Acute subdural hematomas are divided into acute subdural hematomas and chronic subdural hematomas. Acute subdural hematomas appear on CT of the skull as a high-density hemorrhagic shadow under the intracranial plate and outside the brain tissue crescent, while acute subdural hematomas can be combined with cerebral contusions and appear on CT as a high-density hemorrhagic shadow within the brain tissue. Acute subdural hematoma requires observation of the degree of combined cerebral edema, the degree of midline displacement of the brain, the thickness of the subdural hematoma, and the size of the cerebral sulci, pools, and ventricles on CT. Chronic subdural hematomas appear on CT as isointense, hypointense, or mixed-density hemorrhagic shadows under the intracranial plate and crescentic shape outside the brain tissue, and the degree of midline shift in the brain.