Hemichorea-hemiballismus as the initial manifestation of symptomatic middle cerebral artery dissection: A case report

INTRODUCTION: Hemichorea-hemiballismus, which spans a spectrum of involuntary, continuous, nonpatterned movement involving one side of the body, can emerge as the initial manifestation of acute ischemic stroke. However, because of its rarity in the community, the diagnosis and treatment are often delayed. PATIENT CONCERNS: We report a unique case of a 47-year-old female who presented with acute onset hemichorea-hemiballismus. No obvious focal sign apart from involuntary, continuous, nonpatterned movement of her left arm and leg was presented. DIAGNOSIS: Initial diffusion-weighted magnetic resonance imaging (MRI) was negative but significant increase of blood flow velocity in the right middle cerebral artery (MCA) stem was revealed by transcranial doppler sonography. Repeated MRI showed acute infarction in the contralateral globus pallidus. Isolated dissection of the right MCA typified by intimal flap with double lumen was identified by digital subtraction angiography and high-resolution magnetic resonance imaging (HR-MRI). INTERVENTIONS: The patient was initially treated with dual antiplatelet agents but the uncontrollable movement deteriorated during hospitalization. Antithrombotic therapy was then intensified with combination of tirofiban and low-molecular-weight heparin. Other symptomatic treatment included volume expansion with colloidal fluid to improve cerebral perfusion. Her involuntary movement gradually diminished and the patient was discharged with rivaroxaban 15 mg/daily. OUTCOMES: The patient had recovered with significant reduction in her hemichorea-hemiballismus. Three-month follow-up HR-MRI showed complete resolution of the MCA dissection lesions. CONCLUSION: Prompt recognition of acute onset hemichorea-hemiballismus as the manifestation of acute ischemic stroke in appropriate clinical setting may reduce diagnostic delay. Multiple imaging techniques including cerebral digital subtraction angiography and HR-MRI can be applied to diagnosis and further clarify the mechanism of stroke, which facilitate in selection of secondary prevention therapies.