Gap in capillary perfusion and burden of treatment in branch retinal vein occlusion

To evaluate correlations between the burden of antivascular endothelial growth factor treatment and microperfusion status in superficial capillary plexus and deep capillary plexus (SCP and DCP) using wide-field optical coherence tomography angiography.A total 19 eyes with branch retinal vein occlusion were included in this retrospective study. Area of foveal avascular zone, capillary nonperfusion area, vascular density, and perfusion gap were compared between superficial capillary plexus and DCP. Internal areas of 3, 6, and 12 mm in diameter around the fovea were analyzed separately.The mean number of injections per months was 0.20 ± 0.12. The number of antivascular endothelial growth factor injections per month showed a significant correlation with perfusion gap in 12 mm area (P = 0.010), but not with perfusion gap in 3-mm or 6-mm area. Correlations were also found between the final best-corrected visual acuity and vascular density in the 12 mm area of DCP (P = 0.031) and foveal avascular zone area (P = 0.033).Wide-field optical coherence tomography angiography is very useful for assessing the microperfusion status in branch retinal vein occlusion. In extended field of view (12 mm × 12 mm), a larger perfusion gap was associated with frequent requirements of antivascular endothelial growth factor injections for macular edema. Reduction in vessel density was significantly correlated with poor visual outcome.