COMPUTED-TOMOGRAPHY IN ALZHEIMERS-DISEASE - A LONGITUDINAL-STUDY

Sixty-three patients satisfying NINCDS/ADRDA criteria for Alzheimer's disease (AD) received neuropsychological tests and computed tomography (CT) scans 12 months apart. Significant deterioration occurred in all the cognitive tests and in the CT measures used, that is, lateral ventricular size, third ventricular size, and cortical atrophy. There was a wide variation in the size of the changes taking place; 14 of 63 patients showed no significant change and 6 showed a marked increase in ventricular size. However, neither group differed from the others in any demographic, cognitive, or other CT variables which suggested, on the CT measures used, that no clearly identifiable subgroups of AD were present. Change in CT indices was not related to initial severity of disease. An increase in ventricular size was related to deterioration of cognitive function. These results require further replication. The methodological drawbacks of such studies are discussed.