The effects on reading outcomes of vision therapy for convergence insufficiency

The effects on reading outcomes of vision therapy for convergence insufficiency

First Author: Carolyn A. Denton -- Oregon Research Institute
Additional authors/chairs: 
Mitchell Scheiman; Eric Borsting; Marjean Kulp; G. Lynn Mitchell; Susan Cotter; Christopher Chase; Lisa Jones-Jordan; Eugene Arnold; Richard Hertle; Michael Gallaway; Erica Schulman; Susanna Tamkins; Kristine Hopkins; Rachel Coulter; Ingryd Lorenzana
Keywords: Visual Impairment, Vision Therapy
Abstract / Summary: 

Convergence insufficiency (CI) is a condition in which the eyes have difficulty converging and tend to drift outward when looking at near objects. About 4% to 17% of school-aged children are estimated to have CI. CI has been associated with symptoms that could interfere with reading proficiency, including double vision, blurred vision, tired eyes, eye discomfort, headaches, and difficulty working up close. Specific to reading, persons with CI have reported loss of place while reading, frequent re-reading, loss of concentration, disfluent reading, and problems with reading comprehension. Office-based vision therapy has been found effective in treating symptoms and visual functioning in children with CI, but less has been known about the effects of this therapy on reading outcomes. This presentation will describe a program of research investigating the effects of CI vision therapy, including a recent randomized clinical trial that evaluated the effects of office-based CI therapy on reading for children in grades 3 to 8. In this study, children with symptomatic CI were randomized to receive office-based vergence/accommodative therapy (vision therapy) (n=206) or an office-based placebo therapy (n=104) that was specifically designed not to stimulate convergence and focusing. Participants were not selected on the basis of impaired reading, and they varied in their reading proficiency at pretest. Measures of vision and CI symptoms, as well as standardized measures of word reading, decoding, fluency, and comprehension, were administered at baseline and after 16 weeks of therapy. Standard scores on several reading measures improved for students in both the CI therapy and the placebo therapy groups after 16 weeks of therapy, but the groups did not differ significantly on any reading outcome.