Eye Tracking Helps Diagnose Concussions

The eyes have been called the 'window to the soul'. They are also a window into the brain and are being used to help diagnose concussions. Doctors and trainers are currently using eye tracking skills to help assess for the presence of a concussion, or mild traumatic brain injury (mTBI). Research is also under way to determine how eye tests can help athletes, military personnel, and anyone else who takes an unfortunate fall or is involved in a motor vehicle accident.

Concussions are top of mind for just about everyone these days. Concussions are the subject of Hollywood movies, the hallmark injury of current military conflicts, and the top priority of coaches, parents and players at every level of competition; from the pros down to the kids stepping onto the field for the first time. Concussions, just like any other form of traumatic brain injury (TBI), can have cognitive, physical and emotional effects that can last for months or even years.

What many people do not realize is that a concussion can affect the visual system in several ways (and we are not talking about seeing stars). It is important to know that no two concussions are the same. People will experience a variety of symptoms that vary in severity, onset and duration. Visual symptoms that you should be aware of include:

• Blurred or fluctuating vision: Deficits in eye focusing (accommodative dysfunction), or a reduced ability to compensate for a minor prescription can result in blurred or fluctuating vision.

• Double vision: More than half of traumatic brain injury patients see double. Often, double vision is only present intermittently and patients may not even realize that what they are experiencing is double vision. One major cause of double vision following a concussion is convergence insufficiency, or a reduced ability to use the eyes together during near activities.

• Eye tracking deficits: Difficulties with reading or computer work is extremely common after a concussion. This is one reason why eye tracking tests are used to help diagnose concussions.

• Light sensitivity: Many concussion patients will find that they are bothered by certain types of light, even when indoors.

• Reduced cognitive abilities: Feeling like you are 'in a fog'? Difficulties with concentration, memory and thinking quickly are very common in concussion patients.

• Balance difficulties/dizziness: The visual system has a strong influence of balance. When vision conditions are present, it can affect your balance and create dizziness and nausea

• Headaches: Evaluation of the eyes should be considered when headaches are present, especially when they occur at the end of the day or after visual activities (reading, computer work, etc).
   

Deficits in eye tracking, teaming and focusing are pervasive in the post-concussion population, and researchers are using this to their advantage when developing diagnostic testing for concussions. Here are just a few examples of how eye tracking is being used to help evaluate concussions.

King-Devick Test: This eye tracking test is currently used as a sideline concussion screening test. It is quick, easy to administer and comes in both paper and electronic (to be used on a tablet) formats. This eye tracking test only takes 1-2 minutes to administer, allowing trainers, coaches and parents to more appropriately determine if an athlete should be pulled from the game.

Eye-Trac Advance: Due to the growing concern over concussions among military personnel and athletes, the Department of Defense began funding the Eye-Trac Advance study to evaluate eye tracking and its relationship to attention and reaction time. Neurosurgery 2014

Brief Vestibular/Ocular Motor Screener (VOMS): Researchers at the University of Pittsburgh are evaluating oculomotor (tracking), vergence (eye teaming), vestibular-ocular reflex and visual motion sensitivity in post-concussion athletes. Their findings suggest that assessment of visual functions should be included as a component of a comprehensive approach to the assessment of concussions. American Journal of Sports Medicine 2014.

Whether vision deficits are detected using the King-Devick test or suspected based on increased difficulty with visual tasks (reading, eye-hand coordination, etc), the most appropriate next step is to schedule a Neuro-Optometric Assessment with an optometrist who is residency-trained in binocular vision, neuro-optometry and vision therapy. This will allow any vision conditions that are present to be properly diagnosed and treated. Nothing is worse than having a vision condition go undiagnosed (especially if a doctor told you that everything was fine without doing the proper testing). The right diagnosis will allow the doctor to design a rehabilitation program for your visual system. Neuro-Optometric Vision Rehabilitation is extremely effective in treating post-trauma vision conditions, letting you get back in the game or back to your old self.