Hokkaido University Moyamoya Center

Hokkaido University Moyamoya Center


The Hokkaido University Moyamoya Center consists of experienced neurosurgeons, neuro-radiologists, nurses, and rehabilitation physicians and therapists. We have been leading the clinical treatment and research of this rare disease around the world.


Moyamoya disease can affect both children and adults. Episodes of weakness in a limb or on one side of the body are the most typical clinical mode of presentations. Moyamoya disease can cause motor and sensory deficit, headaches, speech disturbances, seizures and cognitive dysfunction. There are currently no effective drug treatments. Surgical revascularization has been proven to be the only effective treatment to reduce the risk of subsequent stroke.


Our center has been employing the most effective and yet technically demanding revascularization procedures (both direct and indirect bypass combined) for more than 25 years. Therefore, we are confident of offering excellent care to patients and their families. We have also conducted both clinical and basic researches. Our moyamoya team has been working eagerly with patients and their families who travel to Hokkaido from all over the world. To learn more about treatments for moyamoya disease, please contact us via e-mail.


Email: nougeka4@pop.med.hokudai.ac.jp


About Moyamoya disease

Moyamoya disease is an uncommon cerebrovascular disorder that is characterized by progressive stenotic change in the terminal portion of the bilateral internal carotid arteries and the formation of an abnormal fine vascular network (the moyamoya vessels) at the base of the brain. The appearance of this vascular network on an angiogram looks like a puff of cigarette smoke drifting in the air; thus, in 1969, Suzuki et al named this novel disorder “moyamoya disease” because the word “moyamoya” means “puff of smoke” in Japanese.


There are two main onsets of age at which the risk of developing moyamoya disease peaks: higher peak at around 5 years of age and the lower one at around 40 years of age. Most children with moyamoya disease develop transient ischemic attack (TIA) or cerebral infarction, whereas about half of adult patients develop intracranial breeding, and the other half develop TIA, cerebral infarction, or both. People of Asian background have higher incidence of Moyamoya disease and intracranial hemorrhage in their childhood compared to that of white people.


Although some genetic and environmental factors are associated with the cause of moyamoya disease, the actual cause is unknown. About 15% of all moyamoya disease cases are considered familial and the incidence is regionally different with a high occurrence in Asian countries. In Japan, the annual prevalence and incidence have been estimated at 3.16 and 0.35 per 100,000, respectively. Enthusiastic genetic researches have been conducted and the results showed remarkable progress in the past several decades. Several studies suggested that moyamoya disease is probably inherited in a polygenetic or autosomal dominant mode with a low penetrance.


Moyamoya disease is also associated with various disease entities including atherosclerosis, autoimmune disease, meningitis, and other diseases of known generic origin such as neurofibromatosis type 1 and Down Syndrome. These are referred to as “quasi-moyamoya disease” and its incidence is also higher in Asian countries than in Western countries.