Vision loss

One of the effects of brain injury that has a major impact on daily living is changes in vision. Our eyesight is something many of us depend on, and when you experience changing vision or vision loss, this can be scary and difficult. You aren’t used to it, and it makes completing acts of daily living harder. You also experience intense emotions related to the change or loss of your vision which can include depression, grief, and anger.

This is all perfectly normal. Changes or loss of vision are difficult, and require you to change your entire way of living. It’s important that you use whatever supports you can to help you navigate these changes. You will need to work with specialists such as neurologists and eye doctors (optometrists) to determine if the vision deficits you are experiencing are temporary or permanent. Since recovery takes a long time, it may be awhile before your medical team can determine what vision deficits are temporary and what are permanent.

If your vision loss is long-term or permanent, ophthalmologist or optometrists will tell you if you need corrective lenses, glasses or surgery. No matter what kind of vision problems you’re experiencing, you will need to learn new ways to complete tasks and coping mechanisms to help you adjust to your new situation. This could include working with an occupational therapist to set up your home environment as well as assisting you with how to complete activities of daily living as independently as possible. You may also consider meeting with an optometrist can teach you how to take care of and use your remaining vision. 

Topics in this section include:

How the brain controls vision

In order for your vision to work properly, your brain must be able to complete the following functions:

  • The eyes must move together and focus on objects
  • Nerve receptors at the back of the eye (retina) must then send messages back along the optic nerve
  • The occipital lobe at the back of the brain must catch or capture these messages

The occipital lobe is the area of the brain that has the most control over vision. It processes the images we see, including patterns, shapes and colours. Damage to the occipital lobe can cause a range of vision problems, including blindness.

Other areas of the brain that contribute to vision functioning are the parietal lobe and the frontal lobe. The parietal lobe helps us with navigation, depth perception, and how to move around the objects we see. The frontal lobe is the decision-making part of the brain: it decides how to respond to the information your other lobes supply. While they don’t control as much of our vision as the occipital lobe, they still play a part in correctly analyzing and responding to what we see. Damage to these lobes could lead to vision changes.

Vision problems after brain injury

Blurred vision

When there is damage to the visual cortex of the brain or to the eye and the nerve receptors, you may experience blurry vision. This is also called visual acuity loss. It is similar to what people who need glasses experience. For example, your vision may be similar to someone who is near-sighted: objects close up may be clear and easy to see, while objects that are further away are blurred.

How blurred vision is treated depends on the degree of loss you’re experiencing. In some cases glasses or surgery can help correct the problem. You will need to work with an optometrist to determine the best course of treatment for you.

Blurry vision is also a side effect of fatigue, which is a common effect of brain injury. If you’re getting tired or looking at something too long, objects may start to become blurred, your eyes may ache, or you may experience headaches. In this case corrective eyewear may not be helpful. Instead, try taking more breaks and giving your eyes a rest when you are completing visual tasks such as reading.

Sensitivity to light

Also known as photophobia or photosensitivity, sensitivity to light means you have trouble adjusting to changes in lighting and struggle with bright lights such as fluorescents or even sunlight.

Some tips for managing sensitivity to light include:

  • Wear tinted sunglasses to help reduce light and glare
  • Set up appropriate lighting in your home and work environment that is low-impact on your eyes and brain
  • Avoid using technology with screens unless they have the proper backlighting and contrast. Using a screen in the dark can be hard on anyone’s eyes, and can be especially difficult for those with light sensitivity
Double vision after brain injury

Double vision (also known as diplopia) happens when the eyes don’t move exactly together, causing the person to see two of everything. This makes it hard to decide exactly where objects are. Someone with double vision is likely to bump into furniture, spill or drop items. It’s disorienting, and can cause a person to feel dizzy or nauseous.

If you are experiencing double vision sometimes an eye patch or glasses with prism lenses are prescribed. To reduce the risk of bumping into objects, items such as furniture need to stay in one place and not be moved. This will help you familiarize yourself with your environment. You should also try eye drops if you are also experiencing dry eyes – sometimes that dryness causes strain which can cause double vision.

Whatever the cause of double vision, you should see an ophthalmologist or optometrist if you are experiencing it, as they will be able to recommend the best course of treatment.

