Full-Time Occlusion Therapy for Intermittent Exotropia in Children (IXT7)

Randomized Trial of Full-Time Occlusion Therapy for Intermittent Exotropia in Children

Determine whether full-time patching is more effective than observation for improving distance control of IXT after 3 months of treatment (on-treatment outcome).

Study Overview

• Status: Completed
• Conditions: Intermittent Exotropia
• Intervention / Treatment: Device: Eye Patch

Detailed Description

Understanding the effectiveness of intensive patching has important implications for managing children with IXT. If full-time patching is associated with improvement in distance control vs an observation group, then future studies can be conducted to evaluate different durations of full-time patching treatment, whether the effect is maintained off-treatment, and how full-time patching compares to other treatment strategies.

The purpose of this study is to determine whether full-time patching is more effective than observation for improving distance control of IXT after 3 months of treatment (on-treatment outcome).

• Study Type: Interventional
• Enrollment (Actual): 73
• Phase: Phase 3

Contacts and Locations

Study Locations

• United States
  • Alabama
    • Birmingham, Alabama, United States, 35294
      • UAB Pediatric Eye Care; Birmingham Health Care
  • Arkansas
    • Little Rock, Arkansas, United States, 72202
      • Arkansas Childrens
  • California
    • Berkeley, California, United States, 94720
      • Univ. of California- Berkeley
    • Fullerton, California, United States, 92831-1699
      • Southern California College of Optometry
    • Irvine, California, United States, 92697
      • Univ of California, Irvine- Gavin Herbert Eye Institute
    • Loma Linda, California, United States, 92354
      • Loma Linda University Health Care, Dept. of Ophthalmology
    • Palo Alto, California, United States, 94303
      • Stanford University
  • Illinois
    • Chicago, Illinois, United States, 60611
      • Ann & Robert H. Lurie Children's Hospital of Chicago
    • Lisle, Illinois, United States, 60532
      • Progressive Eye Care
  • Indiana
    • Bloomington, Indiana, United States, 47405
      • Indiana School of Optometry
  • Maryland
    • Baltimore, Maryland, United States, 21287-9028
      • Wilmer Eye Institute
  • Massachusetts
    • Boston, Massachusetts, United States, 02118
      • Boston Medical Center
    • Boston, Massachusetts, United States, 02453
      • Boston Children's Hospital Waltham
  • Michigan
    • Big Rapids, Michigan, United States, 49307
      • Michigan College of Optometry at Ferris State Univ
  • Minnesota
    • Rochester, Minnesota, United States, 55905
      • Mayo Clinic Department of Ophthalmology
  • Missouri
    • Kansas City, Missouri, United States, 64108
      • Children's Mercy Hospitals and Clinics
  • Nebraska
    • Omaha, Nebraska, United States, 68114
      • University of Nebraska Medical Center
  • New York
    • New York, New York, United States, 10036
      • State University of New York, College of Optometry
  • North Carolina
    • Durham, North Carolina, United States, 27710
      • Duke University Eye Center
  • Ohio
    • Columbus, Ohio, United States, 43210-1280
      • Ohio State University College of Optometry
    • Poland, Ohio, United States, 44514
      • Eye Care Associates, Inc.
  • Oregon
    • Portland, Oregon, United States, 97239
      • Casey Eye Institute
  • Pennsylvania
    • Philadelphia, Pennsylvania, United States, 19141
      • Salus University/Pennsylvania College of Optometry
  • Tennessee
    • Memphis, Tennessee, United States, 38104
      • Southern College of Optometry
  • Virginia
    • Norfolk, Virginia, United States, 23502
      • Virginia Pediatric Eye Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 3 years to 8 years (Child)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

Children under the care of a pediatric optometrist or pediatric ophthalmologist will be eligible for the study if they meet all the following criteria:

