Atzmon D, Nemet P, et al.

A randomized prospective masked and matched comparative study of orthoptic treatment versus conventional reading tutoring treatment for reading disabilities in 62 children.

Binocular Vision & Eye Muscle Surgery Quartrly, 8(2):p. 91-106, 1993.

Abstract: Controversies remain whether orthoptics and/or “visual training” can remedy reading disabilities. Therefore, and to extend our prior studies, we under took a comparative and controlled study. One hundred and twenty children with reading disability were tested extensively, matched and randomly divided into three groups: orthoptic, conventional (reading tutoring), and no-treatment control. Unfortunately, participants in the control group were unable to adhere to no-treatment and were deleted. Each of the 40 children in the first two groups had 40 sessions, 20 minutes daily.

Orthoptic treatment was directed to markedly increasing fusional convergence amplitudes for both near and distance to 60 D. The two treatments were also carefully matched in time and effort. Sixty-two children in 31 matched pairs completed the course of treatment and testing. The results were equal and statistically significant (P< .05) marked improvement in reading performance in both treatment groups on essentially all tests.

Orthoptic treatment, to increase convergence amplitudes to 60 D, is as effective as conventional in-school reading tutoring treatment of reading disabilities. An advantage of orthoptic treatment was that subjective reading and asthenopic symptoms (excessive tearing, itching, burning, visual fatigue, and headache) virtually disappeared after orthoptics. We recommend orthoptic treatment as: 1) an effective alternate primary treatment; 2) adjunctive treatment for those who do not respond well to standard treatment; and 3) as primary treatment in any case with asthenopic symptoms of /or convergence inadequacy.

----
Letter regarding the study above:

Dr. Firmon E. Hardenbergh, Chief of Ophthalmology and Ophthalmologist to the Harvard University Health Services wrote a letter on March 29, 1991 regarding orthoptic treatment and convergence insufficiency. This letter appeared in the journal of Binocular Vision and Eye Muscle Surgery Quarterly in the Spring of 1993.

"I have reviewed the report by Daniela Atzmon and Professor P. Nemet on the subject of the results of a study on the effect of orthoptic exercises on the academic performance of learning/reading disabled children with convergence insufficiency. In my opinion, this prospective study was well planned and is essentially double blinded since the reading testing was not administered by either the tutors or the orthoptists.

The results support the proposition that application of orthoptics to all learning/reading disabled or deficient children who manifest convergence insufficiency should be the first line of therapy. If reading ability does not improve significantly within four to six months, other interventions should then be instituted."