Clinical observation of intravitreal Bevacizumab combined with laser photocoagulation for treatment of macular edema secondary to retinal vein occlusion

Abstract

Objective To evaluate the efficacy and safety of intravitreal injection of Bevacizumab (Avastin) combined with laser photocoagulation in the patients of macular edema secondary to retinal vein occlusion (RVO).Methods This was a retrospective cases-series study.Thirty eyes of 30 RVO patients (branch RVO 20 eyes and central RVO 10 eyes) were erolled,aged from 34 to 79,with average of (57.3±8.9)years.The eyes were treated with intravitreal injections of Bevacizumab (1.25 mg) combined with laser photocoagulation.The treatment method of intravitreal injection had been conducted according to PrONTO study.Best corrected visual acuity (BCVA,ETDRS letters),fundus photography,optical coherence tomography (OCT) were committed at baseline and 1,3,6,12 months after intravitreal injection.The ETDRS letters and the central retinal thickness (CRT) by OCT were recorded.Changes in BCVA and CRT measurements from baseline at the various follow-up endpoints were assessed with paired t test.Spearman correlation coefficient was used to measure the strength of correlation between BCVA and anatomic changes.Results The mean number of the injections in the 30 patients was 3.9±1.9.The BCVA improved 3 or more lines in 16 eyes (54％),improved 1 to 2 lines in 10 eyes (33％),stabilized (±1 line or no change) in 4 eyes (13％) and none decreased.The average BCVA at baseline was (42±19) letters,and improved to (60±19) letters at 12 months (t=7.87,P＜0.05).The average of retinal thickness of macular foveal decreased from (616.7±177.0)μm at baseline to (268.9±l15.9)μm at 12 months (t=13.23,P＜0.05).BCVA 12 months post-treatment was correlated to BCVA pre-treatment (r=0.791,P＜0.01).Macular edema had no correlation with baseline and finally BCVA.21 eyes (70％) showed no observed macular edema by the last follow-up and the side effects were not observed during the follow-up.Conclusion The persistent and rebound macular edema found in Bevacizumab treatment had some common characteristics in FFA. Combined intravitreal injections of Bevacizumab and laser photocoagulation therapy seemed to be effective for managing some refractory macular edema secondary to RVO.The Bevacizumab and photocoagulation related adverse events are rare. Key words: Retinal vein occlusion; Macular edema; Vascular endothelial growth factor A; Bavacizumb; Laser therapy