[Resting tremor of Parkinson's disease changing into Holmes' tremor by cerebellar hemorrhage: an examination of the pathophysiological mechanism of tremor].

Abstract

A 71-year-old male who suffered from Hoehn and Yahr stage III Parkinson's disease with bradykinesia, rigidity and a 5-6-Hz tremor at rest in the right extremities was admitted to our hospital due to the sudden onset of vertigo. Right cerebellar hemorrhage was confirmed by CT. The patient's resting tremor in the right extremities disappeared immediately following the cerebellar hemorrhage. Six days later, MRI showed Wallerian degeneration in the cerebello-rubro-thalamic tract. Approximately 5 months later, a 2-3-Hz Holmes' tremor gradually appeared in the right upper extremity. This tremor was improved by increasing L-dopa doses. Case reports of the disappearance of Parkinson's resting tremor and subsequent emergence of Holmes' tremor due to cerebellar lesion are rare. Furthermore, the Wallerian degeneration of the cerebello-rubro-thalamic tract identified on MRI between tremors of the different frequencies is very rare. We hypothesize that the cause of the tremor frequency change was simultaneous damage to the nigro-striatal network and the cerebello-thalamo-cerebral network.