What is Lazy eye?
Lazy eye, also known as amblyopia occurs when the brain and the eye are not working together resulting in a lack of vision in one eye. This condition occurs in early childhood. The brain focuses more on one eye, virtually ignoring the other, resulting in the lazy eye pointing away from the other. It is usually associated with strabismus, also known as crossed eyes in which a person’s eyes are directed towards two different points. Amblyopia is not a problem in the eye; it is rather a developmental problem in the nerve connecting the eye and the brain.
If the lazy eye is not effectively stimulated, the nerve cells will not mature normally. Lazy eye is usually developed in a child from birth up to 7 years and is one of the major causes of reduced vision in one eye. Very rarely, it is seen that amblyopia affects both the eyes. If diagnosed early, long-term problems can be prevented related to vision can be treated. To correct lazy eye, doctors often prescribe glasses or lenses or eye patches, though in some cases surgery is also recommended.
Lazy eye Symptoms
Sometimes lazy eye cannot be detected without an eye exam, it is therefore essential to get your child’s eye examined periodically. The signs and symptoms are-
- Abnormal results of vision screening tests
- Head tilting
- Shutting an eye or squinting
- Poor depth perception
- Eyes do not appear to work together
- One eye wanders inward or outward
- Eyes pointing in different directions
- Poor vision in one eye
- Significant favoring of one eye
Causes of Lazy eye
It usually starts when one has better focus as compared to the other. At times, one eye has lots of astigmatism or is more farsighted, while the other eye is not. Preexisting eye conditions like refractive problems, ptosis (drooping of upper eyelid) and cataracts or even crossed-eye (strabismus) can result in lazy eyes. In short, it happens when the eyes do not function together or transmit identical images to the brain. It is brain’s natural tendency to ignore the blurry image over the clear one, so if the eye goes on producing blurry images for months or years in a child, the weakened eye will get worse.
The causes of the condition are-
- Deprivation- any problem with an eye like cloudiness in lenses (cataract) can lead to lack of clear vision in a child. It is therefore essential to treat deprivation amblyopia in an infant so that permanent vision loss can be prevented. It often results in a severe amblyopia.
- Refractive anisometropia- the difference in sharpness of vision between the two eyes, maybe because of farsightedness or due to nearsightedness or due to imperfection on the surface of the eye can cause lazy eye. Typically, doctors prescribe glasses or lenses to correct such refractive problems. In some cases, it has been observed that lazy eye is due to refractive problems and strabismus combined.
- Strabismus- imbalance in the muscle is usually the most common cause of amblyopia. It can prevent them from functioning together and can also cause the eyes to turn out or cross in.
Treatment for Lazy eye
- The Glasses- child having farsightedness, nearsightedness or astigmatism are prescribed to wear glasses all the time. It might correct an eye turn or can even solve amblyopia at times. Children often complain that their vision is better without the glasses, but the child should be encouraged to wear them regularly for an effective treatment.
- Correcting droopy eyelids- it usually requires surgery to lift the eyelid.
- Phacoemulsification, or cataract surgery- the cataract is removed surgically under local or general anesthesia.
How to make the lazy eye work?
- Using a patch- a patch is placed over the eye, producing clear image, so that the information from lazy eye is not ignored by the brain. The Patch does not correct the eye turn, but the lazy eye’s vision is improved. The patch must be worn for everyday for a few hours and the child is encouraged to do close-up activities while wearing it like schoolwork, coloring or reading. Specialist determines the length of the treatment based on various factors like the severity of the problem, child’s age and also how much they adhere to the instructions.
- Vision exercises- it involves various games and exercises to improve the vision in the affected eye. Vision exercises along with other treatments are very effective and are helpful for older children.
- Atropine eye drops- the unaffected eye is blurred with atropine eye drops. It is prescribed for children who cannot tolerate wearing a patch. Atropine eye drops dilate the pupil of the unaffected eye, thereby blurring the close up images. This ways the lazy eye is compelled to function more.