The effect of low hypermetropia correction and office-based orthoptic training on binocular vision parameters in children with convergence insufficiency

Abstract

Purpose

To determine the effect of low hypermetropia correction and orthoptic exercises on binocular visual function in children with symptomatic convergence insufficiency.

Methods

This was a prospective, randomized intervention with a 3-month follow-up. Consecutive pediatric patients with convergence insufficiency and hypermetropia who met inclusion criteria were randomly assigned to one of three treatment groups: spectacle correction and orthoptic training (group 1), spectacle correction alone (group 2) and orthoptic training alone (group 3). The correction of hypermetropia ranged from +0.50 D to +2.25 D. All patients underwent an orthoptic examination, and the severity of functional symptoms was assessed.

Results

A total of 55 patients (28 females, 27 males) were included. There were no treatment-related changes in visual acuity or angle of phoria. Statistically significant reductions in the near point of convergence occurred in group 1 (−5.5 ± 6.8 cm [P = 0.001]) and in group 2 (−5.1 ± 4.8 cm [P = 0.001]). Fusional convergence for distance improved in groups 1 (P = 0.003), 2 (P = 0.018) and 3 (P = 0.006) but for near only in group 2 (P = 0.004). The largest improvement in the mean accommodative facility occurred in group 1 (P = 0.001). A significant decrease in the severity of functional symptoms was noted in all groups (P < 0.001 in groups 1 and 2 and P = 0.006 in group 3).

Conclusions

In our study cohort, correction of low hypermetropia positively influenced binocular vision parameters in patients with convergence insufficiency, suggesting that low hypermetropia correction should be considered for patients who undergo orthoptic training for convergence insufficiency.