There is still disagreement between conservative medical treatment and aggressive interventional embolization or surgical treatment for unruptured intracranial aneurysms. The results of the largest international multicenter study published recently may give us some insight. 1. Risk factors affecting bleeding The results of the International Study of Unruptured Intracranial Aneurysms, the largest multicenter study in the world, were reported in a phase I retrospective for patients with asymptomatic aneurysms without a history of subarachnoid hemorrhage, the annual rupture rate was 0.05% for aneurysms less than 10 mm in diameter, and 0.05% for aneurysms 10 to 25 mm and greater than 25 mm in diameter, respectively. The results of the phase II prospective study, in which 4060 people from more than 60 treatment centers in the United States, Canada, and Europe were studied and observed for more than 7 years, were divided into the untreated group, the group that underwent microsurgery, and the group that underwent interventional treatment. The results showed that the total annual incidence of ruptured bleeding from unruptured intracranial aneurysms was approximately 1.9%. Further analysis showed that the size, location, and regularity of the shape of the aneurysm, the presence of a family history, whether it was multiple, and the recent growth rate were all factors influencing whether the aneurysm would bleed. In addition, advanced age, high blood pressure, smoking, and female patients are all aneurysms prone to rupture. The International Study Group on Unruptured Intracranial Aneurysms published information on the natural history and prospective surgery-related disability and death rates of 2621 patients with unruptured intracranial aneurysms, and the results showed that the risks of surgical treatment for some patients should not be ignored. For example, age is an important factor in patient outcomes, and while the disability and death rate is 6.5% for patients <45 years of age, it is 32% for patients >64 years of age; the disability rate is <3% for aneurysms ≤5 mm, while the mortality and disability rate for giant aneurysms is about 20%; and the surgical outcome for posterior circulation aneurysms is worse than for anterior circulation aneurysms, with a mortality rate of 9.6% and a disability rate of 37.9% for giant posterior circulation aneurysms. The mortality rate of posterior circulation giant aneurysm is 9.6% and the disability rate is 37.9%. In addition, the doctor's surgical experience also obviously affects the treatment results. 3.The initial advantage of embolization treatment showed that the relative risk was reduced by 22.3% in the group with unruptured bleeding and 29.7% in the group with ruptured bleeding by embolization. This is a preliminary indication that endovascular embolization is superior to craniotomy and significantly reduces the immediate postoperative disability and mortality of patients. It can be seen that the results of the above two international multicenter studies are more supportive of embolization therapy, and most scholars believe that the advantages of endovascular embolization therapy for unruptured intracranial aneurysms are more obvious if the patient is older than 65 years old or if the patient has other diseases, and it is believed that with the continuous improvement of new materials and techniques for embolization, the interventional treatment for individual patients with unruptured intracranial aneurysms will be further improved. The "risk-benefit ratio". However, experts also point out that, compared with open surgery, embolization treatment of intracranial aneurysms may have the deficiencies of low complete embolization rate, higher rebleeding rate and recanalization rate after embolization, and its long-term efficacy also needs further follow-up studies. 4.How to choose the treatment strategy Observation, medical adjuvant therapy, microsurgical clamping and endovascular embolization are the four countermeasures for unruptured intracranial aneurysm, and it is still controversial whether unruptured intracranial aneurysm should be treated conservatively or aggressively, and the more consistent view is to weigh the "risk-benefit ratio" by individualized analysis of a large number of influencing factors. The consensus is to weigh the "risk-benefit ratio" against a large number of influencing factors on an individual basis. (1) Small incidental intracranial cavernous sinus aneurysms do not require treatment; large symptomatic intracranial cavernous sinus aneurysms should be treated aggressively if age permits and if symptoms are severe or progressing. (2) All intracranial symptomatic aneurysms should be considered for management; if they are acute, they should be treated urgently; for large and massive symptomatic aneurysms, the surgical risk is high and management should be centralized and individualized. (3) Aneurysms with a history of subarachnoid hemorrhage should be managed regardless of size, especially if they are located on top of the basilar artery; the patient's age, health status, and risk of treatment may affect the management of the aneurysm and should be closely monitored when treated conservatively. (4) Asymptomatic aneurysms without a history of subarachnoid hemorrhage should be observed unless the patient is young, has a daughter aneurysm, or has other unique hemodynamic features that warrant consideration of treatment; a family history of subarachnoid hemorrhage should also be considered for aggressive management. (5) Aneurysms larger than 10 mm should be treated aggressively, taking into account age, health status, and risk of aneurysm rupture.