[A case of multiple cerebral infarctions associated with hemichorea induced by amantadine hydrochloride]

We report an 80-year-old woman with hemichorea probably due to amantadine hydrochloride. She visited our hospital because of gait disturbance and decreased mental activity. She was diagnosed as multiple cerebral infarctions and treated with 100 mg/day of amantadine hydrochloride. After two weeks she showed choreic movement of the face and right arm and leg. Haloperidol was administered and her choreic movement disappeared. Brain MRI showed multiple cerebral infarctions in the white matter. There was no lesion in the left basal ganglia. SPECT showed hyperperfusion in the left basal ganglia when choreic movement appeared. After choreic movement disappeared, SPECT showed no asymmetrical blood flow. These findings suggest hemichorea was related to hyperfunction of dopaminergic neurons in the left basal ganglia.