1. Age 3 to < 9 years

2. IXT meeting all of the following criteria:

   • Intermittent or constant XT at distance (mean distance control 2.0 or more) with at least 1 control measure of 3, 4 or 5 (i.e., indicating spontaneous tropia)
   • Either IXT, exophoria, or orthophoria at near (cannot have control score of 5 on all 3 near assessments)
   • Distance exodeviation between 15∆ and 50∆ by PACT
   • Near exodeviation between 0∆ and 50∆ by PACT
   • Near exodeviation does not exceed distance by more than 10∆ by PACT (convergence insufficiency-type IXT excluded)

3. Age-normal visual acuity in both eyes:

   • 3 years: 20/50 or better (>=63 letters)
   • 4 years: 20/40 or better (>=68 letters)
   • 5-6 years: 20/32 or better (>=73 letters)
   • 7-<9 years: 20/25 or better (>=78 letters)
4. Interocular difference in distance VA of 2 logMAR lines or less (10 letters or less on E-ETDRS for patients ≥7 years old). Testing by ATS HOTV for participants 3 to < 7 years old and by E-ETDRS for participants ≥7 years old.
5. Cycloplegic refraction within the last 7 months.
6. Refractive error between -6.00 D SE and +2.00 D SE (inclusive) based on a cycloplegic refraction within 7 months

7. Participants with refractive error meeting any of the following based on a cycloplegic refraction within 6 months must be wearing spectacles for at least 2 weeks:

   • Myopia > -0.50 D spherical equivalent (SE) in either eye
   • Anisometropia > 1.00 D SE
   • Astigmatism in either eye > 1.00 D

8. Any refractive correction worn at enrollment (required or not) must meet the following guidelines based on a cycloplegic refraction within 7 months:

   • Anisometropia SE must be within 0.50 D of the full anisometropic difference correction
   • Astigmatism must be corrected within 0.50 D
   • Axis must be within ±10 degrees if cylinder power is ≤1.00 D and within ±5 degrees if cylinder power is >1.00 D.
   • For hyperopia, the spherical component can be reduced at investigator discretion provided the reduction is symmetrical and does not meet the definition of deliberate overminus (see below).
   • For myopia, the intent is to fully correct, but the spherical component can be undercorrected at investigator discretion provided the reduction is symmetrical and results in no more than -0.50 D SE residual (i.e., uncorrected) myopia. Deliberate overminus is not allowed.

   • Deliberate overminus is defined for this protocol as any refractive correction prescribed to yield lenses that are overminused by more than -0.50D SE than cycloplegic refraction SE

     • Less than the full cycloplegic hyperopic correction (i.e., prescribing reduced plus) is not considered the same as overminusing for this protocol (because most patients without IXT but with hyperopic SE refractions up to +2.00 D SE would not typically be prescribed a refractive correction.)
   • For refractive errors with an emmetropic or myopic SE, the intent is to fully correct, but the spherical component can be undercorrected at investigator discretion provided the reduction is symmetrical and results in no more than -0.50 D SE residual (i.e., uncorrected) myopia. Prescribing a correction that yields more than 0.50 D more minus SE than the cycloplegic refraction SE is considered deliberate overminus and is not allowed.
   • Note that the refractive correction guidelines and the requirement to wear refractive correction for at least 2 weeks apply not only to participants who require refractive correction under the above criteria but also to any other participant who is wearing refractive correction.
9. Gestational age > 30 weeks
10. Birth weight > 1500 grams
11. Patient and/or parent understands protocol, is willing to enroll, and is willing to accept that other (i.e., nonrandomized) treatment for IXT will not be offered by the investigator for 3 months
12. Parent has phone and is willing to be contacted by Jaeb Center staff
13. Relocation outside of area of an active PEDIG site within 3 months not anticipated

Exclusion Criteria:

Individuals meeting any of the following criteria at baseline will be excluded from study participation:

