Moyamoya Disease: Causes, Symptoms & Treatment

Moyamoya disease is a disease that affects the vessels of the brain. As a result of the disease, the vessels in the area of the brain spontaneously close. The occlusion occurs over a long period of time due to fibrous remodeling in the area of the base of the brain. Often, the remodeling occurs in the internal carotid artery.

What is moyamoya disease?

Moyamoya disease is most common in Japan. According to current medical findings, the disease results from genetic mutations on the 17th chromosome. In addition to the genetic and thus congenital form of moyamoya disease, there is also an acquired form of the disease. This is seen, for example, in connection with Down syndrome or arteriosclerosis and is also known as Moyamoya syndrome. The name of Moyamoya disease comes from the Japanese language. Here, moyamoya means ‘puff of smoke,’ referring to the tiny collateral vessels that form as a result of stenosis and resemble smoke in shape on angiogram.

Causes

In the majority of cases, the causes of moyamoya disease are genetic mutations. The gene mutation occurs on chromosome 17 at a specific gene locus. The exact prevalence of moyamoya disease is not yet known. Moyamoya disease is fixed from birth in affected individuals and develops throughout life. In this process, the disease progresses slowly but steadily, leading to occlusion of vessels in the brain, which consequently show an appearance like smoke or fog on the angiogram.

Symptoms, complaints, and signs

Moyamoya disease is associated with occlusion of vessels in the brain. The blood vessels initially narrow over a relatively long period of time. The progressive narrowing of the vessels eventually leads to complete occlusion of the arteries. In most cases, the arteria cerebri media and the arteria carotis interna are affected by the pathological changes. As a result of the occluded vessels, increasing anemia develops in the brain of the diseased individuals. Thus, there is a risk of ischemic attacks and strokes. To compensate for the occluded vessels, numerous tiny blood vessels develop. These vessels appear as side-like or smoky formations on imaging. In Europe, Moyamoya disease is relatively rare. It is much more common in Asia, especially in Japan. Moyamoya disease manifests itself particularly frequently in two- to ten-year-old children and between the ages of 30 and 40. As a result of moyamoya disease and the occlusion of cerebral blood vessels, patients are at increased risk of suffering cerebral infarctions and cerebral hemorrhages. As a result, physicians often discover moyamoya disease in the context of such complications.

Diagnosis and disease progression

In most cases, the diagnosis of moyamoya disease does not take place until the disease manifests itself with typical complications. These include, first and foremost, strokes and bleeding in the brain area. This is because in many patients, it is only after such incidents that appropriate examinations are carried out, which finally point to a moyamoya disease. Rather rarely, a diagnosis of moyamoya disease takes place before acute emergencies, such as stroke, occur. Diagnosis of moyamoya disease usually takes place in specialized centers equipped with the necessary technology for imaging brain areas. First, a medical history is taken with the person affected by moyamoya disease, who describes his or her complaints and any complications that may have occurred. The onset of the signs of moyamoya disease is always important. The clinical examination is mainly based on imaging techniques. The focus is on the patient’s brain. In most cases, an MRI scan and angiography are used. Patients are usually given special contrast agents before the imaging examination. This makes it possible to detect the tiny vessels as well as a reduced supply of blood and oxygen in the brain.

Complications

Because moyamoya disease primarily affects the brain, it can have a very negative impact on the life and daily routine of the affected person.As a rule, the patient suffers a stroke at an early stage, which can lead to various irreversible consequential damages. It is not uncommon for patients to suffer from sensory disturbances and paralysis. Various motor and physical abilities of the affected person are restricted as a result, so that the affected person may even be dependent on the help of other people in everyday life. Without treatment, Moyamoya disease can also lead to death. It is not possible to treat moyamoya disease causally. However, the symptoms and complications can be limited with the help of medication. Furthermore, in most cases, those affected are dependent on regular examinations in order to avoid consequential damage. In severe cases, a bypass can also be performed. A healthy diet and a mindful lifestyle have a very positive effect on the disease and can prevent further complications. However, as a rule, the patient’s life expectancy is significantly reduced by moyamoya disease.

When should you see a doctor?

