Strabismus or prior successfully treated amblyopia does not impair binocular reading speed in adolescents

Childhood strabismus and amblyopia may affect reading ability. Previous studies have demonstrated slower reading speed among amblyopic children compared with controls, but the relationships between strabismus without amblyopia or prior treated amblyopia and reading speed have not been established. The purpose of this study was to investigate whether strabismus or history of successfully treated amblyopia independently affect binocular reading speed in adolescents and to characterize the clinical parameters associated with reading performance.

A total of 124 adolescents (10-17 years) were enrolled and divided into four groups: strabismic with prior successfully treated amblyopia, strabismic without prior amblyopia, nonstrabismic with prior successfully treated amblyopia, and control. Binocular reading speed was assessed using standardized passages from the IReST-Hebrew. Statistical analysis involved Wilcoxon tests to compare reading speeds between groups and Spearman correlations to explore associations with clinical variables.

No statistically significant differences in binocular reading speed were found between the four groups (all P > 0.05). Subgroup analysis revealed no significant differences based on strabismus type (esotropia vs exotropia). Within-group associations were observed: in the strabismic with prior amblyopia group, a significant negative correlation existed between reading speed and arcseconds of stereopsis (r = -0.51, P = 0.01), whereas in the nonstrabismic with prior amblyopia group, reading speed correlated negatively with near point of convergence (r = -0.47, P = 0.02).

In our study cohort, nonamblyopic adolescents with a history of strabismus, amblyopia, or both did not exhibit slower binocular reading speed than controls. These findings suggest that in adolescents without current amblyopia or after successful amblyopia treatment, reading performance is preserved.