A drooping eyelid

A drooping eyelid (also called ptosis) may block your vision in the affected eye. This changes how you see, and it may take a while for your vision to adjust even if the drooping is temporary.

It’s hard to judge distances using only one eye. You may experience the following problems:

  • Dizziness
  • Miss seeing objects
  • Not know how fast objects are moving towards you, or how close they actually are
  • Have trouble pouring

Drooping eyelids can sometimes be treated with special glasses or surgery.

Vision loss

In some cases, a person may lose part or all of their vision. This can be temporary or permanent. Losing sight is incredibly difficult to cope with, and will require the person to adapt their daily lives. These adaptations are emotionally and mentally demanding, and can impact the survivor’s wellbeing. When coping with the changes that come with a brain injury, it is important to take care of mental health as well.

Our vision is broken up into fields. A good analogy is that our eye is like a pie, and each slice is a field of vision. You can lose slices of the pie but still retain some: in other words, you have partial vision. The type of vision loss you experience is dependent on what pieces of the pie you lose. Types of vision loss associated with brain injury include hemianopia, quadranopsia, and complete monocular visual loss.

Hemianopia is blindness involving one-half of the visual field in both eyes. This means you only have 50% of your vision in each eye. Depending on what part of the brain is damaged, this could mean you could have vision on the same side of each eye (i.e. the left side), or on different sides (i.e. you have vision on the right side in your right eye and left side in your left eye) [1]. It could also mean you have vision in the top part of your eye, but not the bottom part. This is an example of partial blindness.

Quadranopsia is the same as hemianopia, except instead of losing 50% of vision, the person loses 25%. It is also classified as partial blindness. Other examples of partial blindness include losing peripheral vision or loss of vision from the centre of the eye moving outward [2].

Different people with partial blindness will retain different parts of their vision depending on their individual circumstances. When a person is experiencing partial loss of vision, they may experience some of the following challenges:

  • Suddenly notice objects that seem to appear or disappear as they can’t see that part of their environment
  • Bump into objects on the affected side
  • Not see food on the side of the plate on the affected side
  • Turn their head toward the unaffected side
  • Lose track of the last place on a page where they were reading or writing
  • Cut words in half when reading, which can make it hard to figure out what the word is

Headaches and eye pain

Some effects of brain injury, including vision problems, can lead to headaches and eye pain. This includes eyes feeling dry, sore, and itchy. The muscles around the eyes may feel painful as well. You may also be experiencing headaches related to your vision problems when you are trying to focus on an object or task.

Headaches can be treated with medication (but you should not overuse). If you are experiencing eye pain, speak with your optometrist or another member of the medical team. For at-home fixes, you can try:

  • Taking breaks where you close your eyes
  • Adjusting the lighting in your home
  • Using saline/tear solutions for dryness and itchy eyes

Legal blindness

In the definition provided by the Canadian National Institute for the Blind (CNIB), legal blindness is a level of blindness that has been defined by law to limit some activities for safety reasons, such as driving, or to determine eligibility for disability-related government programs and benefits. Someone is considered to be legally blind [3] when:

  • Visual acuity is 20/200 (or 6/60) or less in both eyes after correction, and/or
  • A visual field of 20 degrees or narrower

This means that you are able to see very little, or you are not able to see at all.

Returning to work with vision changes

If you are interested in working, it’s possible to find a job or use adaptations that make working with vision loss possible.

See sources

Disclaimer: There is no shortage of web-based online medical diagnostic tools, self-help or support groups, or sites that make unsubstantiated claims around diagnosis, treatment and recovery. Please note these sources may not be evidence-based, regulated or moderated properly and it is encouraged individuals seek advice and recommendations regarding diagnosis, treatment and symptom management from a regulated healthcare professional such as a physician or nurse practitioner. Individuals should be cautioned about sites that make any of the following statements or claims that:

  • The product or service promises a quick fix
  • Sound too good to be true
  • Are dramatic or sweeping and are not supported by reputable medical and scientific organizations.
  • Use of terminology such as “research is currently underway” or “preliminary research results” which indicate there is no current research.
  • The results or recommendations of product or treatment are based on a single or small number of case studies and has not been peer-reviewed by external experts
  • Use of testimonials from celebrities or previous clients/patients that are anecdotal and not evidence-based 

Always proceed with caution and with the advice of your medical team.