What is accommodative esotropia?
Accommodative esotropia refers to eye crossing that is caused by the focusing efforts of the eyes as they try to see clearly. Patients with refractive esotropia are typically farsighted (hyperopic). This means that the eyes must work harder to see clearly, particularly when the object of regard is up close. This focusing effort is called accommodation. The closer an object is to the eye, the greater the amount of accommodation that is required. A side effect of the accommodative effort can be excess convergence or crossing of the eyes.
Why is accommodative esotropia a concern in children?
If a child’s eyes cross at an early age, then vision will not develop normally. Vision can be permanently reduced in one eye if it is not “used” properly causing amblyopia. If crossing of the eyes is diagnosed and treated early, then vision development can proceed normally. Crossing of the eyes is never normal (except for occasional crossing in the first three months of life), and any child suspected of having crossed eyes should be examined by a child eye specialist/ child eye doctor.
Do all children with farsightedness have accommodative esotropia?
No. The more farsighted a person is, however, the greater the amount of effort they must exert and the more likely they are to cross their eyes. Therefore, while two individuals may have the same glass prescription, one may have eye crossing and the other may have perfectly straight eyes. Heredity plays a role in determining which children develop squint/ esotropia.
How is accommodative esotropia treated?
Initial treatment for accommodative esotropia usually involves the prescription of eyeglases to correct the refractive error. This will reduce the convergence or crossing stimulus and the eyes will straighten as they relax. Glasses should be worn full time.
Does surgery play a role in accommodative esotropia?
Surgery is indicated only if the eyeglasses fail to straighten the eyes adequately while the glasses are on. In this case, squint surgery (strabismus surgery) may be recommended to help improve the alignment of the eyes. The surgery is usually done in childhood to help promote binocular vision development. Surgery for accommodative esotropia does not eliminate the need of glasses, but corrects the amount of squints leftover when the glasses are on. The eyes will likely continue to cross when the glasses are off and surgery does not replace the need for glasses.
Why do some children with accommodative esotropia require bifocals?
In some cases, children will have particularly excessive amounts of eye crossing (esotropia) when looking at objects up close, such as while reading. This may occur even when wearing the correct glasses to correct their farsightedness (hyperopia) and they may have perfectly straight eyes when looking at objects further away. These children may benefit from making the lower, reading area of the eyeglasses “extra strong” in the form of a bifocal lens.
Can children outgrow accommodative esotropia?
Yes, children can outgrow accommodative esotropia. This usually happens during adolescent years as a child becomes less farsighted. It is difficult to predict early in childhood whether or not any given child will outgrow their need for glasses.