The impact of intermittent exotropia and surgery for intermittent exotropia on myopic progression among early school-aged children with myopia

Aim To investigate the relationship between myopic progression and intermittent exotropia, and the impact of surgery for exotropia on myopic progression in early school-aged children (from 7 years to 12 years of age). Methods Medical records of early school-aged patients with myopia were reviewed. Patients were divided into three groups; (A) Patients with intermittent exotropia and myopia at presentation and who underwent bilateral lateral rectus muscle recession for exotropia when 7-12 years old; (B) Patients with intermittent exotropia and myopia at presentation and who were merely observed for exotropia; and (C) Patients with myopia and straight ocular alignment. Main outcome measurements were the simple rate of myopic progression per year, the preoperative and postoperative rates of refractive growth with regards to the logarithmic age model in Group A, and the rate of high myopia development at the end of the early school period. Results The rates of myopic progression were -0.43 +/- 0.14 dioptre (D) per year in Group A, -0.49 +/- 0.17 D/year in Group B and -0.42 +/- 0.24 D/year in Group C. There was no significant difference in the rate of myopic progression among three groups. There was no significant intergroup difference in the preoperative and postoperative rates of refractive growth in Group A. There were no significant intergroup differences in the rates of high myopia development among three groups. Conclusions Whether patients with intermittent exotropia underwent surgical correction for intermittent exotropia did not influence the rate of myopic progression. There was no significant difference in the rate of myopic progression between patients with accompanying intermittent exotropia and myopia and those with myopia alone.