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; STRABISMUS IS A "BRAIN" PROBLEM. The condition usually develops before a child is two but can occur as late as age six. It is important that strabismus receive prompt treatment. Children do not outgrow crossed eyes, and the condition can worsen over time. Children with strabismus may develop additional complications with amblyopia, or "lazy" eye. (Note: It is common to see infants younger than three months cross their eyes as they are learning how to team and coordinate their eye movements. This is normal and not a condition of true crossed eyes.)
Characteristics of Strabismus:
The eye can go "in" toward the nose.
It can go "out" from the nose.
It can happen part time or all the time.
It can be either eye.
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. Their 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.
Older children and adults can develop a crossed eye after a head injury, stroke, or as the result of some diseases. When this happens and the onset of strabismus is later in life, these older children and adults will usually experience double vision.
Glasses can help relax the crossed eye that is turning in too far, allowing it to aim straighter. In very mild cases of crossed eyes this may be enough to correct the problem, but usually additional treatment is required. There are two different approaches to the treatment of strabismus: surgery and therapy.
The Surgery Myth
Ophthalmologists, or eye surgeons, usually recommend surgery to correct strabismus. In the US, our surgeons recommend surgery 10X more often than in most developed countries.
Parents often don't understand about eye surgery. One example: that strabismus is caused by "weak" eye muscles. Not true, but it's an easy way for doctors to explain the problem. The problem is not muscular, but in the brain. Strabismus is the result of faulty coordination between the brain and eye muscles--in other words, strabismus is a brain-based problem.
A simple procedure can show this. Place your finger in front of the child and have him look at it. Now cover the straight eye with your other hand and watch the crossed eye. It immediately straightens. The muscles in the crossed eye automatically aim the eye without difficulty. The real problem is not weak muscles, but the inability of the brain to control the muscles in both eyes at the same time--in other words, faulty signals from the brain to the two eyes.
The need for surgery is often oversimplified, such as "the weak eye muscles must be operated upon to realign the eye and correct the problem." There are two large problems with this:
1) Since weak muscles aren't the cause of strabismus, then surgical intervention is addressing only a symptom, not the cause.
2) In the vast majority of cases, surgery does not "correct" the child's inability to use both two eyes together; it only aligns the eyes so they look straight.
If you don't need eye surgery, you should see a non-surgical specialist (board certified optometrist) to be properly evaluated.
The long term restoring of function that you want for your child with a crossed eye is the goal of non surgical treatment (vision therapy).
Ophthalmologists consider a surgery "successful" if afterwards the eyes look straight. Why? Because surgery rarely improves visual function. What is visual function? It includes, among other things, the ability to see fully in 3D. Surgery deals only with muscles, not the brain. It does nothing to train the brain how to use both eyes together. Instead, the process of invasive surgery and resulting scar tissue only compounds the real problem, making later nonsurgical intervention much more difficult.
Less than 20% of children who undergo one eye surgery alone for a crossed eye eventually achieve binocular fusion (two-eyed vision) with normal depth perception and visual function.
Over 80% of surgery patients still live in a one-eyed world without depth and distance judgments.
Unfortunately, if the eye looks straight after surgery, most parents do not realize their child's overall vision hasn't improved at all. And because the real cause of strabismus was not addressed, the cosmetic results of surgery are often not permanent. Over time, the eye begins to turn again and repeated operations are required to realign the eye.
There is a better way.
Unlike surgery, vision therapy addresses the cause of strabismus. Therapy teaches your child a new way to see. It corrects the problem 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 that are straight and a visual system which operates normally. Most importantly, because binocular fusion (two-eyed vision) is the "glue" which holds the eyes straight, the results are permanent.
Why, then, when therapy is so effective in curing strabismus is surgery so often recommended? Part of the answer lies in the "David and Goliath" syndrome. Their job is to perform surgery.
However, 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 operating on the eyes to make them appear straight. (This is not true in Europe. European ophthalmologists have much more extensive training in functional vision training, and therapy is nearly always recommended before surgery.)
The number of American doctors specializing in vision therapy, on the other hand, is small, but growing. There are less than 600 board certified developmental optometrists specializing in vision therapy. These doctors are Fellows in the College of Optometrists in Vision Development, the national certifying organization for doctors who specialize in vision therapy. All Fellows have passed a rigorous national board to receive their certification in the remediation of binocular vision problems. Because of their training and background, C.O.V.D. Fellows are functional vision specialists with the knowledge and expertise to fully correct strabismus. But because their numbers are so much smaller nationwide, so is their patient base.
One of the reasons that there are fewer eye doctors specializing is vision therapy is time. Therapy takes longer. It's worth it.
In the end, you have to decide what is right for your child. We pride ourselves on offering true, scientific information for you so you can make an informed decision. If your child has strabismus, the best advice is to educate yourself on the pros and cons of each option. Make an appointment with a developmental optometrist who provides vision therapy. 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 you get all your questions answered by the doctor? In the end, parents must make an informed decision, based on facts.