Characteristics of AVMs Cerebral arteriovenous malformations are congenital disorders in which the main health threats are hemorrhage, seizures, blood theft and headaches. A significant proportion of patients are accidentally found to have intracranial cerebral AVMs during examination for other reasons; therefore they can be classified as symptomatic and asymptomatic cerebral AVMs. pathogenicity of large AVMs Most asymptomatic AVMs can often coexist with the patient for a lifetime without threat of damage, or until a bleeding from a malformed cerebral lesion and an induced seizure occur and the patient is seen. That is why we call AVMs at risk for hemorrhage or seizures high-risk arteriovenous malformations. Since high-risk AVMs are life-threatening to patients, when a brain AVM is found by chance, it should be recommended to have a whole-brain angiography as soon as possible and be judged by meticulous imaging analysis. For AVMs without high-risk factors, they can be recommended to have regular review and avoid overexertion; especially for giant brain AVMs, if there are no obvious symptoms, they may accompany the patients to spend their lives relatively peacefully. In our group, there are 4 cases of giant AVM, after having done partial embolization one to eliminate the symptoms of blood theft, the follow-up is 14-17 years, and the life and work are basically normal. Risk analysis of high-risk AVM More than 200 cases of AVM in our group and reported in the literature, the usual high-risk factors consist of the following reasons: the presence of AVM intrafocal, prefocal, or parafocal aneurysms, as well as narrow deep venous drainage or intracerebroventricular growth of AVM, especially malformed reflux hyperobstructive features; these are the main causes of highly susceptible to intracranial focal hemorrhage. Of course, for AVMs that develop from cerebral hemorrhage and epilepsy, it is necessary to treat them carefully with the aim of eliminating aneurysms and other major high-risk factors, and for small AVMs to eliminate the lesion as completely as possible while embolizing it; for Avm with deep penetrating arterial supply or difficult to embolize completely, the aneurysm can be treated first and the blood flow in the main blood supply area of the malformation can be slowed down as much as possible, one is to reduce flow and pressure within the AVM, but rather to create better healing conditions for gamma knife treatment. The need for individualized embolization is possible regardless of the size of the AVM with high risk factors. In large AVMs, an overemphasis on reducing or eliminating the volume of the malformation after eliminating high-risk factors often requires greater risk to the patient; because an oversized malformation lesion can involve many functional brain areas while creating an abnormal distribution balance to local cerebral perfusion blood flow. After embolization or surgical removal of larger AVM lesions, the chance of brain tissue damage in functional areas and generation of abnormal cerebral overperfusion increases significantly, which will instead cause greater suffering to patients. If patients are allowed to adjust factors such as systemic blood pressure and lifestyle habits to coexist with AVM lesions without clear high-risk factors, they can instead maintain a relatively good quality of survival. However, for small AVM, after all, it is an abnormal pathological structure, and while embolization eliminates risk factors, complete occlusion of the lesion should be strived for as soon as possible; if elimination of the entire lesion may damage the brain tissue in the functional area, the feasibility of combined endovascular and gamma knife treatment needs to be reasonably evaluated to maximize the chance of benefit for the patient. Indications for gamma knife on AVM Gamma knife treatment of cerebral AVM has been or has had a positive effect; however, because the damage of gamma radiation on abnormal blood vessels is mainly the elastic fiber layer of blood vessels, followed by endothelial structures. Therefore, the therapeutic effect on venous structures is not clear, and it is also worth noting that after irradiation of aneurysmal structures, not only the aneurysm cannot be occluded, but also the damage to the elastic fiber is very likely to induce rupture and bleeding of the aneurysm. In this group, there are AVM containing focal aneurysm structures reviewed after 2 years of gamma knife treatment, the malformation foci disappeared, but the focal aneurysm did not bleed but the morphology did not change. AVM combined with gamma knife safety and effective neurointerventional endovascular treatment of AVM cases, the first principle to follow should be safety and effectiveness. The nervous system has a complex function that no other organ has, and any inappropriate treatment may bring temporary or lifelong disability or even end of life to the patient. This requires us to pay more attention to the quality of survival after treatment while eliminating the risk factors of the lesion when formulating the strategy for the treatment of cerebral AVM. If there is no absolute certainty of embolization treatment of the malformed lesion in the functional brain area, it should be appropriate, and after eliminating the most important factors such as aneurysm, the residual lesion should be transferred to gamma knife treatment with longer healing time but less relative ischemic damage; or in small asymptomatic Or in small asymptomatic AVMs or AVMs without high-risk factors, direct Gamma Knife treatment with a higher safety factor, finally completing treatment consistent with individualized comprehensive treatment of cerebral AVM, which may be a safer and more effective way to treat AVMs at present.