Rationale: Chorea is a movement disorder characterized by randomly appearing involuntary movements of the face, neck, limbs, or trunk. Hemichorea is unilateral, involving one side of the body. Hemichorea is commonly caused by non-ketotic hyperglycemia and/or cerebrovascular injury to the contralateral basal ganglia.
Patient concerns: Here, we report the case of a patient diagnosed with hemichorea who had diabetes, cavernous angioma, and a small intracranial errhysis. Routine testing showed the patient's blood glucose level was slightly higher than the normal range.
Interventions: The errhysis was too small to be treated.
Diagnoses: Brain magnetic resonance imaging showed a cavernous angioma with a small errhysis in the right putamen.
Outcomes: Hemichorea was completely resolved after 4 months.
Lessons: If diabetes is well controlled and imaging indicates brain lesions suggestive of a recent stroke, a diagnosis of post-stroke hemichorea should be considered.