What is a squint?

A squint, or strabismus, is present when the two eyes are not looking in the same direction. It may be apparent all the time or only when the person is tired, unwell or focusing on a near or distant object. The eye may turn in or out or one eye may sit higher than the other. A squint may vary depending on the gaze position.

Babies often have the appearance of a squint due to a wide bridge of the nose and this appearance is lost as the face develops. However, a child with a true squint will not grow out of it, so all children suspected of a squint must be seen by an eye specialist.

Squints can also be seen in adults, as a long-standing problem or following a nerve palsy.

What causes the squint?

Squints may occur in families and may arise in the first few months of life. They may also appear in older children. In early onset squint the child has a poor ability to use the eyes together (binocular vision) and in later-onset squints binocular vision is quickly lost.

Children may be long-sighted in which case the effort of focusing to see clearly may lead to a squint. Glasses alone may correct this problem.

Very occasionally a child may develop a squint because an eye is abnormal and has defective sight. The earlier this is detected the sooner treatment can be started.

If a child squints with one eye the vision in that eye will become lazy as the brain ignores information from the deviating eye.

What are the effects of a squint?

• a child may develop a lazy eye, (poor visual development) which if not corrected will lead to poor sight in that eye
• a child will lose binocular vision
• a squint may spoil one's appearance
• in adults the main symptom is often double vision.

When should treatment start?

Children suspected of a squint should be seen without delay by an eye specialist. No child is too young to be seen. In adults a squint from a nerve palsy may recover on its own and treatment is therefore only undertaken once the squint has stabilised.

What is the treatment?

Glasses will be prescribed if there is a focusing error, particularly with long-sightedness.

If a child squints with one eye only then this eye will become lazy. The other eye is patched so the child has to use the lazy eye. The aim is to build the vision in the poor eye to achieve a state where the child will use either eye to see. The squint will then switch from one eye to the other. This is called alternation.

If the appearance of a squint is obvious then surgery is carried out to move the eye muscles and thereby straighten the eye. In some cases surgery is performed early in an effort to achieve binocular single vision.

In children, surgery is usually performed between the ages of six months and four years, and in adults it may be performed at any convenient time once the squint has stabilised. Squint surgery is performed as a day stay procedure under general anaesthesia.

For further information and support talk to an optometrist or eye specialist. Optometrists are listed in the 'Yellow Pages' of your telephone book. Eye specialists are listed with registered medical practitioners at the front of the white pages of your telephone book.

Original material provided by Auckland Eye, and reviewed May 2005. Edited by everybody.