Published online Jul 6, 2021. doi: 10.12998/wjcc.v9.i19.5287
Peer-review started: February 15, 2021
First decision: March 11, 2021
Revised: March 31, 2021
Accepted: May 6, 2021
Article in press: May 6, 2021
Published online: July 6, 2021
Processing time: 128 Days and 22.2 Hours
Hemichorea usually results from vascular lesions of the basal ganglia. Most often, the lesion is contralateral to the affected limb but rarely, it may be ipsilateral. The pathophysiology of ipsilateral hemichorea is still poorly understood. We review the literature on hemichorea due to ipsilateral cerebral infarction and explore possible mechanisms for its occurrence.
A 72-year-old woman presented with complaints of involuntary movements of the muscles of the left side of the face and mild weakness of the right limbs. Her symptoms had started suddenly 1 d earlier. After admission to the hospital, the involuntary movements spread to involve the left limbs also. Magnetic resonance imaging revealed a left thalamic infarction. The patient’s hemichorea subsided after treatment with haloperidol (2 mg per time, 3 times/d) for 3 d; the hemiparesis resolved with rehabilitation physiotherapy. She is presently symptom free and on treatment for prevention of secondary stroke. We review the literature on the occurrence of ipsilateral hemichorea following thalamic infarction and discuss the possible pathomechanisms of this unusual presentation.
Ipsilateral hemichorea following a thalamic stroke is rare but it can be explained by structure of the extrapyramidal system. The thalamus is a relay station that exerts a bilateral control of motor function.
Core Tip: Acute hemichorea is usually caused by lacunar infarcts in the contralateral basal ganglia. We present a case of hemichorea due to ipsilateral thalamic infarction. A 72-year-old woman was admitted to our hospital with unilateral hemichorea and contralateral hemiparesis. Magnetic resonance imaging revealed a left thalamic infarction. The hemiparesis improved with rehabilitation physiotherapy, and the hemichorea subsided following treatment with haloperidol. The mechanism of ipsilateral hemichorea is poorly understood, but it could be because some fibers of the extrapyramidal system continue their ipsilateral course, passing through the thalamus, which is a relay station exerting control over motor function of both sides.