Brain maturation followed by computed tomography.

Computed tomography scans of normal infants were analyzed by computer methods to determine the average brain tissue density during development. A 20% increase was found from term to 20 weeks of age (29 to 35 Hounsfield units); then no further significant change was found over the next 60 weeks. The increase in density parallels the known increase in dry weight of the tissue, but calculations indicate that biochemical changes, such as the accumulation of lipids, are also important.