Background/purpose: To evaluate the effect of individualized repeated intravitreal injections of ranibizumab (Lucentis) on visual acuity (VA) and central foveal thickness (CFT) for central retinal vein occlusion (CRVO)-induced macular edema.
Methods: Our study was a prospective interventional case series. Twelve eyes of 12 consecutive patients diagnosed with CRVO-related macular edema (nine perfused, three ischemic CRVO) treated with repeated (when CFT was >220 microm) intravitreal injections of ranibizumab as a monotherapy within 3 months of onset were evaluated. Optical coherence tomography (OCT) and fluorescein angiography (FA) were performed monthly and every 3 months respectively. Changes in VA (ETDRS) and CFT were analyzed using the student's paired t-test.
Results: The mean time from diagnosis until injection was 80 days (2.7 months; range, 63-90 days) and the follow-up time was 12 months. In total, 89 injections were performed (mean 7.4). The mean CFT improved from 480 +/- 166 microm at baseline to 230 +/- 33 microm (P < 0.001) at the end of the follow-up. During the same period, of the 12 eyes, eight demonstrated improved VA (>0.3 LogMAR change, >15 letters), three stable VA and one worse VA as compared to baseline. None of the nine patients with perfused CRVO were converted to ischemic at 12 months, and one of the three eyes with ischemic CRVO developed iris neovascularization despite two ranibizumab injections. No ocular or systemic side-effects were noted.
Conclusion: Individualized repeated intravitreal injections of ranibizumab have shown promising results in VA improvement and decrease in CFT in patients with macular edema associated with CRVO. Further studies are needed in order to elucidate the role of intravitreal lucentis in the ischemic form of CRVO, and its efficacy in preventing conversion from the perfused to the ischemic form of the disease.