Abstract
Purpose: :
Intravitreal injection of the bevacizumab (Avastin) seems to be a promising therapy for macular edema (ME) secondary to BRVO. The aim of this study was to investigate the clinical and anatomic effect of bevacizumab for long-lasting ME in dependence on the angiographic characteristics.
Methods: :
28 patients with ME secondary to BRVO were treated with injections of 1.25 mg bevacizumab and classified in perfused or ischemic ME. Retreatment was made if intraretinal cysts/fluid was still detectable in ocular coherence tomography (OCT) or visual acuity decreased. Treatment was also offered if the edema was unchanged after the first injection. At regular control examinations, the patients agreed upon the discontinuation of the treatment, if the edema showed no change after two injections. At least adequate resorption of macular hemorrhages and duration of the BRVO of more than 18 months were inclusion criteria. Angiographic characteristics as well as retinal thickness parameters were evaluated in a masked fashion to the clinical data. As primary outcome central retinal thickness (CRT) and visual acuity were compared using Wilcoxon Signed-Rank test (=0.05).
Results: :
Mean age of the 26 patients (11 male, 17 female) was 67 years (range: 49 - 82). The median time between symptoms of BRVO and first bevacizumab injection was 39.8 months (range: 18-146 months). The angiographic classification before the first injection showed 9 eyes with ischemic ME and 17 patients with perfused ME. Median number of injections per eye was 2.5 (range: 1-8).Mean visual acuity (VA) impoved from 0.52 (logM) at baseline to 0.51 (logM) after the first injection (median: 7.8 weeks) and did not decrease until the final examination (median 26.3 weeks). There was a tendency that patients with an initial increase also gained letter over the longer follow-up (Pearson coefficient: 0.300, p=0.165). Median CRT before bevacizumab treatment was 390µm (95%-CI: 339-446µm). CRT decreased by the first visit to 260µm (95%-CI: 260-393µm) and the final examination (250µm, 95%-CI: 244-385µm, p=0.037). The significant anatomic response occurred independently of failed pre-treatment (Grid-Lasercoagulation, Triamcinolone).
Conclusions: :
Intravitreal injections of bevacizumab have the potential to reduce intra-retinal fluid, even in long-lasting ME secondary to BRVO. Although VA did not significantly increase, the decrease in CRT can provide relevant reduction of metamorphopsia and protection from secondary damage to photoreceptors.
Keywords: vascular occlusion/vascular occlusive disease • edema