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Strabismus, commonly known as ‘turned’ or ‘lazy’ eye, occurs when the eyes point in different directions. The eye can turn inwards or outwards, and it may be constant or intermittent.

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How common is strabismus?

Strabismus is the most common eye disorder in children. It’s estimated that between 3 and 5 per cent of the Australian population are affected by strabismus.

What causes strabismus?

The causes of strabismus are varied. The condition can be caused by abnormalities in the eye muscles or within the nerves that control these muscles.  Strabismus can also occur in people with low vision. In some cases, strabismus can be a sign of a more serious eye disease, so it should always be promptly investigated to determine its cause.

How is strabismus detected?

Strabismus can be difficult to detect, particularly in children. It’s recommended that all children undergo an eye examination by a suitably qualified health practitioner before starting school. Children who experience changes to their vision or the appearance of their eyes should undergo a thorough eye examination.

Can strabismus cause low vision?

When we look at an object the brain receives two different visual images, seen from a slightly different angle. The brain then puts these two images together to ‘see’ a single image, with some depth (3D vision)  When the eyes point in different directions, the brain will ‘see’ double. In young children, the brain relies on the straight or ‘good’ eye for visual information and ignores the turned eye instead of seeing double. This leads to poor vision development in the turned eye or amblyopia, also known as ‘lazy eye’. Children who develop amblyopia may experience vision problems.  In most cases, amblyopia can be successfully treated before the age of 8 or 9 years. That is why it is so important to diagnose and treat it early. Over a person’s lifetime amblyopia can lead to a greater risk of blindness as accidents or other diseases can affect their one remaining good eye. This may affect their ability to drive a car.

Who develops strabismus?

There are many different types and causes of strabismus. Risk factors include a family history of the condition, long-sightedness and low vision. Adults with no history of strabismus can also develop the condition,will often experience double vision and should seek prompt medical attention.

How is strabismus treated?

Vision problems caused by strabismus can be prevented if treated early. Strabismus treatment aims to improve the alignment of the eyes. This is often achieved with glasses, surgery or both. An eye patch may be used to improve the vision loss.. Untreated childhood strabismus will persist into adulthood.

What research is CERA conducting into strabismus?

Researchers at CERA contributed to the discovery of a gene linked to a rare and complex form of strabismus. This collaborative research with Children’s Hospital Boston is now being expanded to investigate the genes associated with the common forms of childhood strabismus. In addition, our Twins Eye Study confirmed the heritability of eye turns and work continues in this area.  It is hoped this research will lead to new treatments and ways to prevent the condition.

How can I help?

You can support strabismus research at CERA by making a donation.