written by Michael Cole, OD, Child and Family Eye Care Center
There are many reasons headaches occur. The list of possible causes is long, and definitively identifying the cause is often challenging. One component of the body that should be at the top of the list to investigate is the visual system. When headaches are the complaint, a complete and thorough eye examination is warranted.
In our clinic, patients often surmise, “I’m getting headaches often, so I think I need glasses (or a new prescription).” Surprisingly, the one thing that is likely not to cause headaches is blurry vision. While blurry vision is bothersome, it is not likely to cause symptoms of pain. There are certain refractive errors that can cause undue eye strain, but hazy eyesight alone is likely not the culprit.
The most likely cause of headaches related to the visual system is fatigue. This is the type of headache that you might imagine starting mild and dull early on, only to intensify and worsen throughout the day. Most people complain of the pain being centered around the eyes, radiating upward through the scalp or laterally across the temples. Relief is often found by closing the eyes, turning down lights, or taking breaks.
Visual fatigue arises from how the eyes are used throughout the day. Our visual system stresses and tires with overuse — much like hard physical labor causes aches and pains from day to day and can cause chronic injury and discomfort over time. Visual tasks that are close to us are the most difficult for our visual system to endure. Think of the visual demands for a graphic designer, a bookworm, a gamer, or even a retiree cross-stitching the night away. With so much near work, it is no wonder we sometimes overload the system and kick off a headache.
Sometimes, there are conditions that limit visual stamina and cause symptoms earlier than we should normally experience. Binocular vision disorders that affect how well our eyes work as a team can limit our ability to maintain a clear image up close, converge both eyes to view targets up close, and limit our ability to change working distances quickly and accurately. It is important that vision examinations include the testing necessary to identify deficits of binocular vision.
In addition to testing the functional limits of the visual system, examination of the internal structures of the eye is particularly important when investigating headaches. If there is increased pressure inside the closed skull, the only routes for that increased fluid to escape are either down through the spinal cavity or forward through the optic nerve’s pathway into the orbit. This would cause the optic nerve to swell, which is visible upon examination. Optic nerve swelling would be indicative of what could be a very serious concern and would warrant cranial imaging immediately. Thankfully, these types of cases are rare, but it is imperative that we investigate to rule out the worst possibilities.
In order to treat vision-related headaches, often multiple approaches are needed to find relief. The ergonomics of near tasks can be improved to reduce the demands on the eyes. Frequent breaks are recommended. Often, prescription lenses are used to improve performance and relieve eye strain. Binocular vision disorders can be remediated by increasing the flexibility of the visual system by employing vision rehabilitation. Often with a comprehensive plan of action, visual-related headaches can be significantly decreased, if not completely resolved. For more information or to schedule an evaluation, please contact our office.
