Objective To evaluate the efficacy and safety of Ranibizumab intravitreal injection in patients with macular edema secondary to retinal vein occlusion. Methods Forty-five patients( 45 eyes) with macular edema secondary to retinal vein occlusion were given intravitreal injections of ranibizumab. During follow-up,the patients' best-corrected visual acuity( BCVA),central macular thickness( CMT,measured by using OCT),fundus findings and other complications were observed at 1 day,15 days,1 month,3 months and 6 m...