Diagnosing Concussion

Head injuries, also referred to as traumatic brain injuries, are the result of a sudden trauma. This may include a hit to the head, any jarring event that shakes the brain inside the skull, or an object piercing the skull and damaging the brain tissue. Doctors often use the terms “head injury” and “traumatic brain injury” interchangeably.

A concussion is a mild form of a traumatic brain injury. It is caused by a blow to the head or the body that shakes the brain inside the skull, which can damage brain tissue and disrupt brain function. A concussion may result from a fall, a car accident, or an assault. Increasingly, this injury is being seen in young people as a consequence of involvement in sports, such as football, soccer, hockey, lacrosse, gymnastics, and skiing.

At NYU Langone’s Concussion Center, our experts diagnose concussion in both children and adults, determining the best course of treatment for each person.


Most concussions do not result in loss of consciousness, and many people with a concussion recover within a few days to several weeks. Signs and symptoms of a serious traumatic brain injury that requires emergency attention may include:

  • confusion
  • persistent vomiting
  • severe headache
  • difficulty falling asleep, or sleeping more or less than usual
  • changes in speech or walking patterns

Some head injuries result in serious complications, such as bleeding in the brain tissue and the layers that surround the brain.

A person with a more severe head injury may have these same signs and symptoms, in addition to the following:

  • a headache that worsens or does not go away
  • repeated vomiting or nausea
  • convulsions or seizures
  • an inability to awaken from sleep
  • slurred speech
  • weakness or numbness in the extremities
  • loss of coordination and falls
  • increased confusion, restlessness, or agitation

In rare circumstances, some people have no symptoms for hours or even days after a concussion. However, it is important that anyone with a head injury be evaluated immediately to reduce the risk of serious complications, such as seizures, changes in cognitive ability, or bleeding or swelling in the brain.

Doctors at the Concussion Center at NYU Langone evaluate and, if necessary, manage any symptoms caused by injuries to the head and brain.

Diagnostic Tests

There is no single test used to diagnose a concussion. If your NYU Langone doctor suspects a concussion, he or she may perform a physical exam to check your strength, balance, coordination, and reflexes.

Your doctor also asks questions about your medical history, including details about the injury—its cause and when it occurred, for example—and any symptoms you have noticed. Your doctor may also ask questions that test your ability to pay attention, learn, remember, and solve problems.

The following tools may also be used in making a diagnosis.

CT Scans

A CT scan is a type of X-ray that creates detailed images of your tissue and internal organs. These images can show whether your brain is bruised, swollen, or bleeding.

MRI Scans

A doctor may order an MRI scan to better view the brain and determine whether there is any swelling or bleeding. MRI uses a magnetic field and radio waves to create two- or three-dimensional pictures that may reveal smaller areas of bleeding and bruising in the brain.

Neuropsychological Testing

Evidence of a concussion may not always be visible on MRI or CT scans, so a doctor may perform neuropsychological tests to determine if you are having difficulty with cognition and memory after a concussion. These tests may also detect any emotional changes.

A neuropsychological test may involve answering questions or performing tasks. For example, to test for attention span and memory, the doctor might ask you to repeat a series of numbers, letters, or words. To test for language and speech skills, you might be asked to name the objects in pictures or as many words as you can think of that begin with a certain letter.

Neurodiagnostic Testing

To help diagnose a brain injury and pinpoint its location in the brain, NYU Langone doctors might perform a neurodiagnostic test called EyeBoxCNS to track eye movements. A person with a suspected brain injury watches a small picture move on a computer screen for a few minutes while a device tracks the person’s eye movements.

Pioneered at NYU Langone, the technology detects weakness in the nerves that move the eye. This correlates to the location and nature of the brain injury, helping our doctors to better develop a treatment plan.

King-Devick Sideline Test

The King-Devick test is a screening tool for an injured athlete that is used on the sideline of a playing field. It can help to gauge the likelihood that a person has a concussion.

After a suspected head trauma, the athlete is given this two-minute test, during which he or she is asked to rapidly read single-digit numbers displayed on cards or on a mobile device. If the time needed to complete the test is longer than the time recorded at preseason baseline, the athlete is removed from play and evaluated by a healthcare professional.

NYU Langone physicians are investigating if the results of these tests can help to confirm a concussion diagnosis on the sideline.

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