1. Prior strabismus, intraocular, or refractive surgery (including BOTOX injection)
2. Prior nonsurgical treatment for IXT (e.g., patching, vergence therapy, vision therapy/orthoptics, base-in prism, or deliberate overminus (more than 1.00 D) spectacles of >1week duration within the past year
3. Previous amblyopia treatment other than refractive correction
4. Diplopia more than 2 times per day by parental assessment
5. Paretic or restrictive strabismus
6. Craniofacial malformations affecting the orbits
7. Ocular disorders which would reduce VA (except refractive error)
8. Severe developmental delay that would interfere with treatment or evaluation (in the opinion of the investigator). Participants with mild speech delay or reading and/or learning disabilities or ADHD are not excluded.
9. Neurological anomaly that could affect ocular motility (e.g., cerebral palsy, Down syndrome)
10. Immediate family member (child or sibling) of any investigative site personnel directly affiliated with this study.
11. Known allergy to adhesive patches.
12. Known allergy to silicone.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: Observation Group; Participants randomized to observation alone will not be allowed to receive any other treatment for IXT, except refractive correction, for 3 months.
Experimental: Full Time Patching; Participants randomized to the full-time patching group will patch full-time (all waking hours) for 3 months up until the day before the 3-month primary outcome visit. Daily alternate patching will be prescribed (right eye on even days, left eye on odd days). No other treatment for IXT will be used, except for refractive correction.	Device: Eye Patch; adhesive patch to cover eye

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants With a Change in Mean Distance Control Scores at 3 Months	To determine if participants with IXT undergoing full-time patching have more improvement in mean distance control between baseline and 3 months than participants being observed without treatment. The Office Control Score provides a rating of exodeviation control on a 0 to 5 scale, in subjects with intermittent exotropia. Scores 3 to 5 reflect the proportion of time a spontaneous manifest exotropia is present during 30 seconds of observation (<50% score 3; >50% score 4; 100% score 5). If no spontaneous manifest exotropia is observed, scores 0 to 2 reflect the longest time to regain fusion after three, 10-second dissociations (>5 seconds score 2; 1-5 seconds score 1; <1 second score 0).	3 months

Collaborators and Investigators

• Sponsor: Jaeb Center for Health Research
• Collaborators: National Eye Institute (NEI); Pediatric Eye Disease Investigator Group
• Investigators: Study Chair: Stephen P Christiansen, MD, Boston Children's Hospital; Study Chair: Erin C Jenewein, OD, Salus University

Publications and helpful links

General Publications

• Hatt SR, Leske DA, Holmes JM, Henderson RJ, Chandler DL, Morrison DG, Summers AI, Cotter SA. Testing depth of suppression in childhood intermittent exotropia. J AAPOS. 2022 Feb;26(1):36-38.e1. doi: 10.1016/j.jaapos.2021.08.303. Epub 2021 Nov 16.

Study record dates

Study Major Dates

• Study Start (Actual): November 1, 2022
• Primary Completion (Actual): May 1, 2025
• Study Completion (Actual): May 1, 2025

Study Registration Dates

• First Submitted: July 14, 2022
• First Submitted That Met QC Criteria: July 14, 2022
• First Posted (Actual): July 18, 2022

Study Record Updates

• Last Update Posted (Actual): December 2, 2025
• Last Update Submitted That Met QC Criteria: November 18, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: occlusion therapy; IXT; intermittent exotropia
• Additional Relevant MeSH Terms: Nervous System Diseases; Eye Diseases; Cranial Nerve Diseases; Ocular Motility Disorders; Strabismus; Exotropia
• Other Study ID Numbers: IXT7; 2U10EY011751 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: In accordance with the NIH data sharing policy, a de-identified database is placed in the public domain on the PEDIG public website after the completion of each protocol and publication of the primary manuscript.
• IPD Sharing Time Frame: Data will be made available after publication of each primary manuscript
• IPD Sharing Access Criteria: Users accessing the data must enter an email address.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No