Intravitreal bevacizumab (Avastin) treatment of diffuse diabetic macular edema in an Indian population

BACKGROUND: To report the anatomic and visual acuity response after intravitreal bevacizumab (Avastin) in patients with diffuse diabetic macular edema. DESIGN: Prospective, interventional case series study. MATERIALS AND METHODS: This study included 20 eyes of metabolically stable diabetes mellitus with diffuse diabetic macular edema with a mean age of 59 years who were treated with two intravitreal injections of bevacizumab 1.25 mg in 0.05 ml six weeks apart. Main outcome measures were 1) early treatment diabetic retinopathy study visual acuity, 2) central macular thickness by optical coherence tomography imaging. Each was evaluated at baseline and follow-up visits. RESULTS: All the eyes had received some form of laser photocoagulation before (not less than six months ago), but all of these patients had persistent diffuse macular edema with no improvement in visual acuity. All the patients received two injections of bevacizumab at an interval of six weeks per eye. No adverse events were observed, including endophthalmitis, inflammation and increased intraocular pressure or thromboembolic events in any patient. The mean baseline acuity was 20/494 (log Mar=1.338±0.455) and the mean acuity at three months following the second intravitreal injection was 20/295 (log Mar=1.094±0.254), a difference that was highly significant ( P =0.008). The mean central macular thickness at baseline was 492 µm which decreased to 369 µm ( P =0.001) at the end of six months. CONCLUSIONS: Initial treatment results of patients with diffuse diabetic macular edema not responding to previous photocoagulation did not reveal any short-term safety concerns. Intravitreal bevacizumab resulted in a significant decrease in macular thickness and improvement in visual acuity at three months but the effect was somewhat blunted, though still statistically significant at the end of six months.