Quantitative assessment of flow between cerebrospinal and interstitial fluid compartments in humans

Proceedings of the National Academy of Sciences, Volume 123, Issue 18, May 2026. <br/>SignificanceCerebrospinal fluid-interstitial fluid (CSF–ISF) exchange is central to brain clearance, yet quantitative measurements in humans have been lacking. We establish an MRI approach that enables quantification of CSF–ISF exchange using intrathecal …