Kids Health Info

Brain injury - Eyes and vision

  • There can be changes to the way a person sees after a brain injury has occurred.  This can include problems with the field of vision, the position of their eye and how the eye moves. There are different treatments and strategies to help reduce or adapt to vision related difficulties.

    What can happen?

    The visual system is large and complex. The picture travels from the eyeball to the occipital cortex at the back of the brain (see Figure 1). Information is received by the eyeball and then transferred in special nerves to the back of the brain where it is decoded into what we 'see'. The occipital lobe is the area of the brain where information processed by the eyes is decoded and information about what we see (colour, shape and distance) is understood.

    ABI Lobes of the Brain

    Figure 1: Lobes of the brain

    Injury to any part of this pathway can lead to problems with eyes and vision (See Figure 2). Problems with eye positions (squint or strabismus, double vision), eye movements (jerky eyes, nystagmus, poor tracking), visual field defects and vision problems are common after a brain injury. Over time these visual difficulties tend to improve.

    ABI Visual Pathways

    Figure 2: Visual pathways

    Symptoms

    Double vision

    Double vision (diplopia) is caused by an imbalance of the eye muscle movements. The two images, one from each eye, are not aligned properly and so the child sees this as a double image. A child may close or cover one eye to look at something or have difficulty with balance or judging depth. They may have difficulty reading and copying. The child may have a squint or turn of one of their eyes.

    Visual field defect

    Visual field defect (hemianopia) is due to an interruption of the visual pathways in the brain. The result is a loss of vision in one half of the visual field in each eye (See Figure 3). A child may not pay attention to one side, may bump into objects on one side of the body or only draw on one side of a page.

    ABI Visual Field Defects KHI RCH

    Figure 3: Visual field defects - depend on the area of the visual pathway damaged

    Poor visual acuity

    Poor visual acuity is when you cannot see clearly. This is tested by using eye charts with letters or pictures. Special tests are available to test those children who cannot name pictures or read letters.

    Squint

    Squint (strabismus) is when the eyes are not in line with each other. Children may tilt or turn their head to try and line the eyes up because the eyes cannot correct the position themselves.

    Treatment

    Eyeball problems

    If the problem with vision is because of an eyeball problem, glasses can sometimes help.  However, glasses are not usually helpful after a brain injury. Ways to compensate for the problem are needed while the child's eyes and vision recover.

    Double vision

    Patching one eye can relieve double vision. It is important to swap eyes with the patch so that one eye does not become weak from lack of use. Patching can also help strengthen the muscles that cause a squint. To help a squint, the eye with better vision is patched making the weaker eye work and straighten its position.

    Poor visual acuity

    There are a number of things that can be done to help a child with poor visual acuity:

    • Reduce the amount of information presented on a worksheet.
    • Enlarge pictures and writing.
    • Have well contrasted pictures (i.e. strong black and white) in books.
    • Use felt tipped pens for drawing and writing.
    • Make sure the child has good lighting and good seating for school and homework.
    • Use a slope board on desks if the child has difficulty looking down.

    If a child has a very severe vision impairment, Vision Australia should be involved. They provide a comprehensive service for home and school to help children with vision difficulties.

    Visual field defects

    Teaching children to look or scan left and right will help them be aware of people or objects in their 'blind spot'.

    Who do I see and how is it diagnosed?

    • Your local doctor, paediatrician or neurologist can assess eyes and vision. They may refer your child to see an ophthalmologist and an orthoptist.  
    • An ophthalmologist is a doctor who specialises in disorders of the eye.
    • An orthoptist is a person who specialises in assessment of eyes and vision.
    • Most children who have difficulties with eyes and vision after a brain injury see both an ophthalmologist and an orthoptist.

    Key points to remember

    • Problems with eye movements and positions, visual field defects and vision problems are common after a brain injury.
    • Over time, the visual difficulties tend to improve.
    • A local doctor, paediatrician or neurologist can assess eyes and vision and can refer your child to see an ophthalmologist and/or an orthoptist.

    For more information

    Developed by the RCH Paediatric Rehabilitation Service. Based on info from the Brain Injury Service, at Westmead Children's Hospital (with permission). First published February 2007. Updated November 2010.

Kids Health Info app

The app will enable you to search and browse more than three hundred medical fact sheets and work offline.


Disclaimer
This information is intended to support, not replace, discussion with your doctor or healthcare professionals. The authors of these consumer health information handouts have made a considerable effort to ensure the information is accurate, up to date and easy to understand. The Royal Children's Hospital, Melbourne accepts no responsibility for any inaccuracies, information perceived as misleading, or the success of any treatment regimen detailed in these handouts. Information contained in the handouts is updated regularly and therefore you should always check you are referring to the most recent version of the handout. The onus is on you, the user, to ensure that you have downloaded the most up-to-date version of a consumer health information handout.