What is "lazy eye"?

What is "lazy eye"? Many of our patients will refer to lazy eye as a condition when the eyes are not straight. The two medical terms which best describe the condition are strabismus and amblyopia. Children often appear to have "crossed eyes" when they are young.  Strabismus refers to the misalignment of the eyes. They can be be misaligned or turned in different ways, but crossing inward (esotropia) or outward (exotropia) are two of the most common problems. If one or both of the eyes have decreased vision due to strabismus, we often call this amblyopia.
 
Many children will prefer vision from one eye. They may cross one eye nasally and the other eye may remain straight. The brain compensates by ignoring the crossed eye. If this occurs over time,  the brain does not learn to "see" with the crossed eye which could result in permanent decreased vision. If diagnosed early, treatments are available which can help restore the vision.  Many children may need glasses to correct any refractive error and patching of the good or straight eye to "teach" the crossed to see better. Patching typically does not work after age 8. Some children could have straight eyes but one of the eyes being significantly more farsighted and the brain could learn to ignore the farsighted eye resulting in amblyopia. These are more difficult cases because the eyes look normal to the parents and the child often
doesn't have any complaints.  This is why we strongly recommend a baseline eye examination around age 5 to be certain the eyes are healthy and each eye has good vision.
 
There are many different types of strabismus and ocular misalignments which are well beyond the scope of this blog. Interestingly, there are entire books just on this topic alone. If your child appears to have crossed eyes or any eye problem, have them evaluated promptly. If your child has no apparent eye problems,  the start of kindergarten is a great time to get a baseline exam. Remember, protect those eyes!!