Effect of leaking capillaries and microaneurysms in the perifoveal capillary network on resolution of macular edema by anti-vascular endothelial growth factor treatment.

Abstract

To investigate the effect of leaking capillaries and microaneurysms (MAs) in the perifoveal capillary network (PCN) on the treatment of fovea-involving macular edema (ME) secondary to branch retinal vein occlusion (BRVO) by intravitreal ranibizumab (IVR) injections combined with focal, grid, and scatter laser photocoagulation. Retrospective comparative case series. The MA (+) group consisted of 12 patients with leaking MAs in the PCN and the MA (-) group contained 11 patients without. At 6 months following the initial IVR injection, best corrected visual acuity (BCVA) was evaluated as the primary outcome. Secondary outcomes included central macular thickness (CMT) and the number of IVR injections performed in a pro re nata (PRN) regimen when CMT was ≥300 µm and vision deteriorated by 0.1 logMAR or greater. Mean BCVA improved by 0.30 ± 0.25 logMAR in the MA (-) group and 0.28 ± 0.20 logMAR in the MA (+) group (both P < 0.0001). Mean CMT was reduced by 237.6 ± 221.4 µm (P < 0.0001) in the MA (-) and 158.2 ± 152.1 µm (P < 0.01) in the MA (+) group. The degrees of improvement in BCVA (P = 0.74) and CMT (P = 0.33) did not vary significantly between the groups. The mean number of additional IVR injections was significantly less in the MA (-) group than in the MA (+) group (2.2 ± 1.0 vs 3.0 ± 0.8; P = 0.04). Although leaking MAs and capillaries in the PCN did not adversely affect improvements in BCVA and CMT, these manifestations led to an increased number of IVR injections needed to sustain resolution of ME involving the fovea.