Colin S Tan1, Louis W Lim2, Vernon S Chow2, Isaac W Chay2, Shoun Tan2, Kai Xiong Cheong2, Gabriel T Tan2, SriniVas R Sadda3. 1. National Healthcare Group Eye Institute Tan Tock Seng Hospital, Singapore 2Fundus Image Reading Center, National Healthcare Group Eye Institute, Singapore. 2. National Healthcare Group Eye Institute Tan Tock Seng Hospital, Singapore. 3. Doheny Eye Institute, University of California Los Angeles, Los Angeles, United States.
Abstract
PURPOSE: To determine the size and characteristics of the superficial and deep foveal avascular zone (FAZ) in healthy adults by using optical coherence tomography angiography (OCT-A), and to ascertain the effects of demographic and ocular parameters on the FAZ size. METHODS: In a prospective cohort study of 117 healthy volunteers, foveal-centered 3 × 3-mm OCT-A scans were manually graded by certified graders to determine the size of the superficial and deep FAZ. Multiple linear regression analyses were performed to evaluate the impact of demographics and ocular factors, including central retinal thickness (CRT), choroidal thickness, axial length (AL), and spherical equivalent (SE) on superficial and deep FAZ areas. RESULTS: The mean age of the participants was 22.5 years, with mean AL of 25.4 mm and mean SE of -4.3 diopters. The mean CRT was 262.8 μm (range, 220-316 μm). The mean superficial FAZ area was 0.24 mm2, while the deep FAZ area was 0.38 mm2 (P < 0.001). Females had a larger superficial (P < 0.001) and deep FAZ (P < 0.001). On univariate linear regression, both superficial and deep FAZ areas had significant correlations with CRT, sex, AL, and SE, but not with age. By multiple linear regression analysis, in normal eyes, superficial FAZ area varied significantly with CRT and sex. Among eyes with high myopia, both superficial and deep FAZ varied significantly with CRT, sex, and choroidal thickness. CONCLUSIONS: The superficial and deep FAZ areas varied significantly among healthy eyes. Factors such as CRT, sex, SE, AL, and choroidal thickness influence the size of the FAZ.
PURPOSE: To determine the size and characteristics of the superficial and deep foveal avascular zone (FAZ) in healthy adults by using optical coherence tomography angiography (OCT-A), and to ascertain the effects of demographic and ocular parameters on the FAZ size. METHODS: In a prospective cohort study of 117 healthy volunteers, foveal-centered 3 × 3-mm OCT-A scans were manually graded by certified graders to determine the size of the superficial and deep FAZ. Multiple linear regression analyses were performed to evaluate the impact of demographics and ocular factors, including central retinal thickness (CRT), choroidal thickness, axial length (AL), and spherical equivalent (SE) on superficial and deep FAZ areas. RESULTS: The mean age of the participants was 22.5 years, with mean AL of 25.4 mm and mean SE of -4.3 diopters. The mean CRT was 262.8 μm (range, 220-316 μm). The mean superficial FAZ area was 0.24 mm2, while the deep FAZ area was 0.38 mm2 (P < 0.001). Females had a larger superficial (P < 0.001) and deep FAZ (P < 0.001). On univariate linear regression, both superficial and deep FAZ areas had significant correlations with CRT, sex, AL, and SE, but not with age. By multiple linear regression analysis, in normal eyes, superficial FAZ area varied significantly with CRT and sex. Among eyes with high myopia, both superficial and deep FAZ varied significantly with CRT, sex, and choroidal thickness. CONCLUSIONS: The superficial and deep FAZ areas varied significantly among healthy eyes. Factors such as CRT, sex, SE, AL, and choroidal thickness influence the size of the FAZ.
Authors: Amir H Kashani; Chieh-Li Chen; Jin K Gahm; Fang Zheng; Grace M Richter; Philip J Rosenfeld; Yonggang Shi; Ruikang K Wang Journal: Prog Retin Eye Res Date: 2017-07-29 Impact factor: 21.198
Authors: Rachel Linderman; Alexander E Salmon; Margaret Strampe; Madia Russillo; Jamil Khan; Joseph Carroll Journal: Transl Vis Sci Technol Date: 2017-06-09 Impact factor: 3.283