Congenital Hypoplasia of Bilateral Internal Carotid Artery with Migraine-Like Headache with Aura

To the Editor： A 36-year-old man with intermittent migraine-like headache with aura for 20 years underwent cerebrovascular computed tomography angiography （CTA） revealing very small calibers of bilateral internal carotid arteries （ICAs） in other hospital. He was admitted to our hospital for further examination several days later. He had no vascular risk factors, and no family history of atherosclerotic or cerebrovascular diseases. On admission, general physical and neurological examinations were normal and vascular systolic murmur was not detected in the neck. Blood tests, including items relevant to diabetes, dyslipidemia, and vasculitis, were unremarkable.