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A randomized trial comparing part-time patching with observation for children 3 to 10 years of age with intermittent
, Susan A Cotter1, Brian G Mohney2
1Southern California College of Optometry, Marshall B. Ketchum University, Fullerton, California.
Insights
Part-time patching for intermittent exotropia (IXT) in children showed a slightly lower rate of deterioration compared to observation. Both approaches are considered reasonable for managing IXT in young children.
Area of Science:
- Ophthalmology
- Pediatric Ophthalmology
- Strabismus Management
Background:
- Intermittent exotropia (IXT) is a common childhood strabismus.
- Effective management strategies are crucial for preventing visual deterioration.
Purpose of the Study:
- To evaluate the efficacy of prescribed part-time patching in treating intermittent exotropia (IXT) in children.
- To compare the outcomes of part-time patching versus observation for IXT.
Main Methods:
- A multicenter, randomized clinical trial involving 358 children aged 3 to <11 years with untreated IXT.
- Participants were randomized to either observation or part-time patching (3 hours daily) for 5 months.
- Primary outcome was defined as deterioration based on exotropia measurements or stereoacuity decrease at 3 or 6 months.
Main Results:
- Deterioration occurred in 6.1% of the observation group versus 0.6% in the part-time patching group at 6 months.
- This represents a statistically significant difference in favor of part-time patching (P = 0.004).
- Overall, deterioration was uncommon in both groups over the 6-month study period.
Conclusions:
- Part-time patching demonstrated a slightly lower rate of deterioration for childhood IXT compared to observation.
- Both observation and part-time patching are considered reasonable management options for children aged 3 to 10 years with IXT.
- Further research may explore long-term outcomes and optimal patching durations.
Objective:
To determine the effectiveness of prescribed part-time patching for treatment of intermittent exotropia (IXT) in children.
Design:
Multicenter, randomized clinical trial.
Participants:
Three hundred fifty-eight children 3 to <11 years of age with previously untreated (except for refractive correction) IXT and near stereoacuity of 400 seconds of arc or better were enrolled. Intermittent exotropia met the following criteria: (1) IXT at distance OR constant exotropia at distance and either IXT or exophoria at near; (2) exodeviation (tropia or phoria) of at least 15 prism diopters (PD) at distance or near by prism and alternate cover test (PACT); and (3) exodeviation of at least 10 PD at distance by PACT.
Methods:
Participants were assigned randomly either to observation (no treatment for 6 months) or to patching for 3 hours daily for 5 months, with a 1-month washout period of no patching before the 6-month primary outcome examination.
Main Outcome Measures:
The primary outcome was deterioration at either the 3-month or the 6-month follow-up visit, defined as: (1) constant exotropia measuring at least 10 PD at distance and near by simultaneous prism and cover test, and/or (2) near stereoacuity decreased by at least 2 octaves from baseline, both assessed by a masked examiner and confirmed by a retest. Participants who were prescribed any nonrandomized treatment without first meeting either deterioration criteria also were counted as having deteriorated.
Results:
Of the 324 participants (91%) completing the 6-month primary outcome examination, deterioration occurred in 10 of the 165 participants (6.1%) in the observation group (3 of these 10 started treatment without meeting deterioration criteria) and in 1 of the 159 participants (0.6%) in the part-time patching group (difference, 5.4%; lower limit of 1-sided exact 95% confidence interval, 2.0%; P = 0.004, 1-sided hypothesis test).
Conclusions:
Deterioration of previously untreated childhood IXT over a 6-month period is uncommon with or without patching treatment. Although there is a slightly lower deterioration rate with patching, both management approaches are reasonable for treating children 3 to 10 years of age with IXT.
