VOLUMES OF HIPPOCAMPUS, AMYGDALA AND FRONTAL LOBES IN THE MRI-BASED DIAGNOSIS OF EARLY ALZHEIMERS-DISEASE - CORRELATION WITH MEMORY FUNCTIONS

We studied the usefulness of measuring volumes of the hippocampus, amy gdala and frontal lobes with coronal magnetic resonance imaging (MRI) scans in the diagnosis of early Alzheimer's disease (AD). We examined 32 patients diagnosed according to the NINCDS-ADRDA criteria of probab le AD and 16 age-matched healthy cognitively normal controls. The AD p atients had mild dementia with a mean score of 22.8 in the Mini-Mental Status Examination (MMSE). We used a 1.5 T magnetic resonance imager and normalized the volumes for brain area. The AD patients had signifi cantly smaller volumes of the right and the left hippocampus (-38%) (A NOVA, p < 0.0001) and the left frontal lobe (-16%, p < 0.05) compared to controls. The reductions in volumes of the right frontal lobe (-13% ), the right amygdala (-14%) or the left amygdala (-18%) were not stat istically significant. In the discriminant function analysis which inc luded the volumes of the hippocampus, amygdala, and the frontal lobes and age, the volumes of the left and right hippocampus, the left and r ight frontal lobe, and the right amygdala entered the model and we cou ld correctly classify 92% of the subjects into AD and control groups ( Chi-square 42.6, df 5, p < 0.0001). By using the volumes of the hippoc ampus, the frontal lobes or the amygdala on their alone, the correct c lassification was achieved in 88%, 65% and 58% of the subjects, respec tively. In addition, in AD patients the volumes of the left hippocampu s correlated significantly with the MMSE score and with immediate and delayed verbal memory; the smaller the volume the more impaired was th eir performance. Our data indicate that measurements of volumes of the hippocampus might be useful in diagnosis of early AD.