Most cerebrovascular malformations are congenital, meaning that they occur in the womb. Is it true that the most common group of cerebrovascular malformations is children or even young children? In fact, it is not the case. Most of the people who are diagnosed with cerebrovascular malformations are those who have obvious symptoms, and this is mostly in young people aged 20-40. Why? It turns out that these patients with cerebrovascular malformations do not have any symptoms in the early stage, or the symptoms are very hidden and easy to be ignored. After a certain age, cerebrovascular malformations rupture and bleed or seizures occur and cause serious symptoms, leading patients to go to the doctor and be diagnosed. So, what are the typical symptoms of cerebrovascular malformation? What symptoms should be alerted? First, headache: according to the size and location of cerebrovascular malformation, not everyone has headache symptoms, even if the headache symptoms are not the same. However, there are common points. First, the headache site is often fixed. Second, the headache tends to be a vague, dull pain, and is particularly prominent in patients with small amounts of localized bleeding or oozing blood. This needs to be differentiated from migraine. Second, blood theft symptoms: Most often seen in patients with large size of cerebrovascular malformation and fast blood flow within the malformed mass. The blood flow in the area where the vascular malformation is located flows from the artery, rapidly through the vascular malformation mass, and is drained out by the vein. In contrast, the brain tissue around the cerebrovascular malformation does not receive enough nutrients, which is called “blood theft”. This results in localized brain softening, necrosis, and even dysfunction. The symptoms are often different depending on the location of the malformation, and can be manifested as mental retardation, loss of muscle strength of the limbs, etc. Third, epilepsy: cerebrovascular malformation often causes local neuronal degeneration, necrosis, and in heavy cases, it can be seen as desheathing, softening, microcysts, microcysts, and even cyst formation; there can be iron-containing heme deposits, tissue cell reaction, amyloid vesicles, calcification and glial cell hyperplasia, etc. Some local brain tissue shows obvious atrophy, etc. Even small arteriovenous malformations can occur. These pathological changes can easily induce seizures, or “epilepsy”. The manifestations of epilepsy are diverse, including “frothing at the mouth”, “slanting of the mouth and eyes”, and “cramping” of the limbs. Fourth, the rupture of vascular malformation bleeding caused by brain pressure, irritation symptoms: a significant number of patients are found because of the rupture of vascular malformation bleeding caused by a series of symptoms. It is manifested as subarachnoid hemorrhage or intracerebral hematoma. Severe headache, nausea, vomiting, mental abnormalities, hemiparesis, aphasia, dyslexia and dyscalculia may occur, as well as vertigo, diplopia, eye tremor and gait instability.