MR-based Parenchymal CSF water fraction (CSFF) is a marker of glymphatic clearance function and relates to beta-amyloid deposition on 11C-PiB PET

Glymphatic clearance has recently gained increasing attention as a major driver of neurodegenerative diseases like Alzheimer’s disease. Perivascular spaces is believed to reflect glymphatic clearance such that enlargement of the PVS is believed to reflect blocked glymphatic clearance. We present preliminary work on a MR-based FAST-T2 CSF water fraction map to study glymphatic clearance. Our results show a quadratic relationship between CSFF and PiB PET SUVR in AD-specific regions. This indicates that CSFF could be a biomarker of dysfunctional glymphatic clearance, leading to early beta amyloid accumulation, since early on, CSFF increases without a significant change in PiB PET SUVR.