What is Amblyopia (Lazy Eye)?
An amblyopia is a type of poor vision which occurs in one eye but less frequently in both eyes. The condition occurs when the brain and the eye fail to work together properly, and the brain cannot recognize sight from one eye. The weaker eye’s vision becomes increasingly blurry over time as the brain relies increasingly on the stronger eye.
Amblyopia is often called a lazy eye, because it is easier for the stronger eye to see. However, people with amblyopia are not lazy, and they cannot control the way their eyes see.
Up to 3 out of 100 children have amblyopia, which causes vision loss in their childhood. The good news is that early treatment usually prevents long-term vision problems.
What are the symptoms of amblyopia?
It is often difficult to detect the symptoms of amblyopia in children. Children with amblyopia often have poor depth perception, making it difficult to determine how far or near something is. Parents may also notice that their child is unable to see clearly, such as:
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Eyes squinting
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Shutting one eye
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Tilting their head
Most parents are not aware that their child has amblyopia until a doctor diagnoses it during an eye examination. That’s why it is important for every child between the ages of 3 and 5 to get a vision screening.
Is my child at risk for amblyopia?
Amblyopia occurs in some children at birth and in others later in childhood. The likelihood of developing amblyopia is higher for children who:
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Premature birth (early birth)
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At birth, they were smaller than average
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Have a history of amblyopia, childhood cataracts, or other eye conditions in your family
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Having developmental disabilities
Amblyopia: what causes it?
Generally, doctors are unable to determine the cause of amblyopia. But in some cases, an amblyopia may be caused by another vision problem.
As a rule, the brain relies on nerve signals from both eyes to perceive images. However, if one eye has severe vision problems, the brain may try to avoid this situation by turning off signals from the weaker eye and relying only on the stronger eye.
Amblyopia can be caused by the following eye conditions:
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The refractive errors are usually associated with nearsightedness, farsightedness, or astigmatism, which results in blurry vision. Normally, these problems can be easily corrected with glasses or contacts. If they are not corrected, the brain may be reliant on the eye that has greater vision in the future.
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There is a condition known as Strabismus in which the eyes do not line up when moving together. In children with strabismus, one eye may drift inwards, outwards, upwards, or downwards.
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Cataracts affect the lens of the eye, causing things to appear blurry. Although cataracts usually affect older individuals, they can also occur in babies and children.
How will my child’s doctor check for amblyopia?
The doctor will check for signs of amblyopia as part of a routine vision screening. Children between the ages of 3 and 5 should have their vision checked at least once each year.
What’s the treatment for amblyopia?
It is possible for the doctor to recommend eyeglasses or contacts first (for children who are nearsighted or farsighted) or surgery (for children who have cataracts) when there is a vision problem causing amblyopia.
Next, the brain must be re-trained to use the weaker eye. As the brain uses the weaker eye more, it becomes stronger. Treatments include:
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Wearing an eye patch over the stronger eye. When the stronger eye is covered with a stick-on patch (similar to a Band-Aid), the brain must use the weaker eye to see. Some children need the patch for only two hours a day, while others may need to wear it continuously.
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Using special eye drops in the stronger eye. Once a day, the drug atropine can temporarily blur near vision, forcing the brain to use the other eye. A treatment such as this is as effective for some children as an eye patch, and some parents find it easier to use (for example, due to the possibility that young children may try to remove eye patches).
In the beginning, your child’s vision may begin to improve within a few weeks, but it will probably take months to achieve the best results. After receiving these treatments, your child may still need to use them from time to time to prevent amblyopia from returning.
Children with amblyopia should be treated as early as possible – the sooner the better. Children who do not receive treatment grow up to have lifelong vision problems. The treatment for amblyopia is less effective in adults than it is in children.
