Cerebral perfusion measurements in elderly with hypertension using arterial spin labeling

Purpose: The current study assesses the feasibility and value of crushed cerebral blood flow (CBF_crushed) and arterial transit time (ATT) estimations for large clinical imaging studies in elderly with hypertension. Material and Methods: Two pseudo-continuous arterial spin labeling (ASL) scans with (CBF_crushed) and without flow crushers (CBF_non-crushed) were performed in 186 elderly with hypertension, from which CBF and ATT maps were calculated. Standard flow territory maps were subdivided into proximal, intermediate and distal flow territories, based on the measured ATT. The coefficient of variation (CV) and physiological correlations with age and gender were compared between the three perfusion parameters. Results: There was no difference in CV between CBF_crushed and CBF_non-crushed (15-24%, p>0.4) but the CV of ATT (4-9%) was much smaller. The total gray matter correlations with age and gender weremost significant with ATT (p = .016 and p<.001 respectively), in between for CBF_crushed (p = .206 and p = .019) and least significant for CBF_non-crushed (p = .236 and p = .100). Conclusion: These data show the feasibility and added value of combined measurements of both crushed CBF and ATT for group analyses in elderly with hypertension. The obtained flow territories provide knowledge on vascular anatomy of elderly with hypertension and can be used in future studies to investigate regional vascular effects.