Lazy eye usually develops from around the age of four. It occurs when there is a reduction in the amount of light entering one eye which results in different qualities of vision, as one is weaker than the other. Over time, the brain may ‘learn’ to ignore images received from the weaker eye and only accept those from the stronger eye.
Why does it happen?
Lazy eye results from other conditions that affect the sight:
- Squint (strabismus): Problems with the eye muscles lead to a misalignment of the eyes.
- Severe long or short-sightedness: An inability for one eye to focus properly can force the stronger eye to work harder, and the other to become ‘lazy’.
- Congenital cataracts: Usually present at birth, congenital cataracts in one eye may make a child’s vision in that eye appear cloudy, forcing the other to work harder.
How to spot it
There are no specific symptoms of lazy eye, but children tend to see less clearly with the affected eye. Parents might notice a child holding his or her head at an angle to see distant objects. Children may repeatedly cover one eye, or develop a habit of squinting.
Lazy eye is usually simple to treat, but it can take time. If unaddressed, the vision may be permanently compromised. Amblyopia can be diagnosed from around the ages of five or six. The underlying problem needs to be addressed – for example, prescription glasses can correct the focus of the weaker eye. The better eye may then need to be covered by a patch for a while, to strengthen the affected eye. Make an appointment with your Optician if you suspect your child has a lazy eye.
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