Dementia without Alzheimer pathology.

We studied five demented patients who, on neuropathologic examination, had cell loss and Lewy bodies in substantia nigra and locus ceruleus and few Alzheimer-type changes. The nucleus basalis had minimal cell loss in three patients and was not available in two. The lesions in the substantia nigra and locus ceruleus were unlikely to account for the dementia, and other structural or biochemical derangements, probably cortical but possibly subcortical, must also have been present but not visible at the light microscopic level.