What is a Lazy Eye?

It is estimated that one in fifty children develop a lazy eye. They are often diagnosed during routine eye tests, so it is a good idea to book your child in for an optician’s appointment before they reach school age (usually around four years old).

What is a lazy eye?

A lazy eye, also known as amblyopia, is an eye condition where the eye does not develop normally. This means that vision is impaired in that eye, so a child will begin to rely on their stronger eye instead.

Treatment is available to correct, or help, a lazy eye so it is important that if you suspect your child may have any problems with their vision that you get medical attention for them and start treatment as quickly as possible.

An untreated lazy eye can sometimes lead to significant visual impairment in later life.

What is it like to have a lazy eye?

The lazy or problem eye is weaker than the other eye and develops vision issues. In very young children this might be hard to spot and they may find it difficult to articulate what the problem is.

Psychologists do not believe that children develop a theory of mind until they are around 4–5 years old. This means that very young children fail to grasp that other people have different thoughts, feelings and emotions to them. This means that, quite literally, they assume everyone sees the world in the same way that they do.

If children are having vision problems, unless prompted, a very young child might not mention it as they will assume everyone else sees in this way as well.

You may notice that if you cover your child’s eyes with your hand, they are unbothered when you cover their lazy eye but dislike having their ‘good eye’ covered. If they do react differently to having each eye covered, this is a sign that their vision is not equally good in both eyes and you should make them an appointment to get this checked out.

Parents, schools, nurseries or childcare providers may spot signs that a child is struggling to see properly, as this might affect:

• Drawing.
• Writing.
• Reading.
• Playing a game like ‘I spy’.
• Watching TV.

If you are concerned about your child’s vision, or any aspect of their development, you can speak to your GP who will be able to refer them to a specialist if necessary.

What causes a lazy eye?

A lazy eye develops because one eye fails to build a strong link to the brain. As it usually only affects one eye, children begin to rely more on the other eye as their vision will be clearer through the unaffected eye.

If you think of the eye as being like a camera, light passes through the lens and reaches the retina which is a light-sensitive tissue located at the back of the eye. The light is turned into electrical signals by special cells known as photoreceptors which, in turn, travel to the brain via the optic nerve. The brain is then able to combine the signals from each eye and turn them into pictures – this is how we are able to see.

From birth, the brain and eyes begin to form vital connections to one another. In the case of a lazy eye, the brain connections that help us to see do not form properly. During the first eight years of life, the brain needs to be sent a clear picture of the world by each eye. This allows the brain to build up strong pathways of communication with the eyes.

A lazy eye can happen if:

• Not enough light is entering the affected eye.
• Lack of balance between the eyes/confusion (when the image that the brain receives is not the same from each eye).
• A lack of focus in the affected eye.

What are the signs and symptoms of a lazy eye?

The most common symptom of a lazy eye is weakened or blurred vision in the affected eye. If left untreated this will usually get worse.

A lazy eye can be characterised by the affected eye turning inwards (towards the nose) or outwards (away from the nose) rather than looking to the centre. This is also indicative of a squint.

Other childhood vision problems that can make one eye appear different from the other include:

• Short-sightedness (myopia) – where you struggle to see objects that are far away clearly.
• Long-sightedness (hyperopia) – where close-by objects appear out of focus, but far away objects are clear.
• Astigmatism – when the eye shape resembles a rugby ball and light is more focused on one area resulting in blurred vision and headaches.
• Childhood cataracts – these are rare in children (around 3–4 in every 10,000 babies are born with cataracts). Cataracts are cloudy patches that develop in the lens of the eye resulting in blurred vision.

If a lazy eye is not treated, it can result in the eye’s central vision never reaching normal levels. An area of the retina called the macula provides our central vision. This straight-ahead vision is the most vital component that allows us to see the world around us clearly.

Good central vision means that we see patterns, shapes, colours and details in a sharp and clear way.

Can having a lazy eye impact someone’s life?

If vision is significantly impaired by having a lazy eye this can make many things in life more difficult, both during childhood and later on. This includes education, playing sports, working and driving.

The younger you are when your lazy eye is diagnosed by a professional, the more likely it is that it can be treated successfully.

• If started after the age of six, treatment is less likely to be successful.
• If started after the age of eight, treatment becomes even less likely to be successful.
• Some promising new research from the USA by the National Eye Institute (NEI) suggests that a lazy eye might now be able to be treated in adolescents up to 17 years of age.

If your child develops a lazy eye that looks different to the norm, or they need to have obvious treatment (such as corrective glasses), they may find that their peers react badly to this.

Aside from having weaker vision and problems with seeing or reading, your child’s life might unfortunately be affected by problems such as:

• Stigma.
• Societal pressures to conform and be ‘normal’.
• Issues around body image/beauty.
• Low self-esteem and low confidence.
• Not fitting in.
• Being bullied for having a lazy eye or for wearing an eye patch or glasses.

It is important that a child with a lazy eye gets medical attention and the opportunity to correct the problem so that they can hopefully have good vision in both of their eyes. It is equally important that all parents and teachers encourage children to be accepting and tolerant of others.

What are the risk factors of a lazy eye?

