Abstract
Purpose :
To evaluate the reading ability of children with intermittent exotropia (IXT) and explore potential correlations between reading abnormalities, vision and visual information processing capabilities.
Methods :
A prospective cross-sectional study. The Dyslexia Checklist for Chinese Children (DCCC) was employed to assess the reading abilities. Visual parameters were collected, including best corrected visual acuity spherical equivalent refractive, contrast sensitivity (CS), stereopsis, and fusion function. The Development Eye Movement test (DEM), the Test of Visual Perceptual Skills 4th Edition (TVPS), and the Beery Visual Motor Integration 6th Edition (VMI) were used to evaluate visual information processing capabilities.
Results :
This study included 55 children with IXT (9.56 ±1.81 years, 36 boys [65.5%] and 35 controls (9.46 ± 1.63 years, 22 boys [62.9%]) aged 7-13 years. The overall score of DCCC was significantly different between IXT (105.45 ±33.51) and controls (87 ±20.10) (t=3.26, p=0.002) showing that IXT performed poor reading ability than controls including oral language deficit (p=0.034), written expression deficit(p=0.040), bad reading habits (p= 0.005), attention deficit (p= 0.011), and vocabulary comprehension deficit (p=0.020). The CS of the binocular eye (BE), the dominant eye (DE), and the non-dominant eye (NDE) in IXT was lower than controls (p=0.02, p<0.0001, p=0.008), as well as binocular fusion and stereopsis. During BE, DE, and NDE viewing, the differences were mainly apparent for vertical test (VT) scores of DEM (p=0.035, p=0.021, p=0.045, respectively). The score for TVPS, and VMI in individuals with IXT was lower than controls (p=0.049, p=0.026, respectively). The DCCC scores significantly correlated with contrast sensitivity and visual information processing in children with IXT, including binocular CS (r=-0.251, p=0.017), VT of DEM during BE viewing (r=-0.240, p=0.023), and NDE viewing (r=-0.212, p=0.045), TVPS (r=-0.305, p=0.004), VMI (r=-0.440, p=p<0.0001).
Conclusions :
Reading ability in children with IXT is diminished compared to age-matched peers and is associated with binocular contrast sensitivity, saccades and vertical eye movements, visual perception, and visual motor integration abilities. Clinical interventions for children with IXT should simultaneously address the deficiencies in visual information processing.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.