Abstract
Purpose: :
Central retinal vein occlusion (CRVO) is a frequent retinal vascular disease in the population over 40 years old. Macular edema may cause an additional reduction in visual acuity that often exceeds the primary ischemic damage. Early treatment may be required to improve vision because longstanding macular edema results in irreversible photoreceptor damage. Bevacizumab is a full-length, humanized monoclonal antibody directed against all biologically active isoforms of VEGF-A. Often patients report of immediate improvement of visual acuity and reduction of metamorphopsia within a few days after injection. Major drawbacks of this therapy are relapses in the course of the disease so that repeated injections are necessary.In this study we were interested in the time course of the reduction of macular edema after injection of Bevacizumab. We evaluated the anatomic and visual acuity (VA) response hourly after intravitreal injection of Bevacizumab in patients with macular edema due to CRVO.
Methods: :
Five patients with macular edema (central retinal thickness (CRT > 570 µm) after CRVO were treated with intravitreal injections of 1.25 mg of Bevacizumab. The mean duration of CRVO prior to first intravitreal injection was 6 weeks. OCT-scans and examinations were performed every hour (1 to 8 hours after injection), daily for 4 days, then weekly after the injection. All patients received 3 Injections. The mean follow-up time was 12 weeks.
Results: :
A significant decrease of macular edema occurred in all patients within the first hour (mean reduction of CRT 38 ± 2.7 µm). VA improved in all patients after 24 hours (mean one line Log MAR). The maximum improvement of VA was achieved after one week and sustained for 4 -6 weeks post injection (mean 4 lines Log MAR). After 3 intravitreal injections the mean reduction of CRT was 224 µm (152-317µm). No adverse events were observed.
Conclusions: :
Our results suggest that the beneficial effect of intravitreal Bevacizumab on CRT is very rapid and occurs within the first 24 hours after injection. This effect may last for several weeks. Re-injections will be necessary to maintain a lasting improvement.
Keywords: vascular occlusion/vascular occlusive disease • edema • macula/fovea