Analysis of regional cerebral blood flow and metabolism in senile dementia using oxygen-15 and positron emission tomography

Regional cerebral blood flow (rCBF), regional cerebral metabolic rate of oxygen (rCMRO2), regional oxygen extraction fraction (rOEF), and regional cerebral blood volume (rCBV) were compared in five persons with senile dementia with a mean age of 67 +- 11 yr (Group A) and 7 volunteers with a mean age of 57 +- 5 yr (Group B) using positron computed tomography with continuous inhalation of 15O-labeled gases. rCBF and rCMRO2 were significantly smaller in the grey mater in Group A than in Group B; however, this was not significant in the white matter. rOEF was significantly higher in both grey and white matter in Group A than in Group B. There was no significant difference in rCBV between the groups. According to the cerebral sites, rOEF significantly differed in the cerebral cortex, cerebellar hemisphere, and centrum semiovale between the groups, but did not significantly differ in the brain stem, vermis, hippocampus, basal ganglia, left thalamus, and medial upper part of the frontal lobe. Regarding rCBV, there was no regional difference between the groups. (Namekawa, K.)