Amblyopia, or lazy eye, is poor vision in an eye that failed to develop normal vision during early childhood.
It affects around 2 to 3 percent of people. Someone with amblyopia usually has good vision in one eye, although it is possible for amblyopia to develop in both eyes.
Any condition that impedes the normal development of vision in an eye can cause amblyopia, however the two most likely causes are:
- Strabismus (misaligned or crossed eyes) – A misaligned or crossed eye will eventually turn-off to avoid double vision occurring. This will prevent vision from developing normally and amblyopia will result.
- Unequal Focusing – Amblyopia can occur in an eye that has poorer focusing than the other eye due to refractive error. This can be difficult to detect as there is no visible symptom like in the case of a crossed eye.
- Non-refractive Amblyopia – May occur in the absence of poor focusing or an eye turn yet one or both of the eyes may have blurred vision. This is commonly associated with some form of congenital developmental delay, or may be associated with an eye injury or brain injury.
Amblyopia may also develop in an eye that has become cloudy in the areas of tissue that are normally clear. An example of that is Cataracts.
Where a child has high levels of long sightedness, shortsightedness or astigmatism, amblyopia may develop in both eyes.
Because amblyopia is not easily detectable in infants, a routine eye examination by an optometrist is recommended for all small children. The earlier amblyopia is diagnosed, the more effective the treatment will be.
Ideally, treatment for amblyopia should begin in infancy or early childhood.
Amblyopia is treated by wearing glasses to improve the vision in the poor eye, thus allowing the vision to develop normally. In some cases the good eye may be blurred with the use of glasses or a patch to encourage the poorer eye to work. Vision Therapy is often very effective in the treatment of amblyopia, this involves a customised program of activities conducted both in-office and at home in order to stimulate the visual system and enhance binocular vision ability.
Success in treating amblyopia depends on how severe it is and how early it’s detected. Early detection and treatment of amblyopia will mostly result in improved vision.