Evaluation of the effect of the severity of diabetic retinopathy on microvascular abnormalities and vascular density using optical coherence tomography angiography.

Purpose: To quantify and to study the relationship between retinal microvascular changes and different stages of diabetic retinopathy (DR) using optical coherence tomography angiography (OCTA).

Methods: This prospective observational study included the eyes of patients with different stages of DR. OCTA was performed in all eyes using a 9 × 9 mm protocol.