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MBKU receives $228,093 from National Eye Institute for “Convergence Insufficiency Treatment Trial"


Convergence insufficiency is a common childhood eye-teaming problem that affects about 5 out of every 100 children. This visual disorder causes the eyes to have a strong tendency to drift outward when reading or doing work close up. Double vision often occurs if an eye drifts out. To avoid seeing double, a child with CI must use extra effort to make the eyes turn back in. This extra effort can lead to exasperating symptoms, such as eye strain, blurred or double vision, loss of concentration, and frequent loss of place when reading and working up close.

“It is well documented that children with symptomatic CI report significantly more symptoms when reading and doing close work (e.g., blurred vision, headaches, double vision, loss of concentration, frequent loss of place, trouble remembering what was read), manifest more academic-impairing behaviors (e.g., difficulty finishing assignments) and score worse on parent ratings of attention compared to children with normal binocular vision,” said Susan Cotter, O.D., M.S., Professor of Optometry at Marshall B. Ketchum University’s Southern California College of Optometry. “Because reduction of symptoms and adverse academic behaviors are associated with the successful treatment of CI, we have proposed to test the hypothesis that resolution of these symptoms and behaviors leads to improved reading performance and attention. To definitively determine whether the successful treatment of symptomatic CI positively impacts reading and attention requires a large-scale placebo-controlled randomized clinical trial.”

The results of this trial will have significant impact on the scientific knowledge about the relation between the treatment of symptomatic CI in children and its immediate effect on reading performance and attention and the long-term effect one year post treatment. If the study demonstrates that the successful treatment of CI does not have a beneficial effect on reading performance and attention, professionals and families will know that CI therapy only improves visual signs and symptoms. If the evidence supports a positive relationship, professionals and families will know that CI treatment may improve reading performance and attention as well as visual signs and symptoms. Investigators then will have a new approach for posing questions to tease out the neural and other systems that drive and explain these relations.

“Considerable resources are expended on an annual basis by optometrists and ophthalmologists in writing position papers and practice guidelines addressing the relationship between visual disorders and reading. Currently, there is no solid evidence-base to support any opinion and we hope to change that,” stated University President, Kevin Alexander, O.D., Ph.D.

The second year of study recruitment begins on September 1, 2015. Of the eight clinical sites (others located in Akron, Birmingham, Columbus, Ft. Lauderdale, Miami, New York City and Philadelphia), the Southern California College of Optometry site was the top recruiting site last year. Those interested in the study or who desire further information can consult the study website at or contact Dr. Cotter at