Materials and methods: This study comprised 25 patients with branch RVO (BRVO) and 30 patients with central RVO (CRVO). Initial treatment consisted of monthly anti-VEGF injections for 6 months in BRVO and 6 to 12 months in CRVO. Subsequent treatment for patients who did not meet stability criteria was based on response to treatment.

Results: The mean follow-up time was 46 months. The mean number of injections per patient in the ?rst year was 7.7 for BRVO and 9.2 for CRVO and decreased dramatically in the years thereafter. About 67% of the eyes received anti-VEGF agents only. At the final visit, for patients with BRVO and CRVO,respectively, central subfield thickness had decreased -167 and -280 ?m, and visual acuity gain gain was 11.5 and 19.0 letters. ME had resolved in 84% of patients with BRVO and 67% of patients with CRVO. Older age (P<0.001),diabetes (P=0.01) and persistence of ME (P<0.001) limited the visual improvement in BRVO, and retinal ischemia (P<0.001) and severe disorganization of the retinal inner layers (P<0.001) after treatment limited the visual improvement in CRVO.

Conclusion: Initiating early intensive intervention with anti-VEGF during the early phase of ME can suppress recurrence in chronic phase. In the chronic phase, when the disease becomes resistant to anti-VEGF therapy, scatter laser photocoagulation may decrease the treatment burden in ischemic BRVO, and dexamethasone implant may improve cost-effectiveness in both BRVO and CRVO. Keywords : Branch retinal vein occlusion, Central retinal vein occlusion, Dexamethasone intravitreal implant, Macular edema, Vascular endothelial growth factor