Predictive Factors for Functional and Anatomical Outcomes After Anti-VEGF Treatment for Macular Edema in Patients with Branch Retinal Vein Occlusion.

Purpose: This study aimed to identify predictive factors for the improvement of best-corrected visual acuity (BCVA) and reduction of central macular thickness (CMT) after treatment of macular edema (ME) due to branch retinal vein occlusion (BRVO) in a real-world setting.

Methods: This retrospective study included patients with ME secondary to BRVO who were treated with intravitreal injection of bevacizumab as the first-line therapy and were followed up for 12 months. Demographic and clinical data, in addition to baseline spectral domain optical coherence tomography (SD-OCT) features, were considered as possible biomarkers of final BCVA and CMT. We also collected the data concerning the need for additional treatment including sectorial laser photocoagulation, change to another anti-VEGF agent, or intravitreal corticosteroid injection.

Results: A total of 161 eyes were analyzed. BCVA significantly improved from baseline to 12-month follow-up (0.6 and 0.4 logMAR, respectively; P $<$ 0.01). CMT decreased significantly during the follow-up period (from 498.0 to 325.0 $\mu$ m; P $<$ 0.01). Final BCVA correlated positively with baseline BCVA (P $<$ 0.01, r = 0.57). Older age at diagnosis and baseline SD-OCT findings including CMT, disruption of the retinal inner layers, retinal pigment epithelium (RPE) damage, and impairment of the ellipsoid zone and external limiting membrane negatively affected final BCVA (P $<$ 0.01). Multiple regression analysis identified age and BCVA at baseline as the only independent predictors of final BCVA (P = 0.001 and P $<$ 0.01, respectively). No association was found between clinical data, SD-OCT parameters, and final CMT.

Conclusion: Various clinical and SD-OCT parameters are prognostically relevant for visual improvement in ME secondary to BRVO. Age at diagnosis and baseline BCVA were found to be independent predictors of visual outcome.