Accommodative function in school children with reading difficulties

Abstract

Prior findings suggest correlation between reading problems and accommodative function, but few studies have assessed accommodation in children with poor reading skills. Our aim was to characterize monocular accommodative amplitude, relative accommodation and binocular accommodative facility in a population of healthy, non-dyslexic primary school children with reading difficulties. We conducted a cross-sectional study on 87 poor readers and 32 control children (all between 8 and 13 years of age) in grades three to six recruited from 11 elementary schools in Madrid, Spain. In each subject with best spectacle correction, negative relative accommodation (NRA) and positive relative accommodation (PRA) were measured using a phoropter, monocular accommodative amplitude (MAA) was determined using the minus lenses method, and binocular accommodative facility (BAF) was measured using the Bernell Acuity Suppression Slide (VO/9) and a +/- 2.00 D accommodative demand for a period of 1 minute. Monocular accommodative amplitude was significantly lower (p < 0.001) in the group of poor readers (right eye 9.1 D +/- 2.3, left eye 9.0 D +/- 2.3) than in the control group (right eye 10.5 D +/- 1.7, left eye 10.5 D +/- 1.7). Binocular accommodative facility values were significantly lower (p < 0.05) in the poor readers (4.9 cpm +/- 3.1) than controls (6.3 cpm +/- 2.9). Negative and positive relative accommodation values were similar in both groups of children. This study provides data on the accommodative capacity of a population of children with reading difficulties. Our findings suggest a reduced monocular accommodative amplitude and binocular accommodative facility, such that this function should be assessed by an optometric clinician in children whose reading level is below average.