Purpose: Retinal vein occlusions(RVO) are the second most common cause of visual impairment due to retinalvascular disorders, mainly as the consequence of macular edema. We evaluatedchanges in visual acuity and macular thickness at 18 months after intravitrealbevacizumab for the treatment of macular edema in patients with RVO.

Patientsand methods: Of 45 consecutive patientswith macular edema complicating RVO and treated with intravitreal injections ofbevacizumab 1.25 mg/0.05 ml, 39 were followed for 18 months after the initialinjection. Snellen visual acuity expressed in LogMar units and macular thicknessmeasured in microns by spectral domain optical coherence tomography (SD-OCT)were the outcome measures. At baseline RVO was classified into branch retinalvein occlusion (BRVO) and central retinal vein occlusion (CRVO), and in non-ischemicand ischemic, according to clinical and fluorescein angiography presentation.All patients were evaluated, treated and followed by the same physician.Wilcoxon test for paired variables, Mann Whitney for independent variables, andStudent test for continuous variables, were used for statistical analysis.

Results:Mean age was 66.8 years (SD:13.65), 57% men and 43% women; 62.5% of cases were CRVO and 37.5% BRVO. Meannumber of injections was  4.11±1.61 (range= 1-6). Photocoagulationwas performed in 25% of patients not responding to bevacizumab. At 18 months offollow-up, improvement of visual acuity (p=0.0001) and macular thickness(p=0.0009) from baseline was observed. Best visual results were obtained at first month (median=1.00  P25= 0.5 P75= 1.30) and at 9 month (median=0.8 P25= 0.5 P75= 1.20) after first injection, but no further improvement wasobserved beyond 9 months of treatment (p=0.84). No significant visual andmacular thickness differences were obtained between patients treated withbevacizumab alone (p=0.116) and bevacizumab and laser (p=0.846). No ocular or systemic side effects attributable to treatment wereobserved.

Conclusions: Bevacizumab was safe and effective inimproving visual acuity and reducing macular thickness in this series ofpatients with macular edema complicating RVO.