INI Seminar

02.07.2026

Impact of acute sleep deprivation on cerebrospinal fluid dynamics in enlarged perivascular spaces.

Speaker:
Dr. Shoaib A. Goraya (Brigham and Women’s Hospital, Harvard Medical School, Boston)

Venue:
NB 3/57 and Zoom: https://ruhr-uni-bochum.zoom-x.de/j/62036362682?pwd=5otaPEhG3pm2G4XYSkpGuT2JTLWvA3.1 

Starting time:
3:00 pm

Abstract:
The glymphatic system is a mechanism primarily responsible for clearing brain's neurotoxins through cerebrospinal fluid (CSF) flow along thin channels that surround the brain's blood vessels, known as perivascular spaces. This clearance is thought to be most active during sleep, and sleep deprivation is believed to impair it. The standard MRI correlate is perivascular space (PVS) enlargement, a static structural marker that reflects morphological dilation but not the underlying CSF dynamics or their drivers. We developed a patient-specific digital twin that simulates the fluid mechanics in the PVS. The model captures the two-way coupling between pulsatile blood flow and the arterial wall that moves the CSF in the surrounding PVS. Thirty healthy adults (ages 20 to 38) underwent 7T MRI at three time points: baseline, after 24 hours of acute sleep deprivation (SD), and after 72 hours of recovery. For each scan, AI segmentation reconstructed the subject-specific geometry of the perivascular spaces, which then served as the modeling domain. We summarized transport with two metrics: a net forward flow index (NFFI), how much CSF is pushed through on balance, and a pulsatility index (PI), how strongly the flow oscillates with each heartbeat. Our results indicate that the structure and function changed together, and both recovered. After one night of sleep deprivation, perivascular space volume increased by 11.38% from baseline (p < 0.0001), then showed no significant difference from baseline after recovery, confirming the enlargement is transient. The simulations revealed a matching functional decline: net forward flow dropped by 13.56% and pulsatility rose by 8.03% after sleep deprivation (both p < 0.001), and both normalized once volume was restored. In short, a single night of lost sleep sets off a linked, fully reversible chain of structural and functional change in the brain's fluid system. The result also makes a methodological point: simulation-derived flow metrics can act as functional biomarkers of glymphatic health, capturing the transport mechanics that structural imaging alone cannot reveal.