Stereotactic brain biopsies in presenile dementia.

Early detection and precise diagnosis of presenile dementias are important since they determine subsequent medical care. Presently the only way to classify these syndromes is by neuropathological examination. Between 1972 and 1987, 222 stereotactic serial brain biopsies were performed in 25 selected demented patients. Comparison between preoperative clinical diagnosis and histological finding gives the following results: in 32% the clinical diagnosis has been confirmed, in 60% the diagnosis has been corrected or specified and in 8% the stereotactic brain biopsies only showed unspecific pathological gliosis.