Tests and diagnosis

By Mayo Clinic Staff

Because traumatic brain injuries are usually emergencies and because consequences can worsen swiftly without treatment, doctors usually need to assess the situation rapidly.

Glasgow Coma Scale

This 15-point test helps a doctor or other emergency medical personnel assess the initial severity of a brain injury by checking a person's ability to follow directions and move their eyes and limbs. The coherence of speech also provides important clues. Abilities are scored numerically. Higher scores mean milder injuries.

Information about the injury and symptoms

If you observed someone being injured or arrived immediately after an injury, you may be able to provide medical personnel with information that's useful in assessing the injured person's condition. Answers to the following questions may be beneficial in judging the severity of injury:

  • How did the injury occur?
  • Did the person lose consciousness?
  • How long was the person unconscious?
  • Did you observe any other changes in alertness, speaking, coordination or other signs of injury?
  • Where was the head or other parts of the body struck?
  • Can you provide any information about the force of the injury? For example, what hit the person's head, how far did he or she fall, or was the person thrown from a vehicle?
  • Was the person's body whipped around or severely jarred?

Imaging tests

  • Computerized tomography (CT). A CT scan uses a series of X-rays to create a detailed view of the brain. A CT scan can quickly visualize fractures and uncover evidence of bleeding in the brain (hemorrhage), blood clots (hematomas), bruised brain tissue (contusions) and brain tissue swelling.
  • Magnetic resonance imaging (MRI). An MRI uses powerful radio waves and magnets to create a detailed view of the brain. Doctors don't often use MRIs during emergency assessments of traumatic brain injuries because the procedure takes too long. This test may be used after the person's condition has been stabilized.

Intracranial pressure monitor

Tissue swelling from a traumatic brain injury can increase pressure inside the skull and cause additional damage to the brain. Doctors may insert a probe through the skull to monitor this pressure.

Oct. 12, 2012