Corticonigral degeneration with neuronal achromasia. A clinicopathologic study of two cases.

We describe the clinical and neuropathological features of two patients having corticonigral degeneration with neuronal achromasia (CND). Both patients had cognitive decline and movement disorders. Magnetic resonance (MR) scans showed cortical atrophy, which in one case was most prominent in the parasylvian region, and ventricular enlargement in both cases. Neuropathological examination revealed swollen achromasic neurons within the cerebral cortex and marked neuronal loss in the substantia nigra. No Pick bodies, Lewy bodies, histologic changes of Alzheimer's disease, or spongiform change were present in either case. The diagnosis of CND should be considered in patients with complex movement disorders, with or without abnormalities in cognitive function.