Purpose:
To determine the factors for predicting a favorable response to intravitreal bevacizumab (IVB) for macular edema (ME) associated with branch retinal vein occlusion (BRVO).
Methods:
Thirty-seven eyes of patients first diagnosed with BRVO-associated ME and treated with IVB more than twice were included in this retrospective case series. Baseline characteristics, initial best-corrected visual acuity (BCVA), initial central macular thickness (CMT), and change in CMT after 2 consecutive monthly IVB injections were reviewed. Patients were classified into 2 groups according to their IVB response: non-responders were defined as those in whom CMT was not decreased by greater than 10% of the initial value after 2 consecutive monthly injections. The types of observed macular edema were further subdivided into the cystoid macular edema (CME) only, serous retinal detachment (SRD) only, and combined CME and SRD groups for analysis.
Results:
Thirty-three patients were classified as responders and 4 patients were classified as non-responders. The responder group was comprised of significantly older patients than the non-responder group (63.8 ± 11.7 vs. 54.5 ± 1.0, p = 0.034). The initial BCVA of the non-responder group was significantly higher than that of the responder group (logMAR 0.08 ± 1.04 vs. 0.37 ± 0.60, p = 0.003). The anatomical type of ME did not significantly influence the response to IVB. There were no differences in the histories of diabetes mellitus or hypertension between the groups, and the existence of an epiretinal membrane did not appear to affect treatment response.
Conclusions
Patients with better initial BCVA and those who were older appeared to have a more favorable response to IVB treatment in ME due to BRVO.