What is Amblyopia?

Amblyopia, also called as lazy eye is when the eye is not able to see normally. The vision may be good in one and poor in another or this condition may rarely occur in both the eyes.

As Amblyopia usually sets in very gradually, children often get used to it. Also when the child is using both their eyes, the faulty vision may not be apparent. Hence they may not complain about it to their parents resulting in a delay in diagnosis for months or even years. Also the child may be unaware that the vision in one eye can be better than what he/she is perceiving.

What causes Amblyopia?

In the first few years of life, a child’s brain learns to “see” the images provided by the eyes. Part of this involves recognizing the two images received from both our eyes and helping us see one comprehensive image. If due to any of the below reasons, the brain receives a poor image from one eye, it learns to ignore the image from the defective eye to ensure that we continue to see well. Without treatment, this could gradually lead to a situation where the brain learns to permanently turn off the faulty images from the weaker eye leading to permanent vision issues.

Any eye condition that blurs vision can be a cause of Amblyopia. A few examples are given below:

• Refractive Errors / Spectacle powers: One eye may provide a better focused image to the brain if there is a significant difference in spectacle powers due to near or far sightedness or astigmatism (uneven surface curve).
• Squint / Strabismus: Sometimes, the two eyes don’t align properly due to one eye turning inwards, outwards, upwards or downwards. The brain is then forced to shut out the image from the misaligned eye so as to avoid seeing double.
• Cataract: A cloudy lens inside one eye results in one eye sending a blurry image to the brain.
• Droopy Eyelid / Ptosis: A drooping eyelid can block the vision of an eye.

What are the risk factors for Amblyopia?

A child is at a higher risk of developing lazy eye if the below conditions exist:

• Premature birth
• Family History of amblyopia or other eye conditions
• Child is smaller than average at birth
• Developmental Disabilities

What are the signs and symptoms of Amblyopia?

Lazy eye can begin as early as 3 months of age if the visual input from both the eyes is not normal.

Many times, there may be no obvious signs and the amblyopia may not be evident without an eye test.

• One may notice that the child tilts their head or adopts an abnormal head position to see better.
• The child may squint or shut one eye while focusing on an object.
• There may be difficulties with perceiving depth.
• Symptoms of the eye condition that is causing the amblyopia may be seen like a wandering eye

How is Amblyopia tested?

A child eye doctor tests for Amblyopia by checking to see if vision is different in both the eyes. This can be done even in very young children by covering one eye and testing for vision in the other.

A complete eye exam will reveal the cause of amblyopia.

How can Amblyopia be treated?

The first step is to treat the eye condition that is causing amblyopia. Glasses for near or farsighted and surgery for squint or cataract may be advised.

The next step is to re-wire and force the brain to use the weaker eye. This is done by removing any possibility of the brain to lean on the stronger eye to get the correct images. This can be done by:

• Wearing eye patch on the stronger eye.
• Putting in special eye drops (atropine) to temporarily blur the vision of the stronger eye.
• Neuroadaptive therapy using specific computer programmes like dichoptic exercises

An important thing to remember is that early treatment usually works well. If the lazy eye is not treated for years, the vision loss may be permanent. Amblyopia treatment in kids works much better than it does in adults. It usually takes a few months to get good results. Even after that, the child may need to use the drops / patches intermittently to prevent the amblyopia from returning.

How can Amblyopia be prevented?

The easiest way to prevent Amblyopia is to catch any eye condition before it goes on to produce marked symptoms or damage. This is why regular eye check ups are important even if the child has no complaints.  We recommend an eye check up at 1 year, 3 years and 5 years of age even in absence of any eye complaints for any child.