A 45 year old Japanese woman with atherosclerosis and Graves' disease presents with recurrent hemorrhagic stroke. She has no known risk factors: no hypertension, no alcohol, no dyslipidemia, and no trauma. CT shows dilatation of sulci and focal ventricular enlargement suggesting chronic disease. MRI shows dilated collateral vessels in the basal ganglia and thalamus. Angiography is shown above.
Challenge: This is a "double name." What is the cause of the hemorrhagic strokes?
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