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Home Resources Traumatic Brain Injury

Traumatic Brain Injury (TBI) - Levels of Severity

Mild TBI

  • Loss of consciousness is very brief, usually a few seconds or minutes
  • Loss of consciousness does not have to occur - the person may be dazed or confused
  • Testing and scans of the brain may appear normal
  • Most common: 75%-85% of all brain injuries are mild
  • 90% of individuals recover within 6-8 weeks, often within hours or days, but 10% experience deficits, which may not be evident immediately
  • More than one mild brain injury over time (e.g., sports injuries or domestic violence) increases the chance of deficits

Moderate TBI

  • Loss of consciousness lasts from a few minutes to a few hours
  • Confusion lasts from days to weeks
  • Physical, cognitive, and/or behavioral impairments last for months or are permanent
  • EEG/CAT/MRI are positive for brain injury

Severe TBI

  • Prolonged unconscious state or coma lasts days, weeks, or months
  • Categories include:
    • Coma
    • Vegetative State
    • Persistent Vegetative State
    • Minimally Responsive State
    • Locked-in Syndrome