Associations between retinal microvasculature, ocular blood flow, and cerebral blood flow in healthy adults

Motivation: Is retinal microvasculature a "window" to brain physiology? Goal(s): Test correlations between ocular blood flow, cerebral blood flow, and retinal microvasculature. Approach: We measured ocular blood flow (OBF) and cerebral blood flow (CBF) using arterial spin labeling (ASL) and retinal vessel density (VD) using optical ocular coherence tomographic angiography (OCTA) in healthy adults aged 21-85 years. Results: OBF showed comparable repeatability as ASL gray matter (GM) CBF. Additionally, OBF positively correlated with OCTA VD and both correlated with GM CBF in the anterior circulation. Impact: Observed structural and functional associations in retinal vasculature support the notion of the eye as a window to brain perfusion.