Cerebral blood flow, arterial pulsation, and vasomotion may be important indicators of cerebrovascular health in aging and diseases of aging such as Alzheimer's disease. Noninvasive markers that assess these characteristics may be helpful in the study of co-occurrence of these diseases and potential additive and interacting effects. In this study, 4D flow MRI was used to measure intra-cranial flow features with cardiac-gated phase contrast MRI in cranial arteries and veins. Mean blood flow and pulsatility index as well as the transit time of the peak flow from the middle cerebral artery to the superior sagittal sinus were measured in a total of 104 subjects comprising of four groups: (a) subjects with Alzheimer's disease, (b) age-matched controls, (c) subjects with mild cognitive impairment, and (d) a group of late middle-aged with parental history of sporadic Alzheimer's disease. The Alzheimer's disease group exhibited: a significant decrease in mean blood flow in the superior sagittal sinus, transverse sinus, middle cerebral artery, and internal carotid arteries; a significant decrease of the peak and end diastolic blood flow in the middle cerebral artery and superior sagittal sinus; a faster transmission of peak flow from the middle cerebral artery to the superior sagittal sinus and increased pulsatility index along the carotid siphon.
Keywords: 4D flow MRI; Alzheimer’s disease; mean blood flow; mild cognitive impairment; pulsatility index.