19 July 2022
How is a concussion caused?
A concussion occurs when you experience a head injury – usually a blow to the head – that causes the brain to move back and forth inside your skull. The impact of your brain hitting your skull as it moves can cause it to become bruised, bringing on a variety symptoms. In severe cases, a head injury can lead to brain damage as the violent movement of the brain can lead to chemical changes in the brain, or damage to brain cells. Having said that, the strength of the blow to the head doesn’t always dictate the severity of the concussion. Even a mild blow to the head can cause a concussion or brain injury with devastating long-term impacts.
What are the symptoms of a concussion?
There are a number of symptoms that might suggest you have a concussion following a head injury. Not all of the symptoms of a concussion are vision-related, and it’s possible that effects to your vision might not come immediately after sustaining a head injury and concussion. Symptoms of a concussion which don’t necessarily relate to your vision are:
- Nausea and vomiting
- Confusion and disorientation
- Blacking out
- Irritability and mood changes
- Balance issues and dizziness
These symptoms can last anywhere from a few hours or days to up to a year in severe cases. It’s crucial that you allow your brain to rest after a concussion to help these symptoms clear up as quickly as possible and decrease your chances of suffering with long-term concussion-related symptoms. Resting your brain involves not going back to work or school too soon as any form of stimulation, including watching TV or trying to read, can negatively affect your recovery.
What are the different ways a head injury affects your vision?
Problems with vision affect up to 82% of people who have experienced a concussion following a head injury. The length of time that these problems persist depends entirely on the severity and nature of the head injury. Some of the most common symptoms which affect your vision include:
- Light sensitivity
- Blurry vision
- Double vision
- Loss of visual field
- Eye pain
- Itching and redness
- Problems reading from digital screens
- Visual irritability
- Vertical heterophoria
Light sensitivity is a very common vision-related symptom of a concussion. You might find it particularly difficult to be in bright sunlight or fluorescent lighting following your head injury, as the force of the blow to your head can cause displacement in pain-sensitive brain structures. To manage this, you might find it easier to wear sunglasses until the discomfort subsides.
Blurry vision and double vision are also relatively common after a concussion. This is due to head trauma causing damage to the muscles and nerves around the eye, disrupting the alignment of the eyes. This misalignment is what can lead to blurred or double vision, and in turn cause issues with balance and dizziness.
Loss of vision is one of the scariest visual symptoms caused by a head injury. If the impact of the head injury causes broken blood vessels in the eye, or any swelling and bruising, you may experience some blind spots in your visual field.
Eye pain can come in a number of forms, whether that’s a dull ache that lasts days or stabbing pains that come sporadically throughout the day. You might also experience a burning sensation or itching as a result of the concussion, anywhere from a few days to as long as a year after the trauma.
Visual irritability is something you might experience in busy environments, or when trying to focus on patterns and moving objects. This feeds into the disorientation that you might experience as a result of a head injury. Experts suspect that it occurs because of problems with your central nervous system, brought on by the concussion.
Vertical heterophoria is a rare eye condition which can be worsened by a head injury. This is where your eyes are vertically misaligned, so one eye is higher than the other. Your brain knows this and tries to compensate for the confused visual images your brain receives, which can lead to eye strain. You might also feel dizzy and experience eye pain as a result.
When should you visit a doctor about your vision?
If you notice visual symptoms after hitting your head or acquiring head injury, it’s best to seek medical advice from your doctor. While temporary visual changes are very common after a big blow to the head, it’s recommended that you get checked and then closely monitor any further changes to your vision. Generally, the quicker you notice any symptoms, the sooner any necessary treatment can be administered. Your sight is perhaps your most important sense, so taking steps to protect it couldn’t be more crucial.