Impact of intermittent exotropia and surgical realignment on myopia progression in myopic children.

PURPOSE: To determine whether untreated intermittent exotropia (IXT) accelerates pediatric myopia and whether strabismus surgery modifies this risk.

METHODS

This retrospective study enrolled 259 children aged 6-14 years with spherical equivalent refraction (SER) ≤ -0.75 D; 90 orthotropic controls, 86 untreated IXT, and 83 post-surgery IXT (PS-IXT) with successful alignment. Exclusion criteria included prior ocular surgery, trauma, or myopia-control interventions. After standardized cycloplegia, certified optometrists measured SER and axial length (AL) at baseline, 6 and 12 months.

RESULTS

Baseline SER, AL, age and gender distribution did not differ among the three cohorts (all P > 0.05). At the 12-month endpoint, the IXT group exhibited a significantly greater myopic shift (-0.91 ± 0.36 D vs -0.50(-0.75,-0.37) D; P < 0.001) and axial elongation (0.41 ± 0.17 mm vs 0.30(0.20,0.36) mm; P < 0.001) relative to orthotropic controls. Similarly, when compared with the surgically aligned (PS-IXT) group, the IXT cohort displayed excess myopic progression (-0.91 ± 0.36 D vs -0.38(-0.63,-0.13) D; P < 0.001) and axial elongation (0.41 ± 0.17 mm vs 0.25(0.13,0.37) mm; P < 0.001). In contrast, the PS-IXT and control groups were comparable for both refractive change (-0.50(-0.75,-0.37) D vs -0.38(-0.63,-0.13) D; P = 0.204) and axial elongation (0.30(0.20,0.36) mm vs 0.25(0.13,0.37) mm; P = 0.998).

CONCLUSION

Untreated IXT constitutes an independent, modifiable driver of accelerated myopia in children; timely surgical realignment normalizes the subsequent refractive and axial trajectory and should be incorporated into comprehensive myopia-prevention strategies.