Moyamoya disease, also known as spontaneous basilar artery occlusion or abnormal cerebral vascular network, is a chronic cerebrovascular disease with unknown etiology. It is characterized by slow thickening of the intima at the end of the internal carotid artery and the beginning of the anterior cerebral artery and middle cerebral artery, gradual narrowing of the arterial lumen to occlusion, and compensatory dilation of the cerebral basilar perforating artery. Due to stenosis or occlusion of the intracranial starting segment of the internal carotid artery, an abnormal vascular network appears at the bottom of the brain, which resembles "smoke" in cerebral angiography, hence the name "smoke disease". This name was first used in Japan in the 1960s and has since been applied in other parts of the world. In 1969, Japanese scholars Suzuki and Takaku officially named this disease "smog disease".
2、 The etiology of Moyamoya disease is not yet clear and may be related to various factors such as genetics, infection, and immunity. Among them, genetic factors play an important role in the onset of smoke disease, with about 10% of smoke disease patients having a family history. In addition, certain infectious factors may also lead to the onset of smoke disease, such as viral infections.
3、 Symptoms of Moyamoya Disease
Transient Ischemic Attack (TIA) type Moyamoya disease is the most common type, accounting for 70% of all idiopathic Moyamoya diseases. Patients may repeatedly experience transient paralysis or weakness, often resulting in hemiplegia, as well as alternating left and right hemiplegia or bilateral hemiplegia. After the attack, the motor function will be fully restored, and the course of the disease is usually benign, with a tendency for spontaneous relief or complete cessation of the attack. However, a very small number of cases are accompanied by seizures, headaches, or migraines. This type is also rare for transient sensory disorders, involuntary movements, or intellectual disabilities.
Cerebral infarction type smoking disease can lead to acute stroke, resulting in persistent paralysis, aphasia, visual impairment, and intellectual disability.
Epilepsy type smoking disease frequently presents with epileptic seizures, partial seizures, or status epilepticus, accompanied by epileptic discharges in the electroencephalogram.
In addition to TIA type, there are also non TIA type smoke diseases, including infarct type, epilepsy type, and hemorrhagic type. These types of diseases have complex and variable course, and poor prognosis. For example, mixed types such as epilepsy with infarction, epilepsy with TIA, etc. may occur. If it is only a simple epileptic seizure, the prognosis may not be very poor. Among all types, patients with onset before the age of 4 have a poor prognosis. In addition, the severity of clinical symptoms depends on the compensatory effect of collateral circulation. If sufficient cerebral blood flow can be maintained, clinical symptoms may not occur, or only transient TIA attacks or headaches may occur. If cerebral blood flow cannot be maintained, the symptoms will be severe and may lead to extensive brain damage.
4、 Diagnosis and Treatment of Moyamoya Disease
Diagnosis: The classic criteria for Moyamoya disease mainly refer to bilateral lesions, including occlusion of the intracranial segments of the bilateral internal carotid arteries. In addition, another significant feature of this disease is the presence of many smoke like neovascularization in the skull base. This type of neovascularization is formed by the brain to compensate for insufficient blood supply, and they entangle and entangle together, giving people the impression of "smoke". The diagnostic criteria for Moyamoya disease are mainly based on this typical bilateral lesion type.
However, Moyamoya disease does not always manifest as classic bilateral lesions. Sometimes, the lesion may only appear on one side, such as occlusion of the intracranial segment of one internal carotid artery, while the other internal carotid artery may be completely normal. This type is sometimes referred to as unilateral smoking disease and is a variant of smoking disease. Although this situation is relatively rare, it still requires the vigilance and accurate diagnosis of doctors to ensure that patients receive the correct treatment.
It is worth noting that whether it is bilateral or unilateral lesions, Moyamoya disease can have a significant impact on the health and quality of life of patients. Due to the disruption of blood supply to the brain, patients may experience a range of symptoms, including headaches, dizziness, nausea, vomiting, and more. If the condition is severe, neurological dysfunction such as hemiplegia, aphasia, and epilepsy may also occur. Therefore, once diagnosed with Moyamoya disease, whether it is bilateral or unilateral lesions, timely treatment is needed.
Treatment: Currently, there is no direct cure and the occluded internal carotid artery cannot be simply opened through surgery.
However, surgery can serve as an effective indirect treatment method. The purpose of surgery is to establish new blood flow channels, allowing intracranial and extracranial arteries to communicate and increase blood flow supply to the brain. This can be achieved through various surgical methods, including bridging, patching, and flipping of the dura mater.
Bridge surgery is the process of connecting healthy blood vessels to diseased blood vessels to establish a completely new blood flow channel. This can allow blood to flow from extracranial to intracranial, increasing the blood supply to the brain.
Patch surgery refers to indirect vascular bypass surgery, which involves applying some highly regenerative blood vessels to the surface of the brain to regenerate new blood vessels, in order to improve the condition of ischemia.
The dura mater flipping surgery involves flipping the dura mater over to establish a completely new blood flow channel. This can allow blood to flow from extracranial to intracranial, increasing the blood supply to the brain.
5、 How to prevent the occurrence of smoke disease?
Control blood pressure: Hypertension is one of the important factors leading to smoke sickness, so controlling blood pressure is an important measure to prevent smoke sickness. It is recommended to regularly check blood pressure and take antihypertensive medication according to the doctor's advice.
Regular physical examinations: Regular physical examinations can help us detect and treat potential diseases in a timely manner, including smoking related illnesses. It is recommended to undergo a physical examination once a year and pay attention to one's own physical condition.
Maintaining mental health: Mental health is also one of the important factors in preventing smoke sickness. It is recommended to maintain a positive and optimistic attitude, and avoid excessive anxiety and tension.
Healthy diet: Maintain a balanced diet and consume more fiber rich foods such as whole grains, vegetables, and fruits. Reduce the intake of high-fat, high sugar, and high salt foods, and avoid excessive frying and processed foods. At the same time, consume foods rich in high-quality protein in moderation, such as fish, lean meat, and beans, to maintain normal bodily functions.
Control blood sugar and blood lipids: High blood sugar and blood lipids are also risk factors for smoking disease. Regularly monitoring blood sugar and lipid levels, adjusting diet and lifestyle habits in a timely manner, can help prevent the occurrence of smoking disease. For people who already suffer from high blood sugar and high blood lipids, treatment should be carried out according to the doctor's guidance, and medication should be taken to maintain normal levels of blood sugar and blood lipids.
Through the above introduction, we have gained a deeper understanding of smog disease. Although Moyamoya disease is a rare cerebrovascular disease, as long as we understand its etiology, symptoms, diagnosis and treatment methods, and preventive measures, we can effectively prevent and control the occurrence of the disease. In daily life, we should develop good lifestyle habits, control blood pressure, undergo regular physical examinations, and maintain mental health to prevent the occurrence of smoke sickness.