Cerebrovascular malformation does not refer to arteriovenous malformation, but arteriovenous malformation is only one kind of cerebrovascular malformation. Cerebrovascular malformations are divided into: 1) hemangioma; 2) capillary malformation (capillary dilation); 3) venous malformation (venous malformation); 4) spongy malformation (cavernous hemangioma); 5) arteriovenous malformation (no arteriovenous shunt); 6) arteriovenous shunt malformation; (1) cerebral (soft meningeal) arteriovenous malformation; (2) soft meningeal arteriovenous fistula; ( (3) carotid cavernous sinus fistula; (4) dural arteriovenous fistula (dural arteriovenous malformation); (5) Galen arteriovenous malformation (Galen arteriovenous fistula); 7, mixed malformations. The most common type is the arteriovenous shunt type malformation. At first glance, the classification of cerebrovascular malformations is dazzlingly diverse. Simply put, blood enters the brain through the large arteries, passes through the small arteries, enters the capillary bed, and then flows back out of the brain through the veins. Malformations can occur at one or more locations along these pathways. It is easy to understand this by naming the vascular malformations according to where they are located. Cerebral arteriovenous malformation is a type of arteriovenous shunt malformation that occurs in the brain parenchyma. It is a congenital vascular dysplasia, and the lesion may occur in the fourth month of embryonic development when the earliest and most primitive blood circulation to the brain tissues is gathered into larger tubular-like abnormal structures. It may also occur after the vascular plexus develops into arteries and veins causing a persistent linear short circuit between them, where abundant blood from the blood supplying arteries flows into the veins causing them to dilate and distort. There are many similarities between the development of the brain and the expansion of a city. The growth of blood vessels during the development of the brain is similar to the planning of roads during the expansion of a new city, with residential areas living around roads. The better the road planning, the more convenient the life of the residents. And vice versa. If there is a mistake in the process of vascular development, a certain part of the brain tissue becomes a “forgotten corner” and the arteries and veins are directly connected, it becomes a brain arteriovenous malformation. The area becomes an “old city”, “inaccessible” and “economically backward”. These problems will cause a series of symptoms and consequences. Are all cerebrovascular malformations due to congenital development? Actually, it is not quite true. A carotid cavernous sinus fistula can be caused by trauma. Dural arteriovenous fistulas, on the other hand, are mostly the result of acquired development.