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Some common childhood eye conditions explained…

Amblyopia (sometimes called ‘lazy eye’) is a developmental disorder that leads to reduced vision. It usually only affects one eye and occurs because the eye and the brain are not working together properly.

The affected eye looks normal, but sends weak ‘neuro electrical signals’ to the brain. This causes the brain to favour the other eye. The breakdown in the number or quality of the ‘neuro electrical signals’ being sent to the brain by the affected eye can be caused by a number of different factors including:

• reduction in the amount of light entering the eye
• a lack of focus in the eye
• confusion between the eyes – where the two images aren't the same (such as a squint)

Early diagnosis, before the child is eight years of age, and compliance with the treatment prescribed are vital to ensure vision is fully restored. Without treatment vision may be permanently damaged.

Treatment is usually broken down into two parts. First the underlying cause of the breakdown in communication between the eye and the brain is corrected – this typically involves the prescription of glasses to correct the focus of the eye.

The child is then encouraged to use the affected eye again. This might be done by using an eye patch to cover the dominant eye, or eye drops to temporarily impair the vision in the dominant eye.

Modern research has also lead to electronic gaming playing a part in the treatment of this condition.



Astigmatism is the name given when the front of the eye is slightly misshapen – more like a rugby ball than a round football. This uneven shape distorts light as it enters the eye throwing both near and far objects out of focus.

Astigmatism can occur on its own or together with long- or short-sight.

If a child has uncorrected astigmatism, they may have difficulty reading and concentrating at school.

The condition can be detected during a routine sight test and be easily treated by wearing glasses (or contact lenses for older children) to change how the light is focused.


Hyperopia (long-sightedness) occurs if the eye doesn't focus light on the retina (the light-sensitive layer at the back of the eye) properly causing close objects to appear blurred. Children and young adults with lower levels of long-sightedness can often adapt to overcome the problem because the lens inside the eye is still very flexible so they may mask the need for treatment.

Long-sightedness can affect one or both eyes. Regular sight tests are vital for early detection.

Where the extent of the focusing error is more  severe glasses may be prescribed to prevent eyestrain or the development of a squint.


Myopia (short-sightedness) can be difficult to spot in young children as they won’t know that what they are seeing isn’t normal. It occurs when the eyes grow slightly too long, preventing light from reaching the retina at the back of the eye and distorting focus so that objects in the distance appear blurry.

Myopia often runs in families and typically appears in childhood between the ages of six and 13.

Glasses (or contact lenses) are prescribed to correct vision by focusing the light on the retina at the back of the eye.

Early diagnosis and vision correction can help slow progression of the condition.

Squint (or strabismus) is a condition where the eyes point in different directions and ‘see’ different images. This confuses the brain and causes blurred or double vision. Left untreated the brain will often favour the information sent from one eye and suppress information sent from the fellow eye leading to the development of amblyopia.

Squints can be inherited or caused by a range of other factors such as short- or long-sightedness, astigmatism or illness. They usually develop in children under five but can develop in older children and even adulthood. It is not always possible to tell if the eyes are pointing in different directions by simply looking at someone so regular eyetests are vital to ensure diagnosis and effective treatment to prevent avoidable sight loss.

Treatment varies depending on the cause and severity of the squint, but might include:

Spectacles to correct any sight problems, especially long-sight
Patching where amblyopia has developed to encourage the weaker eye to be used
Exercises to encourage the eyes to work as a team
Injections to strengthen weakened eye muscles
or, Surgery to realign the eyes.