Case 1: Hou, female, 27 years old, had a sudden onset of headache with persistent dull pain, nausea and vomiting with weakness of the left limb at around 1:30 a.m. on January 27. On examination, the patient was found to be drowsy, with slurred speech, left-sided facial palsy, left-sided limb hemiparesis, and cranial CT showed that the brain hemorrhage in the right basal ganglia area was about 20 ml. According to the patient’s condition, the possibility of spontaneous hemorrhage caused by congenital vascular malformation was considered high. On January 29, a cerebral angiogram was performed to confirm a small arterial malformation vascular mass at the deep penetrating branch of the right middle cerebral artery. Case 2: Yang, female, 24 years old, suddenly felt a numbness in her left hand, followed by dizziness, breath-holding, limpness, deep coma, convulsions, and bilateral dilated pupils at about 9:30 a.m. on January 27. An emergency CT check showed that the right frontoparietal brain hemorrhage had broken into the ventricle, with a volume of about 50 ml, and the midline was displaced and the ventricle was compressed and combined with brain herniation, so his life was in danger. The hospital immediately started the emergency green channel, and 37 medical and nursing staffs from 11 departments formed a strong rescue team to perform hematoma removal for the patient. During the operation, a 3×3 cm malformed vascular mass was found under the cortex of the right cerebral motor area. After careful treatment and care by the medical staff, the patient was released from life-threatening condition. Cerebrovascular malformation: an “untimely bomb” hidden in the brain Cerebrovascular malformation is a congenital, non-neoplastic developmental abnormality formed by the mutation of cerebral blood vessels during human embryonic development, mostly seen in young people, and is usually diagnosed at the age of 20-40. Cerebrovascular malformations are divided into cerebral arteriovenous malformations, cavernous hemangiomas, venous malformations, and capillary dilation. Among them, cerebral arteriovenous malformation is the most common type of cerebrovascular malformation, accounting for more than 90%. Cerebral arteriovenous malformations generally occur between the 45th and 60th day of embryonic development. During the fourth week of embryonic development, the primitive vascular network of the brain begins to form, followed by the differentiation of arteries, veins and capillaries. During this period, if localized cerebral vascular differentiation is impaired, it can lead to direct communication between the arterial and venous ends, resulting in a cerebral arteriovenous malformation. A cerebral arteriovenous malformation is actually an intertwined network of abnormal cerebral blood vessels of different diameters that communicate directly between the cerebral arteries and veins without capillaries and form a variable number of fistulas, hence the name congenital cerebral arteriovenous malformation. Cerebral arteriovenous malformations can occur in any part of the brain, more than 90% of them are located in the cerebellar vermis and most of them are distributed in the cerebral cortex. Cerebrovascular malformation is like an untimely bomb hidden in the brain, when it does not develop, most patients do not feel anything, and people do not go for cerebral angiography for no reason, so it is rarely detected before the onset. But once due to emotional excitement or other stimuli, such as drunkenness, smoking, high tension, or even sex, the thinned malformed blood vessel may break and bleed because it cannot withstand the sudden elevated pressure. Once the malformed cerebral vessels rupture and bleed, more than half of them have a poor prognosis and the mortality rate is as high as 25%, and some of them may become vegetative although their lives are saved by resuscitation. Intracranial hemorrhage is the most common and fatal manifestation of cerebrovascular malformation “The most common and fatal manifestation of cerebrovascular malformation, especially cerebral arteriovenous malformation, is intracranial hemorrhage.” Bleeding from cerebrovascular malformations occurs as a result of the pathophysiological basis of the malformed vascular mass and hemodynamic disturbances. Vascular walls within the vascular mass of cerebral arteriovenous malformations are unevenly thick and thin. Structurally, the arterial wall shows reduced or absent elastic fibers, thin or absent smooth muscle, and some of the vessel walls even have only a single layer or proliferation of endothelial cells and collagen fibers. The high flow of blood causes the artery with abnormal wall structure to dilate and twist, and the vessel wall is further damaged and destroyed, which will rupture and bleed locally once it cannot withstand the pressure of blood flow. At the same time, due to the lack of capillaries between the arteries and veins in the malformed vascular mass, the arterial blood flows directly into the veins and the resistance to blood flow suddenly decreases, resulting in a decrease in local cerebral arterial pressure and an increase in cerebral venous pressure, and this leads to a series of hemodynamic disturbances, and when a large amount of blood flow hits the malformed vascular mass, it will lead to local expansion of the veins and rupture and bleeding. Another damage caused by cerebrovascular malformation to cerebral vessels is the phenomenon of “blood theft”. A large amount of blood flows through the arteriovenous fistula in the cerebral arteriovenous malformation and is rapidly injected into the vein from the artery, resulting in a decrease in the local cerebral arterial pressure, resulting in the lack of normal perfusion of the surrounding brain tissue and the flow of arterial blood to the malformed part of the vessel, resulting in the phenomenon of “cerebral blood theft”. With long-term blood theft, the small arteries in the surrounding area are in a dilated state and the vascular structure is changed. Under certain circumstances, such as a sudden rise in systemic blood pressure, the dilated blood vessels may rupture and bleed. The key to prevention and treatment of cerebrovascular malformation lies in early detection and early treatment. Cerebrovascular malformation is like an untimely bomb buried in the brain that may explode at any time, if it can be detected early and treated reliably and securely as soon as possible, this untimely bomb hidden in the brain can become a dud that never explodes. Although the onset of cerebrovascular malformation is sudden, it is not without a hint before. For example, some patients often have throbbing headaches, and some may develop epilepsy and remain untreated for a long time; some children may have delayed development, visual impairment, hydrocephalus, and intracranial vascular murmurs; some newborns may have progressive high stroke volume heart failure, which is often misdiagnosed as congenital heart disease; some children show an inability to walk long distances at the age of 3-5 years, appear weak, and need to rest in place; some patients read with good grades during elementary school, and begin to perform well when they enter middle school. Some patients have good grades during elementary school and begin to decline when they enter the middle school level. He reminds that if you have these symptoms, you should think about whether it is a cerebrovascular malformation, and go to the hospital in time to find a specialist for examination and diagnosis, and preferably a cerebral angiography. With the continuous progress of medicine, the level of diagnosis and treatment of cerebrovascular malformation has been greatly improved, and there are various treatment methods available. Commonly used methods include endovascular embolization, surgical resection, stereotactic radiation therapy, and combination therapy. For cerebrovascular malformations with high blood flow, large malformed vascular masses and those located in important functional areas or cannot be reached by surgery, embolization therapy or embolization followed by surgery or stereotactic radiation therapy is applicable; for those small malformed vascular masses located on the brain surface or in non-important functional areas, surgical resection can be used; for those cases where neither endovascular embolization nor surgical resection is possible and no blood has been bled, Stereotactic radiation therapy; for older people with only headache and epilepsy symptoms can be treated conservatively with drugs, while paying attention to a good lifestyle and routine, avoiding staying up late, exertion, exertion and emotional excitement.