Can the integrity of the photoreceptor layer explain visual acuity in branch retinal vein occlusion?

In this issue of the British Journal of Ophthalmology, Ota and his associates (see page 1644)1 report that the presence of the third high reflectance band (HRB) in images obtained by optical coherence tomography (OCT) postoperatively is correlated with the visual outcome after different treatments for macular oedema secondary to branch retinal vein occlusion (BRVO). They also investigated whether the appearance of the preoperative OCT images could predict the final visual acuity. Their results indicated that the presence of the third HRB in the parafoveal area preoperatively could indeed be a predictor of the postoperative visual acuity.

Grid laser photocoagulation has been the standard treatment for macular oedema secondary to BRVO.2 However, over the past decade, more interventional therapeutic options have emerged. Vitrectomy with or without arteriovenous sheathotomy,3^–5 intravitreal triamcinolone injection6 and intravitreal injection of tissue plasminogen activator7 have been used to treat macular oedema. The efficacies of these interventions, however, are controversial because of the lack of a randomised controlled studies.8 In a previous study, the authors reported the efficacy of intravitreal tissue plasminogen activator injection,7 and also demonstrated a correlation between the presence of the third HRB and visual outcome. …