Developmental optometry has lost another giant. Dr. Donald Getz has died. His dear friend and colleague, Dr. Robert Sanet had this to say: “Don loved many things…. he especially loved COVD, where he served as President and Master of Ceremonies at the Awards Banquet, and he loved mentoring optometry students. Don and Lynn opened their home, and Don freely gave enormous amounts of his time and energy to hundreds and hundreds of students who visited him over the years. Don was a great clinician and a tireless champion of behavioral optometry. The impact of his generosity, friendship, and knowledge will be carried on through the lives of the patients whose lives were enriched because of his clinical expertise, and through the amazing optometric knowledge he shared with us.”
Dr. Getz received the Skeffington Award in 1988. I happily re-read his monograph on Strabismus and Amblyopia, which was first published in 1974 by the Optometric Extension Program. In the acknowledgements, he recognizes his vision therapist, Lora McGraw. “She did not have the disadvantage of an optometric education, and, consequently, did not know that certain things were impossible.” Dr. Getz and Lora McGraw were always pushing the envelope and thinking outside the box.
A strabismus is a condition in which the eyes are not aligned. One eye may be turned in (esotropia), out (exotropia), up (hypertropia) or down (hypotropia) relative to the fixating eye. When the eyes are not aligned, this can cause patients to see double. Even worse, overlapping images will cause 2 different objects to appear superimposed on the same location in space. Brains find this “visual confusion” intolerable. In fact, brains will go to great lengths to avoid double vision and visual confusion. Having a strabismus will often cause a series of adaptations to avoid double vision, and perhaps permit the visual system to make the most of a bad situation. These adaptations include amblyopia (reduction in visual acuity and other visual functions), suppression (turning off the visual input from the turned eye), eccentric fixation (using an off- center point on the retina to denote straight ahead) and even anomalous correspondence (remapping the processing of spatial coordinates when both eyes are attempting to work together). It is these adaptations that often make the treatment of a strabismus a difficult task. These adaptations must be eliminated if a patient is going to learn how to straighten their eyes and keep them straight.
In his book, Strabismus and Amblyopia, Dr. Getz explains the importance of tackling these adaptations and then offers many different activities that can be incorporated into a vision therapy program. He places great emphasis on the monocular phase of treatment. If monocular skills are not developed and equalized, binocular therapy will be very difficult; or stated another way, if monocular skills are developed and equalized, binocular therapy will be much easier.
In addition to amblyopia, strabismic eyes have poor spatial localization skills. The brain has learned to interpret straight ahead while the eye is actually turned. This process of locating where objects are, and how far away they are, must be relearned, under monocular conditions. If equal spatial localization exists under monocular conditions, it is almost impossible for the patient to have eccdentric fixation; and if equal spatial localization exists under binocular conditions, it is almost impossible for the patient to have anomalous correspondence.
I have prescribed many of the activities listed in his book as part of a treatment program for amblyopia, but re-reading his book has forced me to reconsider what I am attempting to accomplish. Dr. Getz has reminded me not to overemphasize the visual acuity of the amblyopic eye. Instead, attempt to improve and EQUALIZE the performance of each eye during these activities. The visual acuity will improve along with the improvements in spatial localization and performance. Even if visual acuity is never equalized, the patient may be capable of binocular function. Equalizing the behavior and performance of each eye separately should not be overlooked or rushed in the therapy program for a strabismic patient. The patient will now be ready to match the 2 “ocular circuits” and proceed to the binocular phase of therapy with greater likelihood of success.
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