Moyamoya Disease

Moyamoya disease is a condition in which the walls of the carotid arteries thicken and the arteries narrow, restricting or blocking blood flow to the brain. In response, the body grows many new blood vessels to compensate for the blockage. However, this compensation is often not sufficient, and the reduced blood flow and formation of blood clots associated with moyamoya can cause a stroke.

If a patient is experiencing stroke symptoms, emergency care is essential.

“Moyamoya” is Japanese for “puff of smoke,” and refers to the appearance of these networks of new blood vessels on a cerebral angiogram.

There is no known cause for this disease. However, women are more likely to be diagnosed with moyamoya, and in about 6 to 12 percent of cases, there is a family history of the disease.


Moyamoya symptoms first appear with an ischemic stroke, hemorrhagic stroke, or transient ischemic attack (TIA or “mini” stroke). During an ischemic stroke or TIA, a blockage interrupts the flow of oxygen-carrying blood to the brain. Hemorrhagic stroke results when the tiny, abnormal blood vessels burst and bleed into the brain.

With ischemic and hemorrhagic stroke, you may experience symptoms such as weakness or numbness in an arm or leg, difficulty speaking, or paralysis affecting one side of your body. Other symptoms include seizures and cognitive or learning impairments. You may also experience headache with a hemorrhagic stroke.

While the exact cause of moyamoya is unknown, about one in 10 individuals with the disease has a close relative who is also affected, implying that in these cases moyamoya is the result of inherited genetic abnormalities.

Why Choose UT Southwestern?

UT Southwestern treats moyamoya disease in adults and children (in connection with Children’s Health). We have three highly skilled neurosurgeons who can perform the procedures associated with moyamoya. This makes UT Southwestern unique; because moyamoya is quite rare, many institutions are unable to offer care, or may have only one neurosurgeon who’s qualified to treat it.

In addition, our neurosurgeons have the benefit of working with a team of neurologists, neuroradiologists, and many other brain disorder specialists who have decades of experience evaluating and treating moyamoya. The team discusses each patient case together before beginning any treatment.

Institutions throughout the state and surrounding areas refer their moyamoya patients to us because of our team’s level of expertise and the wealth of evaluation and treatment options that UT Southwestern offers.

Our Services

If you’ve been diagnosed with moyamoya disease, or are experiencing symptoms that may be associated with it, our team can help.

We’ll conduct imaging studies to determine or confirm a diagnosis. We’ll also perform a neuropsychological assessment to help us determine any cognitive changes you may be experiencing. This gives us a baseline of cognitive abilities before we set a treatment plan (which is likely to include surgery).

After treatment, we offer a dedicated neurocritical care unit (neuro ICU) for brain disorder patients, as well as neurorehabilitation services, all in the same building.

Request an Appointment

To schedule an appointment with a moyamoya specialist at UT Southwestern’s facilities in Dallas, or to learn more about our services, request an appointment or call 214-645-8300.