Developmental changes of cerebral blood flow and oxygen metabolism in children

BACKGROUND AND PURPOSE: Normal values for cerebral blood flow (CBF) and metab-olism in adults are well established, but not for children. Our goal, therefore, was to clarify functional developmental changes of the brain in children in relation to CBF and oxygen metabolism. METHODS: We measured regional CBF (rCBF), regional cerebral metabolic rate for oxygen (rCMRO2), and regional oxygen extraction fraction (rOEF), using positron emission tomog-raphy (PET). We performed 30 PET studies in 24 children ages 10 days to 16 years (nine boys, 15 girls), using a steady inhalation method with C15O2, 15O2, and 15CO in order to measure rCBF, rCMRO2, and rOEF, respectively. Regions of interest were set in the primary cerebral areas (sensorimotor, visual, temporal, and parietal cortex), cerebral association areas (frontal and visual association), basal ganglia (lenticular and thalamus), and posterior fossa (brain stem and cerebellar cortex). Subjects were grouped by age (,1, 1 to,3, 3 to,8, and $8 years), and the absolute values of the parameters were compared with those obtained from 10 healthy adults. RESULTS: rCBF and rCMRO2 were lower in the neonatal period than in older childre