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Concussion

• Overview
• Symptoms
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Definition:

A concussion is a brain injury that may result in a bad headache or unconsciousness .

See also: Concussion - first aid

Causes, incidence, and risk factors:

There are more than a million cases of concussions each year in the United States.

A concussion may result when the head hits an object or a moving object strikes the head. A concussion can result from a fall, sports activities, and car accidents. Significant movement of the brain (jarring) in any direction can cause unconsciousness. How long a person remains unconscious may indicate the severity of the concussion.

Often victims have no memory of events preceding the injury, or immediately after regaining consciousness. More severe head injuries can cause longer periods of memory loss (amnesia).

Usually, a person has the most memory loss immediately after getting hurt. Some of the memory comes back as time goes by. However, complete memory recovery for the event may not occur.

Bleeding into or around the brain can occur with any blow to the head, whether or not unconsciousness occurs. If someone has received a blow to the head, they should be watched closely for signs of possible brain damage.

Things to watch for include repeated vomiting, unequal pupils, confused mental state or varying levels of consciousness, seizure-like activity, weakness on one side of the body or the inability to wake up ( coma ). If any of these signs are present, immediately call your health care provider.

• Review Date: 3/21/2006
• Reviewed By: Eric Perez, MD, Department of Emergency Medicine, St. Luke's-RooseveltHospital Center, New York, NY. Review provided by VeriMed HealthcareNetwork.

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