Cerebral contusions and lacerations involve structural brain damage and thus are more serious than concussions, which are an alteration in mental function or level of awareness caused by an injury that does not cause visible damage to brain structures.
Contusions may be caused by the sudden fast movement (acceleration) of the brain against the skull after a jolt—as may be delivered by a forceful blow to the head—or by the sudden stopping (deceleration) that occurs when a moving head strikes an immovable object (as when a person's head hits the dashboard or the steering wheel in a frontal-impact motor vehicle crash). The brain can be damaged at the point of impact and on the opposite side when it strikes the inside of the skull. Contusions may get larger in the hours and days after the injury, causing brain function to deteriorate.
Cerebral lacerations occur when an object or a piece of bone penetrates the skull (causing a skull fracture) and tears brain tissue.
Contusions and lacerations can cause bleeding or swelling in the brain.
Contusions and lacerations may be very small, causing only minimal damage to the brain, with few symptoms or symptoms of minor head injury. However, if injuries are large or if swelling or bleeding from a small injury is severe, people may have symptoms of severe head injury. For example, people often are unconscious for a short time (such as a few minutes or less) or longer. When awake, people often are drowsy, confused, restless, or agitated. They may also have vomiting, seizures, or impaired balance or coordination. The ability to think, control emotions, move, feel, speak, see, hear, smell, and remember may be impaired. A more severe injury causes swelling within the brain, damaging brain tissue further. Herniation of the brain may result, sometimes leading to coma.
Doctors do computed tomography (CT) to diagnose a contusion or laceration.
If bleeding and swelling in the brain are minor, people are hospitalized and observed, usually for up to a week.
If bleeding is severe, doctors treat them as if they had a severe head injury. Often people are admitted to an intensive care unit. Doctors keep the blood pressure and blood levels of oxygen and carbon dioxide at desirable levels. To help people breathe, doctors may give them supplemental oxygen through a face mask or insert a breathing tube through the mouth into the windpipe and provide them with mechanical ventilation.
Pain is treated as needed. People may need to be sedated because too much muscle activity can increase the pressure in the brain and further affect brain function. Fever is treated. If seizures occur, anticonvulsants are given.
To measure pressure in the brain, doctors may implant a pressure gauge inside the skull or insert a catheter into one of the internal spaces (ventricles) within the brain.
If bleeding leads to herniation, the blood may need to be surgically removed to prevent compression of the brain. However, if removing the blood involves removing brain tissue, then brain function may eventually become impaired.