Acute cerebrovascular diseases (ACVD), or stroke, is a multi-morbid and common disease that occurs mainly in middle-aged and older adults. Approximately 200,000 people die from cerebrovascular disease in the United States each year. No accurate statistics are available for China. It is speculated that the incidence of acute cerebrovascular disease in China has a tendency to increase compared to developed countries. Because of the cruelty of acute cerebrovascular disease, which either causes death of patients or lifelong neurological defects, how to actively prevent and treat acute cerebrovascular disease is an important research topic. The causes of stroke are numerous and the pathological process is complex, but the basic pathological process of stroke is based on lesions of the vessel wall combined with changes in blood composition and hemodynamics, resulting in hemorrhage or ischemic infarction. Therefore, all factors that can affect the function of the vessel wall, blood composition and hemodynamic changes are considered to be the etiology of acute cerebrovascular disease. In recent years, with the progress of science and technology, environmental factors and changes in human life patterns, there is a tendency to increase the number of strokes in young people, or to make the diagnosis of cerebrovascular disease in young people, which could not be diagnosed or even misdiagnosed, simple and easy due to the application of instruments such as CT, MRI, MRA, DSA, TCD, etc. Szots statistics from 1988 to 1998, a group of young people with stroke Atherosclerosis accounted for 33.3%, prethrombotic states (15.5%), cardiogenic emboli (8.5%), unknown cause (17.7%), improvement (77.4%), deterioration (3.6%), and death (7%). Young people are the most valuable years of life, the pillar of the family and the backbone of the business. It is more and more important to correctly diagnose and treat cerebrovascular disease in young people, or to detect the risk factors of cerebrovascular disease in young people at an early stage in the subclinical stage. 1, common causes of stroke thrombosis: small vessel thrombosis causing lacunar infarction, large vessel thrombosis causing large cerebral infarction embolus occlusion: carotid bifurcation, aortic arch and arterial entrapment when arterial plaque dislodged causing arterial-arterial embolus occlusion. Cardiac emboli: atrial fibrillation, appendage emboli, myocardial infarction, dilated cardiomyopathy Cardiac valve damage: mitral stenosis, mechanical valves, bacterial endocarditis Singular emboli: atrial septal aneurysm due to atrial septal defect, patent foramen ovale 2. Uncommon causes of stroke Spontaneous hypercoagulable state Protein C deficiency Protein S deficiency Anticoagulant III deficiency Antiphospholipid syndrome Factor V Leidon mutation ( Factor V Leiden mutationProthrombin G20210 mutationSymptomatic malignancySickle cell anemiaβ-thalassemiaTrue erythrocytosisSystemic lupus erythematosusHomocysteinemiaThrombothic thrombocytopenic purpura) diffuse intravascular coagulation abnormal proteinemia nephrotic syndrome inflammatory bowel disease venous sinus thrombosis muscle fibrous dyskinesia vasculitis systemic vasculitis (PAN, Wegner’s syndrome, Takayasu’s syndrome, giant cell arteritis) primary central nervous system vasculitis meningitis (syphilitic, tuberculous, mycobacterial, bacterial, zoster virus) cardiogenic (mitral valve calcification, atrial mucinous tumor, intracardiac tumor, nonbacterial embolic endocarditis, wasting endocarditis, lei _ endocarditis) subarachnoid hemorrhage secondary to vasospasm drugs: cocaine, amphetamines Moyamoya disease eclampsia.