4D CSF flowmetry to map brain-wide slow CSF flow dynamics and patterns in subarachnoid space

Cerebrospinal fluid (CSF) flow is a key component of the brain’s waste clearance system. However, little is known about the brain-wide CSF flow in subarachnoid space (SAS), due to the low sensitivity of MRI-based flow imaging methods for measuring slow flow. Here, we proposed a phase-contrast 4D CSF flowmetry method using a pulsed-gradient-spin-echo EPI sequence, providing high sensitivity and efficiency to measure brain-wide slow CSF flow dynamics in SAS. Whole-brain CSF flow dynamics including velocity and direction changes were measured and our preliminary data suggest that both cardiac pulsation and respiration can drive CSF flow in both ventricles and SAS.