Distribution of neuronal cytoplasmic inclusions in multiple system atrophy.

Neuronal cytoplasmic inclusions (NCIs) were demonstrated by means of silver staining (Gallyas staining) in the central nervous systems of 18 deceased patients with multiple system atrophy (MSA) - 6 with olivopontocerebellar atrophy (OPCA), 6 with striatonigral degeneration (SND) and 6 with Shy-Drager syndrome (SDS). We observed NCIs in the cerebral cortex, putamen, pons, medulla oblongata and spinal cord, and especially in the putamen and pons of all cases with MSA. No NCIs were observed in the cerebellum and midbrain. The findings were common to all 3 subtypes of MSA. NCIs were not present in patients with other neurodegenerative disorders and non-neurological disorders. Our findings indicate that NCIs represent a special neuronal alteration characteristic of MSA and support the theory that OPCA, SND and SDS represent manifestations of a single condition i.e. MSA.