In recent years, subarachnoid hemorrhage has become one of the most important brain diseases that threaten people’s health due to various factors such as the accelerated pace of life, environmental factors and the high prevalence of hypertension and diabetes. The incidence of this disease is second only to atherosclerotic cerebral infarction and cerebral hemorrhage, and its most common cause is intracranial aneurysm rupture, with headache being the main symptom at the onset. The disease has a peak incidence between the ages of 50 and 60, with an increase in young and middle-aged patients in recent years. It is also worrisome that subarachnoid hemorrhage has a rapid onset and can be life-threatening if it develops. Especially in young and middle-aged people, it is important to maintain good lifestyle habits and seek early medical attention for sudden headaches and other symptoms. What is subarachnoid hemorrhage? The human meninges are, in order from the outside to the inside, the dura mater, the arachnoid membrane and the soft membrane, and the cavity between the soft membrane and the arachnoid membrane is called the subarachnoid cavity, which is usually filled with cerebrospinal fluid. When blood flows directly into the subarachnoid space after a rupture at the base of the brain or a superficial part of the brain, a subarachnoid hemorrhage is formed, which can be life-threatening once it develops. What causes subarachnoid hemorrhage? According to data, 80% of subarachnoid hemorrhages are caused by ruptured cerebral aneurysms. Cerebral aneurysms are not true tumors, but are usually caused by a lesion in the wall of an intracranial artery that forms a localized balloon-like abnormal expansion. Brain aneurysm tends to increase with age, and the vessel wall becomes thinner and thinner, so it is like an “untimely bomb” under the constant impact of blood flow, and will rupture when it encounters emotional excitement, exertion and force, causing fatal intracranial hemorrhage. In addition, cerebrovascular malformations, hypertensive cerebral atherosclerosis, intracranial tumors, blood disorders, arteritis caused by various infections, and abnormal vascular network of the skull base can also cause the disease. How to grade subarachnoid hemorrhage Currently, the clinical condition of subarachnoid hemorrhage is generally divided into five grades from mild to severe: Grade 1 is mild headache; Grade 2 will have severe headache, partial cerebral nerve palsy, stiff neck, etc.; Grade 3 will have mild drowsiness and confusion; Grade 4 will have coma and hemiparesis; Grade 5 will have deep coma and be in a state of near death. Usually the first three levels are easier to treat, while the fourth and fifth levels are more difficult to treat. Because the disease is mostly caused by ruptured aneurysms, the cure and recovery depend on the amount and location of the bleeding. If the bleeding volume is small, the prognosis can be restored to normal; if the bleeding volume is large, complications such as cerebral vasospasm and hydrocephalus may occur, leaving sequelae. In addition, subarachnoid hemorrhage is prone to rebleeding. Clinical statistics show that the mortality rate of the first occurrence of hemorrhage is 30% to 40%, and if not treated in time, the mortality rate of rebleeding will reach 60%. What are the manifestations of subarachnoid hemorrhage? The onset of subarachnoid hemorrhage is rapid, and 90% of patients have a sudden onset. Headache is a prominent manifestation of subarachnoid hemorrhage. Patients with subarachnoid hemorrhage often have sudden onset during activities, often triggered by mental tension, emotional excitement, overexertion or exertion, etc. At the onset, patients mainly show sudden onset of severe splitting-like headache and dizziness, which can be distributed in the forehead, back of the head or the entire head, and can extend to the neck, shoulders, back, waist and legs, etc. This is due to the sudden rupture of intracranial aneurysms, which causes a large amount of blood to flow into the subarachnoid space and directly stimulates the meninges. This is due to the sudden rupture of intracranial aneurysm, which causes a large amount of blood to flow into the subarachnoid space and directly stimulate the meninges. Some patients also have pale face, cold sweat, nausea and vomiting; more than half of the patients may have different degrees of consciousness impairment, with transient confusion in mild cases, and coma may gradually deepen in severe cases. Some patients will have progressive speech and body dysfunction, while others will only have occipital and neck pain, which can be easily misdiagnosed as upper respiratory flu or rheumatic pain, and should be especially noted. In another 10% of patients, cerebral aneurysms of 20 mm to 25 mm in length may present as an occupying lesion, resulting in blurred vision and drooping eyelids, or as a sign of subarachnoid hemorrhage. What habits can cause subarachnoid hemorrhage People with bad habits such as smoking, alcohol abuse, and the “three highs” of hypertension, hyperlipidemia, and hyperglycemia are prone to sudden subarachnoid hemorrhage. Some studies have shown that smoking is an independent risk factor for subarachnoid hemorrhage, and that those who quit smoking are at lower risk than smokers. Duration of smoking cessation is strongly associated with a decreased risk. In addition, subarachnoid hemorrhage is a common complication of hypertensive disease. The risk of subarachnoid hemorrhage is 15 times higher in hypertensive patients who smoke than in normal individuals who do not smoke and do not have hypertension. Other risk factors that can cause atherosclerosis, such as diabetes and hyperlipidemia, can also increase the incidence of subarachnoid hemorrhage. For patients with suspected subarachnoid hemorrhage, cranial CT examination is preferred if available, and lumbar puncture and cerebrospinal fluid examination are feasible if CT scan cannot confirm the diagnosis. Whole brain angiography is currently the gold standard for the diagnosis of subarachnoid hemorrhage due to aneurysm rupture. CT angiography (CTA) and MR angiography (MRA) are noninvasive methods of cerebral vascular imaging, and 95% to 98% of patients with aneurysms can be detected by CTA. Both tests are also used for screening of patients with a family history of aneurysm or precursors of rupture, follow-up of patients with aneurysms, and patients who cannot tolerate DSA in the acute phase. Why Early Surgery Once a cerebral aneurysm ruptures, the sooner surgery is performed, the better the outcome is generally. This is because 7 days after bleeding is the peak of cerebral vasospasm and the risk of rebleeding. If endovascular interventional embolization or open aneurysm neck clamping or atherectomy can be performed in time during this period depending on the condition, re-rupture of the aneurysm can be avoided and the mortality rate of patients can be greatly reduced. Interventional surgery can reduce the rate of disability and death by more than 7% compared with other surgical treatment methods.