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Three-year observation of children 12 to 35 months old with untreated intermittent exotropia
Susan A Cotter1, Brian G Mohney2, Danielle L Chandler3
1Southern California College of Optometry at Marshall B Ketchum University, Fullerton, California, USA.
Insights
Watchful waiting may be suitable for untreated intermittent exotropia (IXT) in young children. Most children with IXT did not experience motor deterioration over three years.
Area of Science:
- Ophthalmology
- Pediatric Ophthalmology
- Strabismus Research
Background:
- Intermittent exotropia (IXT) is a common strabismus in children.
- The optimal management strategy for untreated IXT in very young children remains debated.
- Early intervention versus observation is a key consideration in pediatric eye care.
Purpose of the Study:
- To describe the clinical course of untreated intermittent exotropia (IXT) in children aged 12-35 months.
- To determine the rate of deterioration in IXT over a 3-year follow-up period.
- To evaluate the need for treatment initiation based on observed clinical progression.
Main Methods:
- A prospective study of 97 children (12-35 months) with untreated IXT.
- Participants were randomized to observation in a trial comparing occlusion versus observation.
- Follow-up occurred at 3-month intervals for 3 years, with defined criteria for deterioration.
Main Results:
- The cumulative probability of deterioration by 3 years was 28% (95% CI: 20%-39%).
- Of those deteriorating, 7 experienced motor deterioration, and 17 received treatment without meeting motor deterioration criteria.
- The cumulative probability of motor deterioration alone was 10% (95% CI: 5%-19%).
Conclusions:
- Watchful waiting appears to be a reasonable initial management approach for IXT in children aged 12-35 months.
- The rate of motor deterioration was modest over the 3-year study period.
- Further long-term randomized trials are needed to confirm the efficacy of immediate treatment versus observation.
Purpose:
To describe the clinical course of untreated intermittent exotropia (IXT) in children 12-35 months of age followed for 3 years.
Methods:
We enrolled 97 children 12-35 months of age with previously untreated IXT who had been randomly assigned to the observation arm of a randomised trial of short-term occlusion versus observation. Participants were observed unless deterioration criteria were met at a follow-up visit occurring at 3 months, 6 months, and 6-month intervals thereafter for 3 years. The primary outcome was deterioration of the IXT by 3 years, defined as (1) a constant exotropia ≥10 prism dioptres (∆) at distance and near (i.e., motor deterioration) or (2) treatment prescribed despite not having met motor deterioration. The primary analysis used the Kaplan-Meier method to determine the cumulative proportion of participants meeting deterioration by three years and 95% confidence interval (CI).
Results:
The cumulative probability of deterioration by 3 years was 28% (95% CI = 20%-39%). Of the 24 participants meeting the primary outcome of deterioration, seven met motor deterioration and 17 were prescribed treatment without meeting motor deterioration. The cumulative probability of motor deterioration by 3 years was 10% (95% CI = 5%-19%).
Conclusions:
Given the modest rate of motor deterioration over three years, watchful waiting may be a reasonable management approach in 12- to 35-month-old children with IXT. To confirm this recommendation would require a long-term randomised trial of immediate treatment versus observation followed by deferred treatment if needed.
