The prevalence of intracranial aneurysms is 3%, and is higher in those with a family history or autosomal dominant polycystic kidneys. Aneurysms can be treated surgically or endovascularly, with endovascular therapy being increasingly used. Risk factors for aneurysm rupture include increase in aneurysm diameter, location, and decortication characteristics. Screening for aneurysms is generally recommended for high-risk groups (at least two first-degree relatives with aneurysms or patients with autosomal dominant polycystic kidneys); other groups (one first-degree relative with an aneurysm) may be considered after evaluating the benefits and risks. The choice between continued observation and aggressive treatment of an aneurysm depends on the characteristics of the patient, the characteristics of the aneurysm, and the experience of the physician. Risk factors for aneurysm development: Age, sex and family history are important non-interventional risk factors. Patients with a family history of aneurysms have a higher risk of aneurysm enlargement and rupture than those without a family history; smoking, moderate to heavy alcohol consumption, and high blood pressure are important interventional risk factors for aneurysm progression. When to screen and re-screen: Screening is not recommended for children and adolescents under 20 years of age, except in unusual circumstances; the prevalence of aneurysms increases with age, and the absence of an aneurysm at one screening does not mean that an aneurysm will not occur thereafter, and screening is recommended every 5 years. Screening methods: Although digital subtraction angiography is the gold standard for aneurysm diagnosis, CT angiography and MRI angiography are non-invasive examinations, which are more reasonable as screening methods. CT angiography has a sensitivity rate of 100% for aneurysms with a diameter of more than 10 mm, 93% for those with a diameter of 4-9 mm, and 61% for those with a diameter of less than 3 mm; MRI angiography has a slightly lower sensitivity rate. The sensitivity rate of MRI angiography is slightly lower. Risk factors for aneurysm rupture: the larger the size of the aneurysm, the higher the risk of rupture. The 5-year risk of rupture of aneurysms with a diameter of less than 6mm is almost zero, the 5-year risk of rupture of aneurysms with a diameter of 7-12mm is 2.6%, the 5-year risk of rupture of aneurysms with a diameter of 13-24mm is 14.5%, and the 5-year risk of rupture of aneurysms with a diameter of more than 25mm is 40%.