Acute Ischemic Stroke in Moyamoya Syndrome Associated with Thyrotoxicosis

BACKGROUND: A few cases of moyamoya syndrome associated with thyrotoxicosis have been reported. However, studies on the association of hyperthyroidism with moyamoya syndrome are insufficient. CASE REPORT: Here we report a case of hyperthyroidism associated with moyamoya syndrome in a 41-year-old woman with aphasia and right side weakness. Brain imaging revealed acute cerebral infarction of left middle cerebral artery territory and occlusion of bilateral distal internal carotid arteries. CONCLUSION: Antithyroid medication stabilized the patient's neurologic deterioration, suggesting that thyrotoxicosis could aggravate acute cerebral infarction caused by moyamoya syndrome.