Some risk factors associated with developing a lazy eye include:

• Family history of having a lazy eye.
• Premature birth.
• Low birth weight/small size at birth.
• Certain developmental disabilities.

You might also be more at risk of developing a lazy eye if you suffer from other vision-related issues, such as a squint, or long- or short–sightedness.

How is a lazy eye diagnosed?

When you have a baby, their vision should be checked during routine tests within their first 72 hours of life. Your baby should receive a second eye exam at 6–8 weeks old.

You can find information about infant and childhood development and milestones in your Personal Child Health Record, usually referred to as your red book. This is the book that you take with you to your midwife appointments and where details of childhood vaccinations are recorded.

Generally, you should notice your child’s vision developing as follows:

• Can follow faces or bright/interesting objects with their eyes by 6–8 weeks old.
• Will show interest in close-by objects by 2–3 months old and make steady eye contact.
• Is able to focus on both near and far objects and shows interest in looking at pictures by 6 months old.
• Can see small objects and recognise familiar faces by 12 months old.

If you are concerned that your baby is not meeting their milestones you should make an appointment with your health visitor or GP to get advice.

Other warning signs you may notice that indicate your infant or child might have a vision problem include:

• Rubbing their eyes when they are not sleepy.
• Being extremely sensitive to light.
• Wandering eyes/eyes that can’t focus or are not well coordinated.

Babies who fail to make eye contact or follow faces with their eyes may have other developmental disabilities or neurodivergence, rather than a vision problem. In all cases, early intervention is key, therefore if you notice anything about your child’s development that concerns you, it is best to speak to a professional.

At your child’s routine two-year check you will have the opportunity to discuss how your child is developing including their height, weight, vision and speech. You can raise concerns during this check-up and arrange for a routine eye test if necessary.

Children under the age of 16 are also entitled to a free NHS eye test. This is something you should take advantage of before they start school (usually around 4–5 years old) even if you do not have any concerns about their vision or development.

An eye specialist or optician should be able to diagnose a lazy eye and advise you on the best course of treatment. Each eye will be covered in turn to see how it reacts to light and stimuli, such as pictures, numbers and letters. The optician may also ask you and your child questions about their vision.

What is the treatment for a lazy eye?

It is important to seek treatment as soon as a problem occurs or if you suspect your child has a lazy eye. This gives the best chance for treatment to be successful and for vision to be saved or improved.

There are two main treatments for a lazy eye:

1. Treating/correcting any underlying issues and eye problems.

2. Encouraging the use of the weaker eye so that vision can develop correctly.

To treat the underlying eye problems, your optician or specialist may recommend:

Glasses – these can be used to correct short- and long-sightedness. Your child might need some encouragement to wear them and to keep them on. For them to be effective, the glasses need to be worn consistently and checked often. Glasses can also be used to straighten a squint.

Surgery – if your child has cataracts, these can be removed under general anaesthetic. Removing the cataracts means that better vision can develop in the eye. Your child will have to stay overnight in the hospital to be monitored post-surgery and aftercare includes administering eye drops regularly.

Surgery can also be effective in correcting a squint. Surgeons will manipulate the muscles and change the position of the lazy eye. Although this procedure alone will not improve vision, it makes the eyes appear more aligned. This can encourage the eyes to start to work together and coordinate the quality of images they send to the brain.

To encourage the use of the lazy eye, your optician or specialist might suggest a number of options, including:

Eye patch – to try to stimulate the weaker eye, your child may be asked to cover their ‘good’ eye with a patch. This is usually a padded white patch with a sticky rim (although you can purchase brightly coloured patches with fun designs to go over this). The patch needs to be worn for at least six hours per day, usually for several months. Eye patches often need to be combined with glasses.

Patches can be very effective in strengthening the lazy eye; however, they may be met with some resistance from the child. This is because you are asking them to cover their good eye and use the eye that they struggle to see properly with. It is important to communicate, in an age-appropriate way, with the child and try to help them to understand the long-term benefit they will get.

The length of time the patch needs to be worn depends on how serious the issue is and the age of the child. They have the highest rate of success in patients below six years of age.

Eye drops – Atropine eye drops can be used to relax the muscles in the stronger eye which in turn blurs the vision in that eye. This forces the lazy eye to work harder. Using eye drops works on the same principle as using an eye patch; vision in the stronger eye is impaired so the lazy eye has to learn to work harder.

The success rates of using eye patches and Atropine eye drops in young children are thought to be similar. Deciding which to opt for may be down to personal preference or which is most practical. Some children may tolerate a patch but refuse the drops or vice-versa.

Sometimes, a lazy eye will not improve despite having treatment.

This might be because:

• It was not diagnosed early enough.
• The treatment was unsuitable.
• The patient did not feel able to persevere with their treatment plan.

In some cases, if less invasive treatment is unsuccessful, surgery may be the only option.

It is important that treatment for a lazy eye is continued as stopping it too soon can mean that any progress is lost. It is also possible for issues to recur, meaning that treatment has to be started again.

With early diagnosis and intervention, it is often possible to improve, if not correct, a lazy eye. If you have any concerns about your child’s vision, health or wellbeing, it is important to speak to a professional who can help you to access the right help for them.