Top Things to Know: Adult Moyamoya Disease and Syndrome: Current Perspectives and Future Directions
Published: August 23, 2023
Prepared by Anne Leonard MPH, RN, FAHA National Senior Director Science and Medicine
- Adult Moyamoya disease (MMD) and syndrome is a rare disorder and carries a significant morbidity and mortality. This disorder also has numerous ambiguities in identification and in therapy.
- Moyamoya disease is a cerebrovascular steno-occlusive condition characterized by progressive stenosis of the terminal portion of the internal carotid artery and the formation of an abnormal network of dilated, fragile perforator vessels at the base of the brain.
- Moyamoya syndrome (MMS) includes diagnostic criteria for moyamoya disease but has other associated comorbidities that are associated with vasculopathy including autoimmune disease, meningitis, brain tumors, Down syndrome, neurofibromatosis type I, head irradiation and sickle cell disease.
- Upwards of 12% of patients with MMD have a positive family history suggesting a strong genetic component.
- This disorder is most prevalent in Asia especially in Japan. In the United States the National Impatient Sample between 2002-2008 showed an incidence of 0.57 per 100,000 people per year; the mean age at diagnosis was 32 years and the ratio of women to men impacted is almost 3 to 1. It is seen in all race-ethnic groups.
- Clinical manifestations or events of MMD and MMS can be broad and include neurological ischemic events (e.g., transient ischemic attacks or strokes), neurological hemorrhagic events (e.g., intracerebral, or intraventricular), other neurological symptoms (e.g., headaches/migraines or other), and symptoms associated conditions (e.g., autoimmune disorders or other).
- Cerebral vascular imaging is an important diagnostic tool. Digital subtraction angiography and MRI/MRA are used to assist in making the diagnosis by identifying stenotic vessels.
- Antithrombotic and thrombolytic use in ischemic MMD includes oral antiplatelets vasodilators (cilostazol), and intravenous thrombolysis with tissue plasminogen activator.
- Surgical interventions for moyamoya consists of revascularization procedures and are. discussed in this statement.
- More research is needed to understand several outstanding issues related to MMD and MMS, including improved diagnostic criteria, validation of biomarkers, determining pathophysiological processes involved and generation of conclusive evidence to provide better guidelines for treatment.