Effects of Age on Peripapillary and Macular Vessel Density Determined Using Optical Coherence Tomography Angiography in Healthy Eyes

Abstract

Purpose: To evaluate the effect of age on global and sectoral vascular parameters of the peripapillary area and macula in healthy eyes by using optical coherence tomography angiography (OCT-A). Methods: This retrospective cross-sectional study included 239 eyes of 172 healthy subjects. Subjects were scanned using the high-definition disc angio scan (4.5 × 4.5 mm), retina angio scan (6 × 6 mm), and optic nerve head/ganglion cell complex (GCC) modes of OCT-A. Global and sectoral circumpapillary vessel density (VD), parafoveal VD, retinal nerve fiber layer (RNFL), and GCC thickness parameters were modeled in terms of age by using linear mixed-effect models incorporating covariates. Normalized slopes were calculated by dividing the absolute slopes by the mean value of the OCT-A parameters. Results: All global and sectoral circumpapillary VDs decreased significantly with increasing age, except for those in the temporal superior sector. The steepest slopes in the circumpapillary region were observed in nasal superior (-0.098%/y) and nasal inferior (-0.096%/y) sectors. The global, temporal, and superior macular VDs also decreased with increasing age, while the foveal, nasal, and inferior parameters did not. The temporal quadrant showed the steepest slope among the macular parameters (-0.068%/y). The RNFL and GCC thickness results showed similar trends. Conclusions: Age substantially affected VD in most of the peripapillary and macular areas; however, the papillomacular bundle area did not show significant age-related vascular changes. These age-related global and sectoral differences in circumpapillary and macular VDs should be considered when assessing pathologic VD changes over time.