Long-Term Results of Intravitreal Bevacizumab Injection for Macular Edema: Retinal Vein Obstruction and Diabetic Retinopathy

Abstract

Purpose: To evaluate the long-term results of intravitreal bevacizumab injection for macular edema (ME) due to retinal vein obstruction (RVO) and diabetic retinopathy (DR). Methods: The objects of study were patients with decreased visual acuity due to ME with RVO and DR for whom intravitreal injections of 1.25 mg (0.05 ml) bevacizumab were repeated three times with an interval of six weeks and who were available for a follow-up period of more than 12 months. The patients underwent additional bevacizumab injections if ME increased as assessed by optical coherence tomography (OCT). Best-corrected visual acuity (BCVA) and central macular thickness (CMT) were measured at baseline and follow-up visits. Results: There were 16 patients with RVO and 18 patients with DR. In the RVO group, the mean length of follow-up was 12.41.1 months, the mean baseline BCVA was 0.750.32 and the final BCVA was 0.420.25, a difference that was statistically significant (p＜0.05). The mean CMT at baseline was 588.5301.0 and this decreased to a mean of 191.8 at the end of the follow-up period (p＜0.05). In the DR group, the mean length of follow-up was 15.43.2 months, the mean baseline BCVA was 0.630.33 and the final BCVA was 0.610.37, a difference that was not statistically significant (p＞0.05). The mean CMT at baseline was 462.0 and decreased to a mean of 282.2 at the end of the follow-up period (p＜0.05). Conclusions: In RVO and DR, three injections of intravitreal bevacizumab with an interval of six weeks and additional injections as indicated were effective in reducing ME and showed especially good results in improvement of visual acuity for ME due to RVO.