Abnormal Cerebral Ventricular Change in Alzheimer's Disease Recorded with Cardiac Gated MRI: A Preliminary Report

Abstract

We compare high-resolution cardiac gated brain magnetic resonance imaging of 19 young healthy subjects with a small group of demented subjects - mainly probable senile dementia of the Alzheimer type (SDAT) - with varying degrees of ventricular enlargement. Computer-measured ventricular volume demonstrated cyclic ventricular size variations in all subjects. During cardiac systole, the lateral ventricles vary in size, an average of 10% in the young cohort (0.109 ± 0.061); the lateral ventricles enlarge, often after an initial decrease in size. A later volume expansion may occur, but the amount varies between subjects. One healthy 60-year-old subject, whose ventricles were slightly larger than those of the younger individuals, and all of the demented subjects, had less enlargement when compared to the average young subject. Two demented subjects with ventriculomegaly had small fluctuations: one had only 6.9% variation, the other subject with larger ventricles had no enlargement. One individual with SDAT had more than a 24% volume change while another subject''s increase was delayed. Our results suggest a complex interplay between blood flow, brain compliance and CSF outflow resistance. This small study further suggests that the choroid plexus plays an important role in systole-related lateral ventricular changes, that changes in choroid plexus function may occur in hydrocephalus and that CSF dynamics may be impaired in SDAT disease.