It is a rare and progressive disease of the brain caused by narrowing or blocking of the carotid artery, which supplies the brain with blood. Moyamoya disease can cause a variety of neurological symptoms, including headache, seizures, weakness, vision problems, speech difficulties, and cognitive decline. It reduces blood flow to the brain and increases the risk of stroke or bleeding. People of Asian descent and children are more likely to contract Moyamoya disease.
It is unknown what causes moyamoya disease, but genetics or certain medical conditions could play a role. Some people with moyamoya disease have a family history of the disorder, suggesting a genetic predisposition. As well as other blood vessel disorders, moyamoya disease can also be associated with:
Down syndrome
Anemia of sickle cell
Type 1 neurofibromatosis
Thyroid hyperfunction
The symptoms of moyamoya disease vary depending on the age of the person and the severity of the blood vessel narrowing. The most common symptoms in children are strokes and transient ischemic attacks (TIAs), which interrupt the blood flow to the brain temporarily. A stroke or a TIA can cause sudden and temporary weakness, numbness, or paralysis on one side of the body, face, or limbs. It can also cause vision problems, difficulty speaking, and loss of consciousness. The most common symptom of moyamoya disease is bleeding in the brain, which can cause severe headaches, nausea, vomiting, and confusion.
Headaches that are chronic
Seizures
Children with developmental delays or learning difficulties
Tremors or involuntary movements
Dementia or cognitive decline in adults
Physical or emotional stress, exercise, fever, coughing, or straining may trigger or worsen the symptoms of moyamoya disease.
During a moyamoya disease diagnosis, the doctor will review the patient's medical and family history, perform a physical examination, and perform some tests to determine the blood flow and structure of the brain. These tests may include:
A magnetic resonance imaging (MRI) scan creates detailed images of the brain and blood vessels by using magnetic fields and radio waves. Symptoms of moyamoya disease include narrowing or blocking of the carotid artery, as well as the development of small blood vessels at the brain base.
Computerized tomography scan (CT scan): This test uses X-rays to create cross-sectional images of the brain. It can detect stroke or bleeding, but it may not detect moyamoya disease at its earliest stages.
Through an X-ray imaging, a thin tube called a catheter is inserted into a blood vessel in the groin and guided to the brain. The blood vessels of the brain are highlighted by injecting dye through the catheter. During this test, a blood vessel narrowing or blockage can be detected as well as collateral blood vessels that form as a result of moyamoya disease.
Transcranial Doppler ultrasound measures the blood flow rate and direction in the blood vessels of the brain. It can show reduced blood flow in the carotid artery and increased blood flow in collaterals.
The metabolic activity and blood flow of the brain are measured using positron emission tomography (PET) and single-photon emission computerized tomography (SPECT) using a small amount of radioactive substance. Using these images, you can determine which parts of the brain are affected by moyamoya disease and how much damage has been done.
The electroencephalogram (EEG) measures the electrical activity in the brain using electrodes attached to the scalp. Abnormal brain waves can indicate seizures or other neurological problems.
Treatment options for moyamoya disease include restoring blood flow to the brain, preventing or reducing the risk of stroke, and managing symptoms.
To prevent or treat stroke, certain medications may be prescribed, such as aspirin, a blood thinner that prevents blood clots, or amlodipine, a calcium channel blocker that lowers blood pressure and improves blood flow. In addition to diazepam, an anti-seizure medication that reduces anxiety and muscle spasms, other medications may be prescribed to control seizures.
Revascularization is the main surgical option for moyamoya disease as it bypasses blocked or narrowed blood vessels and creates new pathways for blood to flow to the brain. As a result of revascularization surgery, a healthy artery from the scalp is connected to a brain artery by direct bypass, while indirect bypass stimulates the growth of new blood vessels by placing a piece of muscle, fat, or blood vessel on the brain surface. For most people with moyamoya disease, surgery can improve symptoms and reduce stroke or bleeding risks, but not for everyone. As another surgical option for moyamoya disease, brain surgery may be performed to remove or repair a ruptured aneurysm, which is a bulge or weakness in a blood vessel that can leak or burst and cause bleeding in the brain.
A person may be recommended some therapies to help them recover from the effects of a stroke or bleeding, including physical therapy, which can help them regain lost mobility and physical function, or speech and language therapy, which can help them improve their ability to communicate and swallow. Behavioral therapy, for example, can help cope with stress, anxiety, and depression as well as address the emotional and psychological aspects of moyamoya disease.
Moyamoya disease has no specific preventive measure, but lifestyle changes and regular check-ups may help reduce complications and improve quality of life. Some preventive measures may include:
Smoking and excessive alcohol consumption can damage blood vessels and increase the risk of strokes or bleeding
Obesity and diabetes can be prevented by maintaining a healthy weight and eating a balanced diet
Keeping a moderate and regular exercise schedule can improve blood circulation and cardiovascular health, but avoiding vigorous or strenuous activities that can worsen symptoms
Meditation, yoga, and breathing exercises can calm the nervous system and reduce the effects of emotional stress by managing stress and practicing relaxation techniques
Following the doctor's instructions and taking medications as prescribed can prevent or treat strokes, seizures, and other complications
When symptoms of stroke or bleeding occur, such as sudden weakness, numbness, vision problems, headaches, or confusion, seeking medical attention immediately can save lives and prevent permanent damage.
Regular follow-up visits and tests with the doctor can monitor the condition and treatment effectiveness
