Cerebrospinal fluid-based spatial statistics: towards quantitative analysis of cerebrospinal fluid pseudodiffusivity

Motivation: Cerebrospinal fluid (CSF) circulation is crucial for removing waste from the brain, and abnormal CSF motion was associated with neurodegenerative diseases. This study aims to use low b-value diffusion MRI to assess the variance of motion of CSF, i.e., pseudodiffusivity, and investigate its association with cognitive impairment. Goal(s): To quantify CSF pseudodiffusivity within each sulcus, cistern and ventricle. Approach: In 93 participants from a memory clinic, Intravoxel incoherent motion (IVIM) MRI was performed to measure CSF pseudodiffusivity. Sulci and cisterns were segmented based on gray matter landmarks. Results: In the third ventricle, CSF pseudodiffusivity was positively correlated with memory performance. Impact: Our method of quantifying CSF pseudodiffusivity in different CSF regions in an unbiased, automatic fashion enabled discovery of potential novel non-invasive CSF-based imaging biomarkers of cognitive impairment.