyes with opaque lens. The study concluded that pattern scan lasers with longer wavelengths produced more effective laser burns when compared to pattern scan green laser.

Reference

Effect of laser wavelength on delivering appropriate laser burns through the opaque lens using a pattern scan laser.
Hirano T, Lesato Y, Imai A, et al.
OPHTHALMIC RESEARCH
2014;51(4):204-9.

Retina, Vitreous and Uvea

MicroRNA mediate retinoblastoma signal transduction
Reviewed by: Graham Wallace
Vol 21 No 3
 

MicroRNAs (miR) are small non-coding single-stranded RNA molecules, normally 22 nucleotides long. There is a large family of miR that control protein expression by binding to mRNAs, leading to their degradation. One important role of miR is in tumours where they may promote, via down-regulation of suppressor proteins, or prevention by down regulation of oncogenic proteins. In this study miR21, which has been shown to be involved in proliferation, metastasis and anti-apoptosis of tumour cells, was analysed in retinoblastoma. miR21 expression was increased in a human Rb cell line, HXO-RB44, and Rb tissue, compared to normal retinal tissue. Antisense-miR (22 nucleotides), or seed-targeting 8mer oligonucleotides, transfected into cells led to a significant decrease in proliferation, migration and colony-forming in vitro. Antisense miR downregulated miR21 levels while the 8mer oligonucleotide did not. To determine the pathways involved in the inhibition phosphorylation status of HXO-RB44 cells treated with anti-MiR21 was assessed. Levels of phosphorlyated signal proteins such as BAD and Akt were downregulated. The data supports a role for miR21 in retinoblastoma and that inhibition of this miR could have therapeutic value.

Reference

Seed-targeting anti miR-21 inhibiting malignant progression of retinoblastoma and analysis of their phosphorylation signalling pathways.
Ding Y, Wu M, Liu J, et al.
EXPERIMENTAL EYE RESEARCH
2014;122(5):1-8.

Retina, Vitreous and Uvea

Progression of myopic maculopathy after treatment
Reviewed by: Sofia Rokerya
Vol 21 No 3
 

The authors report on a retrospective study carried out to evaluate long-term progression of myopic maculopathy and functional outcome in eyes treated for myopic choroidal neovascularisation (CNV) and in eyes without CNV. Fifty-four myopic eyes of 30 patients were included in the study. Data was obtained by medical records. Eyes were assigned to four groups (PDT, IVR, PDT + IVR, dry myopic maculopathy) and evaluated for best-corrected visual acuity, colour fundus photography and spectral-domain optical coherence tomography. Chorioretinal atrophy progression was quantified manually by a certified grader in all colour fundus photographs and also in the fundus autofluorescence (FAFs) performed during the last visit, using RetmarkerAMD® software (Critical Health SA, Portugal), a semi automated system. No significant differences in morphological and functional outcomes were found, on a long-term basis for three different therapeutic modalities - PDT, IVR and PDT + IVR. The morphological changes in treated eyes are more likely to be related with the natural progression of the myopic maculopathy than with the treatment modality. In eyes treated for CNV the area of macular atrophy increased significantly until the final evaluation. This reconfirms previous reports that chorioretinal atrophy can develop long after CNV has regressed, both in treated and non-treated eyes. More studies with long-term follow-up are needed to determine the real efficacy of different treatments for myopic CNV. Less myopic eyes had a better final BCVA (r=0.437, p=0.012, and r=0.458, p=0.006 respectively). Final BCVA was also inversely correlated with total and central areas of macular atrophy, (p < 0.01). Limitations of the study include the small sample size and the lack of a control group.

Reference

Progression of myopic maculopathy after treatment of choroidal neovascularization.
Farinha CL, Baltar AS, Nunes SG, et al.
OPHTHALMOLOGICA
2014;231:211-20.

Retina, Vitreous and Uvea

Ranibizumab versus laser in diabetic macular oedema (LUCIDATE study)
Reviewed by: Efrosini Papagiannuli
Vol 21 No 3
 

The aim of this study was to compare the functional and structural effects of Ranibizumab versus macular laser treatment in patients with diabetic macular oedema. It was a single centre, prospective, randomised, single masked clinical trial spanning a 48 week period. Thirty-three eyes of 33 patients with centre involving diabetic macular oedema were included, with best corrected visual acuity of 55-79 ETDRS letters at baseline. At baseline they were randomised 2:1 to either three loading doses of Ranibizumab with re-treatment as required every four weeks or macular laser, which was repeated every 12 weeks as required. The outcome measures were divided into a) structural outcomes, such as greatest linear dimension and area of foveal avascular zone, capillary drop out grade, and morphologic characteristics on spectralis OCT and b) functional outcomes, such as visual acuity, retinal sensitivity on microperimetry, electroretinograms and colour contrast sensitivity. They were reported at 12, 24 and 48 weeks. The results showed that the Ranibizumab group had gained 6.0 letters, had improved colour contrast thresholds, better retinal sensitivity and improvements in electrophysiologic function, whereas the laser group had lost 0.9 letters. Ranibizumab was also superior in improving the retinal thickness and structure in diabetic macular oedema, with no signs of progressive ischaemia. The authors therefore concluded that Rabibizumab was indeed superior to laser therapy in the treatment of diabetic macular oedema. They also felt that their comprehensive methodology could be adopted for future studies.

Reference

A randomized trial to assess functional and structural effects of Ranibizumab versus laser in diabetic macular edema (the LUCIDATE Study).
Comyn O, Sivaprasad S, Peto T, et al.
AMERICAN JOURNAL OF OPHTHALMOLOGY
2014;157:960-70.

Retina, Vitreous and Uvea

Resolution of mid-peripheral schisis in x-linked retinoschisis with the use of dorzolamide
Reviewed by: Huw Edward Oliphant
Vol 21 No 3
 

X-linked retinoschisis (XLRS) is an early onset hereditary retinal dystrophy. It is caused by mutations of the RS1 gene. Common manifestations of XLRS are schitic lesions at the macula, as well as infero-temporal schisis. Carbonic anhydrase inhibitors have previously been shown to reduce intraretinal cystoid spaces. This paper describes the resolution of a mid-peripheral schisis with the use of topical dorzolamide. In this case a 34-year-old male presented with long standing difficulties with both near and distance vision, with a best corrected visual acuity of 20/40-2 in either eye. Spectral domain optical coherence tomography (SD-OCT) demonstrated macular schisis as well as a mid-peripheral schisis. A diagnosis of XLRS was made with a finding of a mutation within the RS1 gene. The patient was treated with 2% topical dorzolamide three times a day, for three months. At three month review, a definite reduction in the intraretinal cystic spaces was found with a reduction in the intraretinal spaces in the mid peripheral retina as well. Vision was not significantly altered, being 20/40+2 in either eye at review. This is the first report of this nature, and demonstrates the potential of using carbonic anhydrase inhibitors in XLRS, and that it may be of at least some use. The correlation with visual function is still unsure.

Reference

Resolution of mid-peripheral schisis in x-linked retinoschisis with the use of dorzolamide.
Collison FT, Genead MA, Fishman GA, et al.
OPHTHALMIC GENETICS
2014;35(2):125-7.

Retina, Vitreous and Uvea

The choroid in pregnancy
Reviewed by: Khadijah Basheer
Vol 21 No 3
 

During pregnancy there can be different types of ocular changes including a decrease in corneal sensitivity, increase in central corneal thickness and curvature, decrease in intraocular pressure, central serous chorioretinopathy and ocular blood flow. Advances in ophthalmic imaging devices has allowed for more detailed understanding of the choroid, which is responsible for the majority of ocular blood flow. This study evaluated the subfoveal choroidal thickness measured by enhanced depth imaging optical coherence tomography (EDI-OCT) in pregnant women and compared their results to age matched non-pregnant controls. They found that the mean subfoveal choroidal thickness in their study group was significantly thicker by an average of 40 microns. There was no significant correlation between subfovealchoroidal thickness and spherical refraction, intraocular pressure, axial length, central corneal thickness, ocular perfusion pressure, gestational age, maternal weight gain or foetal weight. The results from this study leave much to be answered, as we cannot tell from these results alone the significance of choroidal thickening in pregnancy. They put forward the idea that the increased choroidal thickness may be secondary to other physiological changes during pregnancy such as decrease in total vascular resistance, plasma protein concentrations and total plasma osmolarity decrease whilst the cardiac output and blood pressure remain unchanged. This study does show that the choroid can be seen in more detail using EDI-OCT and this may be able to give us more information in other cases where choroidal thickness is found to be abnormal such as age-related macular degeneration and myopia.

Reference

Evaluation of subfoveal choroidal thickness in pregnant women using enhanced depth imaging optical coherence tomography.
Kara N, Sayin N, Pirhan D, et al.
CURRENT EYE RESEARCH
2014;39(6):642-7.

Retina, Vitreous and Uvea

Uveitis in HIV infected persons
Reviewed by: Anjali Gupta
Vol 21 No 3
 

Before the advent of highly active antiretroviral therapy (HAART), uveitis, in particular cytomegalovirus (CMV) retinitis, was the most common cause of visual loss in patients with AIDS. HAART has altered the cause of ocular disease in HIV infected individuals by elevating the CD4 cell count. However, uveitis still occurs in this group of patients. The aim of this retrospective case series was to ascertain the spectrum of uveitis conditions in HIV infected individuals presenting with ocular inflammation when the peripheral CD4+ T lymphocyte count was over 200 cells/µL. Sixty-one patients were included in this study from seven tertiary referral inflammatory eye disease clinics in the USA. The median CD4 cell count at presentation of uveitis was 421 cells/µL. Eighty-two percent of the patients were being treated with HAART. The HIV load varied from undetectable to 137 705 copies/ml. The median was undetectable. Uveitis was unilateral in 47.5% and bilateral in 47.5% of patients. Anterior uveitis was the most common type in 47.5% of patients, followed by anterior / intermediate (16.4%), posterior (14.8%), panuveitis (14.8%), with the least common being intermediate uveitis (6.6%). The cause of the uveitis was infectious in 34.4% of patients and immunological in 27.9%. The most common infectious cause was syphilis in 16.4% of patients followed by herpetic anterior uveitis in 6.6% and acute retinal necrosis in 6.6%. Immune recovery uveitis was the most common defined immunological disorder, with all nine cases associated with previous CMV retinitis. There was no significant difference in the CD4 cell count between the infectious and immunological groups. The authors conclude that in HIV infected patients with a presenting CD4 cell count >200 cells/µL, the anatomical location of uveitis is in a similar distribution to the general uveitis population, but infectious causes of uveitis are more common (34.4% vs 15.4%), particularly ocular syphilis (16.4% vs <2%).

Reference

Uveitis in human immunodeficiency virus-infected persons with CD4+ T-lymphocyte count over 200 cells/µL.
Rose-Nussbaumer J, Goldstein DA, Thorne JE, et al.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2014;42:118-25.

Retina, Vitreous and Uvea

Visual fields and OCT in hydroxychloroquine retinopathy
Reviewed by: Brian Ang
Vol 21 No 3
 

It has been recommended that patients on hydroxychloroquine be monitored regularly for retinopathy. However, there has not been an agreement as to the best screening test for hydroxychloroquine toxicity, which may include visual fields (VF), fundus autofluorescence, spectral domain optical coherence tomography (SD-OCT) and multifocal electroretinography. The authors report on a retrospective study of patients with hydroxychloroquine toxicity over a 20-year period. There were 150 patients who had toxicity, defined as clear parafoveal scotomas between two and six degrees on 10-2 VFs or clear parafoveal thinning and damage on SD-OCT. Eleven patients had relatively complete ring scotomas on VFs despite seemingly normal SD-OCT. However, all other patients with clear parafoveal damage on SD-OCT demonstrated some focal areas of parafoveal VF loss. This indicates that up to 10% of patients with hydroxychloroquine toxicity can manifest prominent ring scotomas first before any abnormality is seen on SD-OCT. The results from this study suggest that screening for hydroxychloroquine toxicity should include both 10-2 VF testing and SD-OCT to provide the optimum specificity and sensitivity.

Reference

Disparity between visual fields and optical coherence tomography in hydroxychloroquine retinopathy.
Marmor MF, Melles RB.
OPHTHALMOLOGY
2014;121:1257-62.

Visual Psychophysics

Blinking and driving
Reviewed by: Khadijah Basheer
Vol 21 No 3
 

Spontaneous blinking is dependent on cognitive processes and is regulated by a central pacemaker that is highly sensitive to the attention demands and cognitive workload of the visual task in hand. There is evidence of a variability in the frequency of spontaneous blinking with differing amounts of cognitive workload, for example reading, computer work, during a conversation and in silent primary gaze. In addition, saccade eye movements are accompanied by a suppression of visual input. There is evidence to suggest that saccadic suppression is stronger for small gaze shifts (such as reading) but weaker with increasing saccade amplitude. Saccades have been found to be accompanied by a blink and occur in relation to large ocular movements. This study aimed to explore the joint influence of cognitive demands and large amplitude saccades on spontaneous blink rate. Twenty volunteers were recruited and instructed to follow a 60-minute real life driving circuit while a video camera recorded ocular movements and blinking. Each volunteer was taken through five different complexity levels to increase the amount of cognitive workload. They monitored spontaneous blink rate and horizontal saccades. Saccades were classified according to their amplitude and blink-saccade pairs were also recorded. The results showed consistent responses of spontaneous blink rates and saccades within the same complexity levels, although there was high inter-subject variability. At different complexity levels there was no statistically significant difference in spontaneous blink rate. However, the number of large amplitude gaze shifts increased with complexity levels. An average of 87.5% of large amplitude saccades were accompanied by a blink, so the study concludes that the number of blink-saccade pairs increased with higher complexity levels as well. This study shows that in complex dynamic visual settings, spontaneous blinking accompanied by large amplitude saccades plays a role in counteracting the reduction in blink rate associated with high cognitive demands.

Reference

Blinking and driving: the influence of saccades and cognitive workload.
Cardona G, Quevedo N.
CURRENT EYE RESEARCH
2014;39(3):239-44.

ACTA OPHTHALMOLOGICA

Effects of topical anaesthetic on intraocular pressure
Reviewed by: Nana Theodorou
Vol 21 No 2
 

This prospective interventional study assessed the effects of repeated intraocular pressure (IOP) using Goldmann applanation tonometry and applanation resonance tonometry in six volunteers. Previous literature supports IOP reduction using repeated applanation tonometry. Repeated IOP measures were taken alternately on 12 eyes for one hour using oxybuprocaine / fluorescein in the right eye and tetracaine in the left. The left eye was photographed before and repeatedly for 20 minutes after the IOP measurements. To minimise mechanical influence, the same volunteers received the same amount of anaesthetic drops for one hour but without repeated IOP measurements. A total of 120 or 132 IOP measurements were performed per eye in one hour. Side-effects included punctate corneal erosions in four eyes with tetracaine. The results indicated a significant IOP reduction with both applanation methods greater with oxybuprocaine. The reduction was for the oxybuprocaine-treated eyes, -4.4mmHg and -3.8mmHg, respectively and in tetracaine eyes, -2.1mmHg. Additionally there was a significant drop in anterior chamber volume immediately after the IOP measurements that returned to the original level after two minutes. After one hour of receiving anaesthetic eye drops (without IOP measurements), the IOP decreased significantly in the oxybuprocaine eye for both methods, -3.1 and -1.7mmHg, respectively, but not in the tetracaine eye (P=0.72). The authors postulate that the significant reduction of IOP seen with both topical anaesthetics is possibly due to the anaesthetic effect and the movement of aqueous humor due to mechanical applanation.

Reference

Effects of topical anaesthetics and repeated tonometry on intraocular pressure.
Johannesson G, Hallberg P, Eklund A, et al.
ACTA OPHTHALMOLOGICA
2014;92:111-5.

ACTA OPHTHALMOLOGICA

Gender variations in retinopathy
Reviewed by: Nana Theodorou
Vol 21 No 2
 

The Tromso Eye Study is a substudy of the Tromso Study; a population based longitudinal study based in Norway. The extensive 5869 participants had no diabetes and were aged between 30-87 years. Retinal images from both eyes were taken using the PRONM retinal camera and were graded using the Clinical Diabetic Retinopathy And Diabetic Macular Oedema Scale. Data was also collected on risk factors from self-reported questionnaires, clinical exams and case note review. Retinopathy was present in 15% of the participants and men had a higher prevalence than women (15.9% versus 14%). All severe cases (0.4%) of proliferative retinopathy were due to retinal vessel occlusion. The authors discuss which conditions were associated with each of the genders. In men, retinopathy was associated with hypertension and HbA1c. In women it was associated with age, log-transformed urinary albumin excretion and hypertension. The authors offer an in depth discussion into the associated risk factors and conclude there is a strong association between retinopathy and blood pressure.

Reference

Sex differences in risk factors for retinopathy in non-diabetic men and women: The Tromso Eye Study.
Bertelsen G, Peto T, Lindekleiv H, et al.
ACTA OPHTHALMOLOGICA
2014;92:316-22.

ACTA OPHTHALMOLOGICA

Optical coherence tomography in patients exposed to vigabatrin
Reviewed by: Nana Theodorou
Vol 21 No 2
 

Vigabatrin is used to treat epilepsy and can lead to increased levels of gamma-aminobutyric acid (GABA) in the brain and in the retina leading to binasal visual field defects. Although not the first line of treatment for adults it is still used in epileptic children. Monitoring visual fields accurately is challenging in children hence the need for alternative testing. The study team evaluated the visual fields from adult patients attending routine clinic follow-up for vigabatrin medication. Twelve patients with suspected vigabatrin attributed visual field defects were selected for the study. They were re-examined with computerised kinetic perimetry, ff-electroretinogram (ERG) and optical coherence tomography (OCT) (2D circle scan). All patients demonstrated constricted visual fields. Comparative analysis of ff-ERG parameters showed reduced b-wave amplitudes for the isolated and the combined rod and cone responses (P<0.0001). The a-wave, reflecting photoreceptor activity, was reduced (P=0.001), as well as the summed amplitude of oscillatory potentials (P=0.029), corresponding to inner retinal function. OCT measurements demonstrated attenuation of the retinal nerve fibre layer (RNFL) in nine of 12 patients, most frequently superiorly and / or inferiorly. No temporal attenuation was found. Significant positive correlations were found between the total averaged RNFL thickness, superior and inferior RNFL thickness and reduced ff-ERG parameters. Positive correlations were also found between RNFL thickness and isopter areas. The results are encouraging and OCT measurement of the RNFL thickness may be of clinical value in monitoring patients especially children on vigabatrin therapy.

Reference

Attenuation of the retinal nerve fibre layer and reduced retinal function assessed by optical coherence tomography and full-field electroretinography in patients exposed to vigabatrin medication.
Kjellstrom U, Andreasson S, Ponjavic V.
ACTA OPHTHALMOLOGICA
2014;92:146-57.

ACTA OPHTHALMOLOGICA

Visual defects in deaf children and young adults
Reviewed by: Nana Theodorou
Vol 21 No 2
 

This literature review article serves as a great update on the current evidence relating to visual defects in the young deaf population. There is a good introduction with background information and demographic data relating to UK hearing impairment. The authors have made good use of tables to summarise a hearing loss overview and associated visual defects. The main section is divided into four sections and each section concentrates on a specific visual area such as; refractive and binocular anomalies, visual performance, ocular abnormalities and near vision. The authors incorporate current and past research findings into the allocated sections linking the findings into clinical practice. A good discussion follows with consideration into unexplored areas and the need for further studies especially in relation to near vision.

Reference

Visual performance and ocular abnormalities in deaf children and young adults: a literature review.
Hollingsworth R, Ludlow AK, Wilkins A, et al.
ACTA OPHTHALMOLOGICA
2014;92:305-10.

AMERICAN JOURNAL OF OPHTHALMOLOGY

Epiretinal membranes in uveitic macular oedema
Reviewed by: Efrosini Papagiannuli
Vol 21 No 2
 

Epiretinal membrane (ERM) formation in uveitic macular oedema is a fairly common structural complication of the retina. The authors describe a retrospective case series of 104 eyes of 77 patients with uveitic macular oedema from a tertiary centre. The treatment they received varied from regional (periocular / intravitreal) cortico-steroids, oral corticosteroids, immunosuppression or a combination of regional and oral corticosteroids. The aim of the study was to characterise the effect of the ERMs on visual acuity and on improvement or resolution of the uveitic macular oedema. The ERMs were diagnosed by two investigators with the aid of spectral-domain optical coherence tomography (OCT) and they were scored for the presence or absence of surface wrinkling. This was evident on OCT as multifocal attachments between the ERM and the internal limiting membrane, creating hyporeflective spaces between them and numerous folds along the internal limiting membrane. The outcome measures included best corrected visual acuity, central subfoveal thickness, macular oedema improvement rates (>20% reduction in central subfoveal thickness) and resolution (reduction of central subfoveal thickness <315 m). The authors identified ERMs in 72 eyes of 59 patients. There was no significant difference between eyes without ERM and eyes with ERM but no surface wrinkling. However, eyes with ERMs and surface wrinkling were associated with worse vision (>2/200) at presentation and worse mean visual acuities at three and six months. Snellen acuity at three months in eyes without ERM was 20/35, in eyes with ERM but no wrinkling 20/47 and in eyes with ERM and wrinkling 20/94. Similarly at six months mean visual acuity in eyes without ERM was 20/36, in eyes with ERM but no wrinkling 20/46 and in eyes with ERM and wrinkling 20/110. In terms of structural changes, at six months the eyes without an ERM had a mean central subfoveal thickness of 338 +/-23m, eyes with an ERM but no surface wrinkling had a mean central subfoveal thickness of 332+/-20m, whereas eyes with an ERM and surface wrinkling had mean values of 405+/-22m. The authors concluded that eyes with uveitic macular oedema aggravated by the formation of ERM with wrinkling had a poorer visual acuity outcome, worse response to treatment and thicker maculae at six months. The authors were aware of the limitation of their study because of small sample size, its retrospective nature and possible referral bias and recommended caution in interpreting their results.

Reference

Epiretinal membranes in uveitic macular oedema: effect on vision and response to therapy.
Lehpamer B, Moshier E, Pahk P, et al.
AMERICAN JOURNAL OF OPHTHALMOLOGY
2014;157:1048-55.

BRITISH JOURNAL OF OPHTHALMOLOGY

Ocular Trauma Scores in paediatric open globe injuries
Reviewed by: Jonathan Chan
Vol 21 No 2
 

This is a retrospective case series of 71 open globe injuries in children of less than 18 years of age, with a minimum follow-up period of one year, between 1 September 1992 to 31 July 2011, from the Eye Department of Ophthalmology of the Medical University of Graz, Austria. The aim of the study was to assess the predictive value and applicability of the ocular trauma score (OTS) for paediatric eye injuries. The OTS and paediatric OTS (POTS) parameters analysed for their impacts on visual outcome included initial visual acuity, glove rupture, endophthalmitis, perforation of the globe, retinal detachment, age, wound location (I=cornea, II=anterior 5mm of the sclera, III=posterior to zone II, as defined by the Ocular Trauma Classification Group), iris prolapse, hyphaema, organic injury object, delay of surgery >48 h, traumatic cataract and vitreous haemorrhage. All POTS and OTS parameters were routinely assessed, except for the relevant afferent pupillary defect (RAPD). The authors found that the initial visual acuities, retinal detachment, wound locations (p=0.001 each), lens injuries (p=0.001), posterior segment injuries (p=0.002), traumatic cataracts (p=0.010), hyphaema (p=0.011) and vitreous haemorrhage (p=0.026) had significant impacts on the final visual outcome. The authors reported that the assessment for the absence or presence of mild degree of relative afferent pupillary defect was difficult due to the cooperation of the trial at the time of the assessment. Therefore, calculating the OTS without evaluation of the RAPD was easily applicable for the initial examinations while remaining significantly prognostic with other parameters (p<0.001). The predictions of the POTS correlated with the actual final visual acuities (p<0.001), but several POTS variables (i.e., iris prolapse, age, organic injuries and delay of surgery >48h) had only limited impacts on visual outcome. The authors concluded that the OTS score has a very good predictive value for the visual outcome after open globe injuries in children, even without evaluation of RAPD.

Reference

Ocular Trauma Scores in paediatric open globe injuries.
Schorkhuber MM, Wackernagel W, Riedl R, et al.
BRITISH JOURNAL OF OPHTHALMOLOGY
2014;98:664-8.

BRITISH JOURNAL OF OPHTHALMOLOGY

Secondary iris-claw anterior chamber lens implantation in patients with aphakia without capsular support
Reviewed by: Jonathan Chan
Vol 21 No 2
 

This retrospective, non-randomised, non-comparative, interventional study including 128 eyes of 124 patients that presented with aphakia with no capsular support. All patients consecutively underwent Artisan iris-claw intraocular lense (IOL) implantation between 1997 and 2010. The inclusion criteria were: aphakic without capsular support; significant ametropia (hyperopia) and poor binocular single corrected visual acuity with glasses or contact lenses; contact lens intolerance; presence of vitreous contacting the corneal endothelium; subluxation of a pre-existing intraocular lens in the posterior chamber of the eye; anterior chamber depth >3.0mm; corneal endothelial cell count greater >1800 cells/mm2, intraocular pressure within normal limits (with or without hypertensive drops); absence of retinal disease; and a minimum follow-up of one year. The authors reported that the mean age of the study patients was 54.55 years (range, 1-98 years). The mean follow-up period was 31.8 months (SD 23.63). The mean preoperative logarithm of the minimum angle of resolution best spectacle corrected visual acuity (BSCVA) and spherical equivalent (SE) were 0.67 ((SD) 0.53) and 9.63 D (SD 5.50), respectively. At the end of one year postoperative period, the mean logarithm of the minimum angle of resolution BSCVA improved to 0.52 (SD 0.46) (p<0.05), and remained stable for up to a period of five years. One year postoperative, the mean spherical equivalent was -0.52 (SD 2.21) (p<0.05). The mean preoperative cECC was 2237.47 cells/mm2, decreased over the years (p+0.05). At five years the endothelial cell count was 1961.40 cells/mm2. A slight but statistically significant decrease in cECC was observed (p<0.05). The main complications were: pupillary block; transient raised intraocular pressure; IOL replacement; penetrating keratoplasty; cystoid macular oedema. The authors concluded that the iris-claw IOL implantation in aphakic eyes is an effective, predictable and safe procedure in the first five years of follow-up. However, recommended long-term follow-up in prospective studies is required to demonstrate its long-term safety.

Reference

Secondary iris-claw anterior chamber lens implantation in patients with aphakia without capsular support.
Guell JL, Verdaguer P, Elies D, et al.
BRITISH JOURNAL OF OPHTHALMOLOGY
2014;98:658-63.

CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY

A review of chromosome 9p21 POAG susceptibility locus
Reviewed by: Anjali Gupta
Vol21 No2
 

Primary open angle glaucoma (POAG) is a genetically complex disease and the overall phenotype is influenced by multiple traits including intraocular pressure (IOP), central corneal thickness and structural features of the optic nerve head. Therefore, genes affecting any of these are likely to influence the risk of developing POAG. Many genome wide association studies (GWASs) have been conducted and multiple genetic loci were found to be associated with POAG. However, chromosome 9p21 was the only locus to yield a consistently strong association in subsequent replication studies across different populations including Australians, Americans, Europeans, Japanese and Afro-Caribbeans. A particularly strong association was found between the risk alleles of CDKN2B/CDKN2B-AS (cyclin-dependent kinase inhibitor 2B and 2B antisense) on 9p21 to both high tension POAG and normal tension glaucoma (NTG), but there was a greater level of significance to the NTG group. It was postulated that carriers of the risk alleles are predisposed to glaucomatous optic neuropathy either in a way that is independent of IOP or via an increased vulnerability of the retinal ganglion cells to IOP, even at levels considered normal for most of the population. CDKN2B encodes for p15INK4b, which is an inhibitor of cyclin-dependent kinase 4 that plays an important role in the maintenance of cell cycle progression. This may consequently cause retinal ganglion cell apoptosis, however, the exact molecular mechanism linking the association between CDKN2B/CDKN2B-AS1 and POAG is unknown. The authors conclude that this discovery is still a work in progress and that further research is necessary to understand the pathogenetic molecular pathways linking POAG to 9p21.

Reference

Chromosome 9p21 primary open-angle glaucoma susceptibility locus: a review.
Ng SK, Casson RJ, Burdon KP, et al.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2014;42:25-32.

CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY

Prostaglandin associated periorbitopathy
Reviewed by: Anjali Gupta
Vol 21 No2
 

Prostaglandins are known to cause periorbital adverse effects. The aim of this retrospective case series was to compare the frequency of prostaglandin associated periorbitopathy (PAP) between bimatoprost, latanoprost and travoprost users. Five PAP findings were evaluated: upper lid ptosis, deepening of the upper eyelid sulcus, dermatochalasis involution, loss of the periorbital fat pad and enophthalmos. One hundred and five consecutive patients with glaucoma or ocular hypertension were included in this study and one of the three prostaglandin drops was used in one eye for each patient for more than one month. The contralateral eye of each patient was used as a control. Fifteen patients were included in the bimatoprost group, 70 in the latanoprost group and 20 in the travoprost group. The results showed that PAP was most frequent in the bimatoprost group with at least one PAP feature found in 93.3% of bimatoprost users compared with 70% in the travoprost group and 41.4% in the latanoprost group. The most frequent PAP finding in all groups was loss of the periorbital fat pad followed by dermatochalasis involution. The deeper tissue changes (sulcus deepening, ptosis and enophthalmos) were all more frequent in the bimatoprost group than the travoprost and latanoprost groups. The authors conclude that PAP is common amongst prostaglandin users and is most severe in bimatoprost users.

Reference

Prostaglandin associated periorbitopathy in patients using bimatoprost, latanoprost and travoprost.
Kucukevcilioglu M, Bayer A, Uysal Y, Altinsoy HI.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2014;42;126-31.

CORNEA

Outcomes of corneal collagen crosslinking (CXL) in pseudophakic bullous keratopathy (PBK)
Reviewed by: Sharmina Khan
Vol 21 No 2
 

This was a retrospective non-comparative, interventional case series of 50 eyes in 50 patients with symptomatic PBK who underwent CXL (epithelium-off). Central corneal thickness (CCT), pain score, best corrected visual acuity (BCVA), and corneal transparency were recorded at baseline; at day seven, day 15; and one, three, and six months after the CXL. The mean pain score decreased from 8.1+/-0.6 at presentation to 2.1+/-0.7 on day seven (P=0.0001). Regression was seen in pain scores over six months (5.3+/-1.5). The mean CCT decreased from a preoperatively 724.8+/-78.4 to 694.9+/-77.9um by the end of the first month (P=0.0001) and remained stable at subsequent follow-up. The BCVA improved from log MAR) 2.0+/-0.5 preoperatively to log MAR 1.8+/-0.5 by the end of the first month (P=0.001). The subsequent follow-up showed a progressive deterioration in the BCVA to the preoperative levels at six months. Corneal bullae recurred in 44% (22 eyes) at six months after an initial disappearance. A significant improvement in the BCVA and a lack of recurrence of bullae were significantly associated with a thinner CCT on presentation (<700um). The authors conclude that CXL in symptomatic PBK temporarily improved pain without providing long-term improvement in the BCVA. Case selection is important with more effect seen in patients with a thinner CCT at presentation. Other reports in addition to this support the use of CXL as a useful intervention as a palliative procedure rather than for visual rehabilitation. Those with thicker CCT will have greater irreversible stromal changes and perhaps this is why the authors report a better outcome in those with thinner corneas. It may be an intervention to consider prior to a Gunderson’s flap in a painful blind eye due to bullous keratopathy.

Reference

Outcomes of corneal collagen crosslinking (CXL) in pseudophakic bullous keratopathy (PBK).
Ray NSS, Maharana PK, Sehra SV, et al.
CORNEA
2014;33:243-6.

CORNEA

Topography based keratoconus progression after corneal collagen cross-linking
Reviewed by: Sharmina Khan
Vol 21 No 2
 

Case 1 describes a 35-year-old man with progressive keratoconus (PK). His best corrected visual acuity (BCVA) was right 20/80 (-5.25/-7.75 x 85) and left 20/20 (+4.75/-5.00 x 90). His Ks were right 36.32/48.02 D and 41.15/46.41 D. Right central cornea thickness (CCT) was 327um and left 474um. There was no history of atopy or eye rubbing. In his right eye he had a PK and left eye corneal collagen crosslinking (CXL). Six months later BCVA left eye was 20/20 (+2.50/-3.50 x 100), Ks were 40.48/45.67 D. Three years later BCVA was 20/20 (+2.50/-3.25 x 100). However, there was an increase in Ks (42.74/47.36) i.e. >1.00D. Case 2 was a 29-year-old man with progressive keratoconus. His BCVA was right 20/25 (manifest refraction -1.75/-2.25 x75) and left 20/25 (manifest refraction -3.00/-1.25 x25). Ks were 41.87/43.92D right eye and 40.20/43.28D right eye. Five years later there was an increase in topographic steep K in the left eye, 40.96/45.82 by >1D, the manifest refraction was +0.75/-2.25 x 15. The right eye remained stable. Several studies have reported continued progression of keratoconus in the first year after treatment. These cases report topographic of > 1D progression after >four years post treatment without a reduction in BCVA. The mechanism behind this is not discussed in the report. The area of CXL corneal tissues remodels and regains original thickness > four years on. If the progression of ectasia continues resulting in reduction in BCVA would repeat CXL be an option if there is enough residual stromal tissue? Repeat CXL have been carried out by Seiler and others in women with progressive ectasia following hormonal changes associated with pregnancy. Kanellopoulos has re-treated patients who were first treated with epithelium on. Daya has retreated in post LASIK ectasia.

Reference

Topography based keratoconus progression after corneal collagen cross-linking.
Kymionis GD, Karavitaki AE, Grentzelos MA, et al.
CORNEA
2014;33:419-21.

CURRENT EYE RESEARCH

Complement factor B polymorphism and the phenotype of early age-related macular degeneration
Reviewed by: Huw Edward Oliphant
Vol 21 No 2
 

The relationship between complement factor H (CFH) and age-related macular degeneration (AMD) is very well known, but other genetic polymorphisms relating to AMD are more poorly understood. This study was designed to investigate the relationship between complement factor B (CFB) and early macular degeneration. Three hundred and forty-nine patients were recruited with early macular degeneration in at least one eye from Jules-Gonin University Eye Hospital in Switzerland. Patients were selected on the following criteria; early to intermediate AMD (International Classification and Grading System), no evidence of geographic atrophy or choroidal neovascularisation, over 50 years of age, no diabetic maculopathy, who could have adequate colour photographs of the macula taken, and they were also required to have a blood sample and to consent to the investigation. Severity of AMD was based on drusen size, total drusen, distribution, pigmentary abnormalities and presence of peripheral drusen. Genotyping for polymorphism CFB (R32Q, rs641153) was undertaken for all patients, with the majority being homozygotic for the major allele. This study demonstrated an association of CFB (polymorphism R32Q) with smaller drusen size and with smaller surface coverage by drusen. CFB (R32Q) was also associated with more peripheral drusen. The study is limited by a lack of demographic and environmental data concerning patients, which would clearly be relevant.

Reference

Complement factor B polymorphism and the phenotype of early age-related macular degeneration.
Mantel I, Ambresin A, Moetelli L, et al.
OPHTHALMIC GENETICS
2014;35(1):12-7.

 

CURRENT EYE RESEARCH

Pterygium ocular surface temperature
Reviewed by: Dr Khadijah Basheer
Vol 21 No2
 

This prospective study investigated the ocular surface temperature in patients with pterygia compared to those with dry and healthy eyes respectively. Previous studies have shown that patients with dry eyes show a significant decrease in ocular surface temperature on sustained eye opening compared to controls. The authors of this study argue that accurately evaluating a dry eye in patients with pterygia can be challenging as often Schirmer's tests are normal as there is no impairment of lacrimal secretion, however, tear film break up time can be used as a measure of corneal dryness. This study sought to investigate whether ocular surface temperature could be used as another benchmark to determine whether pterygium surgery is indicated. The results showed a significant decrease in ocular surface temperature in both the pterygium and dry eyes group compared to the control group. Although this study shows that there is a temperature difference similar to dry eye patients it is unclear whether clinics would consider investing in another piece of equipment to determine ocular surface dryness when dry eye is a symptom many patients are vocal about. There are other cheaper and simpler ways of evaluating dry ocular surface, mainly tear film break up time, fluorescein staining and Schirmer’s testing. Furthermore, in these financially strict times, funding for these operations has become an issue and showing a decrease in ocular surface temperature may not be sufficient to overcome this, as opposed to worsening visual acuity or astigmatism.

Reference

Evaluation of ocular surface temperature in patients with pterygium.
Gonnermann J, Maier AKB, Klein JP, et al.
CURRENT EYE RESEARCH
2014;39(4):359-64.

JOURNAL OF GLAUCOMA

Sleep positions and the effect on IOP
Reviewed by: Lorraine North
Vol 21 No 2
 

The authors describe a study to determine if sleeping at a 20 degree head up position decreases nocturnal IOP compared with lying supine in patients with and without glaucoma. They recruited 30 patients (60 eyes) 15 with glaucoma and 15 without. Patients were observed in a sleep laboratory requiring each participant to spend two non-consecutive nights at the lab. Patients slept in the flat position for the first night and with their heads at a 20 degree angle during the second night. Baseline IOP was taken at 10pm immediately after lying down whilst the patient was still awake, throughout the course of the night patients were gently awakened at two hourly intervals and IOP measured with the tonopen. All 30 patients completed the study and no patient had any evidence of angle closure. They found that the 20 degree head up position correlates with lower nocturnal IOP as compared with the supine position in both glaucoma and non glaucoma patients. There was no significant difference between the two groups.

Reference

The effect of positional changes on intraocular pressure during sleep in patients with and without glaucoma.
Lazzaro EC, Mallick A, Singh M, et al.
JOURNAL OF GLAUCOMA
2014;23(5):282-7.

NEURO-OPHTHALMOLOGY

A case report of Horner syndrome with neuromyelitis optica
Reviewed by: Claire Howard
Vol 21 No2
 

This case report details a patient diagnosed with neuromyelitis optica (NMO) with an associated left Horner syndrome. The female patient presented with neck pain and right hemibody decreased pain and temperature sensation. She then went on to develop left ptosis and miosis over the next three days. Magnetic resonance imaging of the cervical spine showed a longitudinally extensive intramedullary lesion more prominent on the left, with post-contrast enhancement extending from C2 to C5. The Horner syndrome was confirmed with 0.5% apraclonidine. In subtle cases of Horner syndrome, cocaine or apraclonidine drops can be used to confirm diagnosis although the latter is used increasingly in the clinical setting. In this case, application of 0.5% apraclonidine drops brought about a reversal of the anisocoria and eliminated the ptosis, confirming the diagnosis. Treatment for NMO has not been proven although opinion for the acute phase recommends intravenous glucocorticoids for five or more days. In this case, such treatment brought about a reduction in symptoms. Long-term immunosuppression for at least five years is recommended in cases of established NMO due to the high risk of relapse.

Reference

Horner syndrome in a case of neuromyelitis optica.
Lovera L, Jay WM, Biller J.
NEURO-OPHTHALMOLOGY
2014;38(2):78-81.

NEURO-OPHTHALMOLOGY

Correlation between structural and functional status of optic nerve and retina in multiple sclerosis
Reviewed by: Claire Howard
Vol 21 No 2
 

Multiple sclerosis (MS) involves autoimmune inflammatory demyelination and axonal degeneration in the central nervous system. Investigation of the retina and optic nerve head (ONH) is an ideal way to visualise this demyelination. This study investigates the functional and structural properties of the optic nerve and retina in patients with mildly disabling MS. A total of 134 eyes were investigated with the eyes of MS patients (some with history of optic neuritis and some without) being compared to a control group. The study also looked at correlation between the structural and functional parameters of the patients’ eyes. Results showed that MS eyes with a previous history of optic neuritis have significant loss of retinal nerve fibre layer thickness compared with healthy controls and unaffected eyes in MS patients. Overall, the structural and functional parameters were worse in MS eyes with a history of optic neuritis compared with non-optic neuritis and control eyes. Also, those with MS eyes (non-optic neuritis) were worse than healthy controls. This study is limited by small numbers as well as inclusion of only mild disability caused by MS.

Reference

Relationship between structural and functional assessment of the visual system in mildly disabled relapsing-remitting multiple sclerosis patients.
Huseyinoglu N, Ekinci M, Ozben S, Buyukuysal C.
NEURO-OPHTHALMOLOGY
2014;38(1):1-7.

NEURO-OPHTHALMOLOGY

Identification and diagnosis of thalamic haemorrhage
Reviewed by: Claire Howard
Vol 21 No 2
 

This paper presents a case of thalamic haemorrhage and discusses clinical findings, providing valuable insight into signs clinicians need to look for. The case presented is of a 76-year-old female who developed left hemiplegia and hemi anaesthesia. Ocular motility testing revealed ‘peering at the tip of the nose’ sign which presented as tonic downward deviation of both eyes and esodeviation of the left eye, with no up gaze beyond midline and abduction deficits bilaterally. Bilateral ptosis was also present. It is important for clinicians to be aware of this sign which is thought to reflect damage to the mesodiencephalic junction, so a rapid diagnosis can be reached. Thalamic stroke may also cause further neuro-ophthalmological defects such as homonymous field defects, visual neglect and pupillary abnormalities, which will vary depending on the location of the lesion.

Reference

Peering at the tip of the nose’ as a sign of thalamic haemorrhage.
Ahmad K, Kumar K.
NEURO-OPHTHALMOLOGY
2014;38(1):21-3.

NEURO-OPHTHALMOLOGY

Use of technology in low vision rehabilitation
Reviewed by: Claire Howard
Vol 21 No 2
 

This article is a review of the accessibility features available on tablets and smartphones for the visually impaired. It explains exactly what the accessibility features are, how to access them and how to use them as well as some useful ‘apps’ for people with low vision. It provides a comprehensive summary and explanation for a number of features that can be used to supplement low vision rehabilitation, along with more traditional devices such as magnifiers and close circuit televisions (CCTVs). Using smartphones and tablets in a patient’s low vision rehabilitation, in addition to traditional devices, can provide versatile options which may be less expensive as well as more socially acceptable. Some of the feature options that can be adjusted to suit a particular visual impairment include contrast, zoom, voice command and audio feedback options. Adjusting and reversing contrast is a simple yet often overlooked feature of smartphones and tablets for the enhancement of reading performance. This clinically useful review also provides a comparison between tablets, smartphones and E-reader devices in terms of price, comfort and size as well as features.

Reference

Tablet and smartphone accessibility features in the low vision rehabilitation.
Irvine D, Zemke A, Pusateri G, et al.
NEURO-OPHTHALMOLOGY
2014;38(2):53-9.

OCULAR IMMUNOLOGY AND INFLAMMATION

Acute retinal necrosis: an Indian experience
Reviewed by: Saruban Pasu
Vol 21 No 2
 

The authors of this retrospective study aimed to provide clinical outcomes in 62 eyes of 53 patients presenting with acute retinal necrosis. All eyes received intravenous acyclovir (10mg/kg tds) for 7-10 days followed by oral antiviral therapy (valaciclovir 1g tds or acyclovir 800mg five times a day). Seventy-two percent of patients were male with a mean age of 36 years. Eighty-three percent had unilateral involvement. In bilateral cases, the average duration to second eye involvement was 210 days. All presented with a main complaint of hazy vision. Two patients were HIV positive. Difference in visual acuity between initial (2.02 logMAR) and final visit (1.78 logMAR) was statistically significant. Fifty-two percent of eyes had 360 degrees of peripheral retinal involvement. Eighteen eyes had retinal detachment at presentation, while 23 eyes developed detachment during the course of the disease. Mean duration between onset of complaints and detachment was 71 days. Aqueous and vitreous samples revealed HSV in 19 and VZV in 28 eyes. No organisms were found in nine eyes. There was no significant difference between detachment rates in lasered versus nonlasered eyes. Thirty-two eyes required surgery (one for vitreous haze, 31 for retinal detachment). Recurrent detachment was seen in 14 of the 31 eyes. Extent of retinal involvement and time interval between onset of disease and start of treatment were significant parameters that affected the visual potential. The authors comment that antiviral therapy minimises progression of unilateral to bilateral disease, and eyes with less than 90% involvement had the best prognosis functionally. Early recognition and aggressive treatment is the cornerstone in managing this serious condition.

Reference

Acute retinal necrosis: clinical features, management and outcomes – a 10 year consecutive case series.
Roy R, Pal B, Mathur G, et al.
OCULAR IMMUNOLOGY AND INFLAMMATION
2014;22(3):170-4.

OPHTHALMIC GENETICS

Differences of the anterior segment parameters in children with Down syndrome
Reviewed by: Huw Edward Oliphant
Vol 21 No2
 

This cross-sectional study was designed in order to demonstrate the differences in anterior segment parameters in children with trisomy 21. This is important as it may impact on surgical planning when undertaking procedures in the anterior segment such as corneal grafting, or cataract surgery. The study looked at 38 children with trisomy 21, and 42 children with no known genetic polyploidy. All patients underwent ophthalmological assessment including; slit-lamp examination, cycloplegic refraction, intraocular pressure measurement (IOP), and Scheimpflug imaging measurement. Scheimflug imaging system (SI) acquires 3-dimensional images by illuminating the anterior segment in different meridians. A weakness of this study is that all of the cycloplegic refractions were undertaken with an autorefractor, and all intraocular pressure measurements were taken with a tonopen. Additionally, children with corneal scar or degeneration were excluded from the study, which is clearly relevant in anterior segment procedures. Comparative groups were in more or less the same age range, being 5-13 in the trisomy 21 group, and 5-12 in the control group. In the group of children with trisomy 21, 44.7% were emmetropic, 31.6% hyperopic, and 23.7% myopic. There was no significant difference in intraocular pressure measurement between the two groups. Central corneal thickness (CCT) was found to be less in the trisomy 21 group, however, and the mean pupil diameter was also significanty less when compared to the control group (but all trisomy 21 patients achieved good dilatation for cycloplegic refraction). The rationale for the finding of thinner corneas in the trisomy 21 is that this may represent the beginnings of ectatic disease. Reassuringly anterior chamber depth, angle and volume were comparable for both children with trisomy 21, and the control group. Overall this study demonstrates largely what is known already, in that significant anterior segment abnormalities lie within the cornea in individuals with trisomy 21.

Reference

Differences of the anterior segment parameters in children with Down syndrome.
Aslan L, Aslankurt M, Aksoy A, et al.
OPHTHALMIC GENETICS
2014;35(2):74-8.

OPHTHALMIC GENETICS

The prevalence of macular cysts in patients with clinical cone-rod dystrophy determined by spectral domain optical coherence tomography
Reviewed by: Huw Edward Oliphant
Vol 21 No 2
 

Cone-rod dystrophy is a progressive photoreceptor disorder which has multiple inheritance patterns. It is rare, with a prevalence of 1 in 40,000. Macular cysts are well recognised in other photoreceptor conditions such as retinitis pigments and choroideraemia, while they are less well recognised in cone-rod dystrophy. In this study 36 patients with cone rod dystrophy were enrolled into the study, with 32 having established disease, and four being new patients. Of the 32 established patients, none had previously been diagnosed with macular oedema, or for that matter had an OCT of the macula. All patients in this study had autosomal recessive subtype of cone rod dystrophy. Of the 36 patients, 17 were shown to have diffuse pigmentary degenerative changes at the macula, and the remaining 19 patients demonstrated normal or negligible ‘mottling’ within the fovea. Of the total 72 eyes that were examined, none demonstrated macular oedema on biomicrosopy or OCT imaging. All, however, did show a degree of retinal thinning. The study is useful in that it demonstrates macular oedema is not a common finding in cone rod dystrophy, but it is limited by the number of participants, and the fact that a number of the participants were related and were therefore likely to have similar genotypes.

Reference

The prevalence of macular cysts in patients with clinical cone-rod dystrophy determined by spectral domain optical coherence tomography.
Salvatore S, Genead MA, Fishman GA, et al.
OPHTHALMIC GENETICS
2014;35(1):47-50.

OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY

Analysis and outcome of explanted hydroxyapatite orbital implants
Reviewed by: James Hsuan
Vol 21 No 2
 

This is a retrospective case series over 11 years of 25 patients with exposed synthetic hydroxyapatite orbital implants who underwent explantation and simultaneous replacement with a dermis fat graft. All patients had signs of infection and had been treated with systemic and topical antibiotics, and had at least 5mm of exposed implant. Eight had had previous surgery in the form of various grafts to treat the exposure. Gram-positive cocci were found in 59%, the remaining 41% were negative. All the implants were sent for histopathological analysis which showed reduced fibrovascular in-growth and chronic inflammation. All patients did well from the dermis fat grafting; none had further orbital surgery and only four needed lid surgery, although one was volume deficient but declined further augmentation. It is unclear from the discussion whether the authors believe that poor initial surgical technique leads to exposure and secondary infection, or poor fibrovascular in-growth into the implant is the primary problem which itself results in exposure and infection. Either way it is clear that once significant exposure and infection have occurred in a porous implant, explantation is preferable to further salvage surgery. The study is useful in showing that simultaneous dermis fat grafting can be undertaken safely with good cosmetic results, and there is no need to postpone this over concerns of infection.

Reference

Management of porous orbital implants requiring explantation: a clinical and histopathological study.
Quaranta-Leoni FM, Moretti C, Sposato S, et al.
OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY
2014;30:132-6.

OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY

Diagnosis and management of orbital vascular malformations
Reviewed by: James Hsuan
Vol 21 No2
 

This is an authoritative review of a controversial and difficult clinical area. The authors have experience of over 350 cases and provide a well-structured review of the classification and management of orbital vascular malformations. They emphasise the need to understand the haemodynamic characteristics of each lesion, which will largely determine not only its clinical behaviour but also the way it is managed. The merits of the different methods available to assess these lesions are described, and the authors stress the importance of dynamic imaging to detect distensible venous lesions, including Valsalva-augmented venous phase CT angiography (a technique described in depth in an accompanying article in the same issue). They then detail the clinical characteristics and imaging findings of the various malformations based on their haemodynamic properties and histology, from high flow arterial lesions to low flow venous and lymphatic malformations, including the mixed and complex variants. Helpful management strategies are provided, with some useful tips gained from their extensive experience, e.g. occasionally some lymphaticovenous malformations may mimic a cavernous haemangioma, but during surgery are found to have an adherent ‘stuck’ tail which would warrant a different, more cautious surgical removal. The limitations of traditional surgical techniques are described, along with newer interventions including intra-lesional sclerotherapy or glueing, either perioperatively with simultaneous excision or via endovascular and percutaneous image-guided approaches.

Reference

Vascular malformations of the orbit: classification and the role of imaging in diagnosis and treatment strategies.
Rootman J, Heran MKS, Graeb DA.
OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY
2014;30:91-104.

OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY

Success rates of primary and revision transcanalicular DCR surgery
Reviewed by: James Hsuan
Vol 21 No 2
 

Transcanalicular laser DCR is a relatively rare procedure compared to more conventional external or endo-nasal techniques. In this article the authors examine the outcomes of revision surgery following failed transcanalicular diode laser dacryocystorhinostomy (TCDL DCR), comparing a conventional external revision with a redo TCDL DCR. They reported a 25% failure rate in 176 primary TCLD DCR procedures. Eighteen of these failures underwent external DCR revision surgery with a success rate of 94.4%, and 16 underwent redo TCLD DCR with a success rate of 43.8% (p=0.002). The main differences between the two techniques are the size of the bony ostium and the creation of a formal mucosal anastamosis with sutured flaps. Previous TCLD DCR did not compromise external revision surgery, and the authors explain this is due to the osteotomy sites being different and therefore the nasal mucosa is not scarred where the flaps are formed. Interestingly the success of redo TCLD DCR is far lower than both revision external DCR and primary TCLD DCR, suggesting the cause of failure during primary TCLD DCR, principally scarring of the rhinostomy, is not adequately addressed during redo TCLD DCR. The 75% success rate of primary TCLD DCR is less than conventional external and endo-nasal non-laser methods, but it may still have a role given it is a quicker and less invasive procedure.

Reference

Comparison of revision surgeries with transcanalicular diode laser and external approaches in cases with failed transcanalicular diode laser dacryocystorhinostomy.
Buttanri IB, Ayintap E, Serin D, et al.
OPHTHALMIC PLASTIC AND RECONSTRUCTIVE SURGERY
2014;30:209-11.

OPHTHALMIC RESEARCH

Allergic conjunctivitis evaluation by thermography
Reviewed by: Bheemanagouda Patil
Vol 21 No 2
 

Thermography is a non-invasive imaging technique, which uses infrared radiation reflected from an object to estimate the temperature of the object. This paper evaluates the use of thermography to assess allergic conjunctivitis objectively, by using an instrument called ocular surface thermographer (OST). Thirteen asymptomatic patients, with proven seasonal allergic conjunctivitis due to cedar pollen, were included in the study. A drop of 0.025% levocabastine ophthalmic suspension was instilled in one eye and artificial tears in the other eye in a masked fashion 10 minutes prior to a conjunctival allergen challenge (CAC). Then a drop of cedar pollen solution was instilled into each eye to induce the allergic reaction. The surface temperature of the inferior conjunctiva and conjunctival injection scores were measured before and 30 minutes after the CAC. After the CAC, the temperature increased by 0.67±0.10˚C in the artificial tear eyes but only 0.21±0.06˚C in the levacobastine eyes. The score for conjunctival injection was 1.38±0.24 and the chemosis score was 0.85±0.25 for the artificial tear eyes and 0.62±0.27 and 0.08±0.08 in the levacobastine eyes (P<0.01). There was a significant correlation between the conjunctival surface temperature and severity of conjunctival allergic reaction. They conclude that OST can be used objectively to evaluate topical anti-allergic agents.

Reference

Evaluation of allergic conjunctivitis by thermography.
Hara Y, Shiraishi A, Yamaguchi M, et al.
OPHTHALMIC RESEARCH
2014;51(3):161-6.

OPHTHALMIC RESEARCH

Effect of single intravitreal injection of bevacizumab on contrast sensitivity in patients with central retinal vein occlusion
Reviewed by: Bheemanagouda Patil
Vol 21 No 2
 

Central retinal vein occlusion is the second most common retinal vascular disorder after diabetic retinopathy. There are many studies reporting the efficacy of intravitreal anti-VEGF injections for macular oedema secondary to retinal vein occlusions. This paper looks at the contrast sensitivity change after single injection of Avastin in patients with macular oedema secondary to central retinal occlusion. Sixteen eyes were included in the study. Contrast sensitivity, best-corrected visual acuity (BCVA), foveal thickness (FT) and macular volume (MV) were recorded before and after treatment with single injection of Avastin. Contrast sensitivity significantly improved at spatial frequencies – 1.5, 3, 6, 12 and 18 cycles per degree (cpd) – one month after the injection and six cpd at three month follow-up. BCVA, FT and MV also improved.

Reference

Effect of a single intravitreal bevacizumab injection on contrast sensitivity and macular thickness in eyes with macular oedema from central retinal vein occlusion: a prospective, nonrandomized, three-month follow-up study.
Preti RC, Ramirez LMV, Pimentel SLG, et al.
OPHTHALMIC RESEARCH
2014;51(3):140-5.

ORBIT

A surgical option for congenital ptosis
Reviewed by: Konal Saha
Vol 21 No 2
 

The authors describe a surgical technique to manage congenital ptosis. They present 30 patients with severe congenital ptosis, MRD1 varying between -2mm and 1mm. Intervention was carried out early to prevent amblyopia. All cases had surgery before age seven with 72% age two or less. The surgical technique involves accessing the frontalis muscle through an upper eyelid skin crease incision then fashioning a flap lateral to the supra orbital neurovascular bundle based laterally. The frontalis flap is then rotated inferiorly and fixed to the tarsal plate. Results were good with all patients having their visual axis cleared at last follow-up (mean follow-up of 27 months) and no sight-threatening complications noted. Three patients required reoperation. The technique offers a useful alternative to more established techniques for managing congenital ptosis which required only one incision, and no foreign material.

Reference

Early frontalis flap surgery as first option to correct congenital ptosis with poor levator function.
Medel R, Vasquez L, Wolley Dod C.
ORBIT
2014;33(3):164-8.

