Sickle cell maculopathy
Reviewed by Sofia Rokerya

This paper reports the result of a prospective study to analyse the prevalence of sickle cell maculopathy (SCM) and its associations with age, sex, genotype, proliferative sickle cell retinopathy (PSR) stage, and the impact on visual acuity (VA). This study was carried out at a tertiary centre in UK. Age, sex and VA were recorded, and spectral domain OCT and ultra-wide-field images of the macula and retina were reviewed in a consecutive series of 74 adults with sickle cell disease. The median age was 37 years (range 19-73 years) and 36 cases (48.6%) were male. SCM was considered to be present when one or both of the following features were found: stepwise retinal thinning, typically of the inner retina and located temporal to the fovea on structural OCT imaging, or a dark blue colour on the thickness map. The Early Treatment Diabetic Retinopathy Study (ETDRS) grid (composed of three concentric circles 1, 3 and 6mm in diameter) was used to record the location of the thinning. Forty of 74 patients had SCM in at least one eye (54.1%). SCM prevalence was 54.8%, 62.5%, and 25% for the HbSS, HbSC, and HbS/BThal respectively. SCM was observed in 41 (39.4%) of the eyes with PSR stages 0, 1, and 2, and in 21 (51.2%) of the eyes with PSR stages 3, 4, and 5, respectively. Mild visual impairment or worse was present in three eyes (4.8%) with SCM. (Mild VA impairment 6/12 to >6/181 eye and moderate VA impairment (6/18 to >6/60) in two eyes). The study concluded that SCM is a frequent finding in the eyes of adults with sickle cell disease. The prevalence is similar for the HbSS and HbSC genotypes. No association was found between the presence of SCM and PSR status, and SCM is not related to gender or increasing age. Despite its frequent occurrence in the posterior pole, high-contrast visual acuity for distance was typically preserved. Limitations: Study was monocentric and therefore may not be representative of cases being studied at other centres. Images were taken of the nasal and temporal retina, but no additional images were taken of the superior and inferior retina. Near vision and reading speed were not tested, although these may have been better methods to identify visual impairment.

Sickle cell maculopathy: prevalence, associations and impact on visual acuity.
Sahaka H, Saqalain M, Lott P W, McKibbina M.
OPHTHALMOLOGICA
2021;244:159-64.