Acute hemichorea as an unusual presentation of internal carotid artery stenosis

Abstract

Involuntary movement associated with deep watershed ischemic lesions has been rarely reported. A 67-year-old woman presented with acute hemichorea on the left side. Magnetic resonance imaging showed acute infarcts in the anterior border zone. On perfusion studies, impaired cerebral blood flow was observed on the subcortical region sparing the basal ganglia. Cerebral angiogram confirmed severe stenosis in the right internal carotid artery. Her hemichorea gradually improved along with normalization of perfusion after carotid artery stenting with angioplasty. We suggest that impaired cerebral blood flow in critical watershed territories may be an important contributing factor in hemichorea associated with carotid occlusive disease.

Keywords: Carotid stenosis; Hemichorea; Perfusion weighted MRI; Stents.

Figure 1.

Diffusion-weighted (A) and fluid-attenuated inversion recovery (B) MR images demonstrate acute small infarctions in the right border zone between the anterior and middle cerebral artery.

Figure 2.

Pre-stenting perfusion-weighted MR scans (A) show delayed mean transit on the subcortical area around the infarcted lesions. No definite evidence of hemodynamic insufficiency was found in the basal ganglia. Post-stenting follow-up perfusion images (B) demonstrate improvement of brain perfusion abnormalites in the right hemisphere.

Figure 3.

The lateral view of the right carotid artery angiogram (A) demonstrates severe (90%) stenosis with atherosclerotic ulcer in the right internal carotid artery. Post-stenting angiogram (B) shows successful recanalization of the carotid lesion.