Brain damage is brain injury that is either mild, moderate, or severe. This type of injury can involve either open head or closed head injury. Open head injuries occur when the skull is displaced or fractured by an outside force and closed head injury occurs when the skull is not displaced or fractured by an outside force. Some of the different types of brain damage include concussion, contusion, diffuse axonal injury, penetration damage, anoxic injury and hypoxic injury.
Hypoxic brain damage occurs when the level of oxygen is not sufficient enough to allow for normal body functioning. Stagnant hypoxia is also referred to as hypoxic ischemic brain injury and ischemic insult brain injury and the damage to the brain is caused by inadequate blood pressure or blood flow. Anoxic brain damage differs from the hypoxic type in that no oxygen at all reaches the brain. In anemic anoxia, the damage is caused from the lack of oxygen in the blood. In anoxic anoxia, the lack of oxygen to the brain causes the problem.
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Penetration brain damage is caused by an object such as a bullet or knife that brings the object or parts of the object and bone, hair and skin into the brain. Diffuse axonal brain damage occurs when the skull moves too fast for the brain such as in a car accident or in Shaken Baby Syndrome. A contusion is a bruise formed by blood on the brain due to head injury. Surgery to remove the contusion may be required if the bruise is large.
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A concussion is a sudden impact to the brain that affects the blood vessels and may sometimes cause a fatal blood clot. A loss of consciousness may or may not result in a concussion. Both blood vessels and nerves in the brain may be damaged and the concussion may take months or even years to heal.
Both open head and closed head brain damage may involve brain swelling, but closed head brain swelling is usually more dangerous as the brain has less room to enlarge in. The Glascow Coma Scale (GCS) is used to assess the degree of severity in terms of neurological damage. Mild injuries to the brain may involve a short loss of consciousness or just some confusion, while moderate injuries usually involve longer periods of unconsciousness and confusion. Severe brain damage may involve unconsciousness or a coma that will remain for several months.