Significance of cerebellar Purkinje cell loss to pathogenesis of essential tremor

Abstract

Some recent studies indicate that most essential tremor (ET) cases have cerebellar pathology characterized by Purkinje cell (PC) loss and its sequelae. Objective To assess the role of PC degeneration in ET symptomatology. Methods We studied seven ET, six tremor dominant Parkinson’s disease controls and two normal control brains. Cerebellar PC counts were done in all cases by a neuropathologist using three different methods to identify PC. Results There were individual differences in PC counts in all subgroups. There was no difference between ET and controls of the same age. The PC count in ET was not related to: onset site of ET, severity of symptoms, or any other clinical features that we studied but there was a trend to a reduced number of PC with age in all groups. Conclusion There is no evidence in our study or in the literature to date indicating that PC loss is the pathological basis of ET. Further studies are needed to determine the pathophysiology of ET.