RETINA

Retinal morphology after PASCAL PRP treatment
Reviewed by: Saruban Pasu
Vol 21 No 2
 

The authors of this prospective cohort study set out to report the changes on Spectral Domain-OCT of PASCAL panretinal laser photocoagulation (PRP) treatment for proliferative diabetic retinopathy (PDR) or severe nonproliferative DR (NPDR) and the retinal morphology, from one hour to 21 weeks postoperatively. SD-OCT was performed along the vascular arcades in treated areas, imaging as many of the laser spots as possible. OCT images taken one hour after PASCAL treatment (mean power, 926±434 mW; median, 1,000 mW; n=27 eyes) demonstrated acute morphologic changes including retinal pigment epithelial (RPE) detachment. Laser burns were characterised by bands of increased optical reflectivity that localised to the outer retina, extending from the outer plexiform layer to the photoreceptor layer and RPE. Above each burn, there was upward displacement of the outer plexiform layer toward the inner nuclear layer. The retinal structure in between burns remained unaltered, with no evident damage because of the photocoagulation. RPE detachment was observed in 23 of 27 eyes imaged one hour after treatment. Of the laser spots imaged, 36.1% had RPE detachments and 48.4% of them occurred at the spot edges. Only average laser power and average laser energy were significantly associated with the percentage of pigment epithelium detachments (PEDs) observed one hour after treatment. At laser powers of 550mW or greater, RPE detachment was observed in every eye. The same was true in eyes that received an average laser energy of 12mJ or greater. No RPE detachments were seen in the one to two week follow-up group. On subsequent follow-up the burns had contracted in horizontal and vertical axis and were less reflective. Burn contraction appeared to plateau three to six weeks after treatment. There was downward deflection of the inner retina at each burn, contrasting with the upward deflection seen one hour after treatment. RPE seems morphological similar to its pre-treatment structure by three weeks. A small but significant improvement in visual acuity pre and post treatment was noted. This study provides comprehensive insight into the immediate pathophysiological changes after PASCAL treatment and the evolution of these lesions thereafter.

Reference

Acute retinal pigment epithelium detachments after photocoagulation.
Moysidis SN, Vajzovic L, Gregori G, Goldberg JL.
RETINA
2014;34(4):749-60.

RETINA

Sclerotomy suturing
Reviewed by: Saruban Pasu
Vol 21 No 2
 

This was a retrospective review of 589 consecutive cases of patients who underwent 23-gauge tranconjunctival pars plana vitrectomy. Cases were split into Type 1 vitrectomies (macular hole, ERM and simple vitreous haemorrhages) and Type 2 cases which were more complex requiring more extensive instrument use and torqueing of the globe (e.g. Rhegmatogenous retinal detachment and proliferative diabetic retinopathy with tractional retinal detachment). Clinical and surgical factors were analysed to determine their effects on suturing rates. Overall 227 (38.5%) required at least one sclerotomy suture at the end of surgery. Sixty-nine had one sutured sclerotomy, 52 had two sutured sclerotomies and 106 had three sutured sclerotomies. Surgical technique, tamponade agent and vitrectomy type had significant effects on the incidence of intraoperative suturing. A high suturing rate was observed in cases where no gas tamponade was used and also in Type 2 vitrectomy cases. The overall hypotony rate was 2.2% with a non-statistically significant difference between fluid filled and gas filled eyes. Surgeon experience did not have a significant association with suture rates. Surgical technique was the most significant risk factor for sclerotomy suturing. Differences in particular surgical steps, such as the angle of entry of the trocar, how the cannula is removed, the duration of compression of the sclerotomy site after cannula removal, the IOP at the end of the case, and tolerance for sclerotomy leakage, are all surgeon dependent and certainly affected suturing rates. The authors explain that the Type 2 cases may have had sclerotomies stretched open for longer durations, and more torque on the sclerostomies due to instrument manipulation. They also suggest that more extensive vitreous base dissection reduces the amount of ‘vitreous plugging’, which may aid in sealing the sclerotomy. They comment that careful assessment of the sclerotomy sites at the end of surgery is encouraged in all cases, especially in eyes with these risk factors.

Reference

Rate of sclerotomy suturing in 23-gauge primary vitrectomy.
Duval R, Hui JM, Rezaei KA.
RETINA
2014:34(4);679-83.

STRABISMUS

AC/A correlates
Reviewed by: Fiona Rowe
Vol 21 No 2
 

Three groups of subjects were included in this study. Group 1 had typically developing children from five to nine years with heterophoria less than 6PD. Group 2 had 19 children aged five to nine years with intermittent distance exotropia. Group 3 had 17 naïve young adults and children with near exophoria less than 6PD. Near and distance stimulus accommodative convergence to accommodation (AC/A) assessment with gradient prism cover test after 30 minutes of monocular occlusion was undertaken with a lab method of assessment. Results showed a poor or non-existent correlation between near and distance clinical AC/A ratios. Strong and significant associations were found for lab response convergence accommodation to convergence (CA/A) ratio and near clinical stimulus AC/A ratio. This suggests the near AC/A may reflect accommodative response to change in vergence cues following dissociation of prism cover test and disruption of vergence accommodation.

Reference

The clinical near gradient stimulus AC/A ratio correlates better with the response CA/C ratio than with the response AC/A ratio.
Horwood AM, Riddell PM.
STRABISMUS
2013;21:140-4.

STRABISMUS

AC/A non-linearity
Reviewed by: Fiona Rowe
Vol 21 No 2
 

This study investigated whether or not the response accommodative convergence to accommodation (AC/A) ratio in 30 visually normal subjects is linear with lens presentation order counterbalanced. Accommodative response was measured using the Shin Nippon SRW 500 infrared autorefractor. Accommodation was induced with full aperture trial lenses of strengths of -1.50, -3.00, -4.50 and -6.00DS. Heterophoria was measured with Maddox rod lens. Measurement was also taken at four metres using the modified Thorington technique. Subjects were aged 18-26 years (mean 20.3) and complete data was obtained for 23 subjects. Results showed a lack of linearity across accommodative demands with significant differences found between the -1.50, -4.50 and -6.00DS lenses. The general trend was an increasing responses AC/A with increasing accommodative stimulus. However, large variations occurred across the entire sample for different accommodative demands. No significant difference was found between myopic and non-myopic subjects.

Reference

Non-linearity of the response accommodative convergence to accommodation ratio.
Johnston MS, Firth AY.
STRABISMUS
2013;21:175-82.

STRABISMUS

Angle of deviation and psychological impact
Reviewed by: Fiona Rowe
Vol 21 No 2
 

This questionnaire-based prospective study using the Psychological Impact Questionnaire was designed to investigate whether the size of the angle of deviation, age, sex, presence of diplopia, visual acuity of the worse eye and direction of deviation are related to psychological impact (PI). Fifty patients were recruited: 26 female and 24 male. The average age was 48 years (15-84) and mean PI score was 2.3 (SD 14.3). Average horizontal deviation was 33PD (SD19.8). Two patients had a vertical deviation. There was no correlation with maximum degree of deviation and PI score for horizontal or vertical deviation. There was no correlation for age, sex, diplopia, visual acuity of the worse eye, esotropia or exotropia with PI score. A slight negative correlation was found for visual acuity of the better eye and PI score. However, this may be spurious as a result of the small sample size.

Reference

The psychological impact of strabismus: does the angle really matter?
Ritchie A, Colapinto P, Jain S.
STRABISMUS
2013;21(4):203-8.

STRABISMUS

CFEOM outcomes
Reviewed by: Fiona Rowe
Vol 21 No 2
 

This study presents the orbital and cranial magnetic resonance imaging (MRI) findings of patients diagnosed with congenital fibrosis of the extraocular muscles (CFEOM) along with the surgical procedures and outcomes for ocular motility and strabismus. Nine patients are described: three with type 1, one with type 2 and five with type 3. The condition was bilateral in four and unilateral in five cases. Infraducted primary deviation was reported in eight cases and supraducted in three. Seven cases had abnormal head posture. Eight had severe limitation of horizontal ocular movements and all had limited vertical ocular movements. Exotropia was present in four cases and esotropia in three. All unilateral cases were hypotropic. Six had aberrant movements, binocular vision was absent in eight, amblyopia was present in seven and eight had moderate / severe refractive errors. MRI revealed atrophy of at least one extraocular muscle supplied by the IIIn in all cases. Five had hypoplasia of the IIIn and one had a reduced VIn. Strabismus surgery was undertaken for four cases and two required more than one procedure. Favourable outcome was obtained in two cases. The authors conclude orbital and cranial MRI provides useful information on extraocular muscles and nerves, and surgery should be chosen based on individual findings after treatment of amblyopia and refractive error.

Reference

Congenital fibrosis of the extra ocular muscles: magnetic resonance imaging findings and surgical treatment.
Merino P, Gomez de Liano P, Fukumitsu H, et al.
STRABISMUS
2013;21:183-9.

STRABISMUS

Childhood visual development in albinism and infantile nystagmus
Reviewed by: Fiona Rowe
Vol 21 No 2
 

The authors compare monocular and binocular development measures in 16 children with albinism, 10 with infantile nystagmus (INS) and 72 with normal vision to address interocular acuity differences, crowding ratios and binocular summation rates. The children were aged between four and eight years. There was no age difference between groups. Children with albinism and INS had significantly larger interocular acuity differences than those with normal vision for the single chart and uncrowded chart but no significant differences for crowded charts. Crowding ratios were higher for children with albinism and INS for binocular crowding and the poorer eye. For the better eye, differences were significant for INS only. There was no difference for binocular summation ratios across groups. Strabismus and nystagmus amplitude significantly predicted crowding in the poorer eye for albinism.

Reference

Monocular and binocular development in children with albinism, infantile nystagmus syndrome and normal vision.
Huurneman B, Boonstra FN.
STRABISMUS
2013;21(4):216-24.

STRABISMUS

Near cue responses
Reviewed by: Fiona Rowe
Vol 21 No 2
 

The authors tested subjects with esotropia (13 constant esotropia, 16 fully accommodative esotropia and eight convergence excess) versus age-matched controls and 27 young adult emmetropes for response profiles in comparison to matched control groups. They found responses to the all-cue blur / disparity / proximal (BDP) condition suggested appropriate convergence and accommodation when changing from distance to nearer fixation. Lower response gains were found using impoverished targets and were generally due to poorer responses to near targets and not over-response to distant targets. In non-strabismic subjects they found typical slight accommodation lag for near. Accommodation lag and shallow accommodation were common in strabismic subjects also and particularly in accommodative esotropias with more vergence associated with each unit of accommodation. Children with constant esotropia with weak binocular vision showed very even cue use profiles with no clear pattern of cue use behaviour.

Reference

Accommodation and vergence response gains to different near cues characterize specific esotropes.
Horwood AM, Riddell PM.
STRABISMUS
2013;21:155-64.

STRABISMUS

Orthoptic slit-lamp
Reviewed by:
Vol 21 No 2
 

Adaptations are described that allow the slit-lamp to be used to document squint disorders. Changes are made in the observation system, illumination system, for recording clinical findings and visualisation of clinical findings. The author includes the use of minus lens in front of the slit-lamp objective to obtain a sharp image of both eyes. The narrowed angle between illuminated and observed axis is minimised by holding a 14D prism horizontally in front of the slit-lamp to illuminate the patient’s face and central corneal reflexes. Recording of results is by digital record. Documentation of results is by Microsoft Powerpoint.

Reference

The orthoptic slit lamp.
Gellrich MM.
STRABISMUS
2013;21(4):209-15.

STRABISMUS

Plusoptix referral criteria
Reviewed by: Fiona Rowe
Vol 21 No 2
 

The authors compared various referral criteria on the same group of patients to determine the sensitivity, specificity and predictive value of each. They also programmed the plusoptix to use the 2013 American Association for Pediatric Ophthalmology and Strabismus (AAPOS) referral criteria. They performed a retrospective review of 109 patients. Amblyopic risk factors based on 2003 AAPOS referral criteria were present in 58 cases. Based on the results they recommend that vision screening programmes which use the plusoptix photoscreener should evaluate their own referral criteria and adjust them as needed. Where high sensitivity with good specificity is required, the Matta / Silbert criteria are recommended. For high specificity with reasonable sensitivity, the Arnold criteria are recommended.

Reference

A comparison of referral criteria used by the Plusoptix photoscreener.
Singman E, Matta N, Tian J, Silbert D.
STRABISMUS
2013;21:190-4.

STRABISMUS

Reduced angle after BT for postop diplopia test
Reviewed by: Fiona Rowe
Vol 21 No 2
 

The authors undertook a retrospective study to evaluate the extent of reduced deviation after Botulinum toxin (BT) when used as a postoperative diplopia test. They evaluated effect in 39 patients: 32 exotropia and seven esotropia. The same BT dose was used for all – five units in 0.1ml saline. The median preoperative angle was 40PD (16-78) at near and 40PD (12-77) for distance. The preoperative assessment for follow-up surgery was at a mean of seven months (4-16) after BT injection. Reduced angle of deviation of 15PD or more at either near or distance fixation was noted in 36% of patients. This altered the planned surgery for four cases with a change from 3-muscle to 2-muscle surgery. Reduction was more common for exotropia than esotropia.

Reference

Botulinum toxin as a postoperative diplopia test – it can also reduce the angle of deviation prior to surgery.
Ockrim Z, Weir CR, Yim JL, Cleary M.
STRABISMUS
2013;21(4):199-202.

STRABISMUS

Screening for stroke-related visual problems
Reviewed by: Fiona Rowe
Vol 21 No 2
 

The aim was to report the initial development and evaluation of a suitable screening tool for detecting visual problems after stroke. The tool has four components. The first three include questions asked by examiners about patients’ ocular history and symptoms, observations of ocular appearance and tests of eye movement responses. The fourth component identifies actions, including referral that follow from the first three questions. The authors tested the tool against data collected from 100 examinations of stroke survivors in which there were 498 ocular conditions and visual defects. The tool identified 309 (69%) with a correlation of 0.84. Non-orthoptic professionals identified 85 (17%) with a correlation on 0.34. The authors propose the use of this tool to detect visual conditions in patients with stroke with the potential to support health care practitioners in the better identification of visual function.

Reference

Towards gaining the best information about vision to assist the recovery of a patient with stroke.
Jolly N, Macfarlane A, Heard R.
STRABISMUS
2013;21:145-9.

STRABISMUS

Strabismus detection by Plusoptix S08
Reviewed by: Fiona Rowe
Vol 21 No 2
 

In this study the authors evaluate the accuracy and sensitivity of the Plusoptix S08 photoscreener in detecting strabismus problems in 83 patients aged from six months to 40 years (mean 105 months). A pass was achieved for 25 patients and 58 were referred. These included four with exophoria, 55 with esotropia, 15 with exotropia and nine with horizontal and vertical combined strabismus. The angle measured <20PD in 15 patients, 20-30PD in 24 patients, 30-40PD in 21 patients and >40PD in 21 patients. The overall sensitivity to detection of strabismus was 70%. Sensitivity increased as the deviation angle increased and particularly when >30PD. The authors conclude it cannot be used solely in evaluating strabismus due to the low sensitivity for deviations measuring <30PD.

Reference

Plusoptix S08 sensitivity in detecting strabismus as amblyogenic risk factor.
Moghadam AS, Alizadeh R, Zarei-Ghanavati M.
STRABISMUS
2013;21(4):230-4.

STRABISMUS

Strabismus outcomes after retinal detachment surgery
Reviewed by: Fiona Rowe
Vol 21 No 2
 

A retrospective study reviewed the motor outcomes of strabismus surgery in a cohort of 18 patients who had all previously undergone a scleral buckling procedure to treat retinal detachment. The mean age at strabismus surgery was 48 years (14-67) and median time from scleral buckling surgery to first strabismus surgery was 14.5 months (eight months to 19 years). The preoperative horizontal deviation ranged from 25PD esotropia to 70PD exotropia and vertical deviation ranged from 25PD right hypotropia to 35PD right hypertropia. Eight patients had both horizontal and vertical deviations, seven had horizontal deviations only and three had vertical deviations only. The overall success rate was 33% (six patients). Higher success was noted in the group that had the scleral buckle removed (62.5%) versus the scleral buckle left (10%). There were no retinal re-detachments.

Reference

Strabismus surgery outcomes after scleral buckling procedures for retinal reattachment.
Chang JH, Hutchinson AK, Zhang M, Lambert SR.
STRABISMUS
2013;21(4):235-41.

STRABISMUS

Stroke-vision symptoms
Reviewed by: Fiona Rowe
Vol 21 No2
 

The purpose of this study was to investigate the frequency and type of visual symptoms following stroke and evaluate what certain factors were associated with the absence of visual symptoms. This was a prospective, multi-centre, observation cohort study with 915 recruited patients; 59% male and mean age of 69 years (SD 14). Visual symptoms were reported by 84% (766) either as sole symptoms (56%) or combined as two or more visual symptoms (28%). Visual field loss was reported by 45%, blurred vision by 31%, reading difficulty by 19.5% and diplopia by 19%. Fifty patients had normal ocular examination despite reporting visual symptoms initially but these may have recovered by the time of examination. Sixteen percent (149) were visually asymptomatic: 22 with a normal ocular examination and 32 with aphasia. The authors conclude the presence or absence of visual symptoms does not infer absence or presence of visual impairment and may relate to recovery of visual impairment, visual impairment of mild extent and / or no visual consequence, inattention to the visual impairment or cognitive / communication impairment.

Reference

Symptoms of stroke-related visual impairment.
Rowe FJ, VIS Group UK.
STRABISMUS
2013;21:150-4.

STRABISMUS

Vision screening opinion
Reviewed by: Fiona Rowe
Vol 21 No 2
 

The aim of this paper is to describe experts’ perceptions of best practice guidelines and competency frameworks for visual screening in children. A focus group of approximately 75 minutes duration consisted of five orthoptists and two paediatric ophthalmologists with more than 10 years’ experience in childhood screening. The discussions were recorded and transcribed, followed by qualitative analysis with categorical technique using coded data and classification for conceptual categories. Participants indicated their awareness of the importance of the screening protocol with six tests, importance of false negatives, professional experience and stages in screening. Agreement was reached on six tests to include in screening for children up to three years of age including distance visual acuity, cover test, bi-prism or 4/6 prism, fusion, ocular movements and refraction. The findings provide preliminary support for the use of a core competency framework.

Reference

Expert opinion on best practice guidelines and competency framework for visual screening in children.
Lanca C.
STRABISMUS
2013;21:169-74.

Clinical and Experimental Ophthalmology

Pentacam vs. IOL Master keratometry measurement in IOL power calculations
Reviewed by: Anjali Gupta
Vol 21 No1
 

The IOL Master measures only the anterior corneal curvature and estimates the total corneal power by assuming a fixed relationship between the anterior and posterior corneal surface. The Pentacam measures both the anterior and posterior corneal surface and therefore calculates the true corneal power. The aim of this non-randomised prospective study was to assess whether the Pentacam equivalent keratometry readings (EKR) for three corneal diameter zones (2, 3 and 4.5mm) were significantly different to IOL Master 500 keratometry measurements. Forty-five consecutive patients undergoing routine phacoemulsification and intraocular lens implantation were included in the study. Each patient underwent measurements with the IOL Master and Pentacam prior to surgery. Postoperatively, for each Pentacam EKR and IOL Master measurement, the difference between the observed and expected refractive error was calculated using the Holladay 2 and SRK/T formulae. From this the mean absolute error of refraction (MAE, the distance of the mean refraction from zero) was calculated. The mean keratometric measurements were statistically different between the IOL Master and the Pentacam EKRs in the 2, 3 and 4.5mm zones. However, despite the difference in the keratometry readings, there was no significant difference between the MAE of the IOL Master, EKR 2, 3 or 4.5mm for both the Holladay 2 and SRK/T formulae.

Reference

Comparison of the Pentacam equivalent keratometry reading and IOL master keratometry measurement in intraocular lens power calculations.
Karunaratne N.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2013;41;825-34.

Clinical and Experimental Ophthalmology

Spectral domain OCT vs. confocal scanning laser ophthalmoscope in measuring RNFL thickness
Reviewed by: Anjali Gupta
Vol 21 No1
 

The aim of this prospective study was to compare the retinal nerve fibre layer thickness (RNFL) measurements obtained from the Cirrus optical coherence tomography (spectral domain OCT) with the Heidelberg Retinal Tomograph 3 (HRT3, confocal scanning laser ophthalmoscope). Eighty-eight normal subjects and 85 glaucoma subjects were included and had imaging performed with both the Cirrus OCT and HRT3. VFs with SITA 24-2 were also carried out at the same visit. HRT3 produced thicker measurements both globally and in all four quadrants compared to the Cirrus OCT. However, there was a significant strong correlation between the two imaging modalities for all paired measurements of global and sectoral RNFL. For all paired measurements, except for the nasal quadrant, Cirrus OCT showed higher sensitivities for glaucoma detection than HRT3 at similar specificities. The authors conclude that although the thickness measurements by the two technologies are strongly correlated, they are significantly different. Therefore, the measurements are not interchangeable when used in clinical practice.

Reference

Retinal nerve fibre layer imaging: comparison of Cirrus optical coherence tomography and Heidelberg retinal tomograph 3.
Kratz A, Lim R, Rush R, et al.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2013;41:853-63.

Current Eye Research

Topical doxycycline for corneal neovascularisation
Reviewed by: Khadijah Basheer
Vol 21 No1
 

Six eyes with corneal vascularisation were treated with 1% topical doxycycline, four times a day for three weeks. The patients were reviewed at various intervals over a period of one year. The eyes selected had neovascularisation secondary to a variety of conditions, some mild for example corneal epitheliopathy, atopic disease, rosacea keratitis to more severe conditions such as diabetic rubeotic glaucoma and herpetic keratitis. The authors found that five out of six eyes with active corneal vascularisation treated with topical doxycycline showed attenuation and shortening in blood vessels. Although this is a small case series this paper concludes that topical doxycycline could be used in therapy of corneal vascularisation where corticosteroids or anti vascular endothelial growth factor agents are contraindicated or have been ineffective. Further larger studies would be useful to determine the true effectiveness of topical doxycycline on a larger variety of patients with corneal vascularisation, including corneal graft patients.

Reference

The effect of topical doxycycline on corneal neovascularisation.
Jovanovic V, Nikolic L.
CURRENT EYE RESEARCH
2014;39(2):142-8.

Eye

Avastin vs. Volon A for diabetic macular oedema
Reviewed by: Nana Theodorou
Vol 21 No1
 

This prospective randomised interventional clinical trial compared 30 diabetic patients with macular oedema treated with either intravitreal injections of bevacizumab (Avastin) or triamcinolone (Volon A). One group initially received three injections of 2.5 mg Avastin in monthly intervals whilst the second group received a single injection of 8mg Volon A, followed by two sham interventions. Functional and anatomic results were evaluated monthly using ETDRS vision charts and spectral-domain optical coherence tomography. Retreatment after three months was dependent on functional and anatomic outcome. The results showed baseline best corrected visual acuity (BCVA) was 0.30 logMAR and central retinal subfield thickness was 505µm in the Avastin group and 0.32logMAR and 490µm in the Volon A group. After three months, visual acuity improved to 0.23 logMAR (Avastin) and retinal thickness to 358µm and 0.26 logMAR (Volon A) and 308µm. After 12 months, visual acuity further recovered in the Avastin group (0.18 logMAR) but slightly decreased in the Volon A group (0.36 logMAR). Both treatments were effective in the early stages of the disease but after one year BCVA was better in the Avastin group. The authors discuss risk factors and patient selection should be taken into account when selecting appropriate treatment.

Reference

Intravitreal bevacizumab (avastin) versus triamcinolone (Volon A) for diabetic treatment of diabetic macular edema: one-year results.
Kriechbaum K, Prager S, Mylonas G, et al.
EYE
2014;28:10-6.

Eye

Latanoprost in the treatment of congenital glaucoma
Reviewed by: Nana Theodorou
Vol 21 No1
 

The aim of this study was to investigate the glaucoma control of latanoprost therapy in primary congenital glaucoma (PCG) and assess the factors affecting long-term outcome. Eighty-one eyes of 44 patients with PCG and 42 eyes of 29 patients with previous glaucoma surgery that had been treated with latanoprost as primary treatment were included, with age at treatment varying from 1 to 34 months. Patients were re-examined at a study visit to evaluate intraocular pressure, length of glaucoma control with latanoprost, need of further medication or glaucoma surgery, systemic and topical side-effects. In the first group, a success (glaucoma control by latanoprost therapy) was found in 24 eyes (29.6%), whereas 57 eyes (70.4%) had received surgery (45 eyes (55.6%) in the first year); among the eyes with previous surgery, a success was found in 12 eyes (28.6%), 13 eyes (31%) required an additional therapy and 17 eyes (40.5%) had received further glaucoma surgery. No patient discontinued the treatment because of side-effects. Factors related to the failure of the latanoprost treatment were: the high score of severity of glaucoma (P=0.014) and low age at PCG presentation (P=0.042). The authors concluded that long-term treatment with latanoprost is effective in about 30% of the eyes. Factors related to poor glaucoma control included severe glaucomatous alterations and young age at presentation.

Reference

Long-term efficacy of latanoprost in primary congenital glaucoma.
Uva MG, Avitabile T, Reibaldi M, et al.
EYE
2014;28:53-7.

Journal of Cataract and Refractive Surgery

Liquid adhesive bandage for clear corneal cataract incisions
Reviewed by: Anju Kadyan
Vol 21 No1
 

This paper reports a prospective randomised controlled trial of patients undergoing routine phacoemulsification with a 2.75mm clear corneal incision and followed up for 14 days postoperatively. They evaluated wound edge closure, surgically induced astigmatism and foreign body sensation after use of single 10/0 nylon suture or a liquid adhesive bandage compared to a control group with only stromal hydration. Patients with>0.5D astigmatism had on-axis surgery with the rest having a temporal incision, but the impact of incision site and pre-existing astigmatism was not explored across groups. Suturing was associated with the most surgically induced astigmatism (mean 1.3D) than the adhesive and control groups (mean 0.6D each) with no significant change across groups over 14 days. The adhesive group has the least foreign body sensation on visual analogue scores, followed by control group, with the highest being with suture use. The Siedel test was negative in all patients although wound edge closure assessed by fluorescein staining of wound edge was worst with hydration only. An adhesive to aid wound integrity postoperatively is an important tool in our armamentarium but the need in routine cataract surgery may not be adequately justified both in terms of time and cost. The adhesive would need evaluation in more complex cases where there is risk of wound gaping (corneal pathology / burn) or even in a wider range of intraocular procedures.

Reference

Surgical outcomes after application of a liquid adhesive ocular bandage to clear corneal incisions during cataract surgery.
Keynon KR, Uy HS.
JOURNAL OF CATARACT AND REFRACTIVE SURGERY
2013;39:1668-74.

Journal of Glaucoma

A ciliary body tumour
Reviewed by: Lorraine North
Vol 21 No1
 

The authors describe a case report of a 60-year-old woman found to have advanced angle closure glaucoma in her right eye and appositional closure of half of the left eye and no glaucoma. The patient had previously undergone two trabeculectomies to her right eye which showed advanced glaucomatous damage on visual fields; the left eye had no visual field defect and normal intraocular pressure (IOP). Gonioscopy of the right eye showed peripheral anterior synechiae for over 270 degrees completely covering the trabecular meshwork. Indentation of the left eye showed significant relative pupillary block in all quadrants with the nasal angle completely closed by apposition. The nasal trabecular meshwork was lightly pigmented and the temporal angle was open. Ultrasound biomicroscopy (UBM) was performed and showed a ciliary body tumour preventing angle closure. This case report highlights the need for careful gonioscopy.

Reference

A ciliary body tumour preventing angle closure.
Mehanna C, Desjardins L, Puech M, Cohn H.
JOURNAL OF GLAUCOMA
2014;23(2):125-6.

Journal of Glaucoma

Canaloplasty after failed trabeculectomy
Reviewed by: Lorraine North
Vol 21 No1
 

The authors describe the technique of canaloplasty performed in five patients who had undergone previous trabeculectomy and under maximum tolerated medical therapy or insufficient intraocular pressure (IOP) control. Canaloplasty is described by the authors as “a nonperforating blebless technique derived from viscocanalostomy, in which a 10-0 prolene suture is positioned and tensioned within Schlemm’s canal, thus facilitating aqueous outflow through natural pathways (collectors channels and aqueous veins) and can only be performed if the Schlemms canal is open for the entire 360 degrees.” All five patients that had the procedure performed were followed up every six months; the mean reduction in IOP at two years was 15.9mmHg. The authors concluded that although canaloplasty is not normally considered after a failed trabeculectomy in selected cases in which Schlemms canal is intact canaloplasty could be considered.

