Vision occurs as collaboration between the eyes and the brain, informed by feedback from the rest of the body. The science of vision therapy is therefore rooted in the ability to guide an individual to make changes through feedback and awareness. As in any effective therapy, there must be a differential diagnostic process identifying which aspects of the visual system are mal-developed or in need of rehabilitation. Intervention can then be designed in accordance with generalized principles of therapy.

Vision Therapy Should Be Individualized and Customized

The science of therapy has established that to be maximally effective, therapy should be individualized and customized to the needs of the patient. Vision therapy may be implemented by a trained therapist, but must be administered under the supervision and guidance of a knowledgeable Doctor of Optometry. The patient must internalize changes and understand that the visual system is modified therapeutically, not by procedures done to the patient, rather to the extent the patient is responsible for viewing differently.

Technology has greatly aided the science of optometric vision therapy but placing the patient in front a computer cannot substitute for active observation and interaction with a therapist. In the next section we review research on vision therapy, but there is one major study that is crucial in understanding the science of vision therapy.

The CITT, or Convergence Insufficiency Treatment Trial, is a multicenter study funded by the National Institutes of Health (the original study name was CIRS, or Convergence Insufficiency and Reading Study). The group that created this study went on to publish the CISS, or Convergence Insufficiency Symptom Survey, to prove that pencil push-up therapy or base-in prism glasses used in isolation were NOT effective, and that home-alone therapy was equivalent to placebo therapy. This is where the science becomes pivotal. Anyone currently treating convergence insufficiency without the benefit of supplemental in-office procedures is essentially dispensing placebo therapy until proven otherwise.