In patients with cerebrovascular blockage, the first step is to determine whether there is cerebrovascular blockage, based on the symptoms of its onset, i.e., the presence of hemiparesis, vomiting and headache. Secondly, MRI should be performed as soon as possible, because MRI is the most accurate than CT to determine whether there is an infarction or not. CT examination may not show obvious changes on the first day, and the image will change only after 24 hours. In addition, the analysis of the severity of cerebral infarction should be based on a combination of symptoms, examination results, etc. First of all, it is judged whether there is a large infarction. If there is no large infarction and the symptoms are not severe, it is a relatively mild case. If there is severe headache, vomiting, coma and other comparative manifestations, the condition is more serious, and the severity is also judged according to the size of blocked blood vessels.