INVOLUNTARY TONIC SPASMS OF A LIMB DUE TO A BRAIN-STEM LACUNAR INFARCTION

Background and Purpose Although repetitive involuntary movements are a well-recognized manifestation of carotid occlusive disease, similar m ovements have not been reported with a lacunar infarction outside of t he basal ganglia or subthalamic nucleus. We describe a man with tonic spasms associated with a lacunar infarction in the right ventral pons. Case Description Involuntary tonic spasms of a paretic limb developed acutely in a 69-year-old hypertensive man with a clinical presentatio n of pure motor hemiparesis. Magnetic resonance imaging demonstrated a lacunar infarction of the ventral pons. There was no evidence for car otid occlusive disease. An electroencephalogram recorded during the mo vements showed no abnormality. The abnormal movements responded well t o treatment with oral diazepam. Conclusions A brain stem lacunar infar ction may be associated with involuntary tonic limb spasms clinically similar to those reported as paroxysmal symptoms of multiple sclerosis .