Moyamoya Disease: Treatment, Procedure, Cost and Side Effects

Moyamoya Disease is also known as moya moya syndrome or moyamoya syndrome.

Drugs such as antiplatelet agents (including aspirin) are usually given to prevent clots, but surgery is usually recommended. Since moyamoya tends to affect only the internal carotid artery and nearby sections of the adjacent anterior and middle cerebral arteries, surgeons can direct other arteries, such as the external carotid artery or the superficial temporal artery to replace its circulation. The arteries are either sewn directly into the brain circulation, or placed on the surface of the brain to reestablish new circulation after a few weeks. Moyamoya disease is categorised as an idiopathic disease that has a progressive nature which leads to recurrent strokes due to occlusion of the terminal internal carotid arteries. Revascularization surgery for symptomatic MMD is considered the standard treatment for preventing further stroke. The main objective of surgery is to augment intracranial blood flow using an external carotid system by either direct bypass or pial synangiosis. Although this phenomenon is a natural adaption process for compensating for stenosis of the internal carotid artery (ICA), it can be achieved readily by either extracranial-intracranial bypass or vasculogenesis using indirect pial synangiosis for symptomatic patients. Treatment measures include aspirin which helps prevent the development of small blood clots developing within the narrowed vessels, anti-seizure medications which is used to stop the patient’s seizure disorder and calcium channel blockers which may improve symptoms of headache and in some patients reduce symptoms related to transient ischemic attacks. In rare instances, anticoagulants such as lovenox or coumadin are administered in very unstable patients having frequent symptoms, but because of the obvious risk of cerebral bleeding in this condition, they are rarely indicated as long-term measures. There is no medication available which will stop the progression of the cerebral artery narrowing, however, and the disease will continue to progress in the vast majority of patients regardless of treatment.

The surgical procedures are designed to help re-establish the blood supply to the brain by diverting the scalp blood supply to the brain surface and in that way bypass the progressive loss of brain hemisphere blood flow. Over the years there have been many surgical procedures proposed to treat moyamoya, and they have been divided as “indirect” and “direct” operations. The indirect procedures are usually carried out in children and patients of the younger demographic, include pial synangiosis, encephalomyosynangiosis (EMS), encephaloduroarteriosynangiosis (EDAS), dural inversion, and other similar variants. These operations involve the placement of what is called vascularized structures from the scalp and/or the membranes that surround the brain onto the brain surface, which in most moyamoya patients will induce the growth of new blood vessels into the brain. The most common direct procedure involves the direct suturing of a scalp blood vessel, the superficial temporal artery, to a middle cerebral artery branch on the brain surface. Long-term results following surgery of either type have been quite good, with long-term prevention of strokes seen in published series of both pediatric and adult patients. All of these operations have in common the concept of a blood and oxygen "starved" brain reaching out to grasp and develop new and more efficient means of bringing blood to the brain and bypassing the areas of blockage. The modified direct anastomosis and encephalo-myo-arterio-synangiosis play a role in this improvement by increasing cerebral blood flow (CBF) after the operation. A significant correlation is found between the postoperative effect and the stages of preoperative angiograms. It is crucial for surgery that the anesthesiologist have experience in managing children being treated for moyamoya, as the type of anesthesia they require is very different from the standard anesthetic children get for almost any other type of neurosurgical procedure.

Patient’s who are experiencing stroke-like symptoms, are advised to consult a neurosurgeon. The surgeon will examine and try to gain as much knowledge as possible about the symptoms, current and previous medical problems, current medications, and family history. They will perform a physical exams. Doctors can usually make a diagnosis of moyamoya using MRI machines if the images show 1) diminished blood flow in the internal carotid artery and the middle and anterior cerebral arteries and 2) prominent collateral blood flow at the base of the brain. To confirm the diagnosis of moyamoya disease, an angiogram is typically required.

Patients need to talk to their doctors and give them their full medical history as well as a list of all the medications they are on. The treatment can only be started after the patients have undergone a few tests and come out with positive results. Since this treatment involves the brain, numerous tests have to be taken to ensure that the patient's life will not be at risk and there will not be any complications during the procedure. The doctor will review thesymptoms and the patient's medical history. The doctor will perform a physical examination followed by several tests to diagnose moyamoya disease and any underlying conditions.

There are no particular side effects to the treatment. Since the brain is involved in the treatment the side effects only will be a slow recovery.

If a patient who is treated surgically preceding a disabling stroke, even if the condition is severe, the diagnosis tends to be excellent. Even in patients who don’t show any symptoms, surgical treatment has been reported to prevent against strokes. Although, if left untreated, the disease will progress, leading to clinical deterioration and potentially irreversible neurological deficits over time. For patients who have long-term damage from strokes, treatment will also focus on physical therapy, speech therapy, and occupational therapy to help them regain function and cope with any remaining disability.

The diagnosis for patients with moyamoya is very hard to predict because the disease’s history is not well known. Moyamoya can progress either very slowly with occasional TIAs or strokes, or it can cause rapid decline. The overall diagnosis for patients with moyamoya disease depends on how fast vascular blockage occurs, and to what extent. Diagnosis also is determined by the patient’s ability to develop effective collateral circulation, the age at onset of symptoms, and the severity of disability resulting from a stroke. The patient’s neurologic condition at the time of treatment is more important in determining long-term outcome than the patient’s age.

The price depends on how sever the disease is or at what stage has it reached. The usual doctor’s consultation fee is around Rs. 500 to Rs. 1,000. After the diagnose is done the treatment price can range from Rs. 1500 to 5000.

The treatment results are usually permanent.