Assessment of cerebral blood flow in Alzheimer's disease by spin-labeled magnetic resonance imaging

To evaluate the utility of arterial spin-labeled blood now magnetic resonan ce imaging for the detection of cerebral blood flow abnormalities in Alzhei mer's disease, arterial spin-labeled blood flow images in 16 contiguous 5-m m axial sections were acquired in 18 patients diagnosed with probable Alzhe imer's disease and 11 age-matched controls. Blood flow images from all subj ects were transformed to a standard anatomical space for voxel-by-voxel sta tistical analysis. High quality blood flow images were obtained from all bu t 1 subject Statistical analysis demonstrated significant flow decreases re lative to control subjects in temporal, parietal, frontal, and posterior ci ngulate cortices. Increased severity of disease, as measured by Mini-Mental State Examination, correlated with posterior parietal and posterior cingul ate decreases bur not temporal decreases. Arterial spin-labeled magnetic re sonance imaging was found to be an effective tool for characterizing flow d ecreases accompanying Alzheimer's disease. The absence of ionizing radiatio n or injection and the ability to obtain high quality anatomical images wit hin the same scanning session make arterial spin labeling an attractive tec hnique for the study of Alzheimer's disease, for the evaluation of pharmaco logical therapies, and, possibly, for early diagnosis.