Abstract
Purpose :
Do children with Intermittent Exotropia (IXT) have similar rates of myopic progression compared to children with normal eye alignment?
Methods :
A retrospective chart review was conducted for patients seen in Ophthalmology in 2017 for an IXT related visit. Included patients had more than one visit and were 3 to <18 years old at their baseline visit. Patients with strabismus surgery, ocular disease, or significant developmental delays were excluded. Patients were further screened for a myopic spherical equivalence (SE) of -0.5 to -6.0D in at least one eye. Data was abstracted for patient demographics, SE, distance and near deviation magnitudes from visits at baseline, first myopic (if not at baseline), closest to two years after first myopic, and most recent. The more myopic eye was used for analysis. Paired student t-tests determined differences in baseline and follow up data. Association between deviation and SE changes was assessed using Pearson correlation. Continuous data is presented as means and standard deviations.
Results :
Out of the 246 patient charts reviewed, 143 patients fit inclusion criteria and 58 had or developed myopia (30 females, 7.44 ± 3.37 years at baseline). Mean duration from baseline to most recent visit was 6.73 ± 3.64 years, and from first myopic to two-year follow up was 2.17 ± 0.87 years. The mean SE difference between baseline and most recent visit (Mean Difference (MD): -2.31 ± 1.60D, 95% Confidence Interval (CI): -1.89 – -2.73, p < 0.001), and between first myopic visit to two-year follow up (MD: -0.84 ± 0.74D, 95% CI: -0.64 – -1.03, p < 0.001) were both significantly different. 22 patients had a difference in SE of -1.00D or greater from first myopic visit to two year follow up with a mean change of -1.56 ± 0.55D. Distance and near deviation magnitudes were not significantly different between baseline and most recent visit. Change in myopic SE did not significantly correlate with change in distance and near deviation from baseline to most recent visit. Patients were treated with patching and/or eye exercises for management of IXT but none were prescribed over-minus spectacles.
Conclusions :
41% of eligible IXT patients had myopia which is comparable to the nation-wide prevalence of 42%. Our data showed a -0.42D increase in myopia per year which is very similar to the inferred per year progression from the MTS1 (-0.40D) and CHAMPS (-0.43D) studies with similar age-cohorts who did not have IXT.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.