Optical Coherence Tomography Angiography Vessel Density in Healthy, Glaucoma Suspect, and Glaucoma Eyes

Purpose: To evaluate and compare optical coherence tomography angiography (OCTA) retinal vasculature measurements in healthy, glaucoma suspect (GS), and glaucoma patients.

Methods: One hundred fourteen eyes with good quality OCTA pictures were included from 38 healthy, 38 GS, 38 and primary open-angle glaucoma (POAG) participants. The information on retinal vasculature was summarized as a vessel density map and as vessel density (%), which is the fraction of the flowing vessel area over the total area examined. The superior, inferior, nasal, and temporal quadrants, as well as whole vessel density (wVD) and peripapillary vessel density (ppVD) data taken from the retinal nerve fiber layer, were studied. Global indices of the visual field were correlated with vessel density measurement.

Results: Mean vessel density was significantly lower in POAG eyes compared with GSs and healthy eyes (wVD) 45.34% ± 6.64%, 50.06% ± 1.97% and 53.06% ± 2.12%, respectively (P < 0.001), and ppVD 47.42% ± 7.73%, 47.42% ± 7.73% and 56.074% ± 2.71%, respectively (P < 0.001). A linear relationship between vessel density (wVD and ppVD) and global indices of the visual field (mean deviation [MD] and pattern standard deviation [PSD]) shows a significant (P < 0.001) relation. R ² is 0.35, 0.36, 0.36, and 0.33 for MD and wVD, PSD and wVD, PSD and ppVD, and MD and ppVD, respectively.

Conclusions: For distinguishing between healthy and glaucoma eyes, OCTA vessel density demonstrated near similar diagnostic accuracy to visual field tests. These findings imply that OCTA measurements reflect damage to tissues important in the pathogenesis of POAG.