Abstract
Optical coherence tomography angiography (OCT-A) is an emerging technology that captures flow motion within the retinal vasculature to produce angiograms. Compared to dye-based angiography techniques, OCTA is a noninvasive and fast method that enables detailed visualization of the vasculature, which is not easily observable using previously available techniques. Over the past decade, OCT-A has been used to characterize the pathological features of choroidal neovascularization (CNV) associated with several retinal diseases, including neovascular age-related macular degeneration (AMD). In eyes at risk of developing CNV, OCT-A has demonstrated the capability to detect subclinical signs of neovascularization (NV) that may enable early treatment and better visual outcomes. Various CNV conditions are now routinely treated with intravitreal injections of anti-vascular endothelial growth factor (anti-VEGF). OCT-A was used to identify the characteristics of CNV at various stages, before and after anti-VEGF therapy. Although preliminary, OCT-A has demonstrated the potential to help guide treatment decisions in CNV cases that respond differently to anti-VEGF therapy.
Despite its multiple advantages and applications, the clinical use of OCT-A remains limited. OCT-A has several limitations, including visualization of a small area, the presence of artifacts, and results that are challenging to interpret. However, OCTA technology continues to advance as some of the early limitations have been resolved. Overall, OCT-A promises to be a significant step forward in our current ability to visualize pathological CNV, and has the potential to improve both the diagnosis and management of a variety of retinal diseases.
Keywords: Age-related macular degeneration, Anti–vascular endothelial growth factor, Myopic choroidal neovascularization, Central serous chorioretinopathy, Choroidal neovascularization, Geographic atrophy, Ischemic macula, Optical coherence tomography angiography, Pathological choroidal neovascularization, Type I and Type II choroidal neovascularization, Vascular endothelial growth factor.