Plexus-Specific Detection of Retinal Vascular Pathologic Conditions with Projection-Resolved OCT Angiography

Purpose: To evaluate the projection-resolved (PR) OCT angiography (OCTA) algorithm in detecting plexus-specific vascular abnormalities in retinal pathologic conditions. Design: Cross-sectional observational clinical study Participants: Patients diagnosed with retinal vascular diseases and healthy volunteers. Methods: Eyes were imaged using an OCT system operating at 840 nm and using the split-spectrum amplitude decorrelation algorithm. A novel algorithm suppressed projection artifacts inherent to OCTA. The volumetric scans were segmented and visualized on different plexuses. Main Outcome Measures: Qualitative observation of vascular abnormalities on both cross-sectional and en face PR-OCTA images. Results: Eight illustrative cases are described. In cases of diabetic retinopathy, retinal vessel occlusion, and retinitis pigmentosa, PR-OCTA detected retinal nonperfusion regions within deeper retinal plexuses not visualized by conventional OCTA. In age-related macular degeneration, cross-sectional PR-OCTA allowed the classification of choroidal neovascularization, and, in a case of retinal angiomatous proliferation, identified a vertical vessel contiguous with the deep capillary plexus. In macular telangiectasia, PR-OCTA detected a diving perifoveal vein and delineated subretinal neovascularization. Conclusions: Application of PR-OCTA promises to improve sensitive, accurate evaluation of individual vascular plexuses in multiple retinal diseases.