Quantifying brain-wide cerebrospinal fluid flow dynamics using slow-flow-sensitized phase-contrast MRI

Dong, Z.; Wang, F.; Strom, A.; Eckstein, K.; Bachrata, B.; Robinson, S. D.; Rosen, B. R.; Wald, L. L.; Lewis, L. D.; Polimeni, J. R.

doi:10.1101/2025.03.22.644745

bioRxiv · 10.1101/2025.03.22.644745

Quantifying brain-wide cerebrospinal fluid flow dynamics using slow-flow-sensitized phase-contrast MRI

Dong, Z.·Wang, F.·Strom, A.·Eckstein, K.·Bachrata, B.·Robinson, S. D.·Rosen, B. R.·Wald, L. L.·Lewis, L. D.·Polimeni, J. R.

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Abstract

Cerebrospinal fluid (CSF) flow is a key component of the brains waste clearance system. However, our understanding of CSF flow in the human brain, particularly within the brain-wide subarachnoid space (SAS), is limited due to a lack of non-invasive tools for measuring slow flow. Here, we propose a CSF flowmetry technique using phase-contrast MRI combined with a slow-flow-sensitized acquisition. It achieves high sensitivity in measuring slow CSF flow (e.g., 100 m/s), and enables quantitative measurement of the velocity and direction with whole-brain coverage, spanning from ventricles to SAS. Our proof-of-concept results demonstrate repeatable flow measurements and show that cardiac pulsation induces coherent CSF flow changes within the SAS. Our data also suggest that cardiac pulsation has a stronger driving effect on brain-wide CSF flow compared to respiration. This technique provides a valuable tool for investigating CSF dynamics and pathways to advance a holistic understanding of brain-wide CSF flow. TeaserA novel MR technique enables noninvasive, quantitative mapping of slow cerebrospinal fluid flow in the subarachnoid space across the human brain.

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Dong, Z., Wang, F., Strom, A., Eckstein, K., Bachrata, B., Robinson, S. D., Rosen, B. R., Wald, L. L., Lewis, L. D., Polimeni, J. R.. 2025-03-25. Quantifying brain-wide cerebrospinal fluid flow dynamics using slow-flow-sensitized phase-contrast MRI. https://doi.org/10.1101/2025.03.22.644745

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