If a large blow to the head may result in a hematoma, fracture, or concussion, a CT scan can be performed to assist in the diagnosis and is recommended. If a violent blow to the head is followed by conditions that may include a scalp hematoma, skull fracture, intracranial hematoma, and concussion, a CT exam may be performed to aid in diagnosis and differentiation. If the blow is light and only causes a scalp hematoma, and there is no obvious abnormality in the CT examination, ice can be applied to reduce the swelling; if the hematoma is larger it can be punctured and then drained, and then bandaged. If the blow is stronger, it may cause skull fracture, CT examination can see the fracture line and whether there are compression symptoms, etc. Those with symptoms need surgery. If there is a blow to the head and an intracranial hematoma develops, CT examination can help with diagnosis and differentiation. Epidural hematoma CT images show biconvex mirror-shaped or bow-shaped high-density shadow; subdural hematoma shows crescent-shaped shadow, CT images can play a role in assisting diagnosis. If a head injury leads to concussion, its CT examination is not abnormal, and the diagnosis is mainly based on the history, clinical manifestations and so on. If the head has been struck. CT examination is recommended to assist in diagnosis and treatment.