Altered perivascular CSF mobility in human cerebral amyloid angiopathy

Motivation: Perivascular spaces (PVS) are mediating brain clearance, i.e. cerebrospinal fluid (CSF) - interstitial fluid exchange, and dilated PVS are a hallmark of cerebral amyloid angiopathy (CAA). However, until now, brain clearance function could not be assessed in humans in vivo. Goal(s): Goal of this study was to assess perivascular cerebrospinal fluid (CSF) mobility in CAA patients. Approach: A CSF mobility-specific 7-Tesla MRI sequence was applied for the first time in patients with CAA and healthy control (HC) subjects. Results: The study revealed perturbed CSF mobility in enlarged perivascular spaces in CAA compared to HC subjects, suggesting impaired perivascular clearance in CAA. Impact: With the finding of a perturbed CSF mobility in enlarged PVS in CAA patients, the study provides proof-of-principal for in vivo measurements of perivascular CSF mobility as a crucial component of the brain clearance pathway in health and disease.