Role of OCT Angiography OCTA in the Diagnosis of Macular Diseases

Abstract

OCT becomes an indispensable tool in everyday practice. OCTA is the functional extension that provides cross-sectional information on retinal and choroidal circulations without dye injection. It allows visualization of abnormal flow in areas with no flow and abnormal vessels (like CNVM). In ARMD, it can detect active membranes before being leaky in FFA. In diabetic retinopathy, OCTA can diagnose abnormal areas of non-perfusion in the superficial plexus, deeper capillary structures, or neovascularization. OCTA can detect focal dilation and foveal capillaries alterations in macular telangiectasia. It is useful in the diagnosis of inherited retinal diseases such as retinitis pigmentosa. OCTA has many challenges including longer acquisition times and motion artifacts. Longer wavelength SS-OCT may provide a solution for imaging through media opacities and a wider field of view. OCTA does not give full details about the retinal periphery, also, it gives no information about blood-retinal barrier (no dye to leak); an important sign in many retinal diseases.