Impaired glymphatic system function in individuals with Alzheimer's disease demonstrated by DTI-ALPS index

Motivation: Alzheimer's disease (AD) is a progressive neurodegenerative disorder that primarily affects the brain and leads to diffusion impairment. Goal(s): To evaluate the alterations of glymphatic function in AD and explore its association with cognition and blood biomarkers. Approach: We investigate the functionality of glymphatic system (GS) in patients with AD using diffusion tensor imaging analysis along with the perivascular space (DTI-ALPS). Results: Individuals with AD had a significantly lower ALPS index compared to the healthy controls. Moreover, the decreased ALPS index was associated with impaired cognitive function, as reflected through the Mini-Mental State Examination (MMSE) score and higher blood biomarker ptau-181 levels. Impact: The results demonstrate that the feasibility of DTI-ALPS, which can be used for research on glymphatic system function in AD patients. ALPS-index is expected to become a promising imaging marker and may provide novel targets for clinical diagnosis of AD.