Unusual cases of presenile dementia with Fahr's syndrome.

Three patients with an unusual type of presenile dementia were studied. Atypical clinical pictures emerged from an evaluation of these cases. Their symptoms and signs were thought to be neither those of Alzheimer's disease nor those of Pick's disease but a partial mixture of those of both diseases. The neuropathological changes were characteristic and the common findings were as as follows: the absence of senile plaques, the widespread presence of numerous neurofibrillary tangles, a calcareous deposition of Fahr's type, a circumscribed cerebral atrophy in the temporal or/and frontal lobes, a moderate or severe demyelination and fibrous gliosis in the white matter of the atrophied areas, and a slight or moderate neuronal loss in the nucleus basalis of Meynert. Similar cases reported previously were reviewed.