Cerebrospinal Fluid Flow within Ventricles and Perivascular Subarachnoid Space Evaluated by Velocity Selective Spin Labeling MRI

Motivation: To map the recently discovered perivascular subarachnoid space (PVSAS) system and investigate cerebrospinal fluid (CSF) dynamics within it. Goal(s): To evaluate CSF flow dynamics within the perivascular space, ventricles, and the novel PVSAS system using velocity selective spin labeling (VSSL) method. Approach: Fourier-transform-based velocity selective inversion was employed to measure CSF flow and calibrated against phase-contrast MRI. Results: The VSSL method successfully measured CSF flow in the PVSAS of major arteries, including middle, anterior, and posterior cerebral arteries, with average flow velocity of 0.34 ± 0.12 cm/s and weak orientation dependency. CSF flow in the ventricles (0.31 ± 0.12 cm/s) was also measured. Impact: This study underscores the potential of VSSL MRI as a non-invasive tool for investigating CSF dynamics in both PVSAS of arteries and ventricles, offering significant insights into CSF circulation in both healthy and pathological conditions.