Materials and Methods: We retrospectively studied the patients with macular edema secondary to BRVO and CRVO, who were treated with IVB. Best corrected visual acuity (BCVA), central macular thickness and intraocular pressure (IOP) measurements before, 1 month, 4 month, 6 month, 12 month, 24 month and the last injection were recorded. Also risk factors and complications were recorded.

Results: Forty-five eyes of 45 patients (26 BRVO, 19 CRVO) were included. The mean age was 59.24±12.26 years (range, 34-82 years) and mean follow-up time was 24.36±29.09 months ( range, 4-120 months). The average injection number was determined to be 4.62±2.89 (3-16). Hypertension was the most common systemic disease (59.9%) and glaucoma was the most common eye disease (11.1%). In BRVO group after IVB both BCVA and mean central foveal thickness significantly improved (p<0.05) at each follow-up but in CRVO group, there was no statistically significant improvement of BCVA and mean central foveal thickness (p>0.05). Both BRVO and CRVO group, there was no statistically significant change of IOP (p>0.05).

Conclusion: The results indicate that specialized systemic and ocular diagnostic examinations are necessary in light of the potential risk factors. For macular edema secondary to BRVO and CRVO, IVB administered PRN seem to be more effective in BRVO patients than CRVO. Keywords : Intravitreal bevacizumab, macular edema, retinal vein occlusion