Hemichorea in hyperglycemia associated with increased blood flow in the contralateral striatum and thalamus.

We studied a patient with hyperglycemia who developed choreic involuntary movements in the right extremities using single photon emission computed tomography (SPECT) with 123I-N-isopropyl-p-iodoamphetamine. SPECT revealed an increased blood flow in the left striatum and thalamus. Through the control of blood glucose and the administration of haloperidol, the hemichorea was resolved, and the increased blood flow in the striatum and thalamus disappeared. These findings suggest that the increased blood flow, which probably indicates increased neuron activity in the striatum and thalamus, is an underlying pathophysiological state in hemichorea.