Retinal Microvasculature in Nonproliferative Diabetic Retinopathy: Automated Quantitative Optical Coherence Tomography Angiography Assessment

Abstract

Purpose: To perform a qualitative and quantitative assessment of the foveal microvasculature in eyes with diabetic maculopathy using optical coherence tomography angiography (OCT-A). Methods: Retrospective case series of 48 eyes with diabetic maculopathy and 47 healthy eyes evaluated by Spectralis OCT-A. Perifoveal arcade disruptions, linear vascular dilations, microaneurysms, intraretinal microvascular abnormalities and flow-void areas were qualitatively analyzed on OCT angiograms both for the superficial (SCP) and deep (DCP) capillary plexuses. A fully automated microstructural analysis of the foveal avascular zone (FAZ) metrics, vascular and avascular surfaces was performed. Quantitative values from diabetic patients were compared with those of healthy subjects. Results: A moderate agreement between SCP and DCP in terms of diabetes-induced vascular lesions in the qualitative assessment was shown. The comparative quantitative analysis between SCP and DCP in diabetic patients revealed a statistically significant difference (p < 0.05) in terms of FAZ perimeter and FAZ surface. No statistically significant difference was shown in total vascular and avascular surfaces. A statistically significant difference between the diabetic and control groups was noticed both for SCP and DCP considering FAZ metrics and vascular surfaces. Conclusions: A qualitative and quantitative OCT-A approach on retinal vascular perfusion may offer an objective and reliable method for monitoring disease progression in diabetic retinopathy.