QUANTIFICATION OF RETINAL CAPILLARY NONPERFUSION IN DIABETICS USING WIDE-FIELD OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY.

Abstract

To combine advances in high-speed, wide-field optical coherence tomography angiography (OCTA) with image processing methods for semiautomatic quantitative analysis of capillary nonperfusion in patients with diabetic retinopathy (DR). Sixty-eight diabetic patients (73 eyes), either without retinopathy or with different degrees of retinopathy, were prospectively recruited for volumetric swept-source OCTA imaging using 12 mm × 12 mm fields centered at the fovea. A custom, semiautomatic software algorithm was used to quantify areas of capillary nonperfusion. The mean percentage of nonperfused area was 0.1% (95% confidence interval: 0.0-0.4) in the eyes without DR; 2.1% (95% confidence interval: 1.2-3.7) in the nonproliferative DR eyes (mild, moderate, and severe), and 8.5% (95% confidence interval: 5.0-14.3) in the proliferative DR eyes. The percentage of nonperfused area increased in a statistically significant manner from eyes without DR, to eyes with nonproliferative DR, to eyes with proliferative DR. Capillary nonperfusion area in the posterior retina increases with increasing DR severity as measured by swept-source OCTA. Quantitative analysis of retinal nonperfusion on wide-field OCTA may be useful for early detection and monitoring of disease in patients with diabetes and DR.