The most common situation is that after the head is hit by the ball, there will be headache, dizziness, nausea, vomiting, there is no coma, there is no memory loss, it is a traumatic brain injury reaction, as long as rest 3-7 days there is no big problem, there is no life threatening, there is no sequelae. However, if a coma occurs after being hit by a ball, or even a transient memory impairment, forgetting what just happened after waking up, there may be a concussion reaction, and this time you must go to the hospital for a head CT examination to clarify the trend of the development of the disease. In more serious cases, the coma may last for more than half an hour, which may cause cerebral contusions, and it is necessary to go to the hospital for examination and active treatment, and serious cerebral contusions may even be fatal, so it is necessary to clarify the specific development.