National Eye Institute study identifies vision therapy as the most effective treatment for convergence insufficiency


Problems with learning and reading are often cause by vission disorders.


Convergence insufficiency is one of the most common vision disorders that interferes with reading. It was recently the focus of a scientific study in the United States funded by the National Institutes of Health and the National Eye Institute - the study found that vision therapy was the best treatment for convergence insufficiency. Convergence insufficiency is a vision problem where the two eyes don't work together in unison the way they are supposed to when one is reading. The result can make reading very difficult.


It is estimated that least one out of every 20 school-age children is impacted by convergence insufficiency.  However, there are other visual abnormalities to be considered. It is estimated that over 60% of problem learners have undiagnosed vision problems contributing to their difficulties.


The good news is the majority of these vision problems can be treated with a program of optometric vision therapy. The study by the NEI found that in-office vision therapy was the best treatment for convergence insufficiency.


The five most common signs that a vision problem may be interfering with your child's ability to read and learn are:


1. Skips lines, rereads lines;

2. Poor reading comprehension;

3. Takes much longer doing homework than it should take;

4. Reverses letters like b's into d's when reading; and

5. Has a short attention span with reading and schoolwork.

Any one of these symptoms is a sign of a possible vision problem.

Here is this press release issued by the NEI on convergence insufficiency:

More Effective Treatment Identified for Common Childhood Vision Disorder

NEI Press Release

National Institutes of Health
National Eye Institute

October 13, 2008


Scientists have found a more effective treatment for a common childhood eye muscle coordination problem called convergence insufficiency (CI). For words on a page to appear in focus a child's eyes must turn inward, or converge. In CI, the eyes do not converge easily, and as a result, additional muscular effort must be used to make the eyes turn in.


While the majority of eye care professionals treat children diagnosed with CI using some form of home-based therapy, a new study concludes that office-based treatment by a trained therapist along with at-home reinforcement is more effective. The research, reported in the Oct.13 issue of Archives of Ophthalmology, was funded by the National Eye Institute (NEI), part of the National Institutes of Health.

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. Symptoms of CI include loss of place, loss of concentration, reading slowly, eyestrain, headaches, blurry vision, and double vision.

“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.”


The CITT, which included 221 children age 9 to 17, is the first to compare three forms of vision therapy and a placebo therapy option. The first therapy was the current treatment standard known as home-based pencil push-up therapy, an exercise in which patients visually followed a small letter on a pencil as they moved the pencil closer to the bridge of their nose. The goal was to keep the letter clear and single, and to stop if it appeared double. The second group used home-based pencil push-ups with additional computer vision therapy. The third attended weekly hour-long sessions of office-based vision therapy with a trained therapist and performed at-home reinforcement exercises. The last group was given placebo vision activities designed to simulate office-based therapy.


After 12 weeks of treatment, nearly 75 percent of children who were given the office-based vision therapy along with at-home reinforcement achieved normal vision or had significantly fewer symptoms of CI. Only 43 percent of patients who completed home-based therapy alone showed similar results, as did 33 percent of patients who used home-based pencil push-ups plus computer therapy and 35 percent of patients given a placebo office-based therapy.


“There are no visible signs of this condition; it can only be detected and diagnosed during an eye examination,” said principal investigator Mitchell Scheiman, O.D., 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. This is very encouraging news for parents, educators, and anyone who may know a child diagnosed with CI.”


A 12-month follow-up study is being conducted to examine the long-term effects of these CI treatments. Further information about the reported trial, NCT 00338611, can be found at


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Convergence insufficiency infographicContent



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