Repeatability and Reproducibility of 4.5 by 4.5 mm Peripapillary Optical Coherence Tomography Angiography Scans in Glaucoma and Non-Glaucoma Eyes.

PRCIS: Peripapillary vessel parameters from optical coherence tomography angiography (OCTA) 4.5×4.5 mm scans in nonglaucomatous and glaucomatous eyes showed high repeatability and reproducibility, with higher reliability for commercially developed OCTA parameters compared with custom OCTA parameters. PURPOSE: The purpose of this study was to assess intrasession repeatability versus intersession reproducibility of peripapillary vessel parameters from 4.5×4.5 mm OCTA scans in nonglaucomatous eyes and glaucomatous eyes. MATERIALS AND METHODS: In a longitudinal study, peripapillary OCTA scans were quantified using research-oriented custom quantification software that calculated vessel area density (VAD) and flux and clinic-oriented commercially developed software (Cirrus 11.0) that calculated perfusion density (PD) and flux index (FI). Intrasession repeatability and intersession reproducibility were evaluated using within-eye coefficient of variation (CV W ) and intraclass correlation coefficient (ICC). RESULTS: With 127 nonglaucomatous eyes, intrasession CV W for VAD, PD, flux, and FI were 1.900%, 1.174%, 2.787%, and 1.425%, respectively. The intersession CV W were 2.039%, 1.606%, 4.053%, and 2.798%, respectively. Intrasession ICC ranged from 0.903 to 0.956, and intersession ICC ranged from 0.850 to 0.896. Among 144 glaucomatous eyes, intrasession CV W for VAD, PD, flux, and FI were: 3.841%, 1.493%, 5.009%, and 2.432%, respectively. The intersession CV W were 4.991%, 2.155%, 6.360%, and 3.458%, respectively. Intrasession ICC ranged from 0.956 to 0.969, and intersession ICC ranged from 0.918 to 0.964. CONCLUSIONS: Among nonglaucomatous and glaucomatous eyes, the majority of peripapillary OCTA vessel parameters from 4.5×4.5 mm scans had greater intrasession repeatability than intersession reproducibility. There was a greater agreement for the commercially developed quantification parameters than for their custom quantification counterparts.

Hemiretinal Asymmetry in Peripapillary Vessel Density in Healthy, Glaucoma Suspect, and Glaucoma Eyes.

PURPOSE: To investigate hemiretinal asymmetry in radial peripapillary capillary vessel area density (VAD) of healthy, glaucoma suspect, and glaucoma eyes of varying severity and its diagnostic utility for glaucoma. DESIGN: Population-based, cross-sectional study. METHODS: Optic disc scans (6 × 6 mm) were collected on optical coherence tomography angiography (OCTA) to obtain VAD and on optical coherence tomography (OCT) to measure circumpapillary retinal nerve fiber layer (RNFL) thickness. Hemiretinal difference in VAD (hdVAD) was defined as the absolute difference between superior and inferior hemiretinal VAD. Age-adjusted multivariable linear regression of hdVAD on glaucoma severity was performed. Areas under curves (AUCs) were calculated from predicted probabilities generated by multiple logistic regression of glaucoma severity on age-adjusted single and combined parameters. RESULTS: A total of 1,043 eyes of 1,043 participants (587 healthy, 270 suspect, 67 mild, 54 moderate, 65 severe glaucoma) were included. After age adjustment, mean hdVAD was similar between healthy and suspect (P = .225), higher in mild vs suspect (P < .001), and higher in moderate vs mild (P = .018), but lower in severe vs moderate (P = .001). AUCs of hdVAD were highest for discriminating mild (0.685) and moderate (0.681) glaucoma from healthy. Combining hdVAD and global RNFL (gRNFL) yielded the highest AUCs of all parameters for mild (0.818) and any POAG (0.859) and resulted in significantly better diagnostic accuracy than either hdVAD or gRNFL alone (P < .05 for all comparisons). CONCLUSIONS: hdVAD is higher in early glaucoma and may help with early detection when damage is focal, but its diagnostic ability appears less robust in advanced glaucoma when damage is diffuse.