Essential tremor after ipsilateral cerebellar hemispherectomy: support for the thalamus as the central oscillator.

Essential tremor is a long-recognized and common movement disorder, yet controversy still surrounds its pathophysiology. The olivo-cerebello-thalamo-cortical pathway has been implicated in the genesis of essential tremor, and the inferior olive has been considered the central oscillator driving the peripheral tremor. We present the case of a patient who developed essential tremor ipsilateral to cerebellar hemispherectomy and propose that the central oscillator in patients with essential tremor may not be the inferior olive in all cases, but rather the nucleus ventralis intermedius of the thalamus.