Reference

Canaloplasty after failed trabeculectomy: a possible option.
Brusini P, Tosoni C.
JOURNAL OF GLAUCOMA
2014;23(1):33-4.

Journal of Glaucoma

Risk calculation variability over time in OHT
Reviewed by: Lorraine North
Vol 21 No1
 

In this study the authors aimed to assess the variability of the well documented risk model from the Ocular Hypertension Treatment Study (OHTS) that identified higher intraocular pressure (IOP), older age, lower central corneal thickness (CCT), greater vertical cup-to-disc ratio (VCDR), and worse pattern standard deviation (PSD) on visual field analysis as independent risk factors for the onset of primary open-angle glaucoma (POAG). They attempted to assess the variability of the OHTS glaucoma risk prediction model in OHT subjects by applying updated risk factor information obtained during follow-up and measuring the variability in the calculated risk over time not just at baseline. This was a prospective longitudinal study over 60 months of 27 patients (54 eyes). Their results showed that seven individuals converted to POAG during the follow-up. At baseline the mean risk of conversion was 14.0 (12%); over the course of follow-up in this study the mean calculated risk was 13.4 (10.7%). The authors showed that there were substantial fluctuations from visit to visit and that reliance on baseline characteristics assumes that risk of progression is linear. Further work is needed to define the frequency with which updated risk factors should be incorporated into prediction models.

Reference

Risk calculation variability over time in ocular hypertensive subjects.
Christian S, Gustavo DMC, Ilana F, et al.
JOURNAL OF GLAUCOMA
2014;23(1):1-4.

Journal of Pediatric Ophthalmology and Strabismus

Cyclo spray vs. drops
Reviewed by: Fiona Rowe
Vol 21 No1
 

The purpose of this study was to investigate whether cyclo spray is better tolerated than cyclo drops and to assess the adequacy of cycloplegia achieved by spray for objective refraction. Cyclo drops were given to 72 children and cyclo spray to 77 children. The mean age was 4.4 years in the drop group and 4.6 years in the spray group. There was no reduction in distress for children aged over seven years; 16.9% did not have adequate cycloplegia with the spray and this was mainly due to dark irides.

Reference

A prospective comparison between cyclopentolate spray and drops in paediatric out-patients.
Syrimi M, Jones SM, Thompson GM, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2013;50:290-5.

Journal of Pediatric Ophthalmology and Strabismus

DTI/MRI results in amblyopia
Reviewed by: Fiona Rowe
Vol 21 No1
 

Diffusion tensor imaging (DTI) is an MRI technique that can evaluate white matter integrity and neuronal connectivity. Normal brain maturation and myelination are associated with reduced water diffusion and increased diffusion anisotropy. The authors aimed to evaluate the anterior optic pathways with DTI in 10 children with unilateral amblyopia, five children with bilateral amblyopia and 10 control subjects. The mean age was 10.8±2.8 years for unilateral amblyopia, 11.5±1.5 years for bilateral amblyopia and 13.8±2.6 years for controls. In unilateral amblyopia eyes and fellow eyes, fractional anisotropy (FA) values were significantly reduced in prechiasmatic regions. Mean diffusivity (MD) values were greater than controls. In bilateral amblyopia, prechiasmatic FA values were lower but not significantly so. MD values were greater in all anatomic regions but were not significant. The findings may indicate a functional underdevelopment of the anterior visual pathways in patients with unilateral amblyopia affecting both eyes.

Reference

Anterior visual pathways in amblyopia: quantitative assessment with diffusion tensor imaging.
Gümüstas S, Altintas O, Anik Y, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2013;50:369-74

Journal of Pediatric Ophthalmology and Strabismus

Normal values with Orbscan IIz corneal topography
Reviewed by: Fiona Rowe
Vol 21 No1
 

This study aimed to establish a database of normative measurements of corneal typography in children aged 5-15 years with the Orbscan IIz corneal topography system. They assessed 100 eyes of 100 children. The mean SimK astigmatism was 0.69±0.35D. The maximum and minimum K values were 44.26±1.55 and 43.56±1.57D respectively. Anterior best fit sphere (ABFS) was 7.92±0.26mm and posterior best fit spheres (PBFS) was 6.46±0.24mm with a ratio of ABFS/PBFS of 1.23±0.02. The most common anterior and posterior corneal elevation pattern was the incomplete ridge. The thinnest site on the cornea had an average thickness of 540±34.03um, mostly in the inferotemporal quadrant.

Reference

Corneal typography and corneal thickness in children.
Reddy SP, Bansal R, Vaddavalli PK.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2013;50:304-10.

Journal of Pediatric Ophthalmology and Strabismus

Risk factor for surgical failure in consecutive XT
Reviewed by: Fiona Rowe
Vol 21 No1
 

This study was designed to determine the success rate among patients with consecutive exotropia after choosing an appropriate surgical method based on medial rectus function and level of exo deviation. The authors conducted an interventional case series study of 40 consecutive cases of exotropia. The mean deviation preoperatively was 29±13PD reducing to 7±7PD at a minimum three month follow-up. Surgical success at <8PD was achieved in 77.5% of cases: 83.3% with medial rectus resection, 81% with lateral rectus recession and 57.1% in combined surgery. The preoperative amount of exo deviation was the only risk factor of surgical failure in this study.

Reference

Surgical results of consecutive exotropia.
Rajavi Z, Feizi M, Mughadasifar H, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2013;50:274-81.

Journal of Pediatric Ophthalmology and Strabismus

Risk factors for consecutive XT
Reviewed by: Fiona Rowe
Vol 21 No1
 

The authors report a retrospective study to investigate possible risk factors leading to consecutive exotropia development in patients who underwent two muscle strabismus surgery to achieve an initial alignment within 10PD. The exotropia group included 25 female and 22 males. The non-exotropic group included 22 females and 32 males. Consecutive exotropia was present in 13% on the first postoperative day, 17% at first month and 40% by the end of the first six months. Risk factors included limited adduction, asymmetrical surgery, presence of amblyopia and anisometropia, although it was acknowledged that anisometropia may be linked with amblyopia.

Reference

Analysis of risk factors for consecutive exotropia and review of the literature.
Yurdakul NS, Ugurlu S.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2013;50:268-73.

Journal of Pediatric Ophthalmology and Strabismus

Risk factors for failed vision screening
Reviewed by: Fiona Rowe
Vol 21 No1
 

Failure rates on vision screening tests were reported by age and racial / ethnic categories in a large sample of children with most aged 6-11 years. Many children resided in lower socioeconomic status areas. Data was taken from 9743 children. Nine hundred and fifty-one children with glasses were significantly more likely to be older and white. Groups did not differ significantly for estimated income. Of 4253 children, 598 failed one or more vision screening tests. Age was significantly associated with failed tests, as was African-American and Hispanic status. Approximately 14% of African-American and Hispanic children failed at least one test compared to 11% of white children. There was a significant difference in screening failure rates based on age and ethnicity depending on the different tests used: far vision test, plus lens test, random dot E test and near point acuity. The 9-11 year children had the highest rate of fails.

Reference

Ocular problems in low income and minority children.
Frick DJ, Olitsky SE, Campbell A, Glaros AG.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2013;50:363-8.

Journal of Pediatric Ophthalmology and Strabismus

Risk factors for further surgery in consecutive ET
Reviewed by: Fiona Rowe
Vol 21 No1
 

he preoperative and postoperative factors around first surgery for exotropia were investigated for predicting second surgery for consecutive esotropia. Fifty-two patients with consecutive esotropia after exotropia surgery were reviewed: 17 required surgery for the esotropia and 35 did not. There was no significant intergroup difference for age at diagnosis, age at first surgery, preoperative exo deviation, refractive error, rate of lateral incomitance or strabismus deviation at one day, three months and six months postoperative. However, amounts of eso deviation at one month postoperative were higher in those requiring surgery.

Reference

Risk factors predicting the need for additional surgery in consecutive esotropia.
Choi YM, Lee JY, Jung JH, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2013;50:335-9.

Journal of Pediatric Ophthalmology and Strabismus

Strabismus in high myopia
Reviewed by: Fiona Rowe
Vol 21 No1
 

The authors report the occurrence of exotropia-hypotropia complex in 15 cases of high myopia. The mean age at presentation was 23.5 years (10-35 years). Only two patients had high bilateral myopia. The mean axial length of the deviating eye was significantly more than the fellow eye: 29.60±1.51mm versus 24.69 ±1.82mm. The mean preoperative angle was 37±9 exo and 13±6 hypo deviation. The position of the extra ocular muscles was interpreted reliably in 93% of cases by orbital imaging. There was no significant displacement found. Eight cases were managed with strabismus surgery and one was found to have a misplaced muscle insertion. No specific aetiological factors were found for this series.

Reference

Exotropia – hypotropia complex in high myopia.
Monga S, KeKunnaya R, Sachdeva V.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2013;50:340-6.

Neuro-Ophthalmology

An unusual case of sellar chondroma
Reviewed by: Claire Howard
Vol 21 No1
 

A single case of chondrogenic neoplasm arising from the base of the skull is presented and discussed. These benign and slow growing tumours in the sellar region are extremely rare and as such this article provides a useful insight and discussion for consideration. The article describes a 63-year-old man presenting with a long history of sexual dysfunction, bilateral vision loss and left nasal obstruction. Endocrine tests showed that all serum levels of anterior pituitary hormones were decreased. MRI imaging showed a large mass lesion in the saddle area, extending upwards to the dorsal sellae, bilateral cavernous sinus and suprasellar region and downwards into the sphenoid sinus and nasal cavity. The optic nerves and chaism were compressed giving a bilateral superior altitudinal visual field defect and reduced visual acuity in both eyes. This man had symptoms lasting for a six-year duration prior to diagnosis so this article highlights the need to recognise signs early to allow early detection and treatment. The patient was treated with hormone replacement and transfusion of plasma and albumin, as well as a two stage surgical procedure. Possible surgical approaches are discussed in detail in the article. The tumour was removed successfully and postoperatively the patient was stable and his visual acuity and visual field defect improved markedly. His pituitary function returned to normal except for hypothyroidism.

Reference

Giant chondroma of the saddle area: case report and literature review.
Qiu L, Zhu Y, Wang H, et al.
NEURO-OPHTHALMOLOGY
2013;37(6):231-8.

Neuro-Ophthalmology

An unusual case report of bilateral abducens paralysis
Reviewed by: Claire Howard
Vol 21 No1
 

In this case report a nine-year-old girl develops bilateral abducens nerve paralysis, caused by vertebrobasilar dolichoectasia. Vertebrobasilar dolichoectasia is characterised by dilation, tortuosity and marked elongation of the vertebral and basilar arteries. Clinical findings result from the compression and displacement of adjacent structures. In this unusual case the child presented with a longstanding large angle esotropia (with four-year history) with bilateral lateral rectus underaction. Magnetic resonance imaging (MRI) revealed compression of both abducens nerves and the pons. Magnetic resonance angiography (MRA) confirmed the dolichoectatic basilar artery. This is an interesting finding in a rare condition, with a manifestation not found to be previously reported in the literature. Often cases of dolichoectasia are asymptomatic. MRA investigations should be considered in cases of unilateral or bilateral nerve paralysis when there is no known cause.

Reference

Bilateral abducens paralysis secondary to compression of abducens nerve roots be vertebrobasilar dolichoectasia.
Ayhan Tuzcu E, Bayaroullari H, Coskun M, et al.
NEURO-OPHTHALMOLOGY
2013;37(6):254-6.

Neuro-Ophthalmology

Using frequency doubling technology perimetry to identify Alzheimer’s disease early
Reviewed by: Claire Howard
Vol 21 No1
 

Alzheimer’s disease is widely reported to be associated with deficits in visual function. Visual disturbances include impaired stereopsis, contrast sensitivity and motion detection. Deficits specific to the magnocellular pathway (MGC) have been identified in Alzheimer’s disease. This article compares the visual field performances of patients with mild Alzheimer’s disease with normal control subjects. The authors detected visual field impairment attributable to the magnocellular pathway using frequency doubling technology – Matrix (FDT-Matrix). The FDT Matrix perimetry is based on an illusion occurring when a grating of low spatial frequency undergoes counter-phase flicking and measures contrast sensitivity. The process selectively tests the function of the MGC pathway. The authors suggest that testing the response of the MGC pathway using this method may be a sensitive method of detecting a field defect. Patients with Alzheimer’s disease took significantly longer to perform the test than controls. There were statistically significant differences in mean deviation and pattern standard deviation values between the two groups. The results imply that the pathogenesis of cognitive decline may be present in the magnocellular pathway, as well as the cortical area, in Alzheimer’s disease. FDT testing may be a useful test for early identification of Alzheimer’s disease, as well
as for follow-up of these patients, especially when visual field testing is unreliable due to cognitive impairment. Further studies are required to further explore the source of visual field loss in
this patient group, as well as the clinical usefulness of FDT
testing.

Reference

Screening for patients with mild Alzheimer’s disease using frequency doubling technology perimetry.
Aykan U, Orcun Akdemir M, Yildirim O, Varlibas F.
NEURO-OPHTHALMOLOGY
2013;37(6):239-46.

Ophthalmology

Antibiotic prophylaxis after intravitreal injections
Reviewed by: Brian Ang
Vol 21 No1
 

The use of topical antibiotics as prophylaxis after intravitreal injections is a contentious issue, especially now with increasing use of intravitreal anti-VEGF agents. In the Wills Eye Institute, prior to May 2011, all patients undergoing intravitreal injections in the office setting routinely received post-injection topical antibiotics four times daily for four days. However, the practice of post-injection antibiotics was discontinued practice-wide from September 2011 onwards. Apart from the cessation of post-injection antibiotics, there were no other changes to the technique of preparing for and administering the injections (with a 30- or 31-gauge needle). Topical 5% povidone iodine was applied pre-injection, but sterile draping and eyelash preparation were not used. The authors retrospectively compared the incidence of endophthalmitis following intravitreal injections during and after the post-injection topical antibiotic period. During the 28-month post-injection topical antibiotic period studied, 57,654 injections were administered with 28 cases of suspected endophthalmitis (0.049%) and 10 culture-positive endophthalmitis (0.017%). During the nine month period when post-injection topical antibiotics were discontinued, 34,900 injections were administered with 11 cases of suspected endophthalmitis (0.032%) and four culture-positive endophthalmitis (0.011%). The difference in endophthalmitis rates between the two groups was not statistically significant. This is the largest reported series of intravitreal injections so far, and the results are very compelling in demonstrating that post-injection topical antibiotics do not reduce the risk of endophthalmitis and in fact may even increase the risk of endophthalmitis. The evidence is clear that there is no role for routine post-injection antibiotic prophylaxis.

Reference

The role of topical antibiotic prophylaxis to prevent endophthalmitis after intravitreal injection.
Storey P, Dollin M, Pitcher J, et al.
OPHTHALMOLOGY
2014;121:283-9.

Ophthalmology

Cost-effectiveness of femtosecond cataract surgery
Reviewed by: Brian Ang
Vol 21 No1
 

Femtosecond laser-assisted cataract surgery has become increasingly popular due to the reported benefits of increasing precision and reproducibility of capsulorrhexis, less power and manipulation required during phacoemulsification, better corneal wound architecture, and the ability to place precise arcuate keratotomy incisions if required. With these benefits, it is hoped that there will be improved visual acuity and refractive outcomes, as well as reduced incidence of intraoperative and postoperative complications. However, this technology comes at a cost premium. In this paper, the authors calculate the cost-effectiveness of femtosecond laser-assisted cataract surgery compared to normal phacoemulsification cataract surgery. Using a series of estimates and assumptions, including in the calculation of utility values and quality-adjusted life-years (QALY), the authors found that the cost-effectiveness of using femtosecond laser-assisted cataract surgery was $102,691 per QALY. When calculated relative to routine phacoemulsification cataract surgery, the cost per QALY for femtosecond laser-assisted cataract surgery was $92,862, indicating lack of cost-effectiveness. Femtosecond laser-assisted cataract surgery remained non-cost-effective even when modelling a best-case scenario with 100% visual outcomes, no complications, and at reduced cost to patients. The authors calculated that for cost-effectiveness to be achieved, the cost of femtosecond laser-assisted cataract surgery needs to decrease by at least 50% to 70%. Public hospitals are therefore unlikely to adopt this technology due to the high additional cost and marginal benefits over what is already a very safe and effective cataract surgery technique.

Reference

Cost-effectiveness of femtosecond laser-assisted cataract surgery versus phacoemulsification cataract surgery.
Abell RG, Vote BJ.
OPHTHALMOLOGY
2014;121:10-6.

Ophthalmology

Sutureless 27-gauge needle intrascleral intraocular lens implantation
Reviewed by: Brian Ang
Vol 21 No1
 

The authors report on a prospective, non-comparative, interventional case series of patients undergoing sutureless intrascleral fixation of a posterior chamber three piece intraocular lens (IOL) using a 27-gauge needle for docking. Sutureless techniques have the advantage of not having complex suture manoeuvres, suture-induced inflammation, suture degradation and delayed IOL dislocation from broken sutures. Using a 27-gauge needle has two advantages: the sclerostomy wound will be small enough to be self-sealing, and that the haptic can be docked into the needle and externalised with less risk of haptic damage. The authors also describe 50% thickness scleral cuts 1.5mm in length, parallel to the limbus, 1.7mm from the limbus. One end of the scleral cut is the site of the 27-gauge sclerostomy, and the other end is the start of the scleral tunnel within which the haptic is buried – having a distance of 1.5mm between the sclerostomy and the start of the scleral tunnel means that it is easier to grasp the externalised haptic and insert it into the tunnel. In this case series of 34 patients (average age 67.8 years), the best-corrected logMAR vision increased from 0.48 to 0.17 after three months. The commonest postoperative complications were iris capture (three eyes; 8.6%), transient ocular hypertension (two eyes; 5.7%), and cystoid macular oedema (one eye; 2.9%). In 15 cases, there was follow-up of greater than 12 months – in these cases there were no cases of IOL decentration or significant vision changes. Although this study is limited by its relatively small sample size and short follow-up duration, the results suggest that this is a useful and technically simple technique for sutureless intrascleral IOL implantation in eyes without capsular support.

Reference

Sutureless 27-gauge needle-guided intrascleral intraocular lens implantation with lamellar scleral dissection.
Yamane S, Inoue M, Arakawa A, Kadonosono K.
OPHTHALMOLOGY
2014;121:61-6.

Strabismus

Fusion amplitude with Bagolini glasses
Reviewed by: Fiona Rowe
Vol 21 No1
 

The aim of this study was to determine whether there is a difference between the horizontal prism fusion amplitude measured with and without the Bagolini striated glasses (BSG) in 52 young adults. Subjects had a mean age of 21.06 years, 13.5% were male, 30 were exophoric and seven esophoric. Right eye dominance was present in 36 and left eye dominance in 16 subjects. The results showed significantly smaller fusional ranges obtained with BSG during measurements at near fixation. No differences were found with / without BSG at distance. Ocular dominance had no effect. BSG affects results with altered natural viewing conditions.

Reference

Bagolini glasses: do they affect the horizontal prism fusion amplitude?
Schultinga L, Burggraaf F, Polling JR, Gutter M.
STRABISMUS
2013;21:127-30.

Strabismus

Management of high AC/A esotropia
Reviewed by: Fiona Rowe
Vol 21 No1
 

The purpose of this study was to determine the long-term effect of treating high accommodative convergence to accommodation (AC/A) esotropia with single vision lenses (SVL) compared with the effectiveness of using SVL on patients with basic refractive esotropia and a normal AC/A ratio. The authors identified 23 patients with high AC/A esotropia and 14 patients with refractive esotropia. Patients with high AC/A ratio showed high improvement and low deterioration rates, suggesting SVL is an effective form of treatment for high AC/A esotropia. Average hypermetropia was significantly higher in patients with refractive esotropia than AC/A esotropia. No patients were weaned out of glasses during the study. Each group had a significant decrease in size of deviation at near fixation after five years of treatment with SVL. Control of deviation at near fixation improved in both groups over the follow-up period but this was significantly better in the refractive group than the AC/A group. The AC/A group had significantly increased stereopsis but there was better stereopsis in the refractive group at five years follow-up. The authors found that using SVL to treat high AC/A esotropia did not have a negative impact on the
development of stereopsis and propose SVL as an acceptable form of treatment.

Reference

Single-vision lenses: a comparison of management of high AC/A esotropia and refractive esotropia.
Gerling A, Arnoldi K.
STRABISMUS
2013;21:106-9.

Strabismus

Ocular findings in autism
Reviewed by: Fiona Rowe
Vol 21 No1
 

This retrospective study investigated the ocular manifestations of autistic spectrum disorders (ASD) among children in a paediatric ophthalmic practice setting. Fifty-three patients were identified. Assessments were undertaken for 44 with 68% having autistic disorder, 16% with pervasive personality disorder – not otherwise specified – and 16% with Asperger’s syndrome. Male:female ratio was 3:1. Ocular abnormalities were found in 52%. Strabismus was present in 41%, significant refractive error in 27%, anisometropia in 7% and amblyopia in 11%. The percentage of ocular abnormalities was higher than that in the general population

Reference

Ocular manifestations of autism in ophthalmology.
Black K, McCarus C, Collins MLZ, Jensen A.
STRABISMUS
2013;21:98-102.

Strabismus

Ocular neuromyotonia
Reviewed by: Fiona Rowe
Vol 21 No1
 

The authors report a cohort of ten patients (nine female) with ocular neuromyotonia (ONM) for clinical signs and symptoms, treatment methods and outcome. Six had affected vertical muscles including superior oblique, inferior rectus and superior rectus. Four had affected lateral rectus muscles. Episodes were predominantly every 10-40 minutes and lasting from a few seconds to minutes. Episodes were repeated and recurrent throughout the day. Two cases had previous cranial radiation, two had thyroid eye disease and one had superior oblique myokymia that progressed to ONM. Treatment was typically with carbamazepine or Gabapentin.

Reference

Ocular neuromyotonia: differential diagnosis and treatment.
Roper-Hall G, Chung SM, Cruz OA.
STRABISMUS
2013;21:131-6.

Strabismus

Stereopsis changes with cataract
Reviewed by: Fiona Rowe
Vol 21 No1
 

Stereoacuity was compared preoperatively to six weeks postoperative after cataract extraction and intraocular lens (IOL) implant. The authors evaluated the association of postoperative stereoacuity with visual acuity, age and duration of preoperative symptoms. This prospective study recruited 142 patients: 92
male and 50 female. Stereoacuity was measured in 30% preoperatively and 99% postoperatively, which was significant at p=0.0001. Increase in age was associated with reduced stereoacuity. There was no significant correlation of stereoacuity and duration of symptoms. Postoperative stereoacuity was correlated with postoperative visual acuity in the better eye. No correlation was found for stereoacuity and inter-ocular visual acuity difference.

Reference

Effect of bilateral age-related cataract on stereoacuity.
Manoranjan A, Shrestha S, Shrestha S.
STRABISMUS
2013;21:116-22.

Strabismus

Strabismus in bilateral pseudo-aphakes
Reviewed by: Fiona Rowe
Vol 21 No1
 

The authors evaluated ocular deviation and near stereopsis for five years after bilateral cataract surgery in 88 patients. The results showed that patients with preoperative near exophoria angle greater than 12PD progressed more rapidly to intermittent exotropia after surgery with reduced near stereopsis. Ocular changes occurred in the first two postoperative years and thereafter the ocular deviation increased back towards preoperative values. The authors suggest patients with near exophoria greater than 12PD require long-term follow-up.

Reference

Five-year follow-up of ocular deviation in bilaterally pseudo-aphakic patients.
Hoshikawa R, Ito M, Shimizu K, et al.
STRABISMUS
2013;21:110-5.

Journal of Glaucoma

RAPD in glaucoma screening
Reviewed by: Lorraine North
Vol 21 No1
 

A study was conducted to investigate the relative afferent pupillary defect (RAPD) by swinging flashlight as a potentially useful screening test for glaucomatous optic neuropathy. The authors recruited 107 subjects with or without glaucoma from a clinic population. A medical student with no prior ophthalmology experience was trained to test for RAPD using neutral density filters by a neuroophthalmologist. The student performed this masked study on all subjects and those that showed no RAPD then had the swinging light test repeated with 0.3, 0.6 and 0.9 neutral density filters. A result was deemed positive if the neutral density filter in front of the two eyes with subsequent RAPD testing resulted in an asymmetric pupillary response only when the filter was placed in front of one of the two eyes, but not the other. The medical charts were then reviewed to determine the absence or presence of glaucoma. Subgroup analysis was then performed on 67 subjects who had previously undergone cataract surgery. The authors report that RAPD with neutral density filters demonstrated a sensitivity and specificity of 66.7% and 82.9%, respectively, for all subjects and 68.8% and 88.6%, respectively, for those who had not previously undergone cataract surgery when used to screen for glaucomatous disease. A higher negative predictive value was, however, seen in the subgroup that had undergone cataract surgery. The authors recognised a number of limitations with the study, including clinic setting, personnel performing the test and the test was not deemed suitable for mild or advanced disease. However, this test combined with a number of other screening tests could be performed by a non-ophthalmologist making them useful screening tools.

Reference

Glaucoma screening using relative afferent pupillary defect.
Charalel RA, Lin HS, Singh K.
JOURNAL OF GLAUCOMA
2014;23(3):169-73.

Journal of Glaucoma

SLT short-term results
Reviewed by: Lorraine North
Vol 21 No1
 

The aim of the study was to evaluate the risk of adverse effects and short-term results after 360 degrees selective laser trabeculoplasty (SLT) in glaucoma patients. The authors enrolled 64 eyes of 64 patients all who had poorly controlled primary open-angle glaucoma (POAG) by medical treatment. Patients were assessed for inflammation in the anterior chamber, inflammatory signs in the vitreous and retina intraocular pressure (IOP), both before and after SLT at 24hrs, 14 days, six weeks and three months after laser. The retinal thickness was assessed using spectralis OCT. All SLT procedures were performed by the same experienced surgeon and grading of inflammation, IOP measurement and OCT scanning were conducted by another examiner independently. All patients were treated with SLT for the first time and the authors showed a statistically significant reduction in mean IOP at each interval. There was no statistically significant increase in mean retinal thickness and there were no clinically relevant signs of inflammation in the anterior chamber or vitreous. The authors’ results showed that 360 degree SLT treatment produced no clinically relevant inflammation and the authors did not use any pre or postoperative medications which they believe is the first study to investigate this. Limitations of the study include the missing of post treatment IOP spikes within the first 24hrs. The authors conclude that further similar studies need to be conducted in patients with pseudoexfoliation or pigmentary glaucoma following SLT.

Reference

Adverse effects and short-term results after selective laser trabeculoplasty.
Klamann MKJ, Maier A-K B, Gonnermann J, Ruokonen PC.
JOURNAL OF GLAUCOMA
2014;23(2):105-8.

Strabismus

Extraocular muscle BT after ocular pathology
Reviewed by: Fiona Rowe
Vol 21 No1
 

Management is described for 13 patients who received inferior rectus botulinum toxin (BT) injection for vertical strabismus due to orbital pathology. Patients were aged 19-86 years, eight were female and seven were right eye injections. Orbital pathology included six with idiopathic orbital inflammatory syndrome, three with orbital wall fracture, one optic nerve sheath schwannoma post resection, one lymphoma and one spontaneous superior ophthalmic vein haemorrhage. Each patient had diplopia. Benefit from BT was noted in nine (69%). Follow-up was from three months to three years. A functional cure was achieved in five (38%) with a single BT dose. Benefit was independent on the angle of deviation.

Reference

Role of inferior rectus botulinum toxin injection in vertical strabismus results from orbital pathology.
Bunting HJ, Dawson ELM, Lee JP, Adams GGW.
STRABISMUS
2013;21:165-8.

Acta Ophthalmologica

Exudative age-related macular degeneration
Reviewed by: Nana Theodorou
Vol 20 No 6
 

The authors looked at macular lesions in eyes with newly diagnosed exudative age-related macular degeneration. The eyes of 23 patients were included and tested for visual acuity, contrast sensitivity, microperimetry, optical coherence tomography (OCT) and fluorescein and indocyanine green angiography. The findings indicated decreased retinal sensitivity correlated significantly with the presence of choroidal neovascularisation, haemorrhage, subretinal tissue and retinal pigment epithelium elevation. The most important OCT parameter was the thickness of the retinal pigment epithelium elevation.

