[Hemichorea improved by carotid artery stenting in a 73-year-old man with hypoperfusion of the basal ganglia].

A 73-year-old man presented with continuous hemichoreic movement of right arm and leg and with dyskinesia in his tongue. Magnetic resonance image (MRI) showed no ischemic lesion within the basal ganglia, but magnetic resonance angiography (MRA) and carotid duplex ultrasonography showed the left internal carotid occlusion and 80% stenosis in the right common carotid artery. Tc-99m-ECD-SPECT showed hypoperfusion of the frontal lobe, temporal lobe, parietal lobe, basal ganglia and thalamus. A trial of haloperidol had no effect; therefore, the right carotid artery stenting was performed. Hypoperfusion in the left internal carotid artery area was improved by cross flow from the right side, and his hemichorea gradually improved. This result supports the notion that hypoperfusion-related hemichorea may occur, even in the absence of cerebral ischemia.