Amblyopia

Amblyopia or lazy eye condition is when one eye fails to develop as the other. The condition starts in childhood and is a significant cause of vision loss in children. In contrast to different vision problems, there is an issue with only one eye in amblyopia. Just one eye may have an issue connecting with the brain. The brain cannot recognise the signals from one eye and starts depending on the other one every time. As a result, the functional eye works around the clock, exhausting all its strength. Thus, the eye with poor vision gets the name lazy eye! But on the bright side, amblyopia is treatable, and the earlier it is diagnosed, the easier it is to prevent long-term vision loss.

The primary cause of amblyopia is the difference in eyesight between the two eyes. When one eye falls short of focussing, the other eye tries to make up for it. Therefore, various eye disorders may lead to amblyopia or lazy eye.

Some of the disorders that may lead to amblyopia if left untreated are:

1. Astigmatism – a condition where the cornea is curved
2. Near-sightedness (myopia) – difficulty seeing the objects far away
3. Far-sightedness (hyperopia) – difficulty seeing the objects nearby
4. Crossed eyes (strabismus) – a condition where the two eyes have difficulty moving together as a pair
5. Problems with the structure of the eyes 
   1. Childhood cataracts (blurry vision due to cloudiness in the lens)
   2. Droopy eyelid
   3. Corneal scar

Risk Factors:

As amblyopia or lazy eye is a disorder of childhood, the risk factors are mainly related to familial genes or are birth-related like:

1. Developmental disabilities or childhood cataracts
2. Premature birth (children who are born earlier than their due date)
3. Children who were smaller than average at birth
4. Family history of eye disorders

The key to preventing the worsening of amblyopia is to catch it at an early stage, although the symptoms are difficult to notice. Therefore, the adults must try to be observant around the children.[1,2] Some of the signs your child may exhibit if they have difficulty seeing things are:

1. Difficulty perceiving the depth 
2. Difficulty understanding how far or near an object is
3. Having crossed eyes or droopy eyelids
4. Frequent squinting
5. Closing one eye to focus with the other eye
6. Tilting their head to one side frequently
7. Bumping into things on one side, particularly
8. Preferring one side of the body over the other

Amblyopia or lazy eye is diagnosed by a comprehensive eye examination, which tests the following aspects:

1. Are the eyes moving together and correctly?
2. Does the vision differ between the two eyes?
3. How well can the two eyes see? 
4. How is the alignment of the eyes?
5. Is one eye moving separately or drifting?
6. Are there any structural problems in the eyes, such as cataracts?

The ophthalmologist or the child’s paediatrician may examine the eyes by the following steps. They will:

1. Apply eye drops to widen the pupil of the eye 
2. Shine a small light on each eye to view its inner parts
3. Cover one eye of the child and move an object around the eyes and ask the child to follow it with their open eye
4. Repeat this for both the eyes
5. Ask the child to read the alphabet or numbers on a chart put up on the other end of the room (if the child is old enough to read)

Now that we have discussed all the causes and symptoms of amblyopia. Let us explore the treatment options for the same. The treatments for the disorder are as follows:

1. Eye patches for children: The disorder results from the lack of coordination between a weak eye and the brain. Therefore, the primary treatment method may involve putting an eye patch on the better eye for a couple of hours each day. This way, the brain is compelled to use the images from the weaker eye, making it coordinate well with the brain.[1,2]
2. Eye drops: An alternative to an eye patch for milder cases is the application of eye drops containing atropine that blurs the vision of the better eye. Your doctor may ask you to apply the drops to the eye with better vision every day. This will temporarily make the better eye blur for a few hours and force the brain to use the weaker eye. This method also works the same way as the eye patch.
3. Eyeglasses: In certain cases, eyeglasses that correct near-sightedness, far-sightedness, and astigmatism may correct amblyopia, thus, slowing the progression of amblyopia.

The benefits of treating amblyopia are:

1. Diagnosing and treating amblyopia early significantly improves the vision.
2. It also prevents the permanent loss of vision.

Amblyopia or lazy eye will not resolve on its own. Hence, the adults (parents) must pay attention to details. Treating lazy eyes in a teenager or an adult is challenging. If the condition is left untreated, it may cause:

1. Permanent loss of vision 
2. A ‘’wonky eye’’ is an eye that always faces the other direction