Moyamoya disease is a serious condition that requires immediate medical attention in all cases. Individuals who experience headaches, loss of consciousness, and other unusual symptoms at regular intervals should seek medical advice quickly. The doctor can diagnose any moyamoya syndrome and then initiate treatment immediately. If this is done early, serious complications can often be avoided. If treatment is not initiated, the narrowing of the brain vessels can lead to strokes and other health consequences. At the latest after a stroke or cerebral hemorrhage, a doctor must make a diagnosis. Affected persons must then be treated in a special clinic and closely monitored. Moyamoya disease is treated by neurologists and internists. Since it is a severe disease that is often fatal, sufferers should also seek the care of a therapist. If a recurrence of vascular occlusion is suspected, the appropriate physician should be informed immediately or the nearest hospital should be visited immediately.

Treatment and therapy

Therapy of moyamoya disease is exclusively symptomatic, since treatment of the causes of the disease has not been feasible to date. Above all, it is important to provide drug therapy for people affected by moyamoya disease. In this context, the persons usually take so-called anticoagulants. In addition, encephalomyosynangiosis as well as encephaloduroarteriosynangiosis are suitable therapeutic measures. It is also possible to treat moyamoya disease by means of surgical interventions. In this case, patients receive a neurosurgical bypass during inpatient interventions. This form of therapy has shown relatively good success to date. During the operation, doctors connect the cerebral and temporal arteries. It is also of great importance in the successful symptomatic therapy of moyamoya disease that patients minimize as many personal risk factors as possible in their own lifestyle. This includes, for example, reducing obesity and high blood pressure and giving up smoking. In principle, regular and permanent medical monitoring of patients is required in order to monitor the progression of the disease and, if necessary, to intervene as quickly as possible in a targeted manner using appropriate therapeutic measures.

Outlook and prognosis

Moyamoya disease can be well treated. However, little is known about the long-term course. Cases are known in which no symptoms occur at all. In other cases, strokes and circulatory disturbances of the brain occur. The course of the disease depends on the age at which the symptoms appear and how severe they are. If left untreated, the condition takes an unfavorable course, with severe neurological deficits developing. First and foremost, there is a high risk of stroke, and a stroke can be severely disabling or fatal. The risk of stroke is significantly reduced by direct or indirect bypass, which promotes blood flow in the brain. About 60 percent of all patients are symptom-free after the procedure. Physiotherapy, speech therapy and occupational therapy can additionally improve the prognosis.The neurologist in charge can make a prognosis based on the symptom picture. However, this must be adjusted regularly, especially in the case of repeated circulatory disturbances and other complications. Any concomitant diseases, as they occur especially in severe cerebrovascular malformations, worsen the prognosis. Patients at risk achieve an optimal prognosis with early evaluation and treatment.

Prevention

Moyamoya disease is genetically caused in affected individuals and is thus fixed from birth. For this reason, the disease cannot be prevented causally. However, medical science is researching ways to effectively prevent genetic disorders such as moyamoya disease.

Follow-up

Since moyamoya disease is usually a hereditary disease, there is no complete cure. Therefore, the affected person should see a doctor at the first symptoms and signs of the disease to prevent the occurrence of further complications and discomfort. The sooner a doctor is consulted, the better the further course of the disease usually is. If there is a desire to have children, genetic testing and counseling should be done to prevent the recurrence of the disease in the children. Most patients are dependent on taking various medications for the disease. The patient should always pay attention to a regular intake and also to a correct dosage of the medicines. In case of questions or uncertainties, a doctor should always be consulted first. In general, attention should also be paid to a healthy lifestyle, whereby excess weight should be avoided. The patient should also avoid alcohol and smoking. Possibly thereby the Moyamoya disease reduces the life expectancy of the patient.

This is what you can do yourself

So far, moyamoya disease can only be treated symptomatically. Drug therapy can be supported by those affected by a number of measures. Individual symptoms such as obesity and hypertension can be alleviated by lifestyle changes. In principle, patients should maintain a healthy lifestyle and ensure a balanced diet. If, at the same time, regular exercise is taken, the typical symptoms can already be greatly reduced. Stimulants such as cigarettes, alcohol and coffee should be avoided. Since the disease exists from birth, a diagnosis can be made at an early stage. Parents who notice the characteristic symptoms in their child should consult a doctor. On the one hand, early diagnosis and treatment improves treatment options. For another, possible risk factors can be ruled out from the outset. Nevertheless, moyamoya patients require permanent medical supervision. Since the disease is a great burden for all involved, an accompanying therapy for the parents and for the affected child is always recommended. After surgery, the patient primarily needs bed warmth and rest. In addition, further visits to the doctor are indicated, during which the patient’s state of health can be checked and any complications detected at an early stage.