A randomized clinical trial of full-time alternate patching therapy for intermittent exotropia in children

Abstract

PURPOSE: To determine whether 3 months of prescribed full-time alternate patching is more effective than observation for intermittent exotropia (IXT) in children. METHODS: We enrolled 73 children aged 3 to <9 years with mean IXT distance control score (3 measures) ≥2 points (on a 0-5 [phoria constant tropia] scale) with at least one score ≥3, 4, or 5 (indicating spontaneous XT over 30-s observation) and a distance exodeviation of 15-50 prism diopters (Δ) by prism and alternate cover test (PACT), with the near deviation not exceeding the distance by > 10Δ. Children were randomly assigned to 3 months full-time patching (all waking hours, 7 days per week, alternating eyes) or observation. The primary outcome was change in mean distance IXT control at 3 months. RESULTS: Baseline mean (SD) distance control for children assigned to full-time patching (N = 36) and observation (N = 37) were 3.6 (0.9) and 3.6 (0.9) points; mean distance PACT was 27Δ (9) and 27Δ (8), respectively. The 3-month visit was completed by 33 (92%) of 36 and 35 (95%) of 37 children assigned to full-time patching and observation. Mean patching adherence was 4.1 h per day (95% CI: 2.8-5.5, N = 20) by participants who returned temperature sensor occlusion dose monitors and 7.4 h per day (95% CI: 5.8-8.9, N = 33) by review of at-home calendars and interviews with parent and child. At 3 months, children in the patching group had greater improvement in mean distance control than the observation group: 0.9 (1.3) versus 0.2 (1.1) points (difference = 0.62 points, 95% CI: 0.04-1.20, p = 0.04). There was also greater improvement in mean distance PACT: 6 (7) versus 2 (7) Δ, difference = 4Δ (95% CI: 1-8, p = 0.02). CONCLUSIONS: Three months of prescribed full-time alternate day patching improved distance control and magnitude of IXT in children 3-<9 years, despite mean adherence substantially less than the prescribed full-time regimen. Future studies should evaluate the durability of treatment effects and compare patching to other treatments. TRIAL REGISTRATION: Clinicaltrials.Gov, registered 14 July 2022, NCT05462821.