Neuropathology of Parkinson's disease and related syndromes.

A progressive parkinsonian disorder predicts pathology in the substantia nigra and possibly elsewhere in the basal ganglia. Parkinson's disease is a manifestation of Lewy body disease, which is characterized by the association between Lewy bodies and cell degeneration in specific neuronal populations. Striatonigral degeneration is part of multiple system atrophy and is characterized by striatal and nigral degeneration without neuronal inclusion bodies, but glial inclusions have been described. Steele-Richardson-Olszewski disease is characterized by the globose neurofibrillary tangle and predominant brain stem pathology. Corticobasal degeneration shows similar midbrain pathology and a round, filamentous inclusion in the substantia nigra, not unlike the globose tangle, but there is also focal frontoparietal cortical atrophy. The combination of the distribution of degeneration and nerve cell morphology identify apparently distinct disorders, but most of the neuronal inclusions are not disease specific.