At the Moyamoya Center at the Northwell Health Neuroscience Institute, our multidisciplinary team is dedicated to the diagnosis, treatment and support of patients and their families with Moyamoya disease. Members of our team include a vascular neurologists, neuropsychologists ,neurosurgeons, endovascular specialists, neuroscience nurses and nurse practitioners and physician assistants.
Understanding Moyamoya Disease
Moyamoya is a rare, cerebrovascular disorder caused by the progressive blockage (occlusion) of the large branches of the internal carotid artery at the base of the brain in an area called the "circle of Willis". To feed the starved cerebral tissue caused by Moyamoya disease, the body forms a network of dilated and weakened (friable) blood vessels.
Moyamoya disease is most commonly seen in patients of Asian descent. However, patients of all races can develop the disease. In Asia is most commonly seen in children and young adults and is typically diagnosed in children 10 years of age and younger, as well as in adults (more commonly women) in their 30's. In North America the disease is seen more commonly seen in adults in their third and fourth decade and is noted to be most common in women particularly in the African American and Hispanic populations.
The appearance of Moyamoya disease on diagnostic imaging tests is sometimes seen along with other medical conditions. When the changes in the brain blood vessels are associated with another underlying medical problem, the condition is termed Moyamoya syndrome. Medical conditions that are associated with Moyamoya syndrome include:
- Sickle cell anemia
- Neurofibromatosis type 1
- Down syndrome
- Certain congenital heart defects
- Previous brain radiation therapy
- Giant craniofacial hemangiomas
The most common initial Moyamoya disease symptoms in children consist of transient, or temporary, episodes of muscle weakness or paralysis on one side of the body, sometimes alternating sides between episodes. These symptoms are caused by transient ischemic attacks (TIAs) or small ischemic strokes. Some children may experience seizures or involuntary movements and even exhibit signs of mental retardation. In young patients, Moyamoya disease can also present with headaches, speech difficulties, hemorrhage and anemia.
The most common Moyamoya disease symptom in adults is intracranial hemorrhage, or bleeding within the skull. Disturbances of consciousness or subarachnoid hemorrhaging (bleeding in the connective tissue covering the brain) are also common symptoms. In North American Moyamoya, adults present more commonly with ischemic or non hemorrhagic stroke but can present with intracranial bleed as well.
Diagnostic tests for Moyamoya disease and Moyamoya syndrome, include MRI (magnetic resonance imaging) and diagnostic cerebral angiography (X-ray images of the inside of the cerebral blood vessels), along with tests to assess cerebral blood flow, including SPECT imaging, a nuclear medicine study and quantitative MRA imaging.
Quantitative flow MRA is a diagnostic test used during the pre-treatment evaluation. Nova® qMRA is non-invasive and produces a fully rotating 3D model to show the blood vessels from every angle. The resulting report and blood vessel images show blood flow volume, velocity and direction.
What are the treatments?
The only surgical treatment is revascularization of the brain utilizing either an indirect or direct vascular graft.
What is the procedure for diagnosis and treatment?
- Diagnostics. Patients are evaluated by our clinical staff and then are required to complete a three-component diagnostic evaluation including hemispheric perfusion imaging, MRI and MRA with NOVA® vessel flow testing and diagnostic angiography. Neuropsychological evaluation is also considered.
- Conferencing. Patient testing is reviewed in a multidisciplinary cerebrovascular conference held twice weekly and a treatment recommendation is made.
- Treatment. Patients are recommended to undergo either surgical revascularization or conservative management.
- Follow-up. Surgical patients require follow-up MRA imaging at three months and angiography at six months. Medical patients have their follow-up tailored to their unique presentation and subsequent symptom pattern.
What will I receive after my consultation?
Each patient receives a podcast of his or her imaging with a full explanation of the treatment plan.