Functional and Anatomic Response of the Retina and the Choroid to Intravitreal Bevacizumab for Macular Edema

Abstract

This study evaluated the rate of change of best corrected visual acuity (BCVA), central retinal sensitivity, and retinal and choroidal thickness in patients with macular edema after intravitreal bevacizumab. This was a prospective, nonrandomized, interventional study. Thirty-four consecutive eyes (34 patients) with macular edema were included in the study. Choroidal neovascularization was present in 21 cases, stage 1 retinal angiomatous proliferation in 6 cases, branch retinal vein occlusion in 4 cases, and diabetic edema in 3 cases. Evaluation of BCVA (Early Treatment Diabetic Retinopathy Study [ETDRS] logarithm of the minimum angle of resolution [LogMAR]), central retinochoroidal thickness (RCT) at standardized A-scan, combined optical coherence tomography/microperimetric assessment of central retinal thickness (RT), central scotoma, and fixation behavior was performed during 12 months after treatment. Choroidal thickness was considered as the difference between RCT and RT. All patients received two initial intravitreal bevacizumab injections (1.25 mg/0.05 mL) at a 1-month interval. BCVA and RT during follow-up were significantly better than at baseline. BCVA was improved of 0.32±0.3 LogMAR (P<0.001) at month 1, 0.18±0.4 LogMAR (P=0.05) at month 6, and 0.14±0.2 (P=0.09) at month 12. RT was reduced by 172.9±192.8 μm (P<0.001) at month 1, 157.7±134.2 μm (P=0.003) at month 6, and 164.3±122.3 (P=0.002) at month 12. Mean retinal sensitivity significantly increased during the first month; it decreased afterward, but an improvement if compared with baseline was present at each visit during follow-up. In 23.5% of cases, a choroidal thinning was present during follow-up, and in this group visual acuity at baseline and final visual improvement were significantly greater if compared with patients showing a choroidal thickening. Intravitreal bevacizumab for macular edema determines significant functional and anatomic improvement at the 12-month follow-up. Visual acuity at baseline and following treatment could be influenced by the choroidal involvement.