Optical Coherence Tomography Angiography of Diabetic Retinopathy in Human Subjects

TLDR

Optical coherence tomography angiography (OCTA) is a novel, non‑invasive OCT technique capable of imaging the retinal vasculature. This study aims to evaluate the retinal microvasculature in diabetic human subjects with OCTA and assess potential clinical applications. The authors performed a cross‑sectional study of 33 diabetic retinopathy patients, acquiring 3 mm × 3 mm swept‑source OCTA images with a phase‑ and intensity‑based contrasting algorithm and comparing the angiograms to clinical examinations and fluorescein angiography to evaluate accuracy and clinical utility. OCTA revealed the majority of clinically relevant vascular changes in diabetic retinopathy—such as microaneurysms, impaired perfusion, intraretinal fluid, vascular loops, microvascular abnormalities, neovascularization, and cotton‑wool spots—consistently with fluorescein angiography, and demonstrated that OCTA, alone or combined with standard OCT, is at least as effective as fluorescein angiography for assessing macular complications. Published in Ophthalmic Surgery Lasers Imaging Retina, 2015;46:796–805.

Abstract

BACKGROUND AND OBJECTIVE: Optical coherence tomography angiography (OCTA) is a novel, non-invasive OCT technique capable of imaging the retinal vasculature. This study aims to evaluate the retinal microvasculature in diabetic human subjects with OCTA and assess potential clinical applications. PATIENTS AND METHODS: Cross-sectional study of 33 subjects with diabetic retinopathy. OCTA was performed on 3 mm × 3 mm sections using a swept-source OCTA prototype and a phase- and intensity-based contrasting algorithm. OCT angiograms were studied with corresponding clinical examination and fluorescein angiograms, when available, to assess accuracy and clinical utility. RESULTS: OCTA was able to demonstrate most clinically relevant vascular changes in subjects with diabetic retinopathy, including microaneurysms, impaired vascular perfusion, some forms of intraretinal fluid, vascular loops, intraretinal microvascular abnormalities, neovascularization, and cotton-wool spots that were largely consistent with fluorescein angiography. CONCLUSION: OCTA generates high-resolution angiograms that illustrate many of the clinically relevant findings in diabetic retinopathy and offers a novel complement or alternative to fluorescein angiography. Although currently an investigational technique, OCTA in combination with standard OCT imaging is at least as good as fluorescein angiography in the evaluation of the macular complications of diabetic retinopathy. [ Ophthalmic Surg Lasers Imaging Retina. 2015;46:796–805.]