Proton relaxation time of immature brain. II. In vivo measurement of proton relaxation time (T1 and T2) in pediatric brain by MRI.

T1 and T2 of brain tissue were measured in vivo in children by means of an NMR imaging system (resistive magnet 0.15 T). The subjects were 47 children aged from 2 weeks to 15 years. The sites measured were the basal ganglia (thalamus, caudate nucleus and putamen), internal capsule, cerebral cortex and white matter. T1 and T2 in the infant cases were prolonged significantly compared with those in the older children. The prolongation in the white matter was particularly remarkable. In infants approximately 1 year of age, T1 of cerebral cortex already showed no significant changes as compared with T1 in cases aged 15 years. On the other hand, T2 was prolonged significantly up to 3 years of age.