[Hemiballismus. Hemichorea. Striatal infarction]

Lesions of other structures than corpus Luysii, may rarely cause hemiballism. A case is reported of hemiballism due to infarction of the territory supplied by the lenticulo-striatal arteries. CT and MR imaging showed lesions of the caudate nucleus and putamen. This suggested that the cause of the hemiballism was the suppression of the regulatory activity of the caudate nucleus on the pallidum.