Results of vitrectomy in epiretinal membranes secondary to retinal vein occlusions
Reviewed by Sofia Rokerya

This retrospective, observational multicentre study investigated the anatomic and functional results of vitrectomy associated with the peeling of secondary epiretinal membranes (ERM) in patients with retinal vein occlusion (RVO) and determined the prognostic factors of surgical outcomes. Data was collected from 50 eyes of 50 patients with RVO who underwent pars plana vitrectomy (PPV) with ERM removal between July 2012 and February 2021. Medical records at different time points, including before surgery (baseline) and 1, 3, 6, 12, 24, and 36 months after surgery were obtained. Baseline demographic and preoperative characteristics included 15 females, age at RVO diagnosis of 65 ±11 years (male 62 ±10, female 71 ±9), age at PPV was 69 ±11 years (male 66 ±11, female 74 ±9), interval between RVO and PPV was 43 ±45 months and follow-up period following PPV was 17 ±16 months. Of the total cohort, 14% of patients had diabetes, 66% had hypertension and 72% had cardiovascular disorders. Visual acuity (VA) and central macular thickness (CMT) outcomes were investigated up to three years follow-up. Univariate analysis identified the predictive factors associated with functional and anatomical outcomes. The results indicated that the mean VA of 0.9 ±0.7logMAR preoperatively improved to 0.5 ±0.5logMAR after 24 months (p=0.01). Anatomically, the mean preoperative CMT was 501 ±168μm, decreasing to 348 ±108μm at month 24 (p=0.008). By 36 months, VA had improved or stabilised in 90% of the eyes, whereas CMT had been reduced by at least 20% from baseline in 80% of the eyes. A lower number of intravitreal injections (IVI) were required after vitrectomy. Poorer preoperative VA, absence of preoperative pan-retinal photocoagulation, and postoperative use of adjunctive IVI were associated with recovery of visual acuity. Higher baseline CMT and the use of preoperative dexamethasone injections were associated with an improvement in CMT. The study concluded that PPV for ERM secondary to RVO was effective in improving VA and recovering CMT for up to three years and reduced the number of IVIs. Younger age at surgery and tamponade use predicted reduced postoperative IVI needs, while internal limiting membrane (ILM) peeling conferred no additional benefits. Future, prospective studies maybe required to validate these findings. Limitations: Retrospective design, small sample size, lack of control group, patient heterogeneity and therapeutic bias regarding the need and timing for the use of post op IVT in treatment of macular oedema, and patients lost to follow-up from the mainstream (as many were followed up by local ophthalmologists.) The study did not explore specific OCT features, including continuous ectopic inner foveal layers, which can impact the prognosis. Prognostic factors were analysed only through univariate analysis due to the impracticality of multivariate analysis with the available sample size.

Anatomical, functional, and prognostic results of vitrectomy in epiretinal membranes secondary to retinal vein occlusions.
Chunga YR, Mainguy A, Chatziralli I, et al.
OPHTHALMOLOGICA
2025;248:29–39.