The Impact of Vergence Dysfunction on Myopia Control in Children Wearing Defocus Spectacle Lenses

Purpose: To investigate the impact of vergence dysfunction on myopia progression in children with Defocus incorporated multiple segments (DIMS) spectacle lenses. Patients and Methods: We retrospectively enrolled children prescribed DIMS spectacle lenses to slow myopic progression. Baseline vergence dysfunction was determined according to phoria at distance and near. Axial length (AL) measurement and cycloplegic subjective refraction were performed before fitting the lenses and at six-month and one-year follow-ups. The six-month and one-year AL and spherical equivalent (SE) change from baseline were calculated and compared in subgroups stratified with the type of vergence dysfunction. Results: Two hundred and ninety-two myopic children were included. Significant AL elongation and SE progression were observed at six months and one year (P < 0.05 for all comparisons). Multiple regression demonstrated that AL elongation at six months (P < 0.001) and one year (P < 0.001) was negatively correlated with age, and SE progression at six months was associated with age (P = 0.002). The AL elongation at six months in children with convergence excess was significantly greater than in normal myopic subjects (P = 0.011) and subjects with convergence insufficiency (P = 0.008), divergence excess (P = 0.007), divergence insufficiency (P = 0.024) and basic esophoria (P = 0.048) at six months. Conclusion: The present research demonstrated that vergence dysfunction influences myopia progression for myopic children with DIMS, and the children with convergence excess suffer from the greatest myopia progression among different types of vergence dysfunction.