CT brain can detect early cerebral hemorrhage, cerebral infarction 24 hours after the onset of the disease, cranial trauma, intracranial infection and cranial brain tumors. 1. Early cerebral hemorrhage: Early cerebral hemorrhage patients are often preferred to confirm the diagnosis of CT brain, patients can be based on the results of CT head to clarify the bleeding site, bleeding volume and other disease information. 2. Cranial trauma: CT brain can clarify the severity of cranial trauma and the scope of damage according to the fracture line of the skull and the contusion and edema of the brain parenchyma. 3. Intracranial infection and craniocerebral tumor: CT brain can confirm the diagnosis of intracranial infection and craniocerebral tumor according to the abnormal signal shadow in the cranium and the occupation situation. In addition, brain CT can also detect cerebral atrophy, cerebral degenerative disease, cerebral parasitic disease and other diseases, which is fast, accurate and convenient, and patients are recommended to follow the doctor’s instructions for standardized diagnosis of diseases.