Moyamoya and extracranial vascular involvement: fibromuscular dysplasia? A report of two children.

We present two patients with moyamoya syndrome and the unusual involvement of extracranial vessels. The first case illustrates the rare association between moyamoya and primary pulmonary hypertension. In the second patient, moyamoya was complicated by stenoses of vertebral, renal, and mesenteric arteries. In both cases, a systemic intima-proliferative disease, such as fibromuscular dysplasia (FMD), was suspected to be the cause of both intracranial and extracranial arterial disease.