Purpose: To determine the predictive values of baseline optical coherence tomography (OCT) abnormalities on 12-month visual acuity changes in eyes with macular edema (ME) caused by branch retinal vein occlusions (BRVO).
Methods: We performed a post hoc analysis of data from 75 participants in the 12-month MARVEL trial. OCT abnormalities at baseline, including ganglion cell layer cystoid spaces (GCL), intraretinal hyper-reflective dots, and central subfield thickness (CST), were correlated with improvements in visual acuity and the number of anti-vascular endothelial growth factor injections required using a multivariate regression model.
Results: Eyes with baseline CST > 500 μm had greater visual gains compared to those with CST <500 μm (+21.09 vs +16.08 letters, P = 0.04). Eyes with hyper-reflective dots (+13.97 vs +19.93 letters, P = 0.02), and GCL cysts (+9.8 vs +18.9, P = 0.003) had inferior gains in visual acuity. Neurosensory macular detachments at the baseline did not affect gains in visual acuity. Ninety percent of the gain in visual acuity was recorded after two injections and was maintained until month 12.
Conclusion: Baseline OCT of <500 μm, hyper-reflective dots, and GCL cystoid spaces are associated with poorer gains in visual acuity. Most of the visual gain occurs after two injections.
Keywords: Bevacizumab; branch retinal vein occlusion; disorganization of retinal inner layers; ganglion cell layer cystoid spaces; hyper-reflective spots; macular edema; optical coherence tomography; ranibizumab.