Bulbar myoclonus without palatal myoclonus. A hypothesis on pathophysiology

A 40-year-old woman with myoclonic contractions bilaterally in the infrahyo id neck muscles, especially in the left cricothyroid muscle, was presented and successfully treated with botulinum toxin injections. The patient had a nide, aberrant vessel curving into the left dorsolateral reticular formati on of the medulla oblongata. Based on our observations, we propose that sym ptomatic bulbar and palatal myoclonus is caused by pathology in the dorsola teral reticular formation, and not by inferior olivary dysfunction as is cu rrently thought. Eur J Neurol 6:367-370 (C) 1999 Lippincott Williams & Wilk ins.