Strabismus, commonly referred to as "crossed" or "wandering eyes", occurs when one or both eyes turns in or out, up or down.
The condition is caused by the brain's inability to coordinate both eyes simultaneously. The brain is the master control center of vision, and somewhere early in a child's vision development, the brain failed to develop "binocularity," or the ability to use both eyes at the same time. It is important that strabismus receive prompt treatment. Children do not outgrow crossed eyes, and the condition can worsen over time.
Because the brain has not learned to align the eyes and use them together, each eye aims independently of the other. In other words, both eyes do not point at the same place at the same time. When each eye is looking at a different place, the brain receives two different "pictures". This would normally result in double vision. However, these children's brains learn to protect themselves from seeing double by suppressing, or "turning off" the crossed eye. The brain refuses to receive the visual input from the turned eye; children with a crossed or wandering eye only see out of one eye at a time.
Ophthalmologists, or eye surgeons, usually recommend surgery to correct strabismus. However, strabismus surgery has some very real limitations. It will improve the eye's appearance, but rarely does it do anything to improve vision. The situation cannot be overstated: surgery for crossed or wandering eyes is primarily a cosmetic consideration with little or no affect on the eye's visual function. In fact, the nerve damage and scar tissue that result may permanently reduce the child's chances of achieving normal two-eyed vision later on through therapeutic remediation.
Your brain directs and controls your eyes and eye muscle surgery is not brain surgery. Cutting and moving the eye muscles will not automatically change the brain or the signals it sends to the eye muscles. This is why patients' eyes often "go back" or deviate again after surgery. Frequently, then, the surgeon recommends a repeat surgery. It is important to understand what while eye muscle surgery can improve cosmetic apearance, it does not necessarily improve eyesight or vision. If your surgeon has recommended initial eye muscle surgery, ask how many surgeries may be possible. The surgeon should be very clear as to the possibility that repeat surgeries will be recommended down the road.
Most children who have undergone surgery for a crossed eye still suppress one eye full time. Suppression is the brain's learned response to avoid double vision. Suppression must be unlearned and the brain trained to use both eyes together if normal functional vision is to be restored. Less than 20% of children who undergo eye surgery for a crossed eye eventually achieve binocular fusion (two-eyed vision) with normal depth perception and visual function. The few who do are nearly always very young children whose visual systems were still devleoping and fluid enough to fall into binocularity on their own. This is not true for the vast majority, however. Over 80% of surgery patients still live in a monocular,one-eyed world without depth and distance judgments. In fact, new research shows the eye muscles' sense of where the eye is pointed (propriocetion) is destroyed if surgically altered and never formed if operated on before the age of 5. So, surgery may do some harm.
Unlike surgery, binocular therapy and visual integration addresses the real cause of strabismus. Therapy improves the coordination between the brain and eyes, eliminates suppression, and teaches the brain how to use both eyes together so that the eyes remain straight. By treating the underlying cause of strabismus, binocular therapy restores normal vision. Therapy corrects the child's vision system by teaching the eyes how to aim together and training the brain to receive and fuse the visual images from both eyes at the same time. Ninety percent (90%) of therapy patients complete treatment with eyes which are straight and a visual system which operates normally.
American ophthalmologists have no training in vision therapy and have only a very limited knowledge in functional vision remediation. When it comes to strabismus, the only treatment that ophthalmologists have with their surgical background is to operate on the eyes to make them appear straight. This is not true in Europe. European ophthalmologists have much more training in functional vision training, and therapy is nearly always recommended with surgery.
A surgeon might have told you that surgery is the only option. However, in the First Quarter, 2002 issue of the Binocular Vision and Strabismus Quarterly, the Journal editor, Paul E. Romano, M.D. stated, "I simply do not believe the current organized ophthalmology - pediatric ophthalmology mantra that virtually nothing with regard to binocular (two-eyed) vision (except maybe convergence insufficiency) can be affected, altered or improved by anything other than surgery. There are too many other areas in medicine where change is achieved without drugs and surgery."
Surgery, if necessary, should be coordinated with a developmental optometrist who is knowledgable in visual development if the goal is for improved vision or binocular vision. During the critical period, if therapy is not initiated immediately following surgery, the chances of success dimish. Pre-surgical consultation and therapy are also helpful.
If your child has strabismus, the best advice is to educate yourself on the pros and cons of each option. Make an appointment with both a surgical ophthalmologist and a developmental optometrist who provides binocular therapy and visual integration. Be proactive. Ask questions. Does what you've been told make sense? Does it seem reasonable? What are the risks of the treatment being proposed? Did the doctor answer all of your questions? In the end, parents must make an informed decision about which type of treatment option they will pursue.