Visual acuity outcome and predictive factors after bevacizumab for central retinal vein occlusion

PURPOSE. To evaluate the 12-month outcome and predictive factors of visual acuity (VA) changes following bevacizumab therapy for central retinal vein occlusion (CRVO). METHODS. A total of 50 eyes from 50 patients with CRVO were consecutively included in this prospective study. Predictive factors were assessed by comparing baseline characteristics of patients classified into 3 groups: those showing a decrease in VA; those displaying a change in Early Treatment Diabetic Retinopathy Study (ETDRS) letter score between 0 and 15; and those in whom an increase in VA >= 15 letters was achieved. Baseline variables considered in the analyses of predictive factors were demographic and clinical characteristics. RESULTS. Mean baseline ETDRS letter score was 20+/-12 and mean macular thickness was 575.1+/-152.7 mu m. Mean final ETDRS letter score improved significantly, reaching 27+/-20, p=0.04, while mean macular thickness decreased significantly to 391.1+/-229.6 mu m, p<0.001. The predictive factors associated with an increase in VA >= 15 ETDRS letters were younger age (p=0.002), shorter duration of symptoms before treatment initiation (p=0.001), and a higher visual acuity pretreatment (p=0.004). The frequency of ischemic CRVO and low vision at baseline was higher among nonresponsive patients (p=0.005). CONCLUSIONS. Intravitreal bevacizumab seems to be an effective primary treatment option for macular edema due to CRVO. Its main drawback is that multiple injections are often necessary to maintain visual improvement. Early injections of bevacizumab in young patients in whom VA is relatively preserved leads to a significant improvement in VA. Ischaemic CRVO and poor baseline VA are associated with nonresponse to such therapy.