Computerised tomography and intellectual impairment in the elderly.

Sixty-six elderly subjects (mean age 77 years) whose mental state was assessed clinically and by simple psychometric tests have been studied by computerised tomography. The mean maximum ventricular area in the 17 mentally normal subjects was above the upper limit of normal for younger subjects, and there was a broad relationship between increasing ventricular dilatation and increasing intellectual impairment. No such clear relationship was demonstrable for measures of cortical atrophy.