Abstract: PURPOSE: To evaluate the cognitive function of children with strabismus and investigate the influence of main clinical indexes of strabismus on cognitive function in children.
METHODS: Prospective cross-sectional study.
RESULTS: A total of 149 participants aged 4 to 10 years were enrolled, including 83 patients with exotropia (exotropia group), 30 patients with esotropia (esotropia group), and 36 normal individuals (normal group). Cognitive function was assessed using the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) and the Wechsler Preschool and Primary Scale of Intelligence-Fourth Edition (WPPSI-IV), including the Verbal Comprehension Index (VCI), Perceptual Reasoning Index (PRI), Working Memory Index (WMI), Processing Speed Index (PSI), and Full-Scale Intelligence Quotient (FSIQ). The FSIQ, VCI, PRI, and PSI scores of both exotropia and esotropia groups were significantly lower than those of the normal group (P < 0.001, P < 0.001, P < 0.001, P = 0.001), while the WMI score did not differ significantly between the two groups (P = 0.144). However, there was no significant difference between the exotropia and esotropia groups. Spearman correlation analysis showed that the FSIQ, VCI, and PRI scores were negatively correlated with the duration of symptoms (r = -0.233, P = 0.01; r = -0.241, P = 0.01; r = -0.219, P = 0.02), and the FSIQ, VCI, PRI, and PSI scores were negatively correlated with near stereoacuity (r = -0.280, P < 0.001; r = -0.226, P = 0.01; r = -0.317, P < 0.001; r = -0.195, P = 0.01; r = -0.195, P = 0.02), far stereoacuity, and fusion for both near and far distances. The WMI score was only negatively correlated with fusion for near distances (r = -0.182, P = 0.03). However, there was no significant correlation between the type and deviation of strabismus and cognitive function in strabismus children.
CONCLUSIONS: There are differences in cognitive function between children with strabismus and normal children. The cognitive functions of verbal comprehension, perceptual reasoning, and processing speed are impaired in children with strabismus, while working memory is not affected. The cognitive impairment in children with strabismus may be due to abnormal binocular visual function.

Key words: Strabismus, Children, Cognition