Efficacy of Prophylactic Anti-VEGF in Preventing Radiation Retinopathy: A Systematic Review and Meta-Analysis.

Background: In patients predisposed to radiation retinopathy (RR), administration of therapy after apparent clinical signs and symptoms are considered too late, resulting in substantial vision loss and blindness. Early initiation of anti-vascular endothelial growth factor (anti-VEGF) might serve as a strategy to slow disease progression and prolong good eyesight. Objective: To evaluate the efficacy of prophylactic anti-VEGF in preventing RR and preserving vision in patients at high risk of radiation-induced vision loss. Methods: A systematic literature search was performed from inception to 4 June 2023 using Cochrane Library, EMBASE, PubMed (MEDLINE), and Scopus. Eligible studies were clinical trials and observational studies investigating the incidence of radiation maculopathy (RM), radiation optic neuropathy (RON), moderate vision loss (loss of more than or equal to 3 lines of baseline visual acuity [VA]) and final VA, whether good (20/40 or better) or poor (20/200 or worse), following prophylactic anti-VEGF. Three reviewers independently conducted article screening, data extraction and risk of bias assessment. Random effects models were used to determine the cumulative effects of each outcome. Results: Four studies (one clinical trial and three observational studies), involving 2109 patients, were included in our analysis. Across all studies, there were significant reductions in the events of RM (pooled odds ratio [OR] 0.50; 95% CI, 0.34-0.74; p = 0.001), RON (pooled OR 0.62; 95% CI, 0.42-0.90; p = 0.012) and poor final VA (pooled OR 0.50; 95% CI, 0.37-0.68; p = 0.003). The association of moderate vision loss and good final VA with the use of prophylactic anti-VEGF between the groups was unclear owing to the high level of heterogeneity. Conclusion: Prophylactic anti-VEGF therapy might delay RM and RON, preventing high-risk patients from developing poor VA by approximately 50%. However, this evidence should be interpreted with caution because of its low level of certainty. Future robust studies are warranted to confirm this finding.