CT for acute stage of closed head injury.
Brain damage after head injury can be classified by its time course. Primary damage that includes acute subdural hematoma (SDH), acute epidural hematoma (EDH), and intraaxial lesions that include contusions, diffuse axonal injury (DAI), and intracranial hemorrhage (ICH), occurs at the moment of impact and is thought to be irreversible. Secondary damage that includes herniations, diffuse cerebral swelling, and secondary infarction and hemorrhage, evolves hours or days after injury as a consequence of systemic or intracranial complications. The duration and severity of secondary damage influence outcome. Head injury management is focused on preventing, detecting, and correcting such secondary damage. CT has been widely used for the neuromonitoring of head trauma. CT is the gold standard for the detection of intracranial abnormalities and is a safe method for survey. While MRI is more sensitive and accurate in diagnosing cerebral pathology, CT is considered the most critical imaging technique for the management of closed head-injured patients in the acute stage. In this article, we review the imaging findings and literature of various lesions of closed head injury in the acute stage.