Pilot study utilizing MRI 3D TGSE PASL (arterial spin labeling) differentiating clearance rates of labeled protons in the CNS of patients with early Alzheimer disease from normal subjects.

Objective: To determine the feasibility of 3D TGSE PASL MRI with long inversion times to estimate CNS perfusion clearance, comparing normals to Alzheimer disease patients.

Methods: This pilot study used 3D TGSE PASL MRI with long TIs to estimate the signal clearance of labeled blood/ultra-filtrate (CSF) from brain signal averages of seven inversion times (TI) from six regions of the brain in 18 normal subjects of ages 18-70 years before and after exercise. Arterial pulse corrected signal average per TI versus TI was plotted.