Wide-Field and Projection-Resolved Optical Coherence Tomography Angiography in Diabetic Retinopathy

Diabetic retinopathy (DR) is a leading cause of vision loss in working-age Americans. Capillary damage from hyperglycemia causes vision loss through downstream effects, such as retinal ischemia, edema, and neovascularization (NV). Proper screening and timely treatment with laser photocoagulation and anti-vascular endothelial growth factor (VEGF) injections can minimize morbidity. In the last decade, clinicians have been able to use objective structural data from optical coherence tomography (OCT) to guide the treatment of diabetic macular edema. Other aspects of care, however, still largely depend on subjective interpretation of clinical features and fluorescein angiography (FA) to determine the disease severity and treatment threshold. The recently developed OCT angiography (OCTA) provides dye-less, injection-free, three-dimensional images of the retinal and choroidal circulation with high capillary contrast. Not only is it safer, faster, and less expensive than conventional dye-based angiography, OCTA provides the potential of giving clinicians objective tools for determining severity of disease by detecting and quantifying NV and non-perfusion.