Reference

Correlation between components of newly diagnosed exudative age-related macular degeneration lesion and focal retinal sensitivity.
Hautamaki AH, Oikkonen J, Onkamo, et al.
ACTA OPHTHALMOLOGICA
2014;92:51-8.

Acta Ophthalmologica

Retinopathy of prematurity
Reviewed by: Nana Theodorou
Vol 20 No 6
 

This review article describes the pathophysiology of retinopathy of prematurity (ROP). The authors start by introducing the condition and its incidence. There is extensive information on the pathophysiology mechanisms involved in the condition to include normal and pathological retinal development. The first and second phases of ROP are described and the role of growth factors is discussed. There is a section for the genetic component of ROP and discussion on recent study findings to understand the factors that contribute to its aetiology and management. The article provides a good overview of the condition to include evidence from recent studies.

Reference

The pathophysiology of retinopathy of prematurity: an update of previous and recent knowledge.
Cavallaro G, Filippi PB, Bagnoli P, et al.
ACTA OPHTHALMOLOGICA
2014;92:2-20.

British Journal of Ophthalmology

DISC lens slow myopia progression in Hong Kong Chinese schoolchildren
Reviewed by: Jonathen Chan
Vol 20 No 6
 

This is a prospective double-blind randomised trial between September 2007 and October 2009. It included 221 children aged 8-13 years, with myopia between -1 and -5 Dioptres ≤1.00D. There were 111 patients in the defocus incorporated soft contact DISC group and 110 in the single vision (SV) contact lens group. The DISC contact lens is a custom-made bifocal soft contact lens of concentric rings design. It comprised a correction zone in the centre and a series of alternating defocusing and correction zones extending towards the periphery having a proportion of 50:50. The correcting zones matched the distant prescription while the defocusing zones were 2.5D relatively negative. Such design allowed to introduce myopic retinal defocus and to maintain clear vision, simultaneously. The single vision lenses were made using the same material with matching parameters without any defocusing zones. The contact lens fitting was performed according to the cycloplegic refraction, corneal curvature and horizontal visible iris diameter. All the patients were measured including the refractive error and axial length at six monthly intervals. The differences between groups were analysed using unpaired t test. One hundred and twenty-eight children completed this study, 65 in the DISC group and 63 in the SV group. It was found that myopia progressed 25% more slowly for children in the DISC group compared to those in the controlled group (0.3 D per year, 95% CI -0.1 to -0.47 v 0.4 D spheres per year; 95% CI -0.93 to -0.65, p=0.031). In addition it was found that the axial length elongation was less in the DISC group compared to the SV group (0.1mm/year comparing 0.18mm/year in the SV group). The effect of the wearing time further increased to 58% when the children had worn the DISC lenses for seven hours per day or more. The marginal benefit from the increased wearing time was smaller when the wearing time reached eight hours. It was found that myopia in children who wore the DISC lenses for five or more hours per day progressed 46% less than those in the SV group. The authors commented that the major limitation was that there was a high dropout rate (approximately 42%); 3/4 dropped out in the first year. The main reason for both groups was lack of motivation in contact wear. The authors conclude that daily wearing of the DISC lenses significantly slowed myopia progression and axial length elongation in Hong Kong schoolchildren. The findings also show that simultaneous clear vision with constant myopic defocus can retard myopia progression.

Reference

Defocus Incorporated Soft Contact (DISC) lens slow myopia progression in Hong Kong Chinese schoolchildren: a 2-year randomised clinical trial.
Lam CSY, Tang WC, et al.
BRITISH JOURNAL OF OPHTHALMOLOGY
2014;98:40-5.

British Journal of Ophthalmology

Intracameral bevacizumab as an adjunct to trabeculectomy
Reviewed by: Jonathen Chan
Vol 20 No 6
 

This is a 12-month, prospective, randomised, double-masked, placebo-controlled trial of patients who were not controlled medically with open angle glaucoma and scheduled for a primary trabeculectomy. Patients were recruited and randomised during the period between April 2009 and November 2010. In the study group patients received 50µL of either bevacizumab (1.25mg) or placebo balanced salt solution (BSS) peroperatively. The success was defined as intraocular pressure (IOP) ≤18mmHg and >5mmHg with at least 30% reduction from baseline and no loss of light perception. There were 138 patients who completed a 12-month follow-up cycle and of those 69 were in the bevacizumab treated group. The intraocular pressures were measured at one year postoperatively and found to be significantly lower than baseline (placebo: 25.6±9.9mmHg vs. 11.5 ≤3.9mmHg, p<0.01; bevacizumab: 24.8±8.1mmHg vs. 11.9±3.8mmHg, p<0.01) with no difference between treatment groups (p=0.69). It was found that the absolute success was higher in the bevacizumab group (71% vs. 51%) with the need for lowering of the intraocular pressure interventions (needlings) being lower in this group (12% vs 33%). The surgical technique used was by injecting either the study medication (50µL bevacizumab at a concentration of 25mg/mL) or placebo (BSS) solution intracamerally through the paracenteses using a single-use 30-gauge needle. At the end of the procedure, a subconjunctival injection of betamethasone was administered. Topical preparations containing tobramycin and dexamethasone were used as an ointment and then continued four times a day for eight weeks duration. The authors commented that the limitation of this study concerns the inclusion of patients scheduled for trabeculectomy with or without mitomycin C (MMC) use. The authors commented that the standard at the centre for patients without risk of scarring involved the use of MMC only if a low target pressure was deemed necessary. A post-hoc analysis revealed that despite no significant differences in the primary outcome at the 12-month period, bevacizumab could still significantly improve the survival curve in both subgroups (with or without MMC use). The authors concluded that intracameral bevacizumab significantly reduces the need for additional interventions during the follow-up of patients undergoing primary trabeculectomy procedure.

Reference

Intracameral bevacizumab as an adjunct to trabeculectomy: a 1-year prospective, randomised study.
Vandewalle E, Pinto LA, Van Bergen T, et al.
BRITISH JOURNAL OF OPHTHALMOLOGY
2014;98:73-8.

Clinical and Experimental Ophthalmology

Direct endoscopic probing for congenital lacrimal duct obstruction
Reviewed by: Dr Anjali Gupta
Vol 20 No 6
 

The most common treatment for congenital lacrimal duct obstruction (CLDO) is probing, which is traditionally a blind procedure. Previous literature reports success rates between 78-92%. The authors of this retrospective non comparative case series reviewed the success rates of probing with dacryoendoscopy, which enables simultaneous probing with visualisation of the site of obstruction. Ten patients (13 lacrimal ducts) over the age of one year (mean age 40.7 months, range 14-74 months) diagnosed with CLDO who underwent direct endoscopic probing with dacryoendoscopy under general anaesthesia were included in this study. The dacryoendoscope was inserted into the lacrimal drainage system via the punctum. Once the site of obstruction was seen, the endoscope was advanced to perforate the obstructed area. Telephone interviews were performed six months after the surgery to assess the subjective outcome of the procedure. Disappearance of epiphora was reported in 12/13 (92.3%) cases. However, 5/13 (38.5%) reported occasional discharge from the eye. Two of the 13 cases had undergone previous unsuccessful blind probing, one of these two cases had subsequent successful direct endoscopic probing, the other had persistent epiphora. Various sites of obstruction were noted; the most common were the nasolacrimal duct (7/13), Valve of Hasner (2/13), lacrimal sac (2/13) and the canaliculus (2/13). Two of the 13 cases had more than one site of obstruction. No obstruction was seen in one patient but a hypertrophic mucous membrane was noticed and probing had resulted in disappearance of epiphora. There were no complications from intraoperative endoscopy or general anaesthesia. The authors conclude that probing with dacryoendoscopy is a safe and effective treatment method for CLDO but are aware that their conclusions are limited by the small number of cases studied.

Reference

Direct endoscopic probing for congenital lacrimal duct obstruction.
Sasaki H, Takano T, Murakami A.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY

Clinical and Experimental Ophthalmology

PERG as a visual prognosticator in chiasmatic tumours
Reviewed by: Dr Anjali Gupta
Vol 20 No 6
 

Pattern electroretinogram (PERG) allows assessment of ganglion cell function and may therefore be used to assess anterior visual pathway dysfunction. This prospective non-randomised study assessed PERG before and after surgical removal of tumours in and around the sellar region compressing the anterior visual pathways in order to assess its utility as a prognostic tool. Best corrected visual acuity (BCVA), Humphrey visual field (VF) (30-2) and PERG were recorded one week preoperatively, one week and six weeks postoperatively. During PERG, the first negative wave (N1), the first prominent positive wave (P1/P50) and the second large negative wave (N2/N95) were recorded to calculate the N2/P1 ratio. ≥1.1 was taken to be normal and <1.1 was abnormal. Twenty patients (40 eyes) were included. Thirty-one eyes (77.5%) had a normal N2/P1 ratio preoperatively. This increased to 34 eyes (85%) in the early postoperative period and 35 eyes (87.5%) in the late postoperative period. There was no association between PERG and BCVA in the pre and postoperative periods (P=0.369). Of eyes with normal N2/P1 ratio, 47.1% showed an improvement in BCVA, compared to 50% eyes with abnormal N2/P1 ratio. There was also no significant association between PERG and VF pre and postoperatively (P=0.093). Of eyes with a normal N2/P1 ratio, 35.4% showed an improvement in VF postoperatively compared to 22.2% eyes with abnormal N2/P1 ratio. Of eyes with a normal N2/P1, 45.2% showed no change in VF postoperatively compared to 66% with an abnormal ratio. In conclusion, PERG is unlikely to be a useful prognosticator in the preoperative assessment of chiasmatic tumours, as an abnormal N2/P1 ratio is not associated with lesser or no clinical improvement post surgery when compared with a normal N2/P1 ratio.

Reference

Evaluation of pattern ERG as a visual prognosticator in chiasmatic tumours.
Goyal JL, Thangkhiew L, Yadava U, et al.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2013;41:864-9.

Current Eye Research

A relationship between central serous retinopathy and obstructive sleep apnoea
Reviewed by: Dr Khadijah Basheer
Vol 20 No 6
 

This prospective study aimed to evaluate a relationship between central serous retinopathy (CSR) and obstructive sleep apnoea (OSA). Twenty-three subjects (six female and 17 male) were diagnosed with CSR and overnight polysonography was performed to record desaturation and apnoeic episodes. They found that 60% of patients had some form of OSA (mild, moderate, severe). Both CSR and OSA were seen more frequently in the male subjects and there is known to be a male predominance for both these conditions. The mechanism for this relationship is unknown but the authors suggest that it could result from oxidative stress. OSA is a sleep related disorder where repetitive obstruction of airflow in the upper airway leads to chronic recurrent hypoxia and oxidative stress. They hypothesise two mechanisms that connect the two conditions, the first being that oxidative stress causes choroidal vasoconstriction. Previous studies have shown choroidal circulatory disturbance with indocyanine green angiography in patients with CSR. The second mechanism is increased blood coagulation abnormalities as other studies have shown that levels of plasma activator inhibitor 1 (PAI-1) were increased in patients with both CSR and OSA. OSA is also associated with other ocular conditions such as normal tension glaucoma and also increases the risk of cardiovascular and neuropsychological diseases. If this relationship can be confirmed with further prospective studies, patients presenting with CSR should be screened for OSA and a thorough systemic history should be undertaken.

Reference

Obstructive sleep apnoea in patients with central serous chorioretinopathy.
Yavas GF, Kusbeci T, Kasikci M, et al.
CURRENT EYE RESEARCH
2014;39(1):88-92.

Current Eye Research

Macular slippage following macular hole surgery
Reviewed by: Dr Khadijah Basheer
Vol 20 No 6
 

The treatment of macular holes now involves peeling the internal limiting membrane (ILM) as well as vitrectomy and gas tamponade. It has been noted in previous studies that following an ILM peel the morphology of the macula is different. Tadayoni et al. noted numerous arcuate retinal striae along optic nerve fibres and called it ‘dissociated optic nerve fibre layer’ (DONFL). Optical coherence tomography (OCT) has shown that shallow dimples in the optic nerve fibre layer caused the appearance of DONFL. In addition, the temporal retina was found to be significantly thinner, whilst the nasal side was thicker than that in the fellow eye. This asymmetrical parafoveal retinal thickness was thought also to be caused by ILM peeling. This retrospective case study included 27 eyes that underwent macular hole surgery with vitrectomy and ILM peel and analysed the foveal to disc diameter before and after surgery. In addition, OCT images of the macula were also compared before surgery, early postoperatively and 12 months postoperatively. In all eyes included in the study all the post-operative foveal to disc diameters were shorter than preoperative measures. In particular this distance reduced most significantly in those eyes that showed characteristics of DONFL (78%). They conclude that the macula can slip towards the optic disc after ILM peel for macular hole surgery and that DONFL appearances can be seen between 6 to 18 months postoperatively. However, this was a small retrospective case study and it is unclear what clinical impact this may have, as there was no investigation into whether the patients were symptomatic from these changes. Although the anatomical changes are important to note for future fundus examinations in these patients, more research in a larger number of patients should be conducted to determine whether DONFL changes cause any new visual disturbances.

Reference

Macular slippage after macular hole surgery with internal limiting membrane peeling.
Nakagomi T, Goto T, Tateno Y, et al.
CURRENT EYE RESEARCH
2013;38(12):1255-60.

Experimental Eye Research

Autophagy in lens mitochondria loss
Reviewed by: Graham Wallace
Vol 20 No 6
 

The lens consists of a monolayer of epithelial cells that overlies fibre cells that differentiate from epithelial cells at the equator. While developing, fibre cells need mitochondria to provide energy, as they mature they lose these and other organelles to increase transparency and passage of light. Lens epithelial cells maintain mitochondria and supply nutrients and maintain lens homeostasis. Proteosomal and DNA degradation have been shown to have a role to play in organelle loss in fibre cells, but these are not the only mechanisms. Autophagy is a process whether cellular proteins and organelles can be enclosed in phagolysosomes leading to destruction. Degradation of mitochondria specifically is termed mitophagy. Whether autophagy is involved in organelle degradation in the lens is unclear with reports both supporting and refuting this mechanism. In this study, Costello et al. used electron microscopy and dual-label confocal microscopy to demonstrate the presence of autophagic vesicles containing mitochondria in lens epithelial and fibre cells. In support of this serum starvation, a common protocol to induced autophagy, led to mitophagy in primary lens epithelial cells. To date, loss of crystalline activity in clearance of aggregated proteins has been linked to cataract development. Now the autophagy pathway should be included in future studies.

Reference

Autophagy and mitophagy participate in lens organelle degradation.
Costello MJ, Brennan LA, Basu S, et al.
EXPERIMENTAL EYE RESEARCH
2013;116:141-50.

Experimental Eye Research

New mouse model of diabetes mellitus
Reviewed by: Graham Wallace
Vol 20 No 6
 

Diabetic retinopathy (DR) is a serious complication of diabetes. It is driven by the loss of pericytes, cells which control vascular function, due to excess formation of sugar alcohols by the enzyme aldose reductase (AR). AR has been shown to be present in pericytes in retinal capillaries in human and animal studies. Several animal models for DR have been described including dogs, rats and mice. However, the pathways and concentrations of AR activity and production of sugars appears to differ between species. While AR inhibitors were effective in dogs they had only minor benefits in humans. Moreover, accumulation of retinal sugars in streptozotocin-induced diabetic rats was significantly higher than in diabetic mice. Therefore, new model systems in mice with lower AR activity are required. In this paper transgenic mice were produced expressing human AR and green fluorescent protein under the control of the α-smooth muscle actin promoter (SMAA-GFP-hAR). Diabetes was induced by crossing these mice to the naturally diabetic C57BL/6-Ins2Akita/J mice (AK-SMAA-GFP-AR). The results showed that sorbitola levels measured by HPLC were higher in diabetic mice compared to controls. AK-SMAA-GFP-AR mice showed induction of VEGF, IGF-1, bFGF and TGFβ, all vascular angiogenic factors, as well as complementary signalling molecules. A significant increase in acellular capillaries was also seen compared to control mice. The development of this model has several advantages over current animal studies. Manipulating mouse genomes is significantly more advanced than in rats and more antibodies available for analysis. Moreover mice are substantially cheaper to breed and maintain than rats and dogs. The potential for this mouse model to be used in testing new AR inhibitors or other drugs is an obvious benefit of this study.

Reference

Novel transgenic mouse models develop retinal changes associated with early diabetic retinopathy similar to those observed in rats with diabetes mellitus.
Gou C, Zhang Z, Zhang P, et al.
EXPERIMENTAL EYE RESEARCH
2014;119:77-89.

Eye

Long-term outcomes following surgery for traumatic cyclodialysis clefts
Reviewed by: Nana Theodorou
Vol 20 No 6
 

This retrospective case series evaluated the long-term visual prognosis and intraocular pressure control following surgical treatment of traumatic cyclodialysis clefts. Cyclodialysis clefts result from the disinsertion of the longitudinal ciliary muscle fibres from the scleral spur and occur as a result of blunt ocular trauma or anterior segment surgery. Clinical data from 17 eyes was included for patients who underwent indirect and / or direct surgical cycloplexy. All eyes had ocular hypotony with optic disc swelling, macular folds or macular oedema. The main outcome measures included intraocular pressure (IOP), best-corrected visual acuity and the occurrence of postoperative complications. Mean age of the patients was 42 years with 16 men and one woman. Preoperatively, the mean IOP was 6.9mmHg (range, 2-14 mmHg) and postoperatively IOP was up to 70mmHg in 13 eyes. The final mean postoperative IOP was 12.2mmHg with no cases of secondary glaucoma or other serious complications. Preoperatively, best corrected visual acuity was 6/12 or better in 24% eyes, which rose to 71% at the final follow-up. The authors conclude that cyclodialysis clefts can be successfully corrected with direct surgical cycloplexy and / or cleft cryotherapy.

Reference

Long-term outcomes following the surgical repair of traumatic cyclodialysis clefts.
Agrawal P, Shah P.
EYE
2013; 27:1347-52.

Eye

Pain score assessment in babies undergoing treatment for ROP
Reviewed by: Nana Theodorou
Vol 20 No 6
 

The aim of this study was to assess neonatal pain scores during laser treatment for retinopathy of prematurity (ROP) under sub-tenon anaesthetic with oral or rectal sedation. Sixty-two babies were included who have had ROP laser treatment over a seven year period. Pain scores were assessed using the Neonatal Pain Agitation and Sedation Scale (N-PASS) every 10 minutes during laser treatment. The outcome and requirement for re-treatment in this group was compared with that in the intravenous sedation group. Pain scores were available in 19 of the 27 babies treated under sub-tenon anaesthesia. The mean pain score during treatment was 2.7 (SD±1.7, range 0.5–6.2). There was no statistically significant correlation between the mean pain score and duration of treatment, number of laser burns, or post-menstrual age of the baby at the time of treatment. Both treatments were equally successful irrespective of the sedation method. The mean pain scores during laser treatment under sub-tenon anaesthesia were lower than those previously reported during ROP screening or heel-stick procedure. This study supports that sub-tenon anaesthesia with oral or rectal sedation provides sufficient pain control for laser treatment for ROP without the need or risks of intravenous sedation and intubation.

Reference

Pain score assessment in babies undergoing laser treatment for retinopathy of prematurity under sub-tenon anaesthesia.
Novitskaya ES, Kostakis V, Broster SC, et al.
EYE
2013;7:1405-10.

Investigative Ophthalmology & Visual Science

Improved vision with perceptual learning
Reviewed by: Carmel Noonan
Vol 20 No 6
 

This study examined whether the development of crowded near visual acuity can be stimulated and whether crowding effects can be reduced by perceptual learning. The authors compared a magnifier crowded task with a perceptual learning crowded task and perceptual learning uncrowded task in 45 children with visual impairment and 29 children with normal vision. Children with visual impairment showed higher baseline crowding ratios than children with normal vision. Results showed improvement of single near visual acuity for all training groups. The crowded perceptual learning group showed the largest improvement in near visual acuity after training.

Reference

Perceptual learning in children with visual impairment improves near visual acuity.
Huurneman B, Boonstra FN, Cox RFA, et al.
INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE
2013;54:6208-16.

Investigative Ophthalmology & Visual Science

Vision measurements vs. self-rating
Reviewed by: Carmel Noonan
Vol 20 No 6
 

The aim of this study was to evaluate the association between self-rated vision status and tests of visual acuity, contrast sensitivity, stereoacuity, bilateral visual field and self-reported visual function in specific domains of near and far vision. The goal was to determine which variables are most important when subjects rate the quality of their vision. The study sample was 2467 people. They found that multiple components are related to the simple measure of self-rated vision status. Better visual acuity, contrast sensitivity and bilateral visual fields and stereoacuity are associated significantly with better vision status. Better distance visual acuity and contrast sensitivity were most important in increasing odds of better vision status. Analysis of ADVS subscales revealed that better function on near and far vision subscales were significantly associated with better reports of vision status but particularly near vision.

Reference

Associations between self-rated vision score, vision tests and self-reported visual function in the Salisbury Eye Evaluation Study.
El-Gasim M, Munoz B, West SK, Scott AW.
INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE
2013;54:6439-45.

Journal of Glaucoma

Arterial stiffness and PEX
Reviewed by: Lorraine North
Vol 20 No 6
 

The authors describe a study of 25 newly diagnosed patients with pseudoexfoliation glaucoma (PEX) and 25 controls to evaluate carotid femoral pulse wave velocity (CF-PWV) values. The CF-PWV was assessed using a noninvasive device by measuring the pulse transmit time and the distance between two recording sites conducted by a single experienced cardiologist. The study showed that patients with PEX had higher CF-PWV than did healthy individuals despite any difference between other factors such as body mass index (BMI), blood pressure (BP) and total cholesterol that are also predictors of cardiovascular diseases. The authors found an association between PEX and increased arterial stiffness which they felt may be attributed to the accumulation of pseudoexfoliative fibrils in the arterial wall. They report that this could aid diagnosis when in doubt about PEX and could be considered a risk factor for the development of PEX glaucoma.

Reference

Systemic arterial stiffness in patients with pseudoexfoliation glaucoma.
Türkyılmaz K, Oner V, Yüksel C, et al.
JOURNAL OF GLAUCOMA
2014;23(2):108-11.

Journal of Glaucoma

High myopes with POAG and IOP fluctuations
Reviewed by: Lorraine North
Vol 20 No 6
 

The authors describe a prospective study of 80 eyes of Chinese patients with primary open-angle glaucoma (POAG) on prostaglandin analogues to investigate if those who also have high myopia exhibit greater short-term intraocular pressure (IOP) fluctuations at resting conditions over 24 hours and after dynamic exercise. The authors used two protocols for IOP measurement by the same technician. Protocol 1 required all patients to be hospitalised and asked to maintain a supine position for 15 months before the start of the test; measurements were then taken at 8am, 10am, 2pm, 6pm, 10pm, 2am and 6am using pneumatonometer in the sitting position. Protocol 2 examined the IOP after dynamic exercise on the patients after a three day break from protocol 1. IOP was measured using Goldmann applanation tonometry. Their results showed that there was no difference between 24 hour fluctuations at resting conditions for both groups. However, they found a significant IOP fluctuation in patients with POAG and high myopia and the exercise test but the IOP decreased in this group particularly after rapid running compared to other POAG patients. The authors acknowledged the limitation in this study as IOP was measured in protocol 1 using a noncontact pneumatonometer which is not as accurate as Goldman tonometry.

Reference

Intraocular pressure fluctuations in patients with primary open-angle glaucoma combined with high myopia.
Yang Y, Li Z, Wang N, et al.
JOURNAL OF GLAUCOMA
2014;23(1):19-22.

Journal of Glaucoma

Macular thickness and visual fields
Reviewed by: Lorraine North
Vol 20 No 6
 

The authors describe a comparison of spectral domain OCT with Humphrey visual fields (HVF) mean deviation (MD) and pattern standard deviation (PSD), examining the retinal thickness of the macula and circumpapillary retinal nerve fibre layer (RNFL) defects. Seventy-three subjects who met the study criteria were analysed retrospectively. Patients were either diagnosed with glaucoma or glaucoma suspects. Both eyes were included and were analysed separately. The total average macular thickness plus the average macular thickness in superior and inferior macular halves as well as differences in total and macular half-thickness between the right and left eyes were examined. The average thicknesses of the circumpapillary RNFL in the superotemporal and inferotemporal quadrants for each eye were also recorded. MD and PSD HVF parameters were included and asymmetry between the eyes. The cup-to-disc (CD) ratio was also recorded. Correlations were determined using linear regression analysis. The authors found that eyes with a total macular thickness of <270 microns were significantly more likely to be associated with visual field loss by both MD and PSD. Whereas eyes with a total thickness of >300 microns were less likely to be associated with visual field losses. Also, when comparing the two eyes to each other or the superior macular to the inferior macular the visual field loss was associated to the thinner retina or retinal half. The authors demonstrated a strong correlation between RNFL and macular thickness measurements in glaucoma and showed how measurement of both the RNFL and macular thickness could provide useful additional information in the diagnosis and management of glaucoma patients.

Reference

Correlation of macular thickness with visual fields in glaucoma patients and suspects.
Mathers K, Rosdahl J, Asrani S.
JOURNAL OF GLAUCOMA
2014;23(2):98-104.

Journal of Pediatric Ophthalmology and Strabismus

Amblyopia OCT results
Reviewed by: Fiona Rowe
Vol 20 No 6
 

The authors compared the macular and peripapillary retinal nerve fibre layer (RNFL) thicknesses of amblyopic and fellow eyes using Stratus optical coherence tomography (OCT) to reveal any differences. They sought to determine the anatomical differences between these subtypes of strabismic and anisometropic amblyopia. They recruited 25 strabismic (22 esotropia and three exotropia) and 25 anisometropic (21 anisohyperopic and four anisomyopic) subjects. In the anisometropic group macular thickness of amblyopic eyes was significantly greater than the fellow eye. No significant difference in RNFL thickness was found for this group. In the strabismic group, no significant difference between eyes was found either for macular or RNFL thickness.

Reference

Macular and retinal nerve fibre layer thickness in unilateral anisometropic or strabismic amblyopia.
Andalib D, Javadzadeh A, Nabai R, Amizadeh Y.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2013;50:218-21.

Journal of Pediatric Ophthalmology and Strabismus

Intermittent exotropia
Reviewed by: Fiona Rowe
Vol 20 No 6
 

Four cases of intermittent exotropia are discussed. Case 1 was a nine-month-old with cycloplegic refraction of +1.0DS and a 30PD intermittent exotropia at near and distance. Discussions considered observation, part-time occlusion, refractive correction and later possibility of surgery. Case 2 was a three-year-old with intermittent exotropia of 20PD at near but constant at distance and with +1.25 retinoscopy. Discussions considered duration of exotropia, possible surgery, quick follow-up, observation and checks for presence of photophobia. The third case was a five-year-old with 20PD exotropia at near and distance. One eye closed at distance with a retinoscopy of +4.50DS. Discussions considered providing full or partial hyperopic glasses for better visual acuity which may improve control, possible surgery and risk of consecutive esotropia. The final case was a four-year-old with 20PD exotropia at near and 25PD at distance with -1.50DS refraction. Discussions considered giving full minus glasses and observation.

Reference

Eye to Eye: Evaluation and treatment of intermittent exotropia.
Panelists: Alley C, Deutsch JA, Gunton KB.
Moderator: Nelson LB.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2013;50:198-201.

Journal of Pediatric Ophthalmology and Strabismus

Risk factors for amblyopia
Reviewed by: Fiona Rowe
Vol 20 No 6
 

The author presents a meta-analysis of published data to estimate American Association for Pediatric Ophthalmology and Strabismus (AAPOS) prevalence data for amblyopia risk factors. He extracted data from major paediatric comprehensive eye examination studies for children aged two to five years. Prevalence at AAPOS consensus thresholds for risk factors were: anisometropia (1.2%±2%), hyperopia (6%±1%), astigmatism with the rule and 15 degree against the rule (9%±1%), oblique astigmatism (6%±1%), myopia (0.5%±0.1%) and refraction total (23%±2%). Strabismus prevalence was 2%±0.3%. Prevalence of acuity failure of 20/40 or two inter eye line difference was 6%±1%. Total AAPOS risk factors were 31%±2%. Taking interactive risk factors into account reduces refractive and strabismic components to 16%±2%. Assuming 50% interaction with visual acuity and other combined risk factors yields a prevalence of 21%±2%.

Reference

Amblyopia risk factor prevalence.
Arnold RW.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2013;50:213-7.

