Moyamoya Disease

Moyamoya Disease is a rare condition affecting the major blood vessels that supply the brain.

Moyamoya Disease

For reasons we don’t yet understood, patients with Moyamoya Disease experience progressive narrowing of these major blood vessels which decreases the blood supply to the brain. 

To try to “bypass” these narrowed vessels, the brain develops alternative channels of blood supply that appear as a “puff of smoke” (the Japanese meaning of “Moyamoya”) on brain imaging. The disease increases a person’s chance of having ischemic strokes due to the inadequate blood supply and hemorrhagic strokes as a result of bleeding from the fragile Moyamoya vessels created to bypass the narrowed arteries.

How can we help you?

Our multi-disciplinary team offers the full spectrum of care for patients with Moyamoya Disease, from diagnosis to treatment to lifelong follow-up and support. Our experienced team includes fellowship-trained neurosurgeons, vascular neurologists, neuroradiologists, physician assistants, advanced practice registered nurses and therapists.


Unfortunately, patients with Moyamoya Disease are usually diagnosed after they have a stroke or transient ischemic attack (TIA). Common symptoms include:

  • Temporary weakness
  • Numbness
  • Tingling
  • Difficulty speaking
  • Headaches

Less commonly, patients may experience seizures or another asymptomatic disease. 


To diagnose Moyamoya Disease, we typically begin with non-invasive imaging studies of the brain, such as CT and MRI. We will confirm a diagnosis with a diagnostic cerebral angiogram, a catheter-based imaging study performed at the hospital as an outpatient procedure. We can also perform more advanced imaging studies to assess the severity of the disease and risk of stroke.


There is currently no effective medication to treat Moyamoya Disease. Instead, we will work with patients to carefully manage their blood pressure and may suggest taking aspirin regularly to minimize stroke risk. More definitive treatment includes providing additional blood supply to the affected areas of the brain using a surgical procedure called extracranial-to-intracranial (EC-IC) bypass.

Ayer Neuroscience Institute