Imaging choroidal neovascular membrane using en face swept-source optical coherence tomography angiography

PURPOSE The aim of this study was to assess the efficacy of swept-source optical coherence tomography angiography (SS-OCTA) in delineating the morphology of choroidal neovascular membrane (CNV). PATIENTS AND METHODS This was a retrospective observational case series reviewing clinical data and fundus fluorescein angiography (FFA), swept-source optical coherence tomography (SS-OCT), and SS-OCTA images of patients with CNV and comparing the findings. The swept-source technology enables deeper penetration and superior axial resolution. The incorporated blood flow detection algorithm, optical coherence tomography angiography ratio analysis (OCTARA), enables visualization of CNV in vivo without the need for dye injection. RESULTS The study included 136 eyes of 105 patients. Active lesions on SS-OCTA images showed increased capillary density, extensive arborization, vascular anastomosis and looping, and peri-lesional hollow. Inactive lesions showed decreased capillary density, presence of large linear vessels, and presence of feeder vessels supplying the CNV. We detected positive correlation between SS-OCTA, FFA, and SS-OCT images in 97% of eyes. In the remaining 3%, SS-OCTA confirmed the absence of CNV, whereas FFA and SS-OCT either were inconclusive in the diagnosis of CNV or yielded false-positive results. CONCLUSION SS-OCT and SS-OCTA represent a reproducible risk-free analog for FFA in imaging CNV. SS-OCTA is particularly versatile in cases where FFA and SS-OCT are inconclusive.