Journal of Pediatric Ophthalmology and Strabismus

Surgical prediction in infantile ET
Reviewed by: Fiona Rowe
Vol 20 No 6
 

The purpose was to evaluate the preoperative factors influencing the efficacy of the surgical procedure of bilateral lateral rectus recessions. Fifty cases with at least one year follow-up were included for retrospective analysis. Mean response to surgery was 2.17±0.80 PD/mm recession at one week postoperative, 1.79±0.63 at six weeks postoperative and 1.58±0.75 at one year postoperative. Exo drift was 5.12±7.27PD at six weeks postoperative and 8.02±6.81 at one year. A larger preoperative distance deviation was associated with larger surgical response at six weeks postoperative. Younger age at surgery, shorter interval between onset and surgery and larger preoperative distance deviation were associated with larger surgical response at one year. Exo drift and extent of preoperative distance angle should
be considered when determining surgical dose for infantile exotropia.

Reference

Preoperative factors predict the surgical response of bilateral lateral rectus recession surgery in patients with infantile exotropia.
Yam JCS, Chong GSL, Wu PKW, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2013;50:245-50.

Journal of Refractive Surgery

High-fluence collagen cross-linking
Reviewed by: Amit Patel
Vol 20 No 6
 

The authors treat seven eyes with progressive keratoconus with a high energy (18mW) for five minutes delivering a total energy similar to that suggested by the original Dresden protocol (3mW for 30mins). All eyes had a thickness >400µm following epithelial removal and were treated with iso-osmotic riboflavin. Corrected distance visual acuity (CDVA), keratometry (Kmax and K mean) and endothelial cell density (ECD) were measured at each follow-up. No intra or postoperative complications were noted. At one and six months postoperatively, there was no significant change in Kmax, Kmean or ECD. The authors claim that the Bunson-Roscoe law of reciprocity can be applied effectively by increasing the power and shortening the duration of treatment, but acknowledge the small numbers and short duration of study.

Reference

Impact of fluorescein on the antimicrobial efficacy of photoactivated riboflavin in corneal collagen cross-linking.
Richoz O, Gatzioufas Z, Francois P, et al.
JOURNAL OF REFRACTIVE SURGERY
2013;29(12):842-5.

Journal of Refractive Surgery

Prostaglandin levels in femto cataract surgery
Reviewed by: Amit Patel
Vol 20 No 6
 

Following previous reports of pupil size decrease after femtosecond treatment, the authors compare levels of prostaglandins in patients undergoing femtosecond assisted cataract surgery with those having routine cataract surgery. Patients with inflammatory eye disease, previous trauma surgery, age-related macular degeneration (AMD), retinopathy, glaucoma, non-steroidal anti-inflammatory (NSAID) use and small pupils were excluded. Aqueous humour was collected from patients after femtosecond laser pretreatment (n=113) and at the beginning of routine cataract surgery (n=107). In all femtosecond assisted cases, a set capsulotomy size was used and the programmed pulse energy, incision depth and grid spacing were standardised. The total prostaglandin (PG) and the prostaglandin E2 (PGE2) concentrations were measured in two independent studies each using an enzyme-linked immunoassay. In both sets of studies, there was a significantly higher concentration of PG (p=0.0001, p=0.00004) and PGE2 (p=0.0002, p=0.004) in the femtosecond group compared to routine cataract surgery group. No correlation of PG/PGE2 levels with age, cataract density, corneal incision type, suction time or laser time was noted. The authors therefore postulate that the possible trigger for prostaglandin release is from the microplasma of gas and water that results from the laser application. They suggest that patients undergoing femtosecond assisted cataract surgery should be pretreated with topical NSAIDs to avoid intraoperative mioses and postoperative inflammation.

Reference

Changes in prostaglandin levels in patients undergoing femtosecond laser-assisted cataract surgery.
Schultz T, Joachim SC, Kuehn M, et al.
JOURNAL OF REFRACTIVE SURGERY
2013;29(11):742-7.

Journal of Refractive Surgery

Two bifocals and a trifocal
Reviewed by: Amit Patel
Vol 20 No 6
 

The authors compare the optical outcomes of two bifocal intraocular lenses (AcrySof ReSTOR +2.50 Diopter [D] add +3.0D add) with a trifocal lens (AT LISA tri 839MP). The optical qualities of the lenses were quantified by measuring the modulation transfer function (MTF) at five different focal points (0D, -1.5D, -2.0D, -2.5D and -3.0D) and four apertures (2.0mm, 3.0mm, 3.75mm and 4.5mm). At far distance (0D), the bifocal +2.0D lens performed best, at -2.5D and -3.0D, the bifocal +3.0D add lens performed best and the trifocal provided best MTF values at -1.5D. All three lenses had a similar performance at -2.0D. As expected the trifocal lens showed less aperture (pupil) dependence than the bifocal lenses. As an experimental study, the authors acknowledge that the results are obtained for an ideal lens centration and in vivo outcomes may differ due to tilt and decentration.

Reference

Optical quality differences between three multifocal intraocular lenses: bifocal low add, bifocal moderate add, and trifocal.
Madrid-Costa D, Ruiz-Alcocer J, Ferrer-Blasco T, et al.
JOURNAL OF REFRACTIVE SURGERY
2013;29(11):749-54.

Neuro-Ophthalmology

A case report of cavernous sinus syndrome following dental procedure
Reviewed by: Claire Howard
Vol 20 No 6
 

This case report describes a patient presenting with painful diplopia as a consequence of root canal dental treatment. Following root canal treatment a non-resolving tooth pain led to a decision to extract the tooth, leading to onset of severe periorbital pain, diplopia, headache, nausea and vomiting the next day. Magnetic resonance imaging demonstrated a mass lesion in the cavernous sinus. Corticosteroid therapy was started and marked pain relief occurred within 72 hours. Following five months of treatment there was complete resolution of diplopia and a normal appearance of the affected cavernous sinus. Cavernous sinus thrombosis is usually caused by infection but this was not the case here, as the problematic tooth was not infected. The authors question that the cause of ophthalmoplegia could be the intraorbital local anaesthetic injection used. Neuroimaging is suggested in cases of non-resolving cavernous sinus syndromes.

Reference

Painful ophthalmoplegia following dental procedure.
Bahceci Simsek I, Yabas Kiziloglu O, Ziylan S.
NEURO-OPHTHALMOLOGY
2013;37(4):165-8.

Neuro-Ophthalmology

An interesting presentation of ruptured anterior communicating artery aneurysm with acute monocular vision loss
Reviewed by: Claire Howard
Vol 20 No 6
 

The authors report an interesting case of a 60-year-old man presenting with acute monocular vision loss accompanied by periorbital pain as an unusual presentation of subarachnoid haemorrhage (SAH) from ruptured anterior communicating artery aneurysm. The patient did not present with any neurological deficit, which is generally the presenting feature for this condition. In addition, changes in mental status are known to occur which, again, was not found for this reported case. A relative afferent pupillary defect was present in the affected eye. As the anterior communicating artery is located close to the optic nerve, aneurysm should be considered when there is presentation of unilateral decrease in visual acuity with periorbital pain, even in the absence of other neurological signs. Other symptoms to look for include transient headache and / or bitemporal or homonymous hemianopia (due to compression of the optic chiasm or tract). In this case, direct optic nerve compression from perineural haematoma was suggested as a cause for retrobulbar optic neuropathy.

Reference

Acute retrobulbar optic neuropathy as the sole manifestation of subarachnoid haemorrhage from a ruptured anterior communicating artery aneurysm.
Lee K, Young Shin S, Hae Park S.
NEURO-OPHTHALMOLOGY
2013;37(4):172-4.

Neuro-Ophthalmology

Case reports of neuro-ophthalmological complications of CIPD
Reviewed by: Claire Howard
Vol 20 No 6
 

The authors present three cases of neuro-ophthalmological complications of chronic inflammatory demyelinating polyradiculoneuropathy (CIPD). CIPD can lead to prominent nerve hypertrophy which can mimic other forms of neuropathy radiologically. In addition, complications can occur which can cause diagnostic difficulties. All three cases reported have the presence of hypertrophic nerve enlargement. A review of literature for large case series and single case reports shows a small percentage of patients with the disease to have neuro-ophthalmological complications. The neuro-ophthalmological presentation usually occurs following a long history of CIPD. The authors discuss the implication of clinicians being aware of the possibility of CIPD in neuro-ophthalmological presentations, especially if neuro imaging reveals cranial / spinal nerve root hypertrophy or if raised cerebrospinal fluid (CSF) protein is detected. Best treatment for the complications is to treat the underlying condition with appropriate immunosuppression. Other treatment options for refractory papilloedema include acetazolamide, optic nerve sheath fenestration and CSF diversion surgery.

Reference

Neuro-ophthalmological complications of chronic inflammatory demyelinating polyradiculoneuropathy.
Hickman SJ, Allen JA, Baisre A, et al.
NEURO-OPHTHALMOLOGY
2013;37(4):146-56.

Ocular Immunology and Inflammation

Inflammatory macular holes
Reviewed by: Saruban Pasu
Vol 20 No 6
 

The authors present a case of closure of a full thickness macular hole in a patient with Behçet’s disease, without surgery. The 23-year-old male they describe presented with a history of recurrent oral aphthous ulcers and a genital ulcer. Ocular examination revealed inflammation of the anterior chamber and vitreous of the right eye, and periphlebitis and cystoid macular oedema in the left eye. He was prescribed hourly topical corticosteroids, cycloplegics and oral azathioprine. Follow-up examinations revealed the development of a retinal infiltrate in the right eye which promoted the addition of oral cyclosporine A and oral corticosteroids. Three months after initial presentation he developed an attack of panuveitis in the left eye, which was adequately controlled by increasing the dose of oral corticosteroids. Subsequent follow-up revealed a full thickness macular hole in the left eye. The patient was put on the waiting list for surgical closure of the macular hole. In the meantime he developed another attack of panuveitis in his left eye. Subcutaneous interferon alpha-2b treatment was started and tapered accordingly. Two months after treatment the macular hole had fully closed with an increase in the patient’s visual acuity. The authors highlight the role of cystoid macular oedema and abnormal vitreoretinal tractions secondary to inflammation in contributing to macular hole formation. In this particular case the authors suggest that the second attack of inflammation may have caused glial or retinal pigment epithelium (RPE) cell proliferation to bring the hole edges closer together. Subsequent control of the inflammation caused resolution of the cystoid macular oedema and release of vitreous traction. They conclude by saying surgery may be avoided by strict control of inflammation in Behçet’s disease macular holes.

Reference

An exceptional case of full-thickness macular hole closure in a patient with Behçet disease.
Uçar D, Atalay E, Ozyazgan Y, et al.
OCULAR IMMUNOLOGY AND INFLAMMATION
2014;22(1):79-81.

Ocular Immunology and Inflammation

IVTA use in Behçet’s disease
Reviewed by: Saruban Pasu
 

This study aimed to evaluate the efficacy and safety of intravitreal triamcinolone acetonide (IVTA) injection (4mg/0.1ml) in controlling posterior segment inflammation in patients with Behçet’s disease. Medical records of consecutive patients diagnosed with Behçet’s who underwent IVTA between July 2005 and February 2001 were reviewed. Forty-nine eyes of 49 patients were included in the study. A total of 67.3% were on oral prednisolone of more than 10mg/day and 79.6% were on immunosuppressants. At 24 months after injection 49.0% were on a reduced dose or had stopped oral prednisolone and / or second line immunosuppressants. Mean number of acute attacks during one year before injection was 1.93+/-0.85, which reduced to 0.88+/-0.89 during one year after injection (p<0.001). Mean follow-up period after injection was 54.9+/-17.5 months. Mean best corrected visual acuity (BCVA) improved at 1, 3, 6, 12, 18, 24 and final visit (p<0.001). The cumulative survival of inflammation control without relapse was 40.0% at 12 months, 22.5% at 24 months, and 16.4% at 36 months after IVTA injection. During the 24 months after injection, 30.6% needed further injections at a median period of 10 months after the first. After injecting, 25% showed complete resolution of vascular and disc leakage on fundus flourescein angiography (FFA); 68.8% showed incomplete resolution. The cumulative probabilities of cataract surgery for phakic eyes were 13.8% at 12 months, 48.9% at 24 months and 60.2% at 36 months after IVTA injection. Twenty (40.8%) eyes had an elevated intraocular pressure (IOP) post injection. The rate of IOP elevation did not differ according to the history of glaucoma or IOP elevation history (p=0.740). Of these 20, 15 had no previous elevated IOP history and only one went on to have a trabeculectomy. Five patients with a post injection raised IOP had a previous history of elevated IOP and two of these underwent trabeculectomy. The authors conclude that although its anti-inflammatory effect is temporary and repeated injections are often necessary, IVTA injection is an effective therapeutic option for rapid vision restoration, inflammation control, and prevention of recurrence. Long-term follow-up revealed that ocular complications such as cataract progression and IOP elevation could decrease its efficacy and repeatability.

Reference

Long-term outcome of intravitreal triamcinolone acetonide injection for the treatment of uveitis attacks in Behçet disease.
Park UC, Park JH, Yu HG.
OCULAR IMMUNOLOGY AND INFLAMMATION
2014;22(1):27-33.

Ophthalmology

Complement Factor H and Factor H-Like protein are expressed in human RPE cells
Reviewed by: Brian Ang
Vol 20 No 6
 

The role of inflammation in age-related macular degeneration (AMD) is well documented and the association of AMD with the inflammatory marker C-reactive protein (CRP) and members of the complement system underline the role of complements in AMD. Human complement factor H controls spontaneous activation of the complement cascade, protects from oxidative stress and plays a major role in regulation of the alternative pathway of complement. In this study, retinal epithelial cells (RPE), i.e. immortalised ARPE-19 as well as primary human RPE cells, were investigated for expression of factor H and FHL-1 by immunohistochemistry and in situ hybridisation analysis. Factor H and FHL-1 are expressed in RPE cells and their expression was induced in a dose-dependent manner in ARPE-19 cells upon treatment with the inflammatory marker interleukin-6 (IL-6). Local synthesis of complement regulators affects the protection of retinal cells and may be involved in the pathogenesis at the RPE-choroid interface in AMD.

Reference

Human Complement factor H and Factor H-like protein 1 are expressed in human retinal pigment epithelial cells.
Weinberger AWA, Eddahabi C, Carstesen D, et al.
OPHTHALMIC RESEARCH
2014;51(2):59-66.

Ophthalmology

Randomised trial of multifocal intraocular lens versus monovision
Reviewed by: Brian Ang
Vol 20 No 6
 

The authors report on a randomised, multicentre clinical trial comparing the outcomes of Tecnis ZM900 diffractive multifocal intraocular lenses (IOL) versus monovision with Akreos AO monofocal IOL (dominant eye targeted for emmetropia and non-dominant eye targeted for -1 to -1.50 dioptre myopia). A total of 212 patients with bilateral cataract and no other ocular pathology were randomised to either multifocal IOL or monovision. One hundred and eighty-seven patients (88%) returned for assessment four months after surgery. There was no significant difference between the two groups in terms of binocular distance visual acuity. However, the multifocal IOL group performed worse for intermediate distance vision, and the monovision group performed worse for near vision. More patients in the multifocal IOL group achieved spectacle independence (71.3%) compared to the monovision group (25.8%). Patients in both groups were highly satisfied with their visual outcomes, but the multifocal IOL group had higher levels of symptomatic dysphotopsia symptoms. In the first postoperative year, six patients (5.7%) in the multifocal IOL group underwent IOL exchange (four bilateral; two unilateral) mainly due to dissatisfaction with image quality. No patient in the monovision group underwent IOL exchange. This is a well-conducted randomised clinical trial, which confirms both the benefits and disadvantages of multifocal IOLs compared to monovision.

Reference

Randomized trial of multifocal intraocular lenses versus monovision after bilateral cataract surgery.
Wilkins MR, Allan BD, Rubin GS, et al.
OPHTHALMOLOGY
2013;120:2449-55.

Ophthalmology

Therapeutic ocular surface medium for persistent corneal epithelial defect
Reviewed by: Brian Ang
Vol 20 No 6
 

Corneal ulcers and persistent epithelial defects (PEDs) are caused by a variety of different insults to the cornea, which includes limbal epithelial stem cell failure. PED may be resistant to healing with standard therapy such as frequent ointments and / or lubricants, particularly if there is coexistent ocular pathology. This study investigates the efficacy of therapeutic ocular surface medium (TOSM), a potential physiological tear replacement therapy, for persistent epithelial defects. TOSM is a manufactured serum substitute designed specifically to culture epithelial cells in the laboratory. It contains many essential tear components, such as growth factors. Eleven eyes of 10 patients with persistent epithelial defects (two weeks plus) without improvement with conventional therapy were enrolled in this prospective study of TOSM over one month. Healing of the PED occurred in three out of 11 eyes at one, two and four weeks respectively. At week four, two eyes were almost healed. In four of the remaining eyes, the PED area was reduced. One patient with end-stage ocular cicatricial pemphigoid with severe dry eye failed and one withdrew from the study due to mild allergic reaction.

Reference

Clinical study of therapeutic ocular surface medium for persistent epithelial defect.
Watson SL, Geerling G, Dart JKG.
OPHTHALMIC RESEARCH
2014;51(2):82-6.

Orbit

A retrospective study of the use of Dermis Fat Grafts for orbital volume augmentation
Reviewed by: Konal Saha
Vol 20 No 6
 

The authors describe the outcomes of 173 primary Dermis Fat Grafts (DFGs) and 66 secondary DFGs. Median follow-up for the primary group was 21.5 months and 14 months for the secondary group. Outcome measures included: prosthesis motility, prosthesis fit, patient / parent satisfaction and complications. After primary DFG motility was deemed excellent in 76%, patient satisfaction was excellent in 83% and prosthetic fitting excellent in 81%. After secondary DFG these results fell to: 34%, 57% and 49% respectively. The most common major complication following primary or secondary DFG was graft atrophy (3.5% after primary and 6.1% after secondary). The authors conclude that DFG is a useful option for augmenting orbital volume. The technique may have significant benefit in areas where allograft implants are not available or where implant infection may be a significant risk.

Reference

Dermis fat grafts as primary and secondary orbital implants.
Nentwich MM, Schebitz-Walter K, Hirneiss C, Hintschich C.
ORBIT
2014:33(1);33-8.

Orbit

Prognosticating ocular adnexal lymphoma
Reviewed by: Konal Saha
Vol 20 No 6
 

The authors retrospectively analyse 160 patients with primary ocular adnexal lymphoma to determine the accuracy of prognosis based on the Ann Arbor classification and how this compares to the accuracy of prognosis based on retrospectively applying the newer Tumor, Node, Metastasis (TNM) based classification system. The authors conclude that the TNM-based classification is more accurate in predicting prognosis, with bilaterality of disease, positive lymph nodes and / or metastases being important predictors of a poorer prognosis. These factors are recorded in the TNM classification but not the Ann Arbor classification. There is a significant potential confounder, with the treatment for the different stages of ocular adnexal lymphoma, based on the Ann Arbor classification influencing their prognosis, hence, invalidating the retrospective application of the TNM classification. The authors suggest a simplified version of the TNM classification. If patients are split into three groups: 1. unilateral disease, 2. bilateral or positive lymph node or metastasis, 3. bilateral with positive lymph node or metastasis; the following prognosis can be estimated (10 year progression free survival): group 1 – 75%, group 2 – 50%, group 3 – 0%.

Reference

Comparison of American joint committee on cancer TNM-based staging system (7th edition) and Ann Arbor classification for predicting outcome in ocular adnexal lymphoma.
Rath S, Connors JM, Dolman PJ, et al.
ORBIT
2014;33(1):23-8.

Retina

Clinical course of vitreomacular adhesion managed by initial observation
Reviewed by: Nikolaos Georgakarkos
Vol 20 No 6
 

The purpose of this study was to investigate the clinical course of patients with idiopathic vitreomacular adhesion (VMA) with a noncomparative case series of patients who had clinical symptoms and spectral-domain optical coherence tomography findings consistent with VMA. The VMA was graded based on the optical coherence tomography findings at initial and follow-up examinations. Grade 1 was incomplete cortical vitreous separation with attachment at the fovea, Grade 2 was the Grade 1 findings and any intraretinal cysts or clefts, and Grade 3 was the Grade 2 findings and the presence of subretinal fluid. Results: 106 eyes of 81 patients were identified as having VMA by spectral-domain optical coherence tomography with mean age at 73 years and the mean time of follow-up was 23 months. Forty-three eyes (41%) had Grade 1 VMA, 56 eyes (52%) had Grade 2 VMA, and seven eyes (7%) had Grade 3 VMA. By the last follow-up, spontaneous release of VMA occurred in 34 eyes (32%), and pars plana vitrectomy was performed in five eyes (4.7%). Mean best corrected visual acuity was 0.269 logarithm of the minimum angle of resolution or 20/37 at baseline (range, 20/20–20/200) and logarithm of the minimum angle of resolution 0.251 or 20/35 at the last examination (range, 20/20–20/400). The study concluded that in this selected patient cohort with mild symptoms, the clinical course of patients with VMA managed by initial observation was generally favourable.

Reference

Clinical course of vitreomacular adhesion managed by initial observation.
Vishak J, Flynn H, Smidy W, et al.
RETINA
2014;34:442-6.

Strabismus

Autistic responses to plusoptix photoscreening
Reviewed by: Fiona Rowe
Vol 20 No 6
 

The authors sought to determine if the plusoptix would provide an accurate estimation of whether an autistic child had amblyopic risk factors. This retrospective study identified 48 children with autism. Undilated plusoptix was undertaken in 25 children aged less than one year up to 15 years (average six). Amblyopic risk factors were found in 17 children (68%): nine with refractive amblyopia, four with accommodative esotropia, two with exotropia, one with Duane’s retraction syndrome and one with partially accommodative esotropia. Plustopix had sensitivity of 88%, specificity of 87%, false positive of 18%, false negative of 12%, positive predictive value of 94% and negative predictive value of 78%. Plusoptix
was found to be useful for screening children with autism.

Reference

Evaluation of plusoptix photoscreening during examinations of children with autism.
Singman E, Matta N, Fairward A, Silbert D.
STRABISMUS
2013;21:103-5.

Strabismus

BV after long-standing exotropia
Reviewed by: Fiona Rowe
Vol 20 No 6
 

Pre and postoperative binocular vision (BV) was compared in long-standing large angle exo deviations. The purpose was to determine the BV potential in these cases and particularly for those at risk of postoperative paradoxical diplopia. In this retrospective study patients were grouped according to preoperative BV status. Group A had evidence of BV preoperatively with normal retinal correspondence. Group B had suppression on all tests. Group C had abnormal retinal correspondence. Twenty patients were identified with eleven in group A, five in group B and four in group C. Fusion and / or stereopsis was present in 17 cases postoperatively. The results demonstrate that constant large angle long-standing childhood onset strabismus does not preclude obtaining binocular potential postoperatively.

Reference

Binocular vision outcomes following surgery for long-standing large angle exodeviations.
Gill LK, Arnoldi K.
STRABISMUS
2013;21:123-6.

Strabismus

TAC testing in dementia
Reviewed by: Fiona Rowe
Vol 20 No 6
 

The aim was to assess the visual acuity measurements performed by the preferential looking method using Teller acuity cards (TAC) in elderly subjects with dementia due to probable Alzheimer’s disease. The mean age was 78.2±9.11 years for patients and 77.2±6.19 years for controls. Controls consisted of older volunteers with no cognitive decline and all aged over 65 years. Patients had a mean MMSE score of 12.15±7.29 versus 27.3±3.07 for controls which was significantly different. Visual acuity was tested with recognition Lea symbols and with TAC. Visual acuities with both measures were well correlated. The authors propose the use of TAC as a viable alternative method for assessment of acuity in dementia patients who may not be able to perform traditional recognition acuity tests.

Reference

Assessment of visual acuity in patients with dementia using Teller acuity cards.
Froiman PC, Dantas PEC.
STRABISMUS
2013;21:93-7.

Acta Ophthalmologica

Ocular characteristics in Marfan syndrome
Reviewed by: Nana Theodorou
Feb/Mar 2014 (Vol 20 No 5)
 

Marfan syndrome (MFS) is a genetic disorder with clinical manifestations associated with cardiovascular, ocular and skeletal organ systems. Typical signs are descending aortic root aneurysms, ectopia lentis, tall stature and scoliosis. This observational study looked at the ocular characteristics, visual acuity and biometric values of 102 eyes in 51 patients with MFS. The mean patient age was 39 years (range, 12.7–71.6). Seventy-seven eyes were phakic, five aphakic and 20 pseudophakic. Thirty-one eyes had ectopia lentis, 12 cataract, nine strabismus, five glaucoma and four had undergone surgery for retinal detachment. Ninety-two per cent eyes had a best spectacle-corrected vision of 0.3 logMAR or better. In the 77 phakic eyes, myopia exceeding −3 D was seen in 39% eyes with ectopia lentis, and in 26% eyes without ectopia lentis. The mean axial length (AL) was 24.73mm and abnormally increased AL (≥24.5mm) in 51% eyes. No significant difference was found in refraction, axial length or corneal curvature between eyes with and without ectopia lentis. The authors conclude that in addition to ectopia lentis, increased axial length and a flattened cornea are typical characteristics in MFS. High myopia was not as common in MFS as expected because of a flat cornea

Reference

A descriptive study of ocular characteristics in Marfan syndrome.
Konradsen TR, Zetterström C.
ACTA OPHTHALMOLOGICA
2013;91:751-5.

Acta Ophthalmologica

Visual impairment in patients with glaucoma
Reviewed by: Nana Theodorou
Feb/Mar 2014 (Vol 20 No 5)
 

This retrospective observational study assessed the prevalence of end-of-life visual impairment in patients with glaucoma. A total of 122 deceased patients followed for glaucoma were included and data was collected from patient notes. Sixty-one patients had open-angle glaucoma and 61 patients were suspect for glaucoma or had ocular hypertension. The mean age at death was 82 years with a mean previous follow-up of nine years. Seventy-three per cent of all patients had their last visit in the year preceding death. Visual impairment was defined as a mean deviation value <−15 dB or a Snellen visual acuity <0.3 (20/60) of the better eye. For patients with open-angle glaucoma, 26% had an end-of-life visual impairment and in 15% this was caused by glaucomatous disease due to loss of visual acuity in 16%. This was mainly explained by ocular comorbidity, and there was an equal contribution of comorbidity and glaucoma in one case. Eight per cent of the glaucoma suspects or patients with ocular hypertension were visually impaired at death and these were all caused by ocular comorbidity. The authors conclude substantial visual loss at baseline is an important contributing factor.

Reference

Prevalence of end-of-life visual impairment in patients followed for glaucoma.
Ernest PJG, Busch MJWM, Webers CAB, et al.
ACTA OPHTHALMOLOGICA
2013;91:738-43.

British Journal of Ophthalmology

Mid-term evaluation of the new Glaukos iStent
Reviewed by: Jonathan Chan
Feb/Mar 2014 (Vol 20 No 5)
 

This is a prospective non-randomised interventional study to assess the efficacy and safety of the Glaukos GTS-400 iStent combined with cataract surgery. The patients enrolled in the study had cataract and primary open angle glaucoma, pseudoexfoliation glaucoma or ocular hypertension. A total of twenty patients were enrolled in the study, with an average age of 75.1±8.6 years. After the phacoemulsification and intraocular lens (IOL) placement, two GTS-400 iStents were implanted through the clear corneal incision (~2.85mm) placed for phacoemulsification. A Swan-Jacob gonioscope was used for the insertion at the nasal part of the trabecular meshwork. Post-operative visits were scheduled for one day, one week, three months, six months and one year. Three patients received one iStent for logistic reasons. The mean IOP with medication was 19.95±3.71mmHg and after washout of anti-glaucoma drops was 26±3.11mmHg. At the end of follow-up the mean IOP was 16.75±2.24mmHg, determining a final IOP reduction of 35.68% (p<0.001). At baseline, the mean number of glaucoma medications was 1.3, with a range of zero to two medications. At the final visit, the mean number of medications use had fallen to 0.3 (p<0.001). Fifteen subjects (75%) required no ocular hypertensive medication. One year after surgery, complete success was achieved in 10 of the patients (50%), while relative success was recorded in 19 of 20 patients (85%). Complete success was defined as IOP reduction to <18mmHg without medication; relative success was defined as IOP reduction to <18mmHg with medication or to <21mmHg without medication. Transient IOP elevation to above 30mmHg was observed in three eyes one day post-operatively, probably due to the persistence of viscoelastic. By the one week visit this transient IOP elevation had resolved in all three eyes. The authors concluded that combined cataract surgery with GTS-400 iStent implantation seems to be an effective and safe procedure.

