Sunday, October 28, 2012

Alternatives to strabismus surgery - vision therapy is 87% effective

Vancouver's children's optometrist -Vision therapy for strabismus is an alternative to surgery

Under optimal clinical conditions the success rate for vision therapy treatment of strabismus is 87%

Vision therapy/orthoptics has been used to successfully treat the various forms of strabismus for over 100 years. Numerous studies have found it to have a 75% success rate in achieving normal cosmetic alignment of the eyes as well as functional binocular vision.  Under optimal clinical conditions such as those in a private practice optometric clinic where each patients receives individualized, one-on-one care, the success rate can be as high as 87%.

The Ludlam Study on Vision therapy for strabismus

Dr. William Ludlam conducted a landmark study, but not the first such study, of 149 strabismus patients who came for treatment at the Optometric Centre of New York.  Ludlam summarized the results as follows: 

"combining the functional and almost cured groups and adding four patients whose eyes ware straight ... but are listed as 'moderately improved' because of the the technical requirements of the 'cured' categories (2 subnormal ranges of motor fusion, 1 with a 7" N.P.C. rather than the required 4", and 1 with frequent asthenopia, headaches and accomodative spasm), we may state that a total of 113 (76%) of the patients in the sample had binocular vision with straight eyes 95% of the time or more at dismissal from teh regular clinic training sessions. The other 36 patients had residual deviations occurring more often than 5% of the time, and were classified as orthoptic failures. Of these, 8 of the "moderate improvement" group dropped out when quite near the "almost cured" category, i.e. with their eyes straight well over half the time and possessing all of the technical factors necessary for a cure with several moths of additional stabilization work."

Even though the Ludlam study produced outstanding results, Ludlam pointed out that the patients treated at the Optometric Centre were treated in poor clinical conditions. For example, they received group therapy, control and management of each case was relatively poor, and they were treated by different clinicians who had diferent personalities and treatment approaches.  He expected that under the optimal conditions of a private practice optometric office, the results would be even better.  Indeed, subsequent studies shown this to be the case.   Click here to read more about the Ludlam study.

The Hoffman & Allen Study on vision therapy for strabismus

Another significant study addressed Ludlam's expectation that optimal clinical conditions would produce better results.  The study, by Hoffman, Cohen, et al., found that the vision therapy treatment fo strabismus had an 87% success rate in clinical circumstances that were "near optimal" such as those conditions that obtain at a private practice optometric clinic.  The researchers also found that younger patients were easier to treat than older ones and that exotropes (patients whose eye turns outwards towards the wall) were easier to treat than esotropes (patients whose eye turns inwards towards to nose) .  Even so, the vision therapy treatment of esotropes achieved a very impressive success rate of 74.5%.  Moreover, the maximum success rate of 100% was obtained in treating intermittent and periodic eye turns whereas constant eye turns were treated at a still-impressive success rate of 76%.

Case Reports on vision therapy for strabismus

Numerous case reports have been published documenting the treatment of strabismus patients with vision therapy.  The most recent was published in August 2011 in the journal Optometry by Peddle and Steiner who discussed two cases of adults with moderate sized intermittent exotropia (eyes turned outward to the wall). Both patients also had asthenopia (eye fatigue and discomfort), headaches, and/or diplopia (double vision). Twenty to 30 in-office VT sessions were recommended to reduce the magnitude and frequency of the deviation as well as improve their binocularity and decrease their symptoms. After completing VT, both patients became phoric for all distances, had normal vergence ability, and had normal near points of convergence.

The most famous case of vision therapy treatment for strabismus

In an inspirational book called Fixing My Gaze, neuroscientist, Susan Barry, who was born with strabismus and had lived all her life without depth perception as a consequence, meaning that she could not see in three dimensions.  The book was's number 4 science book of 2009.

She had three surgeries to "correct" the eye turn cosmetically but she still could not see properly and the eye was still turned, although less than before. She had lived this way for over 40 years until she met optometrist Dr. Theresa Ruggiero.

Dr. Ruggiero treated Susan with vision therapy and corrected the eye turn and allowed her see in three dimensions for the first time in her life. Can you imaging how her world was transformed? I've heard rumors of a "Fixing My Gaze" movie but have not been able to confirm them.

Doctor Barry has received much attention for her book and her experience with vision therapy.  She has been interviewed for numerous publications and her story was the subject of a feature article in the New Yorker.  

You can visit Susan Barry's website here.  Here are some videos of Susan Barry talking about vision therapy and strabismus:

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