[Fibromuscular dysplasia of the basilar artery presenting as cerebral infarction in a young female].

We reported a 20-year-old woman with fibromuscular dysplasia (FMD) of the basilar artery presenting multiple cerebral infarctions. A sudden onset of consciousness disturbance and right hemiparesis was experienced. A neurological examination on day 2 revealed an absence of light and corneal reflexes on the left side, homonymous left upper quadrant anopsia and right hemiparesis with Babinski sign: she was also somnolent. On head MRI, multiple high signal intensity lesions were seen in the right occipital lobe, bilateral thalami and left pons on T2- and diffusion weighted images. Brain angiogram revealed the string of beads sign of the basilar artery, suggesting FMD. Neurological deficits gradually improved in the 2 months that followed, leaving slight hemiparesis and homonymous left upper quadrant anopsia In the following 3 years, no recurrence was seen with aspirin (81 mg/day). FMD in the head and neck usually affects extracranial segments of the carotid and vertebral arteries, while FMD of the basilar artery is extremely rare. To the best of our knowledge, 12 cases with FMD of the basilar artery have been reported; of these, 11 were symptomatic and 5 died. Since FMD of the basilar artery has poor prognosis, attention needs to be paid for FMD in young adults as a differential diagnosis of cerebral infarction in the territory of the basilar artery.