Lt Col Reynolds
Diagnosis of moderate to severe traumatic brain injury is based primarily on the classification criteria that determine the severity of the injury. These criteria include:

  • Loss of consciousness
  • Alteration of consciousness or mental state
  • Post-traumatic amnesia, or loss of memory surrounding the event, and
  • Structural imaging as seen with a CT scan or MRI

Dr. Freeman, can you tell us how these criteria are used to diagnose moderate to severe TBI?

Dr. Freeman
Of course, Dr. Reynolds. A person who has experienced trauma to the head will be diagnosed with a moderate TBI if any of the following are true:

  • The trauma caused them to lose consciousness for 30 minutes to 24 hours
  • The trauma caused them to feel dazed and confused for more than 24 hours, or
  • They experience post-traumatic amnesia, or PTA, for one to seven days

On the other hand, if a person who has experienced a head trauma loses consciousness for more than 24 hours or experiences PTA for more than seven days, they will be diagnosed with severe TBI.

It’s important to note that although the Glasgow Coma Scale, or GCS, is widely used in clinical practice, the Department of Defense has recently recommended against using GCS scores for diagnosing TBI. Because it’s so widely used, however, it’s useful to know what it is, and what score indicates a moderate TBI and a severe TBI.

The Glasgow Coma Scale measures a person’s ability to open their eyes, as well as their ability to respond to spoken questions and physical prompts for movements. A GCS score between 9 and 12 indicates moderate TBI. Anything below a 9 indicates severe TBI.

A provider may order imaging tests if they have reason to believe that other damage to the skull or brain has occurred. Serious problems can arise if there are conditions that haven’t yet presented symptoms, such as a hematoma, or bleeding, in or around the brain.