Antagonism of Vascular Endothelial Growth Factor for Macular Edema Caused by Retinal Vein Occlusions: Two-Year Outcomes

Purpose: To determine the long-term effects of intraocular antagonism of vascular endothelial growth factor (VEGF) in patients with macular edema caused by retinal vein occlusions (RVOs). Design: Prospective randomized trial. Participants: Twenty patients with macular edema caused by branch RVOs (BRVOs) and 20 patients with central RVOs (CRVOs). Methods: After the month 3 primary end point, patients were seen every 2 months and received injections of an anti-VEGF agent as needed for recurrent edema. Main Outcome Measures: Mean change from baseline best-corrected visual acuity (BCVA) at month 24 with assessment of other parameters of visual function and center subfield thickness (foveal thickness [FTH]). Results: For 17 patients with BRVO who completed 2 years of follow-up, the mean improvement from baseline in BCVA at month 24 was 17.8 letters compared with 15.6 letters at month 3. Improvement by at least 6, 3, or 2 lines occurred in 18%, 59%, and 76% of patients, respectively. The Snellen equivalent BCVA at month 24 was 20/40 or better in 10 patients. With an average of 2 injections of ranibizumab during year 2, the mean FTH at month 24 was 245.8 mu m compared with 217.1 mu m at month 3 and 481.5 mu m at baseline. For 14 patients with CRVO who completed 2 years of follow-up, the mean improvement in BCVA at month 24 was 8.5 letters compared with 12.0 letters at month 3. Improvement by at least 6, 3, or 2 lines occurred in 14%, 21%, and 43% of patients, respectively. The Snellen equivalent BCVA at month 24 was 20/40 or better in 4 patients. With an average of 3.5 injections of ranibizumab in year 2, mean FTH at month 24 was 338 mu m compared with 278 mu m at month 3 and 533 mu m at baseline. Duration of RVO >1 year at study entry and nonperfusion of perifoveal capillaries for 360 degrees correlated with reduced visual outcomes. Conclusions: Antagonism of VEGF provides substantial long-term benefit to patients with macular edema caused by RVO, but frequent injections are required in some patients with BRVO and most patients with CRVO.