Palatal "myoclonus" and inferior olive hypertrophy with one-sided cerebellar lesion. Clinico-pathological report of one patient.

A case of palatal myoclonus and inferior olive hypertrophy is reported. Lesions located other than in the medulla were cerebellar infarction, lymphomatous infiltrates and, supratentorially, progressive multifocal leukoencephalopathy. It is suggested that double innervation of the olives from either side dentate nucleus may be why in the case reported here and in several cases in the literature, one-sided supra-olivary lesions can produce bilateral hypertrophy. As with palatal "myoclonus" and olivary hypertrophy, it is proposed that if the characteristic rhythmical movements occur, lesions besides those along the dentate-olivary pathway and the olivary hypertrophy itself have to be present.