Functional and Anatomical Outcomes of Anti-VEGF Therapy
Several studies have demonstrated favorable functional and anatomical outcomes following anti-VEGF injections. Following a single anti-VEGF injection, a decrease in central macular thickness (CMT) and a modest improvement in VA. However, by 4 months' follow-up, the macular edema had recurred, and VA worsened to baseline in all 10 patients demonstrating the chronic nature of RR.

With more consistent bevacizumab injections every 6 to 8 weeks, patients achieve improvements in cystoid macular edema (CME), stabilization, and occasionally improvement in VA over a short-term mean follow-up of 4.7 months. Furthermore, clinical findings such as intraretinal hemorrhages, microaneurysms, and leakage on fluorescein angiography improved following treatment.

Larger studies have revealed that up to 86% of patients can achieve VA stabilization or improvement over short-term follow-up of 4 to 6 months with monthly injections25 and a mean of 7.8 months when receiving injections at 6- to 12-week intervals.1 Similarly, maintenance of VA within 2 lines of baseline was retrospectively noted in 80% of patients over long-term mean follow-up of 38 months when receiving continuous anti-VEGF injections.26 Likewise, favorable outcomes with VA of 20/50 or better was attained in 51% of patients at 54 months follow-up with continuous anti-VEGF therapy, further denoting the importance of prolonged therapy.26

Moreover, anti-VEGF injections for RR have been shown to reduce the enlarged foveal avascular zone on optical coherence tomography (OCT) angiography. This can potentially explain the improvements in VA experienced by patients in addition to reduction in CME. Of note, recent studies have similarly demonstrated favorable visual and anatomical outcomes for patients with RR treated with both ranibizumab. Taken together, these studies have demonstrated the importance of prompt detection of RR with early initiation and sustained continuous anti-VEGF therapy.