Reference

Mid-term evaluation of the new Glaukos iStent with phacoemulsification in coexistent open-angle glaucoma or ocular hypertension and cataract.
Arriola-Villalobos P, Martínez-de-la-Casa JM, Díaz-Valle D, et al.
BRITISH JOURNAL OF OPHTHALMOLOGY
2013;97:1250-5.

British Journal of Ophthamology

Morning glory syndrome associated with PHPV
Reviewed by: Jonathan Chan
Feb/Mar 2014 (Vol 20 No 5)
 

This is a retrospective review of the medical records of 85 eyes / 74 patients diagnosed as morning glory syndrome (MGS) in the clinic between November 2009 and November 2012. Twenty two eyes of 19 patients diagnosed as having MGS associated with persistent hyperplastic primary vitreous (PHPV) were included in this study (25.88% of all the MGS eyes). Microphthalmia was diagnosed if the axial length of the eye was less than at least two standard deviations (SDs) below the mean for the age of the patient. All patients were recommended to have cranial magnetic resonance imaging (MRI) and MR angiography (MRA) or computerised tomography (CT) scan. Only eight patients underwent examinations due to financial constraints. Nineteen of 22 eyes (86.36%) had associated findings including cataracts (10 eyes), secondary glaucoma (eight eyes), corneal leucoma or oedema (eight eyes), retinal detachment (eight eyes), strabismus (three eyes) and nystagmus (two eyes). Lensectomy and / or vitrectomy were performed in patients with complications of glaucoma, cataract and retinal detachment by the same retinal surgeon. Of eight patients who had cranial MRI/MRA or CT examination, three patients showed abnormalities; one patient was found to have widening of the cerebral fissures of the bilateral temporal lobes, one patient showed an abnormal dilated branch of the middle cerebral artery in the left hemisphere and the other patient showed an abnormal signal in the grey matter of the frontal and occipital lobes. The authors postulated that there might be the coexistence of a genetic link between the PHPV and MGS.

Reference

Clinical characteristics and treatment of 22 eyes of morning glory syndrome associated with persistent hyperplastic primary vitreous.
Fei P, Zhang Q, Li J, Zhao P.
BRITISH JOURNAL OF OPHTHALMOLOGY
2013;97:1262-7.

British Journal of Ophthamology

Clinical evaluation of a multifocal aspheric diffractive intraocular lens
Reviewed by: Jonathan Chan
Feb/Mar 2014 (Vol 20 No 5)
 

This is a multi-centre prospective study involving five different centres in Europe including 52 patients with cataract. The average age was 68.5±10.5 years, 35 females were bilateral implanted with aspheric diffractive multifocal lens implantation of the Tecnis 1-Piece multifocal intraocular lens (IOL), model ZMB00. This is a one piece acrylic foldable posterior chamber lens with and near add of +4D with a ‘C’ loop haptic, designed to be implanted in the capsular bag following phacoemulsification cataract extraction. The lens is made of ultraviolet absorbing hydrophobic acrylic material and has a 6.0mm optic and overall length of 13.0mm. All patients were assessed with a questionnaire regarding the visual symptoms and the satisfactions and corrections of the visual requirement. This was carried out approximately four to six months after the completion of the surgery, including the uncorrected, best corrected distance and near visual acuity, under photopic and mesopic lighting, reading ability, defocus curve testing and ocular examination for complications. All patients underwent cataract surgery under topical anaesthetic, using extended suture microincision phacoemulsification technique. The intraocular lens was implanted into the capsular bag with an injection system. Postoperatively, topical therapy included a combination of antibiotics and steroidal agents were used. The second eye was performed within six weeks of the initial operation. The residual refractive error was 0.01±0.47 D with 56% of the eyes within ±0.25D and 97% within ±1D. The uncorrected visual acuity was 0.02±0.1 logMAR at distance and 0.15±0.3 logMAR at near. It only reduced to 0.7±0.1 logMAR at distance and 0.21±0.25 logMAR at near in mesopic conditions. The defocus curve showed a near addition between 2.5 and 3.0 D, allowing a reading acuity of 0.08±0.13 logMAR with a range of clear vision of less than 0.3 logMAR of approximately 4.0D. The average reading speed was 121.4±30.8 words per minute. Spectacle independence was 100% for distance and 88% for near, with high levels of satisfaction reported. The overall rating for vision without glasses could be explained by preoperative best-corrected distance acuity, postoperative reading acuity and postoperative uncorrected distance acuity in photopic conditions (p<0.001). Four patients (8%) reported glare at night and two different patients (4%) noted glare symptoms during the day. One patient had cystoid macular oedema in one eye which resolved with steroid treatment within three months and one patient had conjunctival hyperaemia and photophobia caused by dry eyes which resolved with anti-inflammatory drugs. The authors conclude that the ZMB00 1-piece Tecnis multifocal IOL provides a good visual outcome at near and distance with minimal adverse effects.

Reference

Clinical evaluation of a multifocal aspheric diffractive intraocular lens.
Schmickler S, Bautista CP, Goes F, et al.
BRITISH JOURNAL OF OPHTHALMOLOGY
2013;97:1560-4.

British Journal of Ophthamology

Secondary intraocular lens implantation in children
Reviewed by: Jonathan Chan
Feb/Mar 2014 (Vol 20 No 5)
 

This is a retrospective study of the medical records of children under the age of 16 who underwent secondary lens implantation for aphakic corrections after previous congenital cataract surgery over a period between January 2000 and December 2010. The study analysed the outcome of refraction, prediction error (PE) and factors affecting PE in children with aphakia were evaluated in this study. In total 174 eyes of 104 children between the age of 6.08±3.75 years were analysed. The mean value of PE was 1.6 dioptres (range -3.25 to 7.5D) and mean absolute PE was 2.15 (range 0-7.5D) at three months. The younger and uncooperative children had the keratometer readings measured under anaesthetic intraoperatively using a Nidek KM 500 handheld keratometer and the axial length was measured with a contact A-scan with OcuScanRxP. All intraocular lens power calculations were performed using a Sanders-Retzlaff-Kraff (SRK) II formula. It was found that the absolute PE was statistically significant between eyes with the intraocular lens (IOL) implantations calculated with the IOL master (1.8±1.40D) versus IOL calculation under anaesthesia with contact method (2.43±1.83D), p=0.01. Multiple regression analysis showed there is an inverse relationship between a secondary intraocular lens implantation and mean absolute PE (p=0.01). The surgical technique was standardised to a superior scleral tunnel technique and a polymethylmethacrylate (PMMA) IOL was used or alternatively clear corneal incisions for acrylic foldable (three piece) IOLs were inserted. A paracentesis site was situated at 10 and 2 o’clock positions for the removal of the re-proliferative lens material. The authors concluded that SRK II formula intraocular power calculations with sulcus placement gives more favourable refractive outcomes for the placement of intraocular lens implants. Although the age base refraction was targeted, a significant PE may be expected from the calculation.

Reference

Refractive outcome and prediction error following secondary intraocular lens implantation in children: a decade-long analysis.
Shenoy BH, Mittal V, Gupta A, et al.
BRITISH JOURNAL OF OPHTHALMOLOGY
2013:97:1516-9.

Clinical and Experimental Ophthalmology

Mitomycin C versus 5-FU as an adjunctive treatment for trabeculectomy
Reviewed by: Anjali Gupta
Feb/Mar 2014 (Vol 20 No 5)
 

Antifibrotic agents are used during trabeculectomy (TRAB) to improve long-term surgical success by reducing fibrosis of subconjunctival and episcleral tissue. The purpose of this meta-analysis was to directly compare the efficacy and safety of the two most frequently used antifibrotic agents, Mitomycin C (MMC) vs. 5-FU, when used as adjunctive therapy for TRAB. A systematic review was performed in April 2011. All randomised controlled trials (RCTs) comparing 5-FU directly with MMC were eligible for inclusion. Other inclusion criteria included age ≥18 years, glaucomatous optic disc features and intraocular pressure (IOP) ≥21. Five RCTs met the inclusion criteria, totalling 416 participants. MMC was associated with a statistically significant lower mean IOP level following TRAB than 5-FU (-2.17mmHg; 95%CI -3.26 to -1.08, P<0.001). Subgroup analysis revealed that a significant efficacy benefit was observed with high dose adjuvant MMC (>0.2mg/ml) compared with adjuvant 5-FU but no significant difference was observed between low dose adjuvant MMC (≤0.2mg/ml) compared with adjuvant 5-FU. There was no significant difference in the occurrence of wound leak, persistent hypotony, endophthalmitis, choroidal effusion and decrease in visual acuity of more than two lines between MMC and 5-FU. The MMC group experienced a significantly lower incidence of postoperative corneal epithelial defects than the 5-FU group (4/111 [3.6%] vs. 13/109 [12%] participants; P=0.021). The authors conclude TRAB with MMC is associated with higher rates of surgical success and is not associated with increased postoperative complications compared with TRAB with 5-FU.

Reference

Mitomycin C versus 5-fluorouracil as an adjunctive treatment for trabeculectomy: a meta-analysis of randomized clinical trials.
De Fendi LI, Arruda GV, Scott IU, et al.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2013;41:798-806.

Cornea

Corneal keloid: Report of natural history and Outcome of Surgical Management in Two Cases
Reviewed by: Sharmina Khan
Feb/Mar 2014 (Vol 20 No 5)
 

Corneal keloids are rare and typically reported following trauma (including post-surgical) and has been reported without any trauma or previous surgery. A corneal keloid differs from a hypertrophied scar in that it occurs months/years after the injury, enlarges over time and extends beyond the orders of the original traumatized tissue. They are typically solitary, firm, elevated and well-demarcated from the normal tissue. The authors report two cases with no trauma/surgical history. Case 1 was that of a 21 year old Caucasian man with a five year history of enlarging white opacity on the central cornea, OCT showed only anterior stromal involvement with a defined plane. His uncorrected visual acuity was 20/70 and BCVA 20/20. Superficial keratectomy (SK) was carried out followed by recurrence which was treated with two further SK and PTK with topical Mitomycin 0.02%. Further recurrence confined to the diameter of the excimer laser ablation required a DALK (Femto assisted). Eight months post-op his BCVA was 20/25. Histology showed irregular epithelium overlying anterior lamellar stromal scarring and thick collagen bundles associated with exuberant fibroblastic proliferation consistent with corneal keloid. Case 2 was that of a 24 year old African American man presenting with bilateral corneal opacities which were present since the age of seven and grew dramatically in the preceding two years. He underwent bilateral SK at the age of nine years with rapid recurrence. At the age of 13 he underwent PK in the left eye with dense recurrence two weeks post-operatively. He became legally blind for 11 years and developed sensory deprivation nystagmus and underwent Boston K pro type 1 (for blinking eye with no cicatrisation or lid abnormalities) including intra-operative lensectomy and vitrectomy. Three months post-operatively his uncorrected VA was 20/20 with recurrence to the edge of the keratoprosthesis titanium front plate. Histology showed coarse collagen bundles, granulation tissue and fibroblasts consistent with corneal keloid. Keloids have also been described congenitally in association with Lowe’s syndrome. The differentials are Salzmannoid nodular degeneration, Peter’s anamoly and fibrous hystiocytoma in addition to conditions causing diffuse corneal oedema. Histology usually shows a thickened corneal epithelium, overlying an anterior stroma with irregularly arranged collagen bundles, with activated fiboblasts and myofibobalsts which later become hyalinised collagen. Hypertrophied scar tissue involves subepithelial tissue and the collagen bundles are less haphazard and less hyalinized. Some have hypothesized that keloids and hypertrophic scars represent successive stages of the same condition driven by an inflammatory process. It is interesting to note that the front plate of the Boston K-pro type 1 appears to have halted the margin of recurrence in the second case and the authors comment that this should be considered as the primary corneal procedure in such cases. It would certainly be worth considering following recurrence after repeat SKs as an alternative to a penetrating or lamellar keratoplasty.

Reference

Corneal keloid: Report of natural history and Outcome of Surgical Management in Two Cases
Bakhtiari P, Agarwal DR, Fernandez AA, Milman T, Glasgow B, Starr CE, Aldave AJ.
CORNEA
2013;32(12):1621-4

Cornea

Fellow eye comparison of DMEK and PKP
Reviewed by: Sharmina Khan
Feb/Mar 2014 (Vol 20 No 5)
 

This retrospective analysis of 11 patients who underwent penetrating keratoplasty (PKP) in their first eye followed by descemet membrane endothelial keratoplasty (DMEK) in their second eye studied visual and refractive outcomes. Intra and postoperative complications were compared and a subjective questionnaire to evaluate patient satisfaction is reported. In all cases the indication for surgery was Fuchs’ endothelial dystrophy. Visual acuity (VA) improved compared to preoperatively in both groups but in the DMEK group was significantly higher at the last follow-up. The mean manifest spherical equivalent and manifest cylinder were higher in those who underwent PKP than those who underwent DMEK. Eyes that underwent PKP demonstrated higher levels of higher order aberrations than DMEK patients. In terms of complications five cases of DMEK required additional intracameral air injection. In one case of DMEK there was raised intraocular pressure (IOP) one day post op. In two eyes with PKP resuturing was required and in one case a suture was placed for high astigmatism. In the questionnaire survey nine out of 11 patients evaluated their visual outcome post-surgery as being superior in the DMEK eye than the PKP eye. Visual outcomes were graded significantly higher. Four patients stated DMEK was more painful than PKP. There was no statistical difference in pain scores between the two procedures. Two patients complained of no significant improvement in VA after undergoing PKP. Mean patient satisfaction was significantly higher in the DMEK eyes as the mean recovery period was significantly greater in the PKP group. Ten out of 11 patients preferred DMEK, citing the use of general anaesthesia versus local anaesthesia as the deciding factor. The sample size is small in this study and there may be a recall bias in the patient questionnaire as the follow-up times for the two procedures are so different. However, the trend towards posterior lamellar surgery for Fuchs’ endothelial dystrophy is already set and more is being reported about the advantages. DMEK is a more challenging procedure than Descemet’s stripping automated endothelial keratoplasty (DSAEK) and most corneal graft surgeons in the UK are still doing DSAEK as the results of this are superior to PKP.

Reference

Fellow eye comparison of descemet membrane endothelial keratoplasty (DMEK) and penetrating keratoplasty (PKP).
Maier A-K B, Gundlach E, Gonnermann J, et al.
CORNEA
2013;32:1344-8.

Current Eye Research

Ginko bilboa extract affects hypoxic retinal pigment epithelial cells
Reviewed by: Khadijah Basheer
Feb/Mar 2014 (Vol 20 No 5)
 

Wet age-related macular degeneration (AMD) is characterised by choroidal neovascular membrane (CNVM) formation. It is thought that localised hypoxia within the retina results in overexpression of growth factors such as vascular endothelial growth factor (VEGF), which induces CNVM formation. VEGF expression is enhanced by hypoxia in cultured retinal pigment epithelium (RPE) and photoreceptor cells. VEGF expression increases via several mechanisms but is largely mediated by hypoxia-inducible factor-1 (HIF-1). VEGF expression in cultured hypoxic RPE cells is inhibited by the interference of HIF-1a messenger RNA (mRNA). In laser induced CNVM HIF-1a knockout mice the disruption of HIF-1a in RPE attenuated the overexpression of VEGF. Ginko bilboa extract (GBE) is already established in improving blood flow and has been widely used in a variety of disorders including dementia and peripheral vascular disease. A study demonstrated recently that GBE inhibited cell death of cultured RPE cells under hypoxic conditions. This study investigated the effects of GBE on HIF-1a and VEGF expression in cultured human RPE cells in hypoxic conditions. RPE cells were cultured into three different groups; untreated control group, hypoxic group and hypoxic group with GBE. The groups were then analysed at different time points for expression of HIF-1a and VEGF. HIF-1a and VEGF mRNA were quantified using real-time polymerase chain reaction (PCR) and nuclei using enzyme linked immunosorbent assay (ELISA). In the hypoxia group levels of HIF-1a mRNA, VEGF mRNA, HIF-1a and VEGF levels were higher compared to the control group. In addition levels of HIF-1a mRNA and VEGF mRNA were also reduced. ELISA testing showed decreased HIF-1a and VEGF protein concentrations in this group. These results are encouraging and further studies would be needed to truly determine the beneficial effects of GBE regarding AMD. This study was an in vitro experiment using cells and therefore the clinical effect of GBE should be judged carefully. It is also unclear how much GBE consumption would have an effect and caution should be taken before encouraging increasing vitamin and mineral supplements for patients, as like medicines they too have adverse side-effects.

Reference

Effects of Ginko bilboa extract on cultured human retinal pigment epithelial cells under chemical hypoxia.
Oh JH, Oh J, Togloom A, et al.
CURRENT EYE RESEARCH
2013;38(10):1072-82.

Experimental Eye Research

Enzymatic clearance of anterior chamber infiltrate in uveitis
Reviewed by: Graham Wallace
Feb/Mar 2014 (Vol 20 No 5)
 

Aqueous humour (AH) which fills the anterior chamber (AC) of the eye provides nutrients to the cornea and the lens. Clearance of cellular and particular matter from AH is necessary for good visual acuity. In part this is achieved by high turnover of AH production by the ciliary body and removal via the trabecular meshwork. Moreover, the tissues surrounding the AC, corneal epithelium, ciliary body epithelium and trabecular meshwork all have phagocytic activity. An enzyme lysosomal phospholipase A2 (LPLA2) is ubiquitously present in tissues, and particularly in phagocytic cells such as macrophages. LPLA2 is a secreted protein and is found in many extracellular fluids. In this paper, Hiraoka et al. established endotoxin-induced uveitis (EIU) by subcutaneous injection of lipopolysaccharide in rats. This leads to AC inflammation with cellular and protein infiltrate. LPLA2 activity was significantly increased in AH from rats with EIU and correlated with the extent of inflammation. There was no increase in activity in the serum or cerebrospinal fluid (CSF) of these animals. Immunohistochemistry showed that it was tissue macrophages that expressed LPLA2, and increased migration of these cells may explain the increased enzymatic activity. AH from individuals undergoing cataract surgery including some with uveitis. LPLA2 activity was greater in those patients with uveitis compared to those without. Controlling inflammation in the eye is a complex process particularly in response to infection. While the immune system is required to eliminate pathogens it can also do damage. Increased LPLA2 activity during inflammation gives another mechanism by which the processes of protection and resolution can be mediated.

Reference

Increase of lysosomal phospholipase A2 in aqueous humor by uveitis.
Hiraoka M, Abe A, Lennikov A, et al.
EXPERIMENTAL EYE RESEARCH
2014;118:13-9.

Eye

Chronic drop use and trabeculectomy on tear osmolarity
Reviewed by: John Brookes
Feb/Mar 2014 (Vol 20 No 5)
 

Ocular surface disease (OSD) is common in patients chronically treated for glaucoma. This may be related to the drug itself but often to the preservatives in the medication. Much work has been done on the most common preservative, benzalkonium chloride (BAK). The preservatives cause microbial cell destruction by disrupting the cell membrane lipids and cytoplasmic contents. The lipid-destruction properties of BAK also affect the tear lipids responsible for the stabilisation and evaporation control of the tear film; its disturbance being a major cause of dry eye. This paper describes a prospective, case-controlled study of 130 participants, including normal controls, glaucoma patients on chronic preserved anti-glaucoma medication and post-trabeculectomy patients not on medication for over six months. Compared with normal controls, both groups of glaucoma patients were more likely to have a raised tear film osmolarity (TFO), with an odds ratio of 4.43 and 2.76 respectively. Both groups of glaucoma patients were also more likely to have dry eye symptoms. The authors conclude that TFO is increased in glaucoma patients on chronic topical medications and remains elevated after trabeculectomy surgery. They suggest further studies may be warranted to determine whether dry eye is merely aggravated by or can be caused by trabeculectomy surgery. It will be interesting to see what effect the increasing use of non-preserved eye drops has on TFO and symptoms of dry eye.

Reference

Effect of chronic anti-glaucoma medications and trabeculectomy on tear osmolarity.
Lee S-Y, Wong TT, Chua J, et al.
EYE
2013;27:1142-50.

Investigative Ophthalmology and Visual Science

Glasses or not?
Reviewed by: Carmel Noonan
Feb/Mar 2014 (Vol 20 No 5)
 

In this excellent review article, the authors discuss how some hyperopes avoid strabismus but also ask why the youngest infants escape strabismus and older patients go on to decompensate. The review considers a number of related aspects and their inter-relations including: the development of accommodation, the development of vergence and the development of refractive error. The authors conclude from their review of the literature that infants have active accommodation and vergence responses established commonly by three to six months of age. However, in order to improve prevention of strabismus development, it is important to improve our understanding of how individuals manage combined accommodation and vergence motor responses and how individuals avoid development of strabismus despite presence of risk factors such as family history and refractive error.

Reference

Why do only some hyperopes become strabismic?
Babinsky E, Candy TR.
INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE
2013;54:4941-55.

Investigative Ophthalmology and Visual Science

Walking with prisms
Reviewed by: Carmel Noonan
Feb/Mar 2014 (Vol 20 No 5)
 

This study was undertaken to assess which tempero-spatial properties of gait are influenced by vertical yoked prism (VYP) wear and consider any adjustments to gait made to maintain stability both during and following VYP wear. Thirty-one healthy adults were recruited. Three prism conditions were tested: 5PD base up, 5PD base down, plano. The results showed significant changes in gait patterns while wearing base down prisms with slowed velocity, reduced cadence, shortened step length, increased double support phase and increased step tone variability. These effects were not seen in the base up condition. The only change seen for base up prisms was a narrowed step width. Many reported feeling taller with base down prisms and this could lead to fear of falling and therefore could result in moving with greater caution and hesitancy. Floor perception was of a slanting upwards and away floor with base down prisms and slanting downwards with base up prisms. No difference was seen for measures on repeated assessment after longer term wear apart from a small increase in step length.

Reference

The effects of vertical yoked prisms on gait.
Errington JA, Menant JC, Suttle CM, et al.
INVESTIGATIVE OPHTHALMOLOGY AND VISUAL SCIENCE
2013;54:3949-56.

Journal of Pediatric Ophthalmology and Strabismus

Comparison of vision screeners
Reviewed by: Fiona Rowe
Feb/Mar 2014 (vol 20 No 5)
 

The primary purpose of this study was to calibrate the various paediatric photoscreeners over a range of contact lens induced hyperopic and astigmatic anisometropia using the American Association of Paediatric Ophthalmology and Strabismus (AAPOS) criteria for anisometropic or axial astigmatism. They applied the AAPOS validation guidelines. Photoscreeners included Nikon retinomax, Suresight, MTI, Gateway DV-S20, Canon TXI, iphone 4S, Plusoptix S09, SPOT and iScreen 3000. All seven photoscreeners gave passing, normal results for emmetropia but referred both cases with contact lens induced anisometropic hypermetropia of 2D and 1.75D induced axial astigmatism. The photoscreen images, remote autorefractors and computer interpreted photoscreeners provide a near linear relationship between induced refractive error and DCC. Iphone, SPOT and iScreen over referred contact lens induced 1D spherical anisometropia. Remote autorefractors had low sensitivity at high specificity with VIPs criteria. All nine objective screeners provided results to sort cases with refractive error in the normal range from those with amblyogenic refractive errors.

Reference

Calibration and validation of nine objective vision screeners with contact lens-induced anisometropia.
Arnold RW, Davis B, Arnold LE, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2013;50:184-90.

Journal of Pediatric Ophthalmology and Strabismus

GA position of eyes
Reviewed by: Fiona Rowe
Feb/Mar 2014 (Vol 20 No 5)
 

The authors assessed eye position based on the corneal reflex position (Hirschberg test) using a standardised measurement on pictures taken at the preoperative evaluation and under general anaesthesia (GA) in 41 patients. The mean ocular deviation taken at the preoperative visit was 32.3±11.4 with alternate prism cover test at 40cms and 33.5±12.5 with Hirschbergs. This changed to 8.8±11.4 under GA. Ocular deviation change decreased as patient age increased. Change was positively correlated with preoperative ocular deviation.

Reference

Determinants of ocular deviation in esotropic subjects under general anaesthesia.
Daien V, Turpin C, Lignereux F, et al.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2013;50:155-60.

Journal of Pediatric Ophthalmology and Strabismus

Non-accidental retinal haemorrhages
Reviewed by: Fiona Rowe
Feb/Mar 2014 (vol 20 No 5)
 

The authors sought to determine whether the presence of retinal haemorrhages (RH) correlated positively to individuals who confessed to shaking (group a) compared to those who did not confess but were identified as the likely perpetrators (group b) and cases where there was no identified perpetrator (group c). Forty-eight cases were reviewed. RH were reported in 16/18 cases in group a, 12/16 for group b and 6/14 for group c. The total incidence for RH was 73%. There was no significant difference between groups for those who confessed versus those who did not but a significant difference for when the perpetrator was identified versus not. Victims with non identified perpetrators were less likely to present acutely and time may have elapsed allowing RH to recover.

Reference

Incidence of retinal haemorrhages in abusive head trauma.
Gaffer MA, Esernio-Jenssen D, Kodsi SR.
JOURNAL OF PEDIATRIC OPHTHALMOLOGY AND STRABISMUS
2013;50:169-72.

Journal of Refractive Surgery

Rotational stability of angle supported phakic IOL
Reviewed by: Amit Patel
Feb/Mar 2014 (Vol 20 No 5)
 

The authors evaluate 50 eyes of 28 patients that underwent an angle fixated phakic intraocular lens (IOL) implantation (Acrysof Cachet). All eyes had moderate to high myopia (-5.25 to-19.63 dioptres) and IOL sizing was performed as per the manufacturer’s recommendation. All eyes had digital photography to assess IOL position at 0 and 12 months postoperatively. There were no intraoperative complications. Only one eye required additional laser refractive correction. A mean IOL rotation of 11.4±15.1 (range 0 to 60) was noted at 12 months compared to the initial assessment at 0 months. IOL rotation was not associated with endothelial cell loss (which remained stable after three months postoperatively). This study shows a larger rotation than previously reported in other studies and the authors suggest that this may be due to less effective methods of rotational stability assessment by others. The authors stipulate that rotation may be related to pupil movement and accommodation and also suggest that ultrasound biomicroscopy may be useful in assessing eyes with greater IOL rotation. They conclude that this design of the cachet lens would not be suitable for toric correction due to its higher rotational instability.

Reference

Rotation stability of the cachet angle-supported phakic intraocular lens.
Kermani O, Oberheide U, Gerten G.
JOURNAL OF REFRACTIVE SURGERY
2013;29(6):390-4.

Neuro-Ophthalmology

Differential diagnosis of inflammatory optic neuritis
Reviewed by: Claire Howard
Feb/Mar 2014 (Vol 20 No 5)
 

The authors present the differential diagnosis of inflammatory optic neuritis (ON) to include multiple sclerosis, infectious optic neuritis, systemic disease and neuromyelitis optica (NMO). The features of ON for the varying aetiologies are detailed including incidence and overlap. In acute demyelinating ON, patients typically present with progressive unilateral visual loss of variable severity, usually associated with pain. Optic neuritis due to infection more frequently corresponds to neuroretinitis rather than typical ON. ON due to NMO is often more severe and bilateral in nature. ON due to systemic disease has a low incidence reported in reviewed literature. Differentiation between causes is essential for therapeutic and management decisions to be made. A study was performed on 62 patients with relapsing ON and an eight year follow-up period reported. In this group of patients with recurrent ON, two groups had a poor prognosis (high risk of NMO and chronic relapsing inflammatory ON) that may be treated early with immunosuppressive treatments.

Reference

Inflammatory optic neuritis: from multiple sclerosis to neuromyelitis optica.
de Seze J.
NEURO-OPHTHALMOLOGY
2013;37(4):141-5.

