The eyes are responsible for taking in light and sending information to the brain about what they see. The visual system requires communication between the eyes and the nervous system. If the brain stops communicating with one eye, it can begin to move abnormally, resulting in a condition known as amblyopia.
Definition
Amblyopia, which is also known as a lazy eye, is the result of the brain not working properly with one of the eyes, the National Eye Institute explains. If one eye has impaired vision, the brain will tend to ignore the visual signals that it sends. Because the brain is not using that eye, there is also the chance that the brain will stop controlling that eye's movement, causing the eye to no longer coordinate its movements with the other eye.
Causes
The most common cause of amblyopia, according to the Mayo Clinic, is strabismus, which is a condition caused by a problem with the eye muscles. Because the strength of their eye muscles is not balanced, patients with strabismus can develop crossed eyes or eyes that do not move in unison. Extreme near- or far-sightedness can also cause amblyopia. A structural or anatomical problem, such as a cataract or an abnormal retina, can also cause amblyopia to develop. Amblyopia can also be the first symptom of an eye tumor.
Symptoms
Patients with amblyopia, MedlinePlus explains, may have eyes that turn inward or outward. They may also have a problem with depth perception or one eye may appear to be focusing on a different object than the other eye. Patients may also have a tendency to favor one eye or bump it into objects on the same side as the affected eye, the American Optometrist Association explains.
Complications
Amblyopia needs to be treated early in a patient's life, FamilyDoctor.org explains. The parts of the brain that control vision develop early in life, and by the age of 10 most children have completely developed their visual system. If the amblyopia is still present at this point, the vision impairment will continue into adulthood.
Treatment
The treatment of amblyopia involves forcing the brain to use the weaker eye. As the National Eye Institute explains, there are two ways of doing this. Small drops of a medication called atropine can be placed in the stronger eye, blurring the vision and forcing the brain to use signals from the weaker eye. The second approach involves putting a patch over the stronger eye, which forces the brain to use signals from the eye with amblyopia. These treatments should be continued until the vision is fully corrected.
