QUANTITATIVE MAGNETIC-RESONANCE-IMAGING AND NEUROPSYCHOLOGICAL FUNCTIONS IN DEMENTIA OF THE ALZHEIMER-TYPE

Background. The aim of the present study was to investigate neuropsych ological functions in dementia of the Alzheimer type (DAT) with respec t to morphological changes that were revealed by quantitative magnetic resonance imaging (MRI). Methods. Twenty patients with DAT (NINCDS-AD RDA criteria) and 10 healthy age and sex matched controls were include d. The neuropsychological function was evaluated on a test battery cov ering the severity of dementia, verbal and visual memory, concentratio n and attention, language skills and general intelligence as well as a ctivities of daily living. 3D MRI sequences were acquired using a 1.5 T Siemens MAGNETOM. Whole brain volume, total intracranial volume (TIV ), volume of the frontal and temporal lobes and volumes of the amygdal ahippocampus complex (AHC) were assessed using the newly developed sof tware NMRWin. Results. Apart from TIV all morphometric parameters diff ered significantly between the diagnostic groups. AHC volumes discrimi nated best between the groups, with only a small overlap. AHC atrophy exceeded generalized atrophy. These findings were confirmed when the d ata were reanalysed after dividing the DAT patients into a mildly and moderately affected group. The severity of dementia was significantly correlated with the volumes of the AHC and the volumes of the temporal lobes bilaterally, but not with the whole brain volume and the volume s of the frontal lobes. Conclusions. These results underline the impor tant role of the temporal substructures for aetiology and progression of DAT. They indicate that the volume of the AHC can be monitored by M RI and may be used to follow up the disease process.