Brain arteriovenous malformation (BAVM), also known as cerebrovascular malformation, is a dangerous congenital cerebrovascular disorder that occurs when the embryo is 45-60 days old and there is no normal capillary network between the arteries and veins, but only an abnormal mass of malformed vessels. Clinicians grade AVMs according to the size, location and depth of the artery supplying the blood, the size of the malformed mass, and the depth of the draining veins. The lower the grade, the better it is to treat; the higher the grade, the more difficult it is to treat. AVM is usually diagnosed in the following cases: 1. Sudden severe headache during exercise or emotional excitement, often accompanied by vomiting, mental clarity may be awake or blurred or even comatose, numbness or weakness of the arms and legs, and in severe cases, neurological dysfunction such as hemiparesis and inability to speak. Most of the time, the onset of the disease is in adolescence. 80%-90% of patients with the first bleeding of AVM can survive. 2. convulsions, also known as seizures. About more than half of the AVMs have seizures. 3. Headache. More than half of the patients have a history of headache. The headache is often on one side and may resolve on its own. 4. Gradually increasing neurological impairment. When these conditions occur, the doctor will recommend that the patient undergo CT, magnetic resonance imaging (MRI), and cerebral angiography (DSA) to confirm the diagnosis. In terms of treatment, there are three types of treatments: 1) craniotomy, 2) endovascular embolization, which is also known as interventional therapy, in which the malformation is fully or partially occluded by injecting ONYX and other gums into the malformation (which has developed rapidly in recent years), and 3) stereotactic radiosurgery, which is also known as gamma knife and radio-wave knife. These methods can also be applied in combination, that is, combined treatment, usually with better results.