VOLUMETRIC MAGNETIC-RESONANCE-IMAGING IN MEN WITH DEMENTIA OF THE ALZHEIMER-TYPE - CORRELATIONS WITH DISEASE SEVERITY

Using magnetic resonance imaging (MRI), we measured the volumes of var ious brain structures and cerebrospinal fluid (CSF) in 19 men with dem entia of the Alzheimer type (DAT) and 18 healthy age-matched control m en. The mean (+/- S.D) Mini-Mental State exam score (MMSE) of the DAT men was 16 +/- 7; 9 were mildly (MMSE > 20), 5 moderately (MMSE 10-20) , and 5 severely (MMSE < 10) demented. Brain and CSF volumes were norm alized as a percent of the traced intracranial volume to control for t he relation of volumes of cerebral structures to head size, and analyz ed statistically. The whole group of DAT subjects had significantly sm aller mean cerebral brain matter and temporal lobe volumes (p < 0.05), and significantly, larger mean ventricular and temporal lobe peripher al CSF volumes than did controls. Mean volumes of the subcortical nucl ei did not differ significantly between groups, and mean volume of tem poral lobe brain matter decreased significantly more than whole brain, suggesting regional loss of brain matter in DAT. Mildly demented DAT patients had significantly smaller mean cerebral brain matter and temp oral lobe volumes and significantly larger volumes of lateral ventricl es, and of temporal lobe peripheral CSF, than did controls. Neuropsych ological measures of disease severity in DAT patients were significant ly (p < 0.05) and appropriately correlated to volumes of cerebral brai n matter and right lateral ventricle. These results suggest that in DA T: (i) significant brain atrophy is present early in the disease proce ss, (ii) brain atrophy correlates with severity of cognitive impairmen t, and (iii) there is greater involvement of the telencephalic associa tion system than whole brain, and there is relative sparing of the cau date, lenticular and thalamic nuclei.