What is amblyopia?

Amblyopia is a condition where one eye develops abnormally in early life. The weak, or 'lazy', eye often wanders inwards or outwards. In rare cases, both eyes can be affected. If left untreated, amblyopia can lead to permanent vision loss in the affected eye.

The condition usually occurs in children between birth and age 7 years, and is the leading cause of decreased vision in one eye in children. Amblyopia is more common in small or premature babies, or children with a family history of the condition.

What causes amblyopia?

Amblyopia develops when one eye receives weaker visual signals in early life. Since the brain receives these fewer visual signals, it starts to ignore input from that eye, and the eyes do not work together properly. One eye then appears to be ‘lazy’ as it doesn’t move together with the other eye.

Amblyopia can be caused by anything that blurs a child's vision or causes crossed eyes.

Common causes include:

• an imbalance in the muscles that position the eyes (known as strabismus)
• a difference in the sharpness of vision (visual acuity) between the eyes
• an imperfection on the surface of the eye (astigmatism)
• any problem with one eye, such as a cloudy area in the lens (cataract)

What are the symptoms of amblyopia?

A key sign of amblyopia is when one eye appears to be ‘lazy’ as it doesn’t move together with the other eye.

Other signs that you, your baby or child might have amblyopia include:

• an eye that wanders inwards or outwards
• squinting or shutting one eye
• head tilting
• poor depth perception (the ability to see in three dimensions, including an object’s size and how far away they are)

Learn more about eyesight in children.

When should I see my doctor?

See your doctor or visit an optometrist if you notice symptoms of amblyopia. See a doctor if you notice one of your baby’s eyes wandering in their alignment at any time following the first few weeks after birth. It is also a good idea to have your child’s eyes tested before they start school.

Take your child to their doctor or visit an optometrist if they are showing symptoms of amblyopia. Treatment is most successful if started early — ideally before the age of 8 years.

How is amblyopia diagnosed?

Amblyopia is diagnosed by a doctor, community nurse, optometrist or ophthalmologist (specialist eye doctor). To diagnose amblyopia, your health professional will ask about your family’s eye health history, examine your (or your child’s) eyes and carry out an eye test.

In around 1 in 4 people, amblyopia recurs after treatment. This is why it is important to have your child's eyes checked by your doctor or optometrist regularly, even after treatment ends.

You don’t need a referral from your doctor to see an optometrist. If your doctor or optometrist thinks you should see an ophthalmologist, they will give you a referral.

How is amblyopia treated?

The type of treatment will depend on the cause of amblyopia and whether it is affecting your child's vision.

The earlier treatment for amblyopia starts, the better the outcome. This is because it is important to correct the condition while the connections between the eyes and the brain are forming.

Some treatments are designed to strengthen the weaker eye by forcing the brain to use it instead of the stronger eye. These include covering the stronger eye with a patch or temporarily blurring its vision with special drops. This treatment usually works within several weeks or months, although it can continue for up to 2 years.

If amblyopia is caused by eye conditions such as near-sightedness, far-sightedness or astigmatism, your doctor may prescribe glasses or contact lenses.

If cataracts or droopy eyelids (ptosis) are a problem, your doctor may recommend surgery.

Resources and support

For more information on eye health and for help finding an optometrist visit Optometry Australia.

Queensland Health provides information on amblyopia (lazy eye) in children, including when to seek help, treatment and tips for helping your child.

Do you prefer to read in languages other than English?

Vision Australia offers a guide to their services in a range of community languages.

Looking for information for Aboriginal and/or Torres Strait Islander people?

Read more on eye health for Aboriginal and/or Torres Strait Islander people at HealthInfoNet.

Visit The Fred Hollows Foundation to learn 5 Things You Should Know About Aboriginal Eye Health.