Raghuram A, et al. - Authors evaluated the frequency of visual deficits (specifically vergence, accommodation, and ocular motor tracking) in children with developmental dyslexia (DD) vs a control group of typically developing readers. As per data, in school-aged children with DD, deficits in visual function were far more prevalent than in TD readers. Nonetheless, there was an uncertainty regarding the possible cause and clinical relevance of these deficits.

Methods

• Experts conducted a prospective, uncontrolled observational study from May 28 to October 17, 2016, in an outpatient ophthalmology ambulatory clinic among 29 children with DD and 33 typically developing (TD) children.
• Frequencies of deficits in vergence (amplitude, fusional ranges, and facility), accommodation (amplitude, facility, and accuracy), and ocular motor tracking (Developmental Eye Movement test and Visagraph eye tracker) were included in the primary outcomes.

Results

• As per data, among the children with DD (10 girls and 19 boys; mean [SD] age, 10.3 [1.2] years) and the TD group (21 girls and 12 boys; mean [SD] age, 9.4 [1.4] years), accommodation deficits were more frequent in the DD group than the TD group (16 [55%] vs 3 [9%]; difference=46%; 95% CI, 25%-67%; P < .001).
• Results demonstrated that for ocular motor tracking, scores were in the impaired range in 18 children in the DD group (62%) (in the Developmental Eye Movement test, Visagraph, or both) vs 5 children in the TD group (15%) (difference, 47%; 95% CI, 25%-69%;P < .001).
• Findings suggested the occurrence of vergence deficits in 10 children in the DD group (34%) and 5 children in the TD group (15%) (difference, 19%; 95% CI, -2.2% to 41%;P=.08).
• In all, deficits in 1 or more domain of visual function was seen in 23 children in the DD group (79%) and 11 children in the TD group (33%) (difference, 46%; 95% CI, 23%-69%;P < .001).