Diabetic retinopathy and OCT angiography: clinical findings and future perspectives

In diabetic retinopathy (DR), macular involvement can present as either macular edema or ischemia. Fluorescein angiography remains the gold standard in the evaluation of retinal vascular perfusion and diagnosis of macular ischemia. However, it is a costly, time-consuming technique, it requires venipuncture, and reports of anaphylaxis and death related to fluorescein injections have been documented, despite their rarity. Optical coherence tomography (OCT) provides a fast and non-invasive method to assess retinal structures at a microscopic level. OCT angiography permits the noninvasive study of retinal and choroid circulation via motion contrast imaging. Split-spectrum amplitude decorrelation angiography combined with OCT angiography has furthered the understanding of retinal and choroidal vascular diseases, allowing the evaluation of retinal microvasculature and identification of subsequent disorders, including DR. Previous studies using OCT angiography have demonstrated that it may demonstrate DR findings such as microaneurysms, arteriolar wall staining, retinal neovascularization, and intraretinal microvascular abnormalities. The purpose of this article is to describe and discuss different concepts regarding OCT angiography, as well as its role in the diagnosis of DR and maculopathy.