Detection of amyloid-related imaging abnormality (ARIA) in Alzheimer’s patients receiving anti-amyloid antibody therapy using long-TE ASL MRI

Motivation: Anti-amyloid antibody therapy has brought excitement to the Alzheimer's community but the common side-effect of amyloid-related imaging abnormality (ARIA) related to small vessel damage still represents a major caveat. Goal(s): To conduct early detection of ARIA using long-TE arterial-spin labeling (ASL) MRI. Approach: Three Alzheimer's patients were studied. ASL CSF fraction maps were obtained using a long-TE ASL with effective TE (eTE)=480ms. Three healthy volunteers were also studied. Results: Regions with brain lesions or ARIA-E revealed higher ASL CSF fraction when compared to the rest of the brain. ASL CSF fraction in deep-brain was higher in patients than in controls. Impact: This study demonstrated the first application of long-TE ASL in AD patients receiving anti-amyloid antibody therapy. The results support the hypothesis that arterial vessels are leaky following anti-amyloid therapy, presumably due to clearance of amyloid beta (Aβ) from vessel walls.