Retinal Microvasculature and Visual Acuity in Eyes With Branch Retinal Vein Occlusion: Imaging Analysis by Optical Coherence Tomography Angiography

PURPOSE. To investigate microvascular changes in the superficial capillary plexus (SCP) and deep capillary plexus (DCP) in eyes with resolved branch retinal vein occlusion (BRVO) and their association with best-corrected visual acuity (BCVA). METHODS. Eighty-five eyes (82 consecutive patients) with BRVO after resolution of the macular edema were retrospectively evaluated. All patients underwent optical coherence tomography angiography (OCTA) for assessment of microvascular changes, including capillary telangiectasia, microaneurysm, and disruption of the foveal avascular zone (FAZ). The areas of vascular perfusion and FAZ in the SCP and DCP were quantitatively evaluated. Best-corrected visual acuity was measured on the same day as OCTA examination. The correlation between BCVA and OCTA findings was assessed. RESULTS. In eyes with resolved BRVO, the mean vascular perfusion areas in the SCP and DCP within a 3 x 3-mm area were 3.75 +/- 0.49 and 3.80 +/- 0.55 mm(2), respectively. The mean FAZ areas of the SCP and DCP were 0.57 +/- 0.36 and 0.76 +/- 0.38 mm(2), respectively. Better BCVA was significantly associated with a larger vascular perfusion area in the SCP (P < 0.001) and DCP (P < 0.001), and a smaller FAZ area in the SCP (P = 0.025) and DCP (P = 0.017). Stepwise multiple regression analysis revealed that the vascular perfusion area in the DCP was the most important parameter significantly correlated with BCVA (R-2 = 0.33, P < 0.001). CONCLUSIONS. Preservation of the deep retinal vasculature is crucial for better visual function in BRVO.