Amblyopia (A Lazy Eye) in children

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What is this information about?

This information answers some of the questions of carers of patients diagnosed with Amblyopia, also called a lazy eye. This includes different ways it is treated. 

Amblyopia (pronounced am-blee-oh-pee-ya) literally means “dimness of vision”.   

What is wrong with my child’s eyes?

Seeing is done not only by the eyes but also by the brain. A picture enters the eye and a signal is sent through a nerve (the optic nerve) at the back of the eye into the brain. This is what we interpret as “vision”.  

In amblyopia the eyes are healthy, but visual information coming from one or both eyes is not clear and is not recognised properly in the brain.

Were they born this way?

Children are not born with perfect vision. This develops over time up until the age of around seven or eight years old.   

For vision to develop normally, the picture coming through the eye and into the brain must be clear so that the brain and the eye can “learn to see”. If it is unclear or missing, then the part of the brain responsible for seeing with that eye will not develop normally. 

If their eyes are healthy then why don’t they see well?

The connections between the eye and the brain which allow us to recognise clear vision need to develop. 

Your child’s eyes and brain are physically healthy, but if a clear picture does not enter their eye, then the cells in their brain cannot grow and develop.   

Why is the picture entering their eye not clear?

There are several reasons that the picture coming through their eye may be unclear and cause amblyopia. The most common are:

• Uncorrected refractive error (need for glasses).
• Strabismus (where the eyes are not pointing in the same direction and not working together)
• Ptosis (a droopy eyelid) 
• A childhood cataract (less common) 

How is their vision affected?

This varies depending upon the cause of the amblyopia and how long the condition has been left untreated. The longer the condition is undetected, the worse the vision is likely to be.

Does it affect both eyes?

Most often amblyopia affects only one eye, but it can affect both, particularly in children who are very long or short-sighted in both eyes.

Can it be treated?

Yes. 

The first line of treatment is to give your child glasses if needed. This will make the picture entering the eyes clear. It can take up to 18 weeks for children to fully adapt to glasses and for some children this is the only treatment.  

If your child does not need glasses or if the amblyopia is still there after your child is fully adapted to their glasses, then the orthoptist will prescribe occlusion treatment. Occlusion treatment is when the better seeing eye is patched, or has drops put in it, so that the vision in the weaker eye gets better.   

If the amblyopia is caused by a cataract or droopy eyelid, then some children may need surgery to remove or reduce this.   

Your child will be seen frequently to make sure that their vision is responding to treatment.

What will happen if no treatment is given?

If treatment is not given before the age of eight then vision loss from amblyopia is likely to be permanent. In some rare cases, it can be treated after the age of eight. 

It is important to carry out the treatment as instructed by the orthoptist and attend appointments so that the treatment can be adjusted according to your child’s progress.  

If you are unable to attend, you must contact the department.  

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