Hemichorea-hemiballismus caused by lacunar infarction in the basal ganglia. A case report.

Unilateral hemichorea-hemiballismus developed suddenly in a 60-year-old man. Computed tomography revealed a small area of low density in the region of the left anterior limb of the internal capsule and the head of the caudate nucleus which was consistent with a lacunar infarction. Haloperidol gradually abolished the symptoms within 7 days of their onset. No further choreoballistic movements were experienced. This report reveals that ballistic movements may occasionally be caused by lesions lying some distance from the subthalamic nucleus of Luys.