Moyamoya Disease

This a progressive disorder that causes a narrowing or closing of the carotid artery or the beginning of its major branches at the base of the brain.  The primary form is heritable (autosomal dominant) and is responsible for 10% of such cases in Japan.  The secondary forms can be seen in patients with conditions such as Sickle Cell Disease, Down’s Syndrome or Neurofibromatosis or after treatments that can be complicated by an irritation of blood vessels (vasculitis) such as radiation.