DENTATORUBROPALLIDOLUYSIAN ATROPHY - CLINICOPATHOLOGICAL STUDY OF DEMENTIA AND INVOLVEMENT OF THE NUCLEUS BASALIS OF MEYNERT IN 7 AUTOPSY CASES

This report concerns a clinicopathological study including a quantitat ive pathological study on the nucleus basalis of Meynert (nbM) of seve n Japanese autopsy cases (four male, three female) of dentatorubropall idoluysian atrophy (DRPLA) with special reference to the clinicopathol ogical correlation of dementia in DRPLA. In each case the pattern of t he inheritance was consistent with that of an autosomal dominant trait . The neurological examination revealed that all seven individuals had cerebellar signs. Six patients had epilepsy and choreoathetoid involu ntary movement; myoclonus was evident in five patients. Dementia was n oted in all seven patients. Degeneration of the globus pallidus (parti cularly the lateral segment) and of the dentate nucleus was the princi pal pathological feature. Brain weights at autopsy ranged from 1020 to 1400 g (average 1241 g: male 1320 g, female 1135 g). The quantitative evaluation revealed no significant loss of neurons in the nbM as comp ared with a control group. There was no clinicopathological correlatio n between dementia and involvement of the nbM. We suggest that the dem entia of DRPLA is due not to the involvement of the nbM, but to - as y et - unidentified pathology elsewhere.