Evaluation of retinal nonperfusion in branch retinal vein occlusion using wide-field optical coherence tomography angiography.

Abstract

To characterize wide-field optical coherence tomography angiography (OCTA) features of retinal nonperfusion in eyes with branch retinal vein occlusion (BRVO). Automated scanning of five 12×12-mm areas of swept-source OCTA and wide-field fluorescein angiography (FA) images was performed in a consecutive case series of 27 eyes in 27 patients with BRVO in this institutional cross-sectional study. The correlation between the areas of retinal nonperfusion detected by both examinations was assessed. Panoramic images obtained in five 12×12-mm OCTA scans in eyes with retinal nonperfusion were binarized or skeletonized, and the associations between vascular parameters such as vascular density (VD) and vascular length (VL) with the wide-field FA characteristics were evaluated. The mean area of retinal nonperfusion in the OCTA images was 81.0±66.8mm2 (range, 0.0-188.8). The mean areas of retinal nonperfusion in FA and the total FA images were, respectively, 84.7±72.5mm2 (range, 0.0-221.9) and 184.1±167.7mm2 (range, 0.0-515.0). The mean VD was 27.6±3.5% (range, 19.6-33.7), and the mean VL was 12.4±8.5% (range, 5.4-31.3). Separate regression analyses of the areas of retinal nonperfusion in FA (p=0.0004, R2 =0.4627) and the total FA (p=0.0008, R2 =0.4214) images showed a significant association with the VL. OCTA images based on wide-field technologies can quantitatively evaluate retinal nonperfusion in eyes with BRVO.