Progressive brain atrophy during normal aging in man: a quantitative computerized tomography study.

We quantitatively evaluated the computerized tomograms (CT) of 148 neurologically intact subjects, aged 28 to 84 years, to examine the effect of normal aging on the integrity of brain mass. Ten parameters were measured in each CT scan as indices for brain volume, including size of lateral, third and fourth ventricles, width of the sylvian and interhemispheric fissures, cortical sulci and the prepontine cistern. Most of these measurements showed that advancing age is associated with progressive loss of brain substance. Data show that the atrophy of brain during normal aging is both cortical and central and is not limited to the older population, but begins at a young age. These normative measurements may serve for comparison with data obtained from CT scans of patients with various neurological disorders.