Intravitreal Ranibizumab for Macular Edema Secondary to Retinal Vein Occlusion

Background/Aims: To investigate the effects of intravitreal ranibizumab treatment for macular edema (ME) secondary to retinal vein occlusion (RVO) and the relationship between spectral-domain optical coherence tomography (SD-OCT) findings and visual outcome after successful resolution of ME. Methods: Forty consecutive eyes with ME secondary to branch RVO (BRVO; 29 eyes of 29 patients) or central RVO (CRVO; 11 eyes of 11 patients) were included in a prospective study and treated with 3 initial intravitreal injections of 0.5 mg ranibizumab at monthly intervals. Retreatment was based on visual acuity changes and OCT findings. Patients with complete resolution of ME were classified into two groups according to final best-corrected visual acuity (BCVA) of better than 0.30 logMAR (group 1) or poorer than 0.30 logMAR (group 2), and SD-OCT findings were analyzed at baseline and at 12 months. Results: In patients with BRVO, mean BCVA at 12 months (0.19 ± 0.18) was significantly better than that at baseline (0.76 ± 0.37; p = 0.000). The mean number of injections was 4.4 ± 1.2. In patients with CRVO, the mean BCVA at 12 months (0.39 ± 0.23) was slightly improved from that at baseline (0.84 ± 0.68), but the difference was not significant (p = 0.063). Patients with CRVO received a mean number of 6.1 ± 1.4 injections of ranibizumab. Baseline SD-OCT more frequently detected the foveal inner/outer segment (IS/OS) line and external limiting membrane (ELM) in group 1 (p = 0.003) than in group 2 (p = 0.012). Preservation of the foveal IS/OS line (odds ratio = 5.400; p = 0.036) and ELM (odds ratio = 7.312; p = 0.016) at baseline correlated with good final visual outcome. Conclusion: Intravitreal ranibizumab injections effectively treat ME secondary to RVO. Good visual outcome was associated with preservation of the foveal IS/OS line and ELM at baseline.