What Is Traumatic Brain Injury?  /  Classification of TBI  /  Classification Criteria

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Classification Criteria

Transcript

Lt Col Reynolds
A brain injury is classified as a mild TBI or concussion when the patient experiences any of the following:

  • A loss of consciousness, or LOC, lasting for up to 30 minutes. LOC with a mild TBI is uncommon.
  • Alteration of consciousness, or AOC, for up to 24 hours, or
  • Post-traumatic amnesia, or PTA, for up to 24 hours.

Structural imaging tests, such as a CT scan or MRI, are not usually conducted for mild TBI patients. If an imaging test is done, the results will be normal.

Maj Hemstad
A brain injury is classified as a moderate TBI when the patient experiences:

  • LOC that lasts more than 30 minutes but less than 24 hours
  • AOC that lasts more than 24 hours, or
  • PTA that lasts one to seven days

Structural imaging tests will be done for a patient with a moderate TBI. The results may be normal or abnormal.

Lt Col Reynolds
A brain injury is classified as a severe TBI when the patient experiences:

  • LOC that lasts more than 24 hours
  • AOC that lasts more than 24 hours, or
  • PTA that lasts longer than seven days

As with moderate TBI, structural imaging tests will be done for severe TBI patients, and the results may be normal or abnormal.

Maj Hemstad
The structural imaging of a moderate to severe TBI, like a mild TBI, can be normal. However, if structural imaging is abnormal, the TBI is classified as being at least moderate in severity. If a patient meets criteria in more than one severity category, they will be classified at the higher level of severity. For instance, if a person loses consciousness for two hours, as is typical with a moderate TBI, but only experiences three hours of post-traumatic amnesia, as with a mild TBI, their injury will be classified as moderate.

Lt Col Reynolds
The Glasgow Coma Scale, or GCS, is a test used by many healthcare providers to determine the level of consciousness and classify the severity of injury. It measures a person’s ability to open their eyes and respond to spoken questions and physical prompts for movements. While the test is easy to administer, reliable, and serves as a good indicator or prognosis for recovery following TBI, the Department of Defense has recommended against using GCS scores in diagnosing TBI.