NIH

Zebra of the Week: Moyamoya disease

January 20, 2025

Moyamoya disease is a rare intracranial arteriopathy involving progressive stenosis of the cerebral vasculature located at the base of the brain. Moyamoya means “puff of smoke” in Japanese and is used to describe the tangled appearance of tiny vessels compensating for the stenosis. The disease primarily affects children, but can also occur in adults. In children, the first symptom of moyamoya disease is often stroke or recurrent transient ischemic attacks (TIAs) that are frequently accompanied by muscular weakness or paralysis affecting one side of the body. Adults may also experience these symptoms that arise from blocked arteries, but more often experience a hemorrhagic stroke. Other symptoms may include headaches, seizures, impaired consciousness, involuntary movements, vision problems, cognitive and/or sensory impairment.

• Population estimate: Fewer than 5,000 people in the U.S. have this disease.
• Symptoms: May start to appear at any time in life.
• Cause: The Genetic and Rare Diseases Information Center doesn't currently have information about the cause of this disease.

Sources:

NIH GARD. (Accessed 2025, January 17). Moyamoya disease. https://rarediseases.info.nih.gov/diseases/7064/moyamoya-disease

National Institute of Neurological Disorders and Stroke (NINDS). (Accessed 2025, January 19). Moyamoya disease. https://www.ninds.nih.gov/health-information/disorders/moyamoya-disease