I. Stroke (stroke): commonly known as cerebrovascular accident, stroke. A patient is brought to the hospital and the doctor finds that the patient has symptoms of brain dysfunction, such as hemiplegia, unclear speech (aphasia), etc. At this time, there is no or no way to do a cranial CT test, so we do not know the specific cause of the brain dysfunction, in which case the patient is said to have had a stroke. Stroke is characterized by high incidence, high disability, high mortality and high recurrence. In 2012, the third national survey of causes of death showed that stroke was the leading cause of death, with a rate of 22.45%. The chart below shows the distribution of stroke mortality rates around the world. Unfortunately, China has the highest rate of death due to stroke in the world, while Europe, Oceania and North America have the lowest stroke mortality rates in the world. In China, the number of deaths due to stroke is about 200 per 100,000 population per year!