Corticostriatal Hypermetabolism in Moyamoya Disease-Induced Hemichorea: Two Case Reports and a Literature Review

Effect of low-frequency repetitive magnetic transcranial stimulation in hemichorea-hemiballismus with ipsilateral basal ganglia hemorrhage: A case report

Post-stroke hemichorea-hemiballismus (HCHB) typically manifests as hyperkinetic movements contralateral to the lesion, but rarely occurs ipsilaterally. In this article, we present a rare case who initially presented with left hemiparesis and developed right HCHB after right basal ganglia hemorrhage. To facilitate motor recovery in the left hemiparesis, we applied low-frequency repetitive transcranial magnetic stimulation (rTMS) over the left primary motor cortex. Unexpectedly, the right HCHB was significantly reduced after four weeks of therapy. Post-treatment perfusion imaging showed increased cerebral blood flow in the left middle cerebral artery territory. In conclusion, low-frequency rTMS may be considered an alternative therapy for post-stroke HCHB.

Case report: Steroid-responsive acute chorea as first presentation of the coexistence of Moyamoya and Graves' disease

Background

Chorea is a movement disorder characterized by abrupt, rapid, and uncontrollable, random movements from one part of the body to another with motor impersistence. Sporadic chorea is rarely caused by either thyrotoxicosis or Moyamoya disease (MMD).

Methods and results

In this case report, we describe a female patient with chorea with the rare coexistence of Graves' disease and Moyamoya disease. Tc-99m ethyl cysteinate dimer (ECD) brain perfusion single-photon emission computed tomography (SPECT) showed mild to moderate hypoperfusion in bilateral frontal and left temporal regions. After administering dexamethasone 20 mg for 5 days, her choreic movement symptoms recovered rapidly.

Conclusion

Although uncommon, thyrotoxicosis and Moyamoya disease can co-occur, especially in Asian female adults. Excessive thyroid hormones contribute to the dysregulation of neurotransmitters in basal ganglia-thalamocortical circuits. Moyamoya disease is responsible for ischemic changes affecting the excitatory-inhibitory circuits between the basal ganglia and the neocortex. Under a state of coexistence, thyrotoxicosis exaggerates cerebral metabolism, aggravating the impaired cerebral perfusion induced by Moyamoya disease. Moreover, inflammatory reactions caused by thyroid autoantibodies may also promote the progression of Moyamoya disease. In our experience, treatment with steroids may not only synergize the anti-thyroid effect but may also be a way to modulate the neurotransmitters within the basal ganglia or restore cerebral perfusion. We suggest that evaluation of the thyroid function status in Moyamoya disease is essential.

The Impact of Revascularization in a Patient with Atypical Manifestations of Hypoperfusion

Background and Objectives: Carotid revascularization is one of the most effective treatment options in patients with severe carotid artery stenosis causing hypoperfusion in basal ganglia. Atypical manifestations include hyperkinetic movements, noted as extremely rare. We report a case about a patient with 2-months-long complaints of Uncontrollable movements in his right side of the body subsided after carotid revascularization. Case presentation: A 71-year-old male was admitted to Pauls Stradins Clinical University Hospital with the main complaints of 2-months-long uncontrollable movements in his right hand and his right leg. When performing coordination tasks, slight inaccuracy was noted with the right-side extremities. Hyperkinetic movements—choreoathetosis in the right side of the patient’s face, arm, and leg—were seen. Computed tomography angiography revealed subocclusion in the proximal segment of the left internal carotid artery and 30% stenosis in the proximal segment of the right internal carotid artery. The patient was consulted by a vascular surgeon. Eversion endarterectomy of the left internal carotid artery was performed. The early postoperative period occurred without complications. The patient was discharged from the hospital 2 days after the surgery in good overall health condition. Two months later, choreoathetotic movements in his right side of the body had markedly decreased. No focal neurologic deficits were noted. Conclusions: Revascularization may be effective by eliminating emboli and stenosis, leading to hypoperfusion in watershed territories. A case of a 71-year-old male patient with the main complaints of 2-months-long uncontrollable movements in his right side of the body subsiding after carotid revascularization was demonstrated. It is vital to recognize atypical manifestations of hypoperfusion, associated with stenosis in internal carotid arteries, to early make a diagnosis, to perform an appropriate treatment, and to reduce the risk of cerebral infarction in the future, resulting in a longer high-quality life for the patient.