The causes of acute cerebral infarction are about the following: I. Large artery atherosclerosis, this type of cerebral infarction patients are mostly seen in middle-aged and elderly people, who usually have risk factors for cerebrovascular disease, such as hypertension, diabetes, coronary heart disease, hyperlipidemia, etc. The patient’s large blood vessels in the brain gradually atherosclerosis, the formation of thrombus in the lumen of the blood vessels, and finally the occlusion of blood vessels to form cerebral thrombosis. Second, exogenous embolism, refers to various emboli in the blood with the blood flow into the cerebral vessels and block the blood vessels. Common emboli include heart emboli, atherosclerotic plaque shedding emboli, fat emboli, etc. Third, small vessel occlusion is due to the occlusion of small vessels in the deep penetrating branches of the brain under the effect of long-term hypertension, which is usually called lacunar cerebral infarction. Fourth, other rare causes, such as cerebrovascular malformation, vasculitis, blood disorders, etc.