What is strabismus?
A Strabismus (turned eye) is the term used to describe the condition where both eyes are not looking in the same direction. One eye looks at the object of interest, whilst the other eye looks in another direction (most often in towards the nose, or out towards the ear). Strabismus affects between 2% – 4% of the population and occurs equally in males and females.
A Strabismus can occur at birth, in early childhood (3 – 4 years of age) or after injury or illness. You may always notice the eye turn, or it may come and go. The eye turn will usually be more noticeable when the child is tired or unwell.
How does strabismus affect vision?
With normal vision, both eyes look at the same object. The brain fuses the two pictures into a single three-dimensional image. When one eye is turned, two different pictures are sent to the brain.
If strabismus occurs in a young child, prior to the visual system maturing, the brain learns to ignore the image form the turned eye. As a result, vision in the turned eye is weaker than the straight eye. This condition is called AMBLYOPIA. If Amblyopia is not treated early (prior to 8 years of age), then poor vision in the turned eye will persist and remain untreatable.
If strabismus occurs in adults, the patient may experience double vision (Diplopia).
How is strabismus treated?
- The cause of the turned eye is first established.
- The need for glasses is evaluated and sometimes these are prescribed as they can eliminate or reduce the size of the turn.
- If amblyopia exists, then occlusion therapy (patching) is prescribed to improve the vision, but this will not correct the turn.
- Sometimes the turn needs to be corrected with surgery. This involves surgically realigning the eyes so that both eyes are looking in the same direction. Surgery may also be performed to improve the cosmetic appearance of the turn, in order to avoid teasing by other children and to improve social skills and self-esteem.
Q. What will the glasses do?
A. Sometimes the strabismus is associated with a focusing error, either long or short sighted. For example, children who are long sighted need to work their focusing systems harder, which in turn can produce a secondary turn in the eye. Glasses can be used to either control the turn, stimulate vision or as a simple vision aid to help you to see better. Some children require glasses for one or more of these problems. Your doctor will advise which problem the glasses are being used for.
Q. How long will he need to wear glasses for?
A. This varies from one child to another. He will need to be monitored every few months and the glasses will need to be adjusted as he grows up. Depending on the degree of “long sightedness” some children can grow
out of the glasses
Q. What is patching for?
A. Some children develop a “lazy” eye meaning they significantly favour using one eye over the other. As a result the weaker eye gets neglected and does not develop the full visual potential. Patching the dominant eye stimulates vision development in the weaker eye.
Q. What if my child does not like patching?
A. That is quite normal. The extra effort of using the weaker eye can be very tiring. As the vision improves, however, the patching will generally become easier. Short term rewards (sticker books) and games can help with the initial patching. Your doctor can advise if you need support.
Q. If he needs surgery, is it safe at his young age?
A. Modern anaesthetics are relatively very safe. Obviously there is a risk with anything we do . The risk to his life from anaesthetics is extremely low. The risks to his eye from the surgery are very small. Some children may need more than one surgery to achieve their best results.
Q. Do I need to get my other children examined?
A. If there is any concern it will be a good idea.