Vision Issues After a Brain Injury
Our brains control everything we do—from regulating our breathing to keeping our minds racing at 2 A.M., to processing the very words you’re reading on this page. The brain is an incredibly far-reaching organ, but as such, any damage done to it can have dire consequences that aren’t often predictable. It may seem strange to learn that damage to the back of your head—or more specifically, to the back of your brain—can cause damage to your vision. Your eyes aren’t on the back of your head, after all. So exactly how are vision and brain injuries problems related? What are the important warning signs of vision issues to recognize? And how can such vision problems be treated?
The Biology Behind Your Brain and Vision
The optic nerve is a cable-like group of nerve fibers that connect and transmit visual information from the eyes to the brain. It receives light signals via photoreceptor cells called rods and cones, then sends those signals along its cable of fibers and into the visual cortex of the brain. This cortex is located in the occipital lobe at the bottom backside of the brain, or right inside the base of the skull. This lobe is responsible for essentially translating the light signals our eyes take in into recognizable visual imagery.
It’s easy to understand how some type of damage to your eye itself can impact your vision. If your cornea is scratched, your retina disconnected, or even your optic nerve is somehow damaged, it will likely have a direct correlation to some kind of vision loss or impairment. But because your brain’s visual cortex is actually responsible for “seeing” the light and objects in front of you, if you damage that cortex, you may directly damage your vision.
How Traumatic Brain Injuries Can Affect Vision
A traumatic brain injury (TBI) can result from any number of scenarios. A car accident, slip and fall, a blow to the head, or extreme neck and head movement can damage the skull, which can ultimately damage the brain. For example, whiplash experienced in the neck during a rear-end car crash can actually cause your brain to suffer a concussion.
By definition, a TBI occurs when a sudden trauma causes damage to the brain, whether externally (hitting the outside of the head) or internally (the brain is pierced by an object). Knowing this, it’s no wonder that many TBIs occur during contact sports or car accidents.
It’s estimated that up to 80% of patients who suffer a TBI struggle with some kind of vision deficit as a direct result of their injury. Physical harm to the visual cortex, concussions, and strokes can all cause vision issues, and each of those can be a direct result of a TBI. This type of damage can sometimes be severe enough to cause permanent vision loss. Other times, the injury may result in temporary vision loss or other vision conditions that can be treated or reversed.
If someone suffers a back-of-the-head injury, it may not become immediately apparent that their vision has been affected. It’s even possible that the person in question still has 20/20 vision—because 20/20 is not actually a measurement of “perfect” vision. Instead, it’s a measurement of a single visual function known as acuity, or the eye’s ability to discern details at twenty feet. A brain injury can affect a person’s vision in many other ways as well.
Some of the more common visions disorders that occur after brain trauma are:
- Double vision, or when the eyes do not align to the same point in space. It can be extremely disorienting, and as a result can create dizziness, balance difficulty, difficulty reading, difficulty walking, or a negative impact on other simple daily activities.
- Visual field defects, such as loss of peripheral vision. This can also be disorienting, and patients may exhibit symptoms like bumping into things when walking, difficulty seeing around their sides, difficulty reading, and possible effects on mobility and balance.
- Tracking problems, like the ability to follow a moving target or the ability to scan from one point to another. Tracking problems can often be physically recognized in the eyes by jerky or unstable movements of the eyeball.
- Eye coordination disorders, such as issues focusing. When the world looks permanently out of focus, it can result in blurred vision, double vision, eyestrain, headaches, motion sickness, disorientation, dizziness, or difficulty concentrating.
- Perceptual deficits, or difficulty making sense of the visual information presented to the brain. The occipital lobe/visual cortex is responsible for processing visual stimuli, so if it’s damaged, the patient could become confused trying to understand visual information, such as from a book, on a screen, or just navigating the world.
It’s also possible that the injured person may experience a complete loss of vision in one or both eyes. If someone who has suffered a head injury complains of this or any of the above symptoms, it’s important to take them to see an eye doctor or brain specialist as soon as possible. These doctors have an array of specific vision tests they can run to help your loved one determine if they might have suffered damage to their brain that is affecting their vision, and hopefully treat it.
Treating Vision Affected by a Brain Injury
Sometimes, a blow to the back of the head can temporarily affect the occipital lobe and a person’s vision. Reports of people like athletes hitting their heads or suffering blows and temporarily losing sight are not uncommon. But even if their vision comes back, it doesn’t mean the incident should go ignored.
There are plenty of cases in which full, regular vision may never be completely restored after a TBI occurs. It’s possible that the brain can suffer permanent damage causing lifelong vision disorders, thereby leading to necessary ongoing treatment. But because the human brain isn’t completely regenerative, especially in adults, treatment options don’t often include work on the brain itself. More often than not, treatment and therapy will relate directly to the eyes.
If you or a loved one has vision problems, some simple devices to help manage them might include:
- Corrective eyeglasses, which can help with blurry vision, improve distance sight, and make it easier to perform everyday activities like driving, reading, and watching television.
- Specialized glasses, which can assist with an array of different sight issues. For example, prism glasses are built into the lens and affect the way light enters the eye. This can help with things like double vision and visual field loss.
- Eye patches, though they may feel like the least flattering treatment option. But by placing a patch over one eye, information coming in through that eye is eliminated, effectively resulting in less information for the brain to process.
In some cases, it is possible to use therapy techniques to “retrain” the brain to see properly. This still involves a lot of “eye work” implemented by a trained professional like an occupational therapist. It may include specialized tests and exercises taken on by the eyes in the hopes of restimulating or regenerating certain parts of the occipital lobe and visual cortex. But there’s never a guarantee that a TBI will respond to such treatment positively.
Of course, there are some cases of TBIs leading to vision loss that becomes permanent. In these cases, where the patient has very little chance of recovering full or any eyesight, it’s important to help them adapt to their blindness and learn how to interact with the world in a new way. Suffering complete vision loss can be devastating, but it doesn’t have to be life-ending. There are many blind people in this world who are not only capable of living the life they want but who find ways to thrive.