Ask the Physician: Dr. Lehr on Concussions and Vision
How often is vision affected in concussion?
A recent study found that over 90% of outpatients with mTBI had one or more visual impairment, including difficulty with eye movements, focusing, and eye alignment. Basically, the eyes were not working well together during visual tasks, such as tracking a moving target, shifting eyes from target to target, or holding steady gaze on a target.
What are the most common visual symptoms?
The visual symptoms can be subtle and at times, fatigue or brain fog may be blamed. However, one of the most common visual issues in concussion is difficulty keeping the eyes pointed to the same position in space while focusing the eyes to that same point. That is why objects may appear to move, be seen as double, or blur in and out of focus. Sometimes the impairment is noticed when attempting to focus quickly from near to far or far to near. You may feel uncomfortable when making eye contact or you may not be able to tolerate complex visual environments, such as the grocery stores or patterned flooring.
Other visual problems include light sensitivity, headaches, double vision, fatigue, dizziness, difficulty reading, or loss of peripheral awareness. You may feel the need to wear sunglasses when inside, particularly if you are exposed to fluorescent lights. Visual tasks involving the computer or prolonged reading may require more time than usual, and tend to be more confusing and fatiguing. Another common complaint is eye pain and discomfort, which at times is caused by staring to maintain focus, which dries the surface of the eyes.
What tests are needed to detect these visual problems?
A comprehensive vision evaluation must evaluate the health of the eye, as well as the visual processing system. The examination must include oculomotor (eye movement), binocular vision (eye teaming and alignment), and accommodative (focusing) testing. In addition, it is important to evaluate how the brain is processing the visual information through visual perceptual testing.
What can be done to alleviate these issues?
Once the vision evaluation detects the visual problems, a course of treatment can be prescribed. Remediation of the visual system may require specific lenses or prisms in glasses, lubricating drops, training exercises, and/or tinted filters to reduce light sensitivity.
Dr. Debra Lehr is a Neuro-Optometrist with Wills Eye Hospital at the Jefferson Comprehensive Concussion Center.