Second, brain AVM stereotactic radiosurgery treatment is the use of modern stereotactic technology and computer functions, the high dose of high-energy proton beam from multiple angles and directions at once gathered on the target tissue to achieve the purpose of destroying the target point to treat the disease. At present, the most used is gamma knife, whose therapeutic effect on AVM comes from radiation-induced endothelial proliferation of malformed vessels, structural destruction of the vessel wall gradually replaced by collagenous material, and finally thickening and stiffening of the vessel wall, progressive luminal narrowing and consequent slowing of blood flow, which eventually leads to thrombosis and AVM occlusion. Xiong Hui, Department of Neurosurgery, Affiliated Hospital of Shandong University of Traditional Chinese Medicine The efficacy is closely related to the following factors: (1) The rate of complete occlusion rises accordingly with the extension of the follow-up period, so an observation period of 2 or 3 years should be given in assessing the effect of gamma knife treatment for AVM. However, there is also a potential risk of bleeding during this period. (2) Most scholars believe that the peripheral dose is the decisive factor affecting the rate of complete occlusion of AVM. 20-25 Gy is a more reasonable peripheral dose for the treatment of AVM. (3) As the volume of AVM increases, the rate of complete occlusion gradually decreases. lunsford et al. reported the occlusion of 272 cases of AVM after 2 years of gamma knife treatment, the total occlusion rate of lesion volume <1 ml was 100%, 1-4 ml was 85%, 4-10 ml was 58%. The authors observed that the complete occlusion rate of 52 AVM cases was 56.9%, of which the complete occlusion rate of volume <4 ml was 69.2%, the complete occlusion rate of 4-10 ml was 60%, and the complete occlusion rate of >10 ml was 38.5%. Therefore, AVM with volume <10 ml is suitable for gamma knife treatment, and AVM larger than l0 ml can be treated with endovascular interventional embolization to reduce its volume before gamma knife treatment. It is generally considered that AVMs with a maximum diameter of less than 3 cm, small lesions located in important functional areas or deep brain, those whose systemic condition cannot tolerate craniotomy, and residual lesions after surgical resection or endovascular interventional embolization are indications for this treatment. Comprehensive domestic and foreign literature reports, the rate of complete occlusion of AVM with indications for gamma knife treatment can reach 56.9% to 91%, with an average of 78.7%, including lesion reduction, the efficiency is above 90%. However, for diffuse cerebral AVM, the therapeutic effect of stereotactic radiosurgery is limited, and general conventional radiotherapy can reduce the symptoms of blood theft.