Concussion and Vision

Published September 16, 2020

Author: Dr. Aaron Nichols

Excel Neuro-Optometric Clinic

The term concussion has become increasingly popular in the last several decades.

The research behind the causes and management of a concussion is constantly growing, and is now showing the importance of providing optometry and eye care  for optimum treatment outcomes.

Following a concussion, a patient may experience:

  • Double vision
  • Headaches
  • Fatigue while reading
  • Words moving on the page

Do any of these symptoms sound familiar? 

If you answered ‘yes’, then you are likely not alone. Concussions which are also referred to as mild traumatic brain injuries, have been proven through research and studies to affect the visual system.

It has been shown that up to 90 percent patients will experience visual problems following a concussion. 

Three key parts of the visual system that are commonly affected by a concussion include:

  1. Vergence eye movement – eye teaming, or pointing the eyes at the same place, simultaneously
  2. Version eye movements – eye tracking, or  eye movements used for reading
  3. Accommodative system – focusing system, or the ability to see print clearly for reading, computer work and other near tasks

20/20 vision and normal eye health is simply not enough

Given the complexity of the visual system, simply assessing central visual acuity and ocular health is not sufficient.

Many optometrists practice only primary eye care. Your primary care optometrist will complete an eye exam, and normally inform you on your visual acuity (i.e., 20/20 vision), and ocular health. Although this exam may be seen as comprehensive it often does not assess the whole visual system.

After sustaining a concussion, it is important to assess how the visual system is performing, and in particular how the three systems mentioned above— vergence, version, and accommodation— are functioning.

If these systems are not assessed, patients may be told that their vision is fine, that they have ‘20/20 sight’. While this may be true for sight and eye health, it may not address important aspects of the visual system, leaving many patients frustrated and confused.