Perfusion Velocity in Temporal Lobe Decreases Prior to Its Change in Other Brain Regions in Alzheimer’s Disease

Motivation: Reduced cerebral perfusion has been demonstrated in patients with Alzheimer's Disease(AD), but the longitudinal change in cerebral perfusion alteration during disease progression is not well investigated. Goal(s): We investigated regional perfusion velocity change during AD progression, providing a comprehensive view of the temporal alteration of blood supply and perfusion pattern. Approach: Quantitative transport mapping(QTM) is applied to quantify blood perfusion velocity from multi-delay ASL data. Granger causality analysis(GCA) was applied to identify the driving regions of QTM velocity change. Results: We found that the temporal lobe was the driving region and could predict the subsequent QTM velocity changes in other brain regions. Impact: These findings suggest that the perfusion velocity in temporal lobe supplied by MCA has the earliest change among the whole brain regions, which may be an early biomarker for AD diagnosis and offer a therapeutical target.