Moyamoya Disease

Call Us Toll Free:


Toll-Free: 866.588.2264

Moyamoya disease is a rare neurological disorder involving the progressive narrowing of two of the major arteries (internal carotid arteries) supplying blood to the brain. As a result of this progressive narrowing, a new network of small blood vessels form around the base of the brain in an attempt to compensate for the reduced blood flow. The appearance of this new network of blood vessels resembles a “puff of smoke” on cerebral angiogram giving rise to the name “moyamoya” - from the Japanese expression for something “hazy just like a puff of smoke drifting in the air.” In many instances, this new vessel formation is insufficient to compensate for the progressive occlusion and blockage of the internal carotid arteries resulting in transient or permanent brain damage (see symptoms below). Although a high incidence of Moyamoya disease is found in people of Asian descent, especially Japanese, it has now been recognized world-wide, and in all ethnic groups. It appears to be more common in females and is more common in children accounting for about 6% of childhood strokes in Western counties. Adult onset may also occur. The etiology or cause of Moyamoya disease is unknown, although rare familial cases have suggested a genetic influence (and three genes have tentatively been identified in primary Moyamoya disease).

Moyamoya syndrome (or “secondary” Moyamoya) is different from primary or idiopathic Moyamoya disease as it develops secondary to an underlying disorder such as Down syndrome, sickle cell disease, William syndrome, or neurofibromatosis, or may occur after brain radiation therapy.

What do you want to do next?

Refer a Patient

800.553.5056 Available 24 hours a day

Request an Appointment

216.636.5860 call locally.

866.588.2264 call toll-free.

Cleveland Clinic Mobile Site