Brain CT is a commonly used auxiliary examination in neurology. Brain CT can detect intracranial fractures, intracranial infections and intracranial tumors. 1. Intracranial fracture: when there is a trauma, you can check whether there is any fracture by cranial CT. 2. Intracranial infection: CT for intracranial infection, if severe infection is present, the presence of abscesses may be seen, hydrocephalus may be seen, and the widening of the cerebral space below the arachnoid membrane is an indirect response to intracranial infection. 3. Intracranial tumor: CT of the brain can detect tumors in different locations, which may show cystic changes, necrosis, calcification and other lesions with different characteristic morphology and density, and enhancement scans may show different degrees of enhancement. Cranial CT can also detect sinus occupation, sinus inflammation, orbital lesions, cranial osteomyelitis, cranial metastases and scalp masses. When performing a CT scan, it is important not to agitate or shake the head, as this can affect the accuracy of the scanning image.