An electron microscopic study on atypical presenile dementia with numerous Lewy bodies in the cerebral cortex.

A report was made of an autopsied case of presenile dementia presenting the clinically characteristic symptoms of Alzheimer's disease and Pick's disease. The neuropathological findings were senile changes, namely, numerous senile plaques, neurofibrillary tangles, granulovacuolar degeneration and Pick bodies, etc., and numerous Lewy bodies in the brain stem and in the cerebral cortex. We studied mainly the ultrastructure of Lewy bodies in the cerebral cortex in this paper. The features of ultrastructural components of Lewy bodies presented types which might correspond to the various profiles of Lewy bodies observed by a light microscope. In addition, we studied the senile changes in the cerebral cortex ultrastructurally and considered that some relationship possibly existed between Lewy bodies and senile changes.