MIDBRAIN NEUROPATHOLOGY IN IDIOPATHIC PARKINSONS-DISEASE AND DIFFUSE LEWY BODY DISEASE

We have quantified midbrain cell loss in idiopathic Parkinson's diseas e (Pi)) compared with controls; six patients had PD with onset before 70 years, five patients had late onset PD (>70 years) and nine patient s had diffuse Lewy body disease. The pattern of cell loss in these las t two groups has not been previously described. No age associated neur onal loss was seen in controls. There was cell loss and reduced area o f the pars compacta in all cases but no difference in the pattern of c ell loss, which was predominantly ventral. The amount of cell loss in the dorsolateral cluster correlated with the duration of Parkinsonian symptoms, while greater cell loss in the dorsomedial cluster correlate d with the presence of tremor and the absence of early dementia. These results suggest that the topography of midbrain pathology does not as sist in differentiating these overlapping syndromes. (C) Pearson Profe ssional 1996