What is Amblyopia (Lazy Eye)?
Amblyopia, commonly known as lazy eye, is the eye condition noted by reduced vision not correctable by glasses or contact lenses and is not due to any eye disease. The brain, for some reason, does not fully acknowledge the images seen by the amblyopic eye. This almost always affects only one eye but may manifest with reduction of vision in both eyes. It is estimated that three percent of children under six have some form of amblyopia.

Causes of Lazy Eye
Anything that interferes with clear vision in either eye during the critical period (birth to 6 years of age) can cause amblyopia. The most common causes of amblyopia are constant strabismus (constant turn of one eye), anisometropia (different vision/prescriptions in each eye), and/or blockage of an eye due to cataract, trauma, lid droop, etc. 
 
Amblyopia is a neurologically active process. In other words, the loss of vision takes place in the brain. If one eye sees clearly and the other sees a blur, the brain can inhibit (block, ignore, suppress) the eye with the blur. The brain can also suppress one eye to avoid double vision. The inhibition process (suppression) can result in a permanent decrease in the vision in the blurry eye that can not be corrected with glasses, lenses, or lasik surgery.

Detection and Diagnosis of Lazy Eye
An eye exam by a pediatrician or the 20/20 eye chart screening is not adequate for the detection of amblyopia (and other visual conditions). The most important diagnostic tools are the special visual acuity tests other than the 20/20 letter charts currently used by schools, pediatricians and eye doctors. Examination with cycloplegic drops can be necessary to detect this condition in the young.

Since amblyopia usually occurs in one eye only, many parents and children are unaware of the condition. Many children go undiagnosed until they have their eyes examined at the eye doctor's office at a later age. Comprehensive vision evaluations are highly recommended for infants and pre-school children.

Treatment of Amblyopia (Lazy Eye)
Treatment involves dilating drops, vision therapy (binocular therapy) and/or patching.  Recent medical research has proven that amblyopia is successfully treated up to age 17.

Since 1991 our team of trained specialists have been providing accurate, professional diagnoses and state-of-the-art treatment for amblyopia.  We look forward to being of service to you and your family.

Convergence is the coordinated movement and focus of the two eyes inward.  Close work requires the focus both eyes inward on close objects, including books, papers, computer screens, etc. Convergence skills are learned and developed during our early years.

A problem with the coordinated movement of the eyes inward to look at close objects is called a convergence problem. A common convergence problem is Convergence Insufficiency.

When the eyes cannot converge easily and accurately, problems may develop, such as:

• Eye strain
• Headaches
• Double vision
• Difficulty reading and concentrating
• Avoidance of near work
• Poor sports performance
• Dizziness or motion sickness

Treatment of Convergence Problems
Eye coordination problems like Convergence Insufficiency generally cannot be improved with eye glasses or surgery. A program of Vision Therapy may be needed to improve eye coordination abilities and reduce symptoms and discomfort when doing close work.

The 2008 Convergence Insufficiency Treatment Trial clearly supports the superiority of office-based vision therapy to home-based vision therapy alone for Convergence Insufficiency. As noted in the AOA's Clinical Practice Guideline (CPG) on Care of the Patient with Accommodative and Vergence Dysfunction, home-based vision therapy may be less effective than in-office therapy because no trained therapist is available to correct inappropriate procedures.  The preferred clinical management therefore consists of in-office vision therapy supplemented with home therapy.

The Latest Research on Convergence Insufficiency
In October 2008, the National Eye Institute, a division of the National Institutes of Health for the U.S. Department of Health and Human Services, released a statement concerning the effectiveness of office-based vision therapy for treatment of Convergence Insufficiency.   Dr. Mitchell Scheiman, FCOVD, has completed the 12-week study, known as the Convergence Insufficiency Treatment Trial (CITT), found that approximately 75 percent of those who received in-office therapy by a trained therapist plus at-home treatment reported fewer and less severe symptoms related to reading and other near work after the office-based vision therapy.

"This NEI-funded study compared the effectiveness of treatment options for Convergence Insufficiency," said Paul A. Sieving, M.D., Ph.D., director of the NEI.  "The CITT will provide eye care professionals with the research they need to assist children with this condition."

"There are no visible signs of this condition; it can only be detected and diagnosed during a comprehensive eye examination," said principal investigator Mitchell Scheiman, O.D., FCOVD, of Pennsylvania College of Optometry at Salus University near Philadelphia, PA.  "However, as this study shows, once diagnosed, CI can be successfully treated with office-based vision therapy by a trained therapist along with at-home reinforcement."

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.