Anatomical Pathology

Parkinson's disease is characterized by the destruction and loss of pigment of the substantia nigra: normally, the substantia nigra appears black however in Parkinson’s disease this black pigment is lost. More specifically it is the ventral part of the pars compacta where most cell death occur.

Image courtesy of https://en.wikipedia.org/wiki/File:Lewy_Body_alphaSynuclein.jpg

 Some studies have hypothesized that Lewy bodies represent the presymptomatic phase of Parkinson disease. Alpha-synuclein is a major structural component of Lewy bodies. Lewy bodies themeselves are concentric, eosinophilic, cytoplasmic inclusions with peripheral halo like structures and dense cores. Although the presence of Lewy bodies within pigmented neurons of the substantia nigra is characteristic of parkinson’s disease it is not, pathognomonic of (IPD). Lewy bodies can also found in the cortex, nucleus basalis, locus ceruleus, intermediolateral column of the spinal cord, and other areas. As well as the different areas of production in the brain and spinal cord, Lewy bodies are not specific to Parkinson disease, as they are found in some cases of atypical parkinsonism, including Hallervorden-Spatz disease.

Image courtesy of https://en.wikipedia.org/wiki/File:Lewy_Body_alphaSynuclein.jpg