Ocular Immunology and Inflammation

Coeliac disease and anterior scleritis
Reviewed by: Saruban Pasu
Feb/Mar 2014 (Vol 20 No 5)
 

The authors present an interesting case report of recurrent anterior scleritis. Circulating IgA and IgG auto-antibodies directed against tissue transglutaminase, endomisium and gliadin are frequently elevated in patients with coeliac disease. The classic symptoms remain chronic diarrhoea, malabsorption syndromes and abdominal discomfort, but there are also rarer systemic findings, including aphthous stomatitis and dermatitis herpetiformis. There is case report evidence of an association between coeliac disease and recurrent or chronic uveitis. The patient described is a healthy 37-year-old woman who was referred to clinic for management of recurrent refractory scleritis in her right eye of unknown aetiology. Her first episode in 2007 resolved with topical steroid treatment. Her second episode a year later needed treatment with oral steroids. She was found to have normal autoimmune blood tests. In 2009 she was first seen in the clinic with recurrence of right eye pain despite being on topical treatment. She also reported recurrent gastrointestinal upset. She underwent examination and extensive testing, including normal digestive endoscopy, colon biopsy and abdominal magnetic resonance imaging. As she had become asymptomatic, tapered withdrawal of the steroid drops was planned. In 2010 she presented with a new recurrence needing high dose oral steroids. She could not tolerate methotrexate or azathioprine so was started on salazopirine. Despite this her inflammation and ocular pain remained. As she continued to complain of recurrent gastrointestinal symptoms, she was once again screened for gastrointestinal diseases in 2011 when high anti-transglutaminase IgA antibodies were found and hydrogen breath test with d-xylose was positive. She was prescribed a strict gluten-free diet, which relieved her ocular and gastrointestinal symptoms. Systemic steroids were slowly tapered and discontinued. Since starting the gluten free diet she has only had one flare of ocular pain, which she puts down to inadvertent exposure to gluten. The authors speculate that an association may be mediated by the intrascleral deposition of immune complexes leading to tissue inflammation, similar to the pathogenesis of dermatitis herpetiformis where dermal intrapapillary deposition of IgA leads to neutrophil infiltration. Coeliac disease should be considered in the differential diagnosis of scleritis associated with gastrointestinal symptoms.

Reference

Anterior scleritis and coeliac disease: a proposed association.
Keller J, Torres-Torres R, Sainz de la Maza M.
OCULAR IMMUNOLOGY AND INFLAMMATION
2013;21(5):410-2.

Ophthalmic Research

Microperimetry of subretinal drusenoid deposits
Reviewed by: Bheemanagouda Patil
Feb/Mar 2014 (Vol 20 No 5)
 

Subretinal drusenoid deposits (SDD), originally termed ‘reticular pseudo-drusen’, have recently been identified by histology and optical coherence tomography (OCT) as aggregations located in the subretinal rather than the sub retinal pigment epithelium (RPE) space. These deposits affect the amount of light reaching the deeper layers. Spectral domain OCT (SD-OCT) shows disruption of inner segment / outer segment (IS / OS) band, which has been suggested to carry prognostic implications. This study evaluates the correlation between light sensitivity and SDD as measured with microperimetry. Twenty-one consecutive patients / eyes with SDD only were included in the study along with twenty patients / eyes in the control group. The control group had early macular degeneration in at least one eye. In all cases best corrected visual acuity (BCVA), colour fundus photography, fundus autofluorescence and SD-OCT with integrated microperimetry were performed. The mean BCVA in the SDD group was 0.18±0.14 LogMAR and the mean BCVA in the control group was 0.16±0.15 LogMAR. In eyes with SDD, the overall mean light sensitivity in the central macula (4.21± 2.46 dB) was significantly reduced when compared to the control group (6.81±2.12 dB). Correlation between BCVA and mean light sensitivity in the central 7x7mm square was low in the SDD group (Pearson’s rho = 0.4, p=0.01), while it was good in the control group (Pearson’s rho = 0.7, p=0.001).

Reference

Microperimetry of subretinal drusenoid deposits.
Forte R, Cennamo G, Crecchio G, Cennamo G.
OPHTHALMIC RESEARCH
2014;51(1):32-6.

Ophthalmology

Combined anti-VEGF and PDT for wet AMD
Reviewed by: Brian Ang
Feb/Mar 2014 (Vol 20 No 5)
 

The authors report on a retrospective case series of combined anti-VEGF and photodynamic therapy (PDT) in the treatment of wet age-related macular degeneration (AMD) refractory to anti-VEGF monotherapy alone. The criteria for treatment failure of anti-VEGF monotherapy were persistent subretinal fluid or retinal thickening of more than 250 microns on OCT at every time point before PDT and a minimum of three intravitreal injections of anti-VEGF therapy over the previous seven months. All subtypes of choroidal neovascular membranes were included. Patients with subretinal fibrosis, retinal pigment epithelium atrophy, previous retinal laser, and choroidal neovascularisation not related to AMD were excluded from the study. The combined therapy consisted of intravitreal anti-VEGF injection (bevacizumab or ranibizumab) followed by half fluence PDT (300mW, 25J, 83 seconds) with verteporfin within seven days. Visual acuity improved significantly at one month and three months, and showed a trend towards improvement at six months. Retinal thickness decreased significantly at one, three and six months. The interval between treatments increased from once every 1.6 months to once every 2.7 months with combination therapy. No ocular complications were seen with combination therapy. This study, although limited by its retrospective study design and small sample size, shows promising results for the treatment of wet AMD that is non-responsive to anti-VEGF therapy. Larger scale and longer term studies are needed to investigate this further.

Reference

Combination therapy for neovascular age-related macular degeneration refractory to anti-vascular endothelial growth factor agents.
Tozer K, Roller AB, Chong LP, Sadda SV, et al.
OPHTHALMOLOGY
2013;120:2029-34.

Ophthalmology

Scheimpflug vs. OCT in measuring corneal thickness
Reviewed by: Brian Ang
Feb/Mar 2014 (Vol 20 No 5)
 

The authors report on the reproducibility and repeatability of corneal thickness measurements using three different Scheimpflug imaging cameras (Pentacam, Sirius and Galilei) and one Fourier-domain optical coherence tomography (OCT) system (RTvue-100). The rationale for this study is that corneal thickness measurements using ultrasonic pachymetry are not entirely reliable due to the requirement for contact with the cornea and dependence on operator skill. The four different instruments stated above all offer the possibility of non-contact corneal thickness measurements, not just at the centre, but also at the mid-periphery and periphery. The study was designed in a way to evaluate the intraobserver variability, interobserver variability and intersession variability for these four instruments. Sixty-six eyes from 66 healthy subjects were recruited for the study. In terms of intraobserver repeatability, interobserver repeatability and intersession repeatability, the Galilei performed best while the Pentacam performed worst. Overall, the repeatability and reproducibility was high for all four instruments at all corneal areas measured apart from the mid-peripheral superior quadrant. The authors did not compare these corneal measurements versus measurements taken by ultrasonic pachymetry, and so agreement could not be evaluated. Nevertheless, this study shows that these imaging methods can provide non-contact corneal thickness measurements that are highly repeatable and reproducible.

Reference

A comparison between Scheimpflug imaging and optical coherence tomography in measuring corneal thickness.
Huang J, Ding X, Savini G, Pan C, et al.
OPHTHALMOLOGY
2013;120:1951-8.

Ophthamology

Four year outcomes of macular degeneration treated with ranibizumab
Reviewed by: Brian Ang
Feb/Mar 2014 (Vol 20 No 5)
 

The authors report on a retrospective study of neovascular age-related macular degeneration (AMD) patients treated with a variable ranibizumab dosing regimen over a period of four years (from January 2007 to December 2011). A total of 600 treatment naïve eyes of 555 patients aged 50 years or older, vision of 0.05 or better and foveal involvement were included in the study. Upon diagnosis, three 0.5mg ranibizmuab intravitreal injections were administered at intervals four weeks apart. The third injection was followed by a clinical examination one month later. If there was activity from the neovascular AMD, intravitreal ranibizumab was administered one at a time. If there was no further activity, follow-up was scheduled four to six weeks later, and then extended to eight to 12 weeks. Patients were discontinued from treatment if there was no AMD activity after six to seven months of observation, or if there was a lack of treatment response or if vision remained persistently <0.05. As expected, the mean vision improved from 0.24 at baseline to 0.18 at four years. Overall, 408 eyes of 381 (around two thirds) patients had treatment discontinued, mainly due to poor vision (169 eyes; 28.2%) followed by inactivity (120 eyes; 20.0%). Of the 120 eyes with discontinued treatment due to disease inactivity, only 20 (16.7%) were referred back due to disease activity, by which time vision had decreased significantly from 0.38 to 0.15. A total of 7,584 injections were given, with the mean number of injections being 5.5 per year. The ocular complication rate was low at 0.2%, with serious complications occurring in only three eyes – one rhegmatogenous retinal detachment and two infective endophthalmitis. In terms of the fellow eye, one third needed treatment during the four year period. This study reaffirms the successful outcomes of ranibizumab injections for neovascular AMD in an as-required model that resembles what happens clinically in most hospitals.

Reference

A 4-year longitudinal study of 555 patients treated with ranibizumab for neovascular age-related macular degeneration.
Rasmussen A, Bloch SB, Fuchs J, et al.
OPHTHALMOLOGY
2013;120:2630-6.

Ophthamology

Modern trabeculectomy outcomes
Reviewed by: Brian Ang
Feb/Mar 2014 (Vol 20 No 5)
 

This audit was conducted by the Trabeculectomy Outcomes Group Audit Study Group to report on the efficacy and safety of current trabeculectomy surgery in the UK. This is relevant in light of the fact that the trabeculectomy outcomes presented by the UK National Trabeculectomy Survey were based on data collected 15 years ago, and thus in need of being updated. The evolution of glaucoma surgery over the past two decades has been immense, and includes the increasing use of intraoperative mitomycin C, releasable and adjustable sutures and postoperative 5-fluorouracil (5-FU) injections, which have all purportedly contributed to safer surgery with less postoperative complications. The audit looked at trabeculectomy outcomes of 428 eyes of 395 patients with primary open angle or pseudoexfoliation glaucoma. At the end of two years, the mean intraocular pressure (IOP) had reduced from 23mmHg preoperatively to 12.4mmHg. IOP of 18mmHg or less and 20% reduction of preoperative IOP was achieved without any IOP-lowering medications in 78% and with medications in 86%. Many eyes required post-trabeculectomy interventions, such as suture manipulation (43%), postoperative 5-FU injections (28%) and bleb needling (17%). The commonest postoperative complication was bleb leak (14%) followed by bleb encystment (7.7%). Hypotony (3%) was relatively uncommon, as was bleb-related infection (1%). The results of this survey confirm that with the current modern surgical techniques, trabeculectomy outcomes have improved, with better IOP control and lower rates of serious complications, although this was associated with the need for intensive proactive postoperative care.

Reference

Trabeculectomy in the 21st century – a multicenter analysis.
Kirwan JF, Lockwood AJ, Shah P, et al.
OPHTHALMOLOGY
2013;120:2532-9.

Strabismus

Impact of orthoptic re-exam in screening
Reviewed by: Fiona Rowe
Feb/Mar 2014 (Vol 20 No 5)
 

The authors evaluated whether the re-examination within the orthotic screening in children with questionable results at the first examination can reduce the number of submissions to specialists and avoid a high number of false positives. This was a retrospective study of screening data for 2010 of 7,772 children. Six thousand one hundred and twenty-six attended screening and 1,646 did not attend. Of the latter, 318 had already been examined elsewhere. Of 6,126 examined, 5,137 were negative, 562 had a positive result and were referred, 427 showed unreliable results and were invited for a second screen. At the second screen, only 120 were positive and 307 were now negative. Most were aged three years and lack of cooperation may be a contributing factor. The second screen reduced false positives

Reference

The pediatric vision screening program performed in Bolzano in 2010: significance of the orthoptic re-examination.
Bottin D, Waldhauser K, Bertelli E.
STRABISMUS
2013;21:81-4.

Strabismus

Photoscreening comparison
Reviewed by: Fiona Rowe
Feb/Mar 2014 (Vol 20 No 5)
 

The A09/S09 photoscreener contains a fixation target of flashing lights (as for the S04) plus a smiley face which is new. Concerns were raised that the smiley face may stimulate less accommodation than the S04 attention lights and therefore potentially underestimate hypermetropia. The authors sought to determine if the referral pattern of the A09 was consistent with that of the S04 using the same pre-programmed referral criteria. One hundred and thirteen children aged less than one year up to 11 years (average five years) were examined. No significant difference was found in the pass / refer pattern of results. Correlation was 0.8345. There was no significant difference for sensitivity, specificity, false positive or false negative rate between the two devices. They conclude the S04 and A09/S09 are validated and useful tools for visual screening programmes.

Reference

A comparison of the Plusoptix S04 and A09 photoscreeners.
Singman E, Matta N, Tian J, et al.
STRABISMUS
2013;21:85-7.

Strabismus

Quality of esotropia referrals
Reviewed by: Fiona Rowe
Feb/Mar 2014 (Vol 20 No 5)
 

The purpose was to examine the quality of referrals made for children with esotropia and to evaluate management offered prior to referral. This retrospective study identified 326 children with esotropia aged less than five years and referred over a period of three years. Two hundred and seven were referred by optometrists and 119 by physicians. The mean delay in referral was 17.82 months for referrals made by physicians and 24.64 months for optometry referrals which was a significant difference. Twenty-one percent of all referrals were within four months of onset of esotropia. Twenty-one percent were for infantile esotropia and 48% of these had stereopsis of 100” or better. Management for refractive error and amblyopia was not always instigated prior to referral. Where management was offered prior to referral, it was not always appropriate or adequate in more than 50% of cases. Local education and information is required to improve referrals

Reference

Quality of referrals to a pediatric ophthalmology practice in South Western Ontario.
Makar I, Kerrin M, Smith K.
STRABISMUS
2013;21:88-92.

Strabismus

Saccadic differences under cover test
Reviewed by: Fiona Rowe
 

Patients with intermittent exotropia and exophoria plus ortho subjects underwent measurement of saccadic reaction times (SRTs) to compare those occurring in one eye and those occurring with alternating cover tests (ACTs). Twenty-five subjects were studied. Results for the intermittent exotropia group showed SRTs for ACT task of 227.3±69.9ms, and for normal task of 185.4±54.1ms. Results for the exophoria group showed SRTs for ACT task of 198.45±45.3ms, and for normal task of 178.2±34.6ms. Results for the ortho group showed SRTs for ACT task of 224.2±46.5ms, and for normal task of 200.7±37.8ms. The ACT task results were significantly prolonged in all groups. In each group a significant increase in SRTs occurred for the ACT task compared to normals. Further increase was seen for the strabismus group compared to ortho. The authors propose that the influence of occlusion of the re-fixating eye on the release of fixation attention may cause the lag of response.

Reference

Saccadic reaction times in alternating cover.
Shinomiya Y, Yamada T, Suzuki K, et al.
STRABISMUS
2013;21:74-7.

Strabismus

Translucent vs. lightproof occluders
Reviewed by: Fiona Rowe
Feb/Mar 2014 (Vol 20 No 5)
 

This study investigates the change in visual acuity following occlusion in amblyopes and non-amblyopes using translucent versus lightproof occlusion of the dominant eye. Group 1 non-amblyopes consisted of 26 subjects: 16 visually normal and 10 strabismic or anisometropic subjects without amblyopia. Group 2 amblyopes consisted of 33 subjects: 14 strabismic, six anisometropic and 13 mixed amblyopes. The results indicate that the use of lightproof or translucent occlusion over the dominant eye during visual acuity testing of the non-dominant eye had no significant effect when comparing large groups of amblyopes and non-amblyopes and within each group. They found no overall detriment to using dark occlusion or improvement with translucent occlusion. However, a number of subjects in each group had an interocular effect of up to 0.15 logMAR. An increase was seen in interocular effect with eso deviations and abnormal retinal correspondence. Anisometropic amblyopia showed monocular improvement with lightproof occlusion. Strabismic amblyopia showed monocular improvement with translucent occlusion.

Reference

Interocular effect during visual acuity measurement with and without amblyopia.
Parkinson J, Sandusky H, Trembley F.
STRABISMUS
2013;21:67-73.

Acta Ophthalmologica

Density of cataract and its influence on retinal nerve fibre layer thickness
Reviewed by: Dr Nana Theodorou
Dec/Jan 2013 (Vol 20 No 4)
 

The aim of this study was to further define and model the influence of cataract on spectral domain optical coherence tomography (SDOCT) image quality and retinal nerve fibre layer (RNFL) thickness measurements. OCT quality is influenced by opacities in the optical path and cataracts in the elderly can potentially affect OCT images. The more advanced the cataract the thinner the recorded RNFL thickness. In this study, SDOCT images were taken with two different devices (3DOCT-1000 and Cirrus HD-OCT) before and after cataract surgery and compared against normal participants using artificial filters simulating a cataract effect. Forty eyes with cataract were included and OCT image quality improved significantly postoperatively as well as RNFL thickness. The measurements using the artificial filters showed a linear relation in filter induced optical density and change in RNFL thickness. The findings may have clinical implications in diagnosing glaucoma patients with known cataract using the OCT.

Reference

The relationship between the optical density of cataract and its influence on retinal nerve fibre layer thickness measured with spectral domain optical coherence tomography.
Kok PHB, van den Berg TJTP, van Dijk HW, et al.
ACTA OPHTHALMOLOGICA
2013;91:418-24.

American Journal of Ophthalmology

Cataract surgery in patients with retinitis pigmentosa
Reviewed by: Mr K C Madhusudhana
Dec/Jan 2013 (Vol 20 No 4)
 

Retinitis pigmentosa (RP) is the commonest inherited cause of retinal degeneration. Posterior subcapsular cataract (PSC) develops in 41% to 90% of these patients by age 40 years. In this retrospective study, the authors have evaluated surgical outcomes in patients with RP undergoing phacoemulsification (n=87 eyes of 47 patients). Data on best-corrected visual acuity (BCVA), lens and zonular status, use of capsular tension ring (CTR), incidence of posterior capsular opacification (PCO) and YAG laser capsulotomy, and surgical complications were recorded. Average age was 48.9 years (range, 31-78 years) with a mean follow-up period of 23.3 months. Most (97.5%) of these patients had PSC. Mean BCVA improved from 20/340 to 20/129 within three months of surgery (p<0.0001). Eyes with a preoperative vision of 20/40 to 20/200 (47 eyes) improved from a mean 20/81 preoperatively to 20/43 (p<0.0001), postoperatively. PCO occurred in 82.5% of cases while YAG capsulotomy was required in 52.5% at an average 10.8 months postoperatively. Signs of phacodonesis were seen in 18.8% of eyes. One patient developed bilateral in-the-bag intraocular lens (IOL) dislocation more than five years after surgery. The authors conclude that cataract surgery improves visual acuity in a majority of RP patients with a preoperative vision of 20/200 or better. However, patients with a preoperative BCVA of 20/400 or worse have limited visual improvement objectively, owing to the macular pathology, but still report noticeable subjective improvement. A high prevalence of zonular weakness is noted in these patients warranting careful evaluation preoperatively and to use appropriate techniques to minimise zonular stress. The placement of standard CTRs alone may not prevent late in-the-bag IOL dislocations and hence alternative means of IOL fixation should be considered in cases with advanced or progressive zonular weakness.

Reference

Cataract extraction outcomes and the prevalence of zonular insufficiency in retinitis pigmentosa.
Dikopf MS, Chow CC, Mieler WF, Tu EY.
AMERICAN JOURNAL OF OPHTHALMOLOGY
2013;156(1):82-8.e2.

British Journal of Ophthalmology

Comparison of bilateral lateral and unilateral recession resection for IXT
Reviewed by: Mr Jonathan Chan
Dec/Jan 2013 (Vol 20 No 4)
 

This is a retrospective review study of patients between the ages of three and 15 years old with the basic type of intermittent exotropia (IXT) who had strabismus surgery between January 2003 to September 2009. There were 85 patients included in the study; 38 had bilateral lateral recti recessions (BLR-rec) and 47 underwent recession resection (R&R) procedure. The inclusion criteria included: basic type IXT within 10 prism dioptres (PD) before and after 60 min monocular occlusion; between the age of three to 15 years old at the time of surgery; no previous history after surgery or Botulinum toxin injections; best corrected visual acuity in the worst eye was at least 20/40 or better and no interocular difference of visual acuity more than two lines; no anisometropia with difference of greater than 2.50D and no hyperopia or myopia greater than +6.000D spherical equivalent in either eye; largest exodeviation at either distance or near between 15 and 50PD by the prism and alternate cover test with appropriate optical correction; no coexisting vertical deviation greater than 5PD or any evidence of A or V pattern. The postoperative follow-up period was at least six months’ duration. Successful alignment was defined as esophoria / tropia, less than or equal to 5PD to exophoria / tropia, less than or equal to 8PD in primary gaze while viewing distant or near targets. The mean follow-up period was 14.8+/- 9.5 months. In the R&R group, there was a significantly high success rate versus BLR-rec group (85.1% vs 65.8%, p=0.037). The undercorrection rate was significantly lower in the recession and resection group than in the bilateral lateral recti recession group (6.4% vs 23.7%, p=0.023). There was no significant difference in the overcorrection rate between the two groups (10.5% vs 8.5%, p=1.000). The authors suggest that the limitations of the study, including the retrospective nature of the study and the sample size is relatively small. Only a minimum follow-up period of six months was included and the reliability of the study of sensory function parameters were not included because of the inability of some of the younger children who could not manage the Worth four dots test and Titmus stereo test.

Reference

Comparison of bilateral lateral rectus recession and unilateral recession resection for basic type intermittent exotropia in children.
Wang L, Wu Q, Kong X, Li Z.
BRITISH JOURNAL OF OPHTHALMOLOGY
2013;97:870-3.

British Journal of Ophthalmology

Short-term outcome after intravitreal ranibizumab injections for ROP
Reviewed by: Mr Jonathan Chan
Dec/Jan 2013 (Vol 20 No 4)
 

This is an interventional case series study of three premature babies (six eyes) with high risk prethreshold or threshold retinopathy of prematurity (ROP) with plus disease that received intravitreal ranibizumab injections for ROP. All infants received intravitreal ranibizumab injections of 0.25mgs/0.025ml (half dose of adult dosage). A 27-gauge needle was used for the intravitreal injection, 1mm from the limbus. The treatment technique required topical anaesthetic, aseptic skin and eye preparation, together with local anaesthesia and insertion of a premature lid speculum. Follow-up examination included day one and seven days after treatment and then this was followed by the first, third and sixth month, and every six months later until the age of three years old. All eyes showed complete resolution of new vessel formation after a single intravitreal injection of ranibizumab. None of the children developed any evidence of recurrence of the disease or progression during the follow-up period. No ophthalmic or other systemic side-effects were found. The authors concluded that further large scale studies of multi-centre randomised trials were required for the long-term safety efficacy of ranibizumab treatment in ROP.

Reference

Short-term outcome after intravitreal ranibizumab injections for the treatment of retinopathy of prematurity.
Castellanos MAM, Schwartz S, Garcia-Aguirre G, Quiroz-Mercado H.
BRITISH JOURNAL OF OPHTHALMOLOGY
2013;97:816-9.

Clinical and Experimental Ophthalmology

Long-term meibomian gland function following a single thermal pulsation treatment
Reviewed by: Dr Kwesi Amissah-Arthur
Dec/Jan 2013 (Vol 20 No 4)
 

Dry eyes secondary to blepharitis and or meibomian gland dysfunction, though extremely common, is an annoyingly difficult condition to treat for several patients. Part of this difficulty lies in the inability of most patients to follow intensive and often times complex eyelid cleaning instructions coupled with a large quantity of artificial tear use to improve the lipid profile of the precorneal tear film. The LipiFlow Thermal Pulsation System was designed to directly tackle meibomian gland dysfunction as this is seen as the root cause of this condition. A device that uses an insulated lid warmer, which resembles a scleral contact lens to vault the cornea and provide controlled heat to the tissues, delivers the thermal treatment. The device also has an eye cup that consists of an inflatable bladder that sits on the eyelid and pulsates to allow expression of the meibomian glands. Heat treatment with pulsation is delivered to the meibomian glands over a 12-minute period. This paper looks at the one-year results of using this new device. Thirty patients with evaporative dry eye disease with meibomian gland dysfunction and dry eye symptoms were recruited for the study, but only 18 were able to return for the one year review. The effectiveness of the device was reviewed by measuring meibomian secretion scores and tear break-up time. Dry eye symptoms were measured using the Ocular Surface Disease Index (OSDI) and the Standard Patient Evaluation of Eye Dryness (SPEED). The authors report a significant improvement in meibomian gland secretion scores from baseline measurements (4.0±3.4) to one month, which were maintained at one year (7.3±4.6; P<0.05). Baseline tear break-up time (4.9±3.0) was significantly increased at one month (9.5±6.9; P<0.05); however, this improvement was no longer evident at one year post-treatment (6.0±4.4). The improvement in symptom scores on Ocular Surface Disease Index and Standard Patient Evaluation of Eye Dryness questionnaires observed at one-month (P<0.0005) was maintained at one year (Ocular Surface Disease Index [P<0.05]; Standard Patient Evaluation of Eye Dryness [P<0.0005]). The authors found no statistically significant difference between right and left eyes, and as such they averaged them for each patient; however, they do not document if a correction was applied or not. This study suggests that it is possible with a single 12-minute treatment of thermal pulsation, to improve some symptoms of meibomian gland dysfunction for up to a year. The study does not mention the cost of the device or cost of treatment, for ophthalmologists to assess whether the cost / benefit analysis is in favour of this treatment or not. Also the authors agree that the device does not tackle all aetiological causes of dry eyes, particularly as dry eye tends to be a multi-factorial condition. There is also concern about the number of dropouts from the surgery, though the authors have made an attempt to explain what happened to the 12 patients lost to follow-up. The main question for the authors will surely be how their device compares to relatively cheap and easily available latent heat devices that are now on the market.

Reference

Long-term (12-month) improvement in meibomian gland function and reduced dry eye symptoms with a single thermal pulsation treatment.
Greiner JV.
CLINICAL AND EXPERIMENTAL OPHTHALMOLOGY
2013;41:524-30.

Cornea

Ocular lubrication versus bandage contact lens in recurrent erosion syndrome (RES)
Reviewed by: Ms Sharmina Khan
Dec/Jan 2013 (Vol 20 No 4)
 

Twenty-nine patients (eight traumatic, five epithelial basement membrane dystrophy, two idiopathic) were randomised using SPSS to either ocular lubricants or bandage contact lenses (BCLs). Only patients previously treated with ocular lubricants were included. Patients with previous surgery, laser treatment, dry eye, meibomian gland dysfunction ocular surface disease or previous refractive surgery were excluded. Patients were examined on the slit-lamp and findings recorded; their pain was scored using a visual analogue score. Patients with macro erosion were first treated with g. Chloramphenicol 0.5% 4/day for five days. Patients were examined monthly for four months, if there was resolution again at three months otherwise monthly until seven months. BCLs (Air Optix Night and Day) were replaced monthly. Lubricants used were oc. Lacri-Lube at night and carbomer gel (Celluvisc) 0.5% 4/day. Trial outcome was assessed at four months: 1) Complete resolution with no symptoms; 2) Partial resolution; and 3) No resolution. Results showed no significant difference in outcome at four months between the two treatment arms. However, there was a significant difference in time to resolution; patients on BCL achieved complete resolution at five weeks compared with nine weeks if treated with ocular lubricants. There was no significant difference in the pain scores between the two groups. There is not enough evidence based on this and other studies that routine use of BCL in early RES management is beneficial over ocular lubricants.

Reference

Randomized controlled study of ocular lubrication versus bandage contact lens in the primary treatment of recurrent erosion syndrome.
Anandan MA, Tah V, Dhingra S, Leyland M.
CORNEA
2013;32:1311-4.

Current Eye Research

Association between serum triglycerides and pan retinal photocoagulation in type 1 diabetes
Reviewed by: Dr Khadijah Basheer
Dec/Jan 2013 (Vol 20 No 4)
 

This retrospective cohort study aimed to examine whether dyslipidaemia is a risk factor for progressing to proliferative diabetic retinopathy (PDR) and consequently requiring pan retinal photocoagulation (PRP) treatment in type 1 diabetics. In previous studies including the ETDRS study an association between serum triglyceride and development of PDR in both type 1 and type 2 diabetics has been found. This study looked at the baseline blood tests for cholesterol and lipids for 218 type 1 diabetics and correlated these with how many patients went on to have PRP treatment over a period of 13 years. Patients who had active PDR at baseline were excluded from the study. The results concluded that there is an association between raised serum triglycerides and the incidence of PRP, however, after adjusting for other established risk factors this association was not statistically significant.
Dys