Computed tomography, electroencephalography, and clinical features in the differential diagnosis of senile dementia. A prospective clinicopathologic study.

The accuracy of computed tomography, electroencephalography, and clinical features in the differential diagnosis of senile dementia was studied prospectively. Out of 50 demented patients, autopsy revealed 32 cases with either senile dementia of the Alzheimer's type (SDAT), multi-infarct dementia (MID), or a combination of both. Eighteen patients had dementia caused by other diseases. Based on a combination of computed tomography, electroencephalography, and clinical features, senile dementia of the Alzheimer's type was differentiated from all 50 patients, with a specificity of 83% and a sensitivity of 80%. Focusing on senile dementia of the Alzheimer's type, multi-infarct dementia, or a combination of both, specificity decreased to 65% and sensitivity to 47%. Comparing the different methods, multi-infarct processes were diagnosed with a higher sensitivity by the clinical features (73%) than by computed tomography (18%) or electroencephalography (18%). None of the methods validly differentiated multi-infarct dementia from a combination of multi-infarct dementia and senile dementia of the Alzheimer's type.