Cerebral blood flow in Alzheimer's disease by Arterial Spin Labeling QUASAR

Background: Arterial Spin Labeling (ASL) is quantitative and effective in detection of cerebral blood flow abnormalities in Alzheimer’s disease (AD) [1]. Here, we attempt to employ the QUASAR ASL pulse sequence [2,3] to compare whole brain cerebral blood flow (CBF) in AD and cognitively normal elderly subjects in a Chinese population. Currently, there is no definite diagnostic biomarker for the assessment of AD. Earliest 18-fluoro-deoxyglucose positron emission tomography (18F-FDGPET) found hypometabolism affecting the temporal and parietal association areas [4]. As glucose metabolism is thought to be directly related to cerebral blood flow [5], we employ ASL as an indirect marker of glucose metabolism in patients with AD and compare them to normal elderly subjects. The utility of ASL in distinguishing various stages of AD from amnesic mild cognitive impairment (MCI) preceding dementia to fully developed dementia for prognostication, selection and monitoring of treatment is also of clinical importance.