Quantifying Choriocapillaris Flow Voids in Patients With Geographic Atrophy Using Swept-Source OCT Angiography

BACKGROUND AND OBJECTIVE: To compare choriocapillaris (CC) flow voids (FVs) throughout the macula in patients with age-related macular degeneration (AMD) and geographic atrophy (GA) to age-similar controls using swept-source optical coherence tomography angiography (SS-OCTA). PATIENTS AND METHODS: In this cross-sectional study, 12 subjects with GA secondary to nonexudative AMD and 12 age-similar controls participated. SS-OCTA was performed using a 6 mm × 6 mm scanning pattern. CC FVs were calculated using a one-standard deviation thresholding method developed from a normal database. RESULTS: CC FVs were significantly increased in patients with GA compared with age-similar controls (P < .001). FVs within 2° of GA were significantly increased compared with the area outside 2° (P < .001). FVs beyond 2° of GA were significantly increased compared with age-similar controls (P < .001). CONCLUSIONS: FV analysis of in vivo CC images revealed diffuse CC perfusion deficits throughout the macular region in subjects with GA secondary to nonexudative AMD. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:e229-e235.].