The term amblyopia refers to a condition that is characterized by a dimness of vision, and is directly related to eye development. This eye condition (which is also known as lazy eye) is not known to be relieved by glasses. Also, no physical abnormalities are evident in the eyes even when examined.
There are two principal types of amblyopia. The first type includes those in which the affected individual has subconsciously trained himself to ignore the vision of one eye. The second type includes those in which there has been toxic or chemical damage to the optic nerve.
In one classic example of the first type, a young child who has a walleye (the eye’s axis diverges) or a crossed eye (the axis of one eye crosses with the other’s) often ignores the vision of one eye in order to avoid double vision. In another example, one form of hysteria – called conversion disorder – may cause the person to actually believe he is blind despite his eyes being normal. In both examples, amblyopia is certain to develop.
In the case of the second type, toxic amblyopia may result from excessive use of tobacco or alcohol. It may also follow exposure to carbonic oxide (or carbon monoxide), methanol (wood alcohol), tetrachloromethane (carbon tet), benzene, or lead or arsenic compounds. In some cases, amblyopia may occur and later disappear in multiple sclerosis. It may likewise occur in the condition that often accompanies kidney failure, called uremia, and then disappears once the patient recovers from this condition.
Among the symptoms first experienced by the individual affected with toxic amblyopia is that of having foggy vision. Later, there is central blind spot that grows larger as the eye condition progresses. Treatment for toxic amblyopia associated with exposure to chemicals such as those mentioned above involves seeking out the actual cause and removing it. Recovery can be greatly helped with the administration of vitamin B complex.
A child with a walleye or a crossed eye should be placed under a special treatment program before he or she develops a permanent habit of ignoring the vision of one of his/her eyes. The parents should not wait to see if their child will outgrow the condition; instead, they should consult an optometrist immediately.
For cases resulting from conversion disorder, treatment should be directed to the cause of the disorder.
Amblyopia of any cause can be corrected by surgery. The eye physician may recommend certain exercises before or after such surgery.
1. “Amblyopia (Lazy Eye),” on Prevent Blindness America (online) – http://www.preventblindness.org/children/amblyopiaFAQ.html
2. “All About Amblyopia (lazy eye)” by Dr. Jeffrey Cooper and Rachel Cooper, on Optometrists Network (online) – http://www.strabismus.org/amblyopia_lazy_eye.html