Volumetric quantification of brain volume in children using sequential CT scans.

We devised a three dimensional method for the accurate measurement of brain volume and applied it to 32 neurologically normal children, 7 children with only mental retardation and 15 children with both mental retardation and motor disturbance. In the group of neurologically normal children, the total brain volume increased from 723 cm3 to 1407 cm3 in order of age. The correlation ratio between the total brain volume and age was significant (P less than 0.0001). The values of the total brain volume and the developmental curve were similar to those of the total brain weight of normal children previously reported. The combined volume of the cerebellum, the midbrain, the pons and the medulla also increased from 76 cm3 to 200 cm3 in a manner similar to that of the total brain. The correlation between total brain volume and head circumference was significant (P less than 0.0001). In the group of children with mental retardation, the total brain volume was relatively smaller than that of neurologically normal children. In the group of the children with mental retardation and motor disturbance, 10 out of 15 cases showed values below -2 SD of those of neurologically normal children. The values of the total brain volume were each less than -3 SD in 3 cases whose head circumferences were each more than -3 SD. Our method for the direct measurement of brain volume based on serial CT scans may be useful for the accurate examination of brain development.