Regimens of Intermittent Occlusion Therapy for Amblyopia in Children

July 18, 2022 updated by: Salus University

Intense vs Standard Regimens of Intermittent Occlusion Therapy for Unilateral Moderate Amblyopia in Children

This study is designed to answer the question: What if the Intermittent Occlusion (IO-therapy) glasses were prescribed all day (12-hours) in which the total time of treatment only took 4 weeks instead of the current treatment time (4 hours) in which it takes 12 weeks?

Children aged 3- to 8-years with untreated moderate unilateral amblyopia will be enrolled and randomized into 2 groups: 1) Intense 12-hour IO-therapy Group for 4 weeks treatment; or 2) Standard 4-hour IO-therapy glasses Group for 12 weeks treatment.

Study Overview

Status

Terminated

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Actual)

32

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Pennsylvania
      • Elkins Park, Pennsylvania, United States
        • Salus University

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

5 months to 4 years (Child)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

The following criteria must be met for the patient to be enrolled in the study:

  1. Age 3 to < 8 years
  2. Unilateral amblyopia associated with strabismus (comitant or incomitant), anisometropia, or both

    Criteria for strabismus: At least one of the following criteria must be met:

    • Heterotropia at distance and/or near fixation on examination (with or without spectacles)
    • History of strabismus surgery
    • Documented history of strabismus which is no longer present (which in the judgment of the investigator could have caused amblyopia)

    Criteria for anisometropia: At least one of the following criteria must be met:

    • >0.50 D difference between eyes in spherical equivalent
    • >0.50 D difference between eyes in astigmatism in any meridian
  3. Amblyopic eye has no myopia (> -0.25 D spherical equivalent).
  4. Visual acuity, measured in each eye without cycloplegia within 7 days prior to enrollment using the ATS single-surround HOTV letter protocol as follows:

    • Visual acuity in the amblyopic eye between 20/40 and 20/80 inclusive
    • Visual acuity in the sound eye 20/32 or better
    • Inter-eye acuity difference ≥ 2 logMAR lines (i.e., amblyopic eye acuity at least 2 lines worse than sound eye acuity)
  5. No previous amblyopia treatment within 6 months.
  6. Spectacle correction (if applicable) for measurement of enrollment visual acuity must meet the following criteria and be based on a cycloplegic refraction within 6 months:

    • Requirements for spectacle correction:
    • For patients meeting criteria for only strabismus

      • Hypermetropia if corrected must not be undercorrected by more than +1.50 D spherical equivalent, and the reduction in plus sphere must be symmetric in the two eyes. Otherwise, spectacle correction is at investigator discretion.
    • For patients meeting criteria for anisometropia or combined-mechanism

      • Spherical equivalent must be within 0.50 D of fully correcting the anisometropia
      • Hypermetropia must not be undercorrected by more than +1.50 D spherical equivalent, and reduction in plus must be symmetric in the two eyes
      • Cylinder power in both eyes must be within 0.50 D of fully correcting the astigmatism
      • Cylinder axis in the spectacle lenses in both eyes must be within 6 degrees of the axis of the cycloplegic refraction

    Spectacles meeting above criteria must be worn either:

    • for 4 weeks immediately prior to enrollment, or
    • until visual acuity in amblyopic eye is stable (defined as two consecutive visual acuity measurements at least 4 weeks apart with no improvement of one line or more)
    • An acuity measurement done any of the following ways may be considered the first of two consecutive measurements:

      • in current glasses,
      • in trial frames with full correction of hypermetropia with cycloplegia, or
      • in new glasses.
  7. Wearing optimal spectacle correction for a minimum of 4 weeks at the time of enrollment.
  8. Ocular examination within 6 months prior to enrollment.
  9. Gestational age > 34 weeks and birth weight > 1500 grams
  10. Parent willing to accept randomization
  11. Parent willing to be contacted and has access to phone
  12. Parent does not anticipate relocation outside area within study period.

Exclusion Criteria:

  1. Amblyopic eye has myopia worse than -3.00 D spherical equivalent.
  2. Prior intraocular or refractive surgery
  3. Ocular pathologies that impact vision
  4. Cognitive impairment that prohibits accurate data collection

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

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

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Intense 12-hour IO-therapy Group
Participants wear 12-hour daily IO-therapy glasses for 4 weeks
Active Comparator: Standard 4-hour IO-therapy Group
Participants wear 4-hour daily IO-therapy glasses for 12 weeks

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Visual Acuity Improvement
Time Frame: 4 weeks for the Intense Group and 12 weeks for the Standard Group
visual acuity difference between the primary outcome measure and baseline in the amblyopic eye; visual acuity was measured with ATS- HOTV method
4 weeks for the Intense Group and 12 weeks for the Standard Group

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Stereoacuity Test
Time Frame: 4 weeks for the Intense Group and 12 weeks for the Standard Group

Stereoacuity in arcsec was converted to log scale. so log10(stereo) will be reported.

The higher value indicates a poorer binocular visual function.

4 weeks for the Intense Group and 12 weeks for the Standard Group
Objective Total Treatment Hours
Time Frame: 4 weeks for the Intense Group and 12 weeks for the Standard Group
Objective total treatment hours at the primary outcome visit measured with a microsensor
4 weeks for the Intense Group and 12 weeks for the Standard Group
Objective Adherence
Time Frame: 4 weeks for the Intense Group and 12 weeks for the Standard Group
objective adherence measured with a microsensor to the treatment regimen
4 weeks for the Intense Group and 12 weeks for the Standard Group

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

September 1, 2016

Primary Completion (Actual)

May 30, 2021

Study Completion (Actual)

May 30, 2021

Study Registration Dates

First Submitted

May 8, 2016

First Submitted That Met QC Criteria

May 9, 2016

First Posted (Estimate)

May 10, 2016

Study Record Updates

Last Update Posted (Actual)

July 25, 2022

Last Update Submitted That Met QC Criteria

July 18, 2022

Last Verified

May 1, 2022

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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