Gelb et al listed criteria for the histologic examination of the brain at autopsy to confirm the clinical diagnosis of Parkinson's disease. This can help clarify uncertain cases and exclude secondary causes. The authors are from the University of Michigan and the National Institute of Neurological Disorders and Stroke.
Histologic features:
(1) Examination of the substantia nigra shows marked nerve cell loss with gliosis.
(2) Examination of the substantia nigra and locus ceruleus shows at least 1 Lewy body.
(3) Exclusion of other disorders that may be confused with Parkinson's disease.
The absence of Lewy bodies requires none being found in 4 nonoverlapping sections from the substantia nigra and 4 nonoverlapping sections from the locus ceruleus.
