Olivary hypertrophy in a case with palatal myoclonus: light- and electron-microscopic study.

This is a report on the ultrastructural finding of the olivary hypertrophy in a case with palatal myoclonus. By light microscopy two types of neuronal changes were observed in the inferior olivary nucleus, i.e. the central chromatolysis and cytoplasmic vacuolation. Both types were also recognized by electron microscopy and the cytoplasmic vascuolation was identified as the vesiculated endoplasmic reticulum. In the reactive astrocytes, mitochondria were strikingly proliferated.