An intracranial aneurysm is the equivalent of an untimely bomb in the skull. It is untimely because there is no telling when it will break, but once it ruptures, the death or disability rate is extremely high. There is no way to prevent the occurrence of intracranial aneurysms, and most patients are diagnosed with intracranial aneurysms only when they have brain hemorrhage. In recent years, many health screening units have included magnetic resonance imaging (MRA) as a routine screening treatment item, increasing the diagnosis rate of unruptured aneurysms. So how should ruptured or unruptured aneurysms be treated, and how should treatment options be chosen? What is a cerebral aneurysm? An intracranial aneurysm is not a tumor, but a localized bulge in the wall of an intracranial blood vessel, just like a bicycle tire that bulges out locally before it bursts, and the wall of this bulge will be very thin. Clinically, aneurysm patients also often have aneurysm rupture when they are emotionally excited, forceful and other blood pressure fluctuations, and some patients bleed when they are calm, often with severe headache as the prominent manifestation, and the patient describes the pain as cracking or exploding. Once an intracranial aneurysm ruptures and bleeds, the death and disability rates are extremely high, with 10%-15% of patients dying suddenly before they can seek medical attention, and the death rate for the first bleed is as high as 35% and for the second bleed 60%-80%. Patients with suspected aneurysm of brain hemorrhage should be examined as early as possible and treated for the aneurysm as soon as possible. Of course, aneurysms are also benign diseases, and if diagnosed in time and treated with modern neurointerventional or surgical procedures, patients can be cured for life after surgery. What are the symptoms of aneurysm patients? Intracranial aneurysms that do not rupture usually do not cause any clinical symptoms, with a few symptoms such as headache and droopy eyelids, which causes many patients to visit the hospital only after the aneurysm ruptures and bleeds. Once an aneurysm ruptures and bleeds it often presents with a severe headache, along with frequent vomiting, profuse sweating, body temperature may rise, and neck stiffness. There may also be impaired consciousness and coma, and some patients may even die suddenly before they can get medical attention. What is the incidence of aneurysms? The prevalence of intracranial aneurysms in the population ranges from 2% to 7% and can occur at any age, with a common occurrence between the ages of 40 and 60, but there are significant geographic and racial differences in their incidence. Studies have shown that the prevalence of intracranial aneurysms in the Asian population is 2.5%-3.0%, but the majority of patients remain asymptomatic throughout their lives, and about 0.5%-3.0% will rupture and bleed, which can have serious consequences if they do. Are aneurysms congenital? Do I need to check for aneurysms in my brain during my regular physical exam? Aneurysms are usually not congenital and most aneurysms do not appear until the age of forty. It is controversial whether to screen for intracranial aneurysms in a healthy population. The Chinese expert consensus is that MRA or CTA is feasible to rule out intracranial aneurysms in people with a family history or genetic disorders associated with aneurysm development, such as polycystic liver, polycystic kidney or Marfan syndrome, especially in women, age >30 years, smoking or with hypertensive disease. (DSA) is required to confirm the diagnosis. How is an aneurysm diagnosed? A ruptured cerebral aneurysm causing subarachnoid hemorrhage can cause severe headache, coma and other typical symptoms, which can be confirmed by immediate cerebral angiography. It is difficult to diagnose cerebral aneurysm without any symptoms before it ruptures because patients usually do not go to the hospital for these special tests without any physical discomfort. For those who have the following symptoms, they should be alert: drooping upper eyelid on one side without other symptoms or triggers; sudden onset of headache on one side with pulsating pain located around the orbit; visual field loss on one side, etc. When any of the above symptoms occur, be sure to go to a hospital in a condition to have a CT or MRI examination and, if necessary, a cerebral angiogram (DSA). What conditions can cause an aneurysm to rupture? At present, we are not sure why or when an aneurysm will rupture, but it is generally believed that the following conditions may increase the risk of aneurysm rupture: First, high blood pressure, weight bearing or constipation when going to the toilet, can raise the pressure in the brain, which can lead to aneurysm rupture and bleeding. The second is emotional stress, when there is a lot of joy or anger, which can lead to an increase in cerebral blood pressure, which can lead to a ruptured aneurysm. We often encounter patients arguing with others before aneurysm rupture, or even some patients when playing mahjong hokum. The third is oral anticoagulant drugs, such as warfarin. What kind of aneurysm is prone to rupture? Many factors determine how likely an aneurysm is to rupture, such as the size, shape and location of the aneurysm, as well as the clinical symptoms caused by the aneurysm. International studies have concluded that for aneurysms >7mm in diameter, the risk of bleeding is significantly increased. Studies in Asian populations have concluded that the risk of aneurysm rupture is greatly increased for aneurysms >5 mm in diameter. For irregularly shaped aneurysms, the risk of rupture is significantly higher than for regularly shaped aneurysms. Once an aneurysm has ruptured, it is prone to re-rupture; therefore, the sooner it is treated, the better. Should an unruptured aneurysm be treated aggressively? The management of unruptured aneurysms is still one of the controversial topics both nationally and internationally. For asymptomatic unruptured aneurysms, the size of the aneurysm mentioned by Prof. Shih is an important deciding factor, and treatment is generally recommended for aneurysms with a diameter of 5mm or more. For aneurysms less than 5mm in diameter, a variety of other factors should be considered, including the location and shape of the aneurysm, to fully assess the risk of aneurysm rupture. For some patients who know they have an aneurysm and are under more psychological stress, which seriously affects their normal work life, a more aggressive treatment approach can be taken. Aneurysms treated conservatively should be followed up with long-term review. For unruptured aneurysms with symptoms, all should be treated actively, which has been agreed at home and abroad. Regardless of the size of the aneurysm, any aneurysm that causes associated neurological symptoms and signs should be treated aggressively surgically. Because the appearance of these symptoms may be associated with the rapid increase of aneurysm size or a small amount of blood leakage, which indicates a high possibility of aneurysm rupture and bleeding. Therefore, symptomatic intracranial aneurysms are an absolute indication for treatment and should be treated as soon as possible to avoid delays that could lead to fatal and extensive bleeding. Studies have shown that 10%-43% of patients may develop a warning headache prior to a cerebral hemorrhage, and that patients who develop such a headache are ten times more likely to have a recent rebleed, which occurs mostly 2-8 weeks before an apparent cerebral hemorrhage.