Bilateral Refractive Amblyopia Treatment Study (ATS7)

This study has been completed.
Sponsor:
Collaborator:
Information provided by:
Jaeb Center for Health Research
ClinicalTrials.gov Identifier:
NCT00305955
First received: March 20, 2006
Last updated: March 23, 2010
Last verified: October 2009
  Purpose

The purpose of this study will be to:

  • Determine the amount of visual acuity improvement with treatment of presumed bilateral refractive amblyopia
  • Determine the time course of visual acuity improvement with treatment

Condition Intervention Phase
Bilateral Refractive Amblyopia
Device: Spectacles
Phase 3

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: Bilateral Refractive Amblyopia Treatment Study

Resource links provided by NLM:


Further study details as provided by Jaeb Center for Health Research:

Primary Outcome Measures:
  • Visual acuity of 20/25 or better in both eyes [ Time Frame: 52 weeks ] [ Designated as safety issue: No ]

Enrollment: 113
Study Start Date: August 2004
Study Completion Date: October 2006
Primary Completion Date: July 2006 (Final data collection date for primary outcome measure)
Intervention Details:
    Device: Spectacles
    optimal spectacle correction
    Other Name: spectacles
Detailed Description:

There is a paucity of literature on bilateral amblyopia that is due to a substantial amount of refractive error (hypermetropia or astigmatism), and it is limited principally to review articles and case reports. The incidence is not known, but in one study, 4 of 830 (0.5%) children examined at the time of entry into school had bilateral amblyopia. Schoenleber et al performed a retrospective review of office records and identified 184 children with > +4.00 diopters of hypermetropia in both eyes, 12 of whom (6.5%) had bilateral amblyopia of 20/50 or worse. Ten of the 12 children (83%) improved to 20/40 or better in both eyes over a mean follow-up time of 22 months. Werner and Scott reported 6 cases of bilateral hypermetropic amblyopia with a spherical equivalent of at least +5.00 D and an initial visual acuity of 20/40 or worse in both eyes. All 5 patients with follow up improved with glasses alone, and 2 of these 5 had a most recent visual acuity worse than 20/40 in one eye with follow-up less than one year. Cavazos et al identified 218 eyes with hyperopia > +5.00 D or astigmatism >+2.00 D. Of these, 82 (38%) of the dominant eyes had an initial corrected visual acuity less than 20/25. Most improved to > 20/25, but many patients were lost to follow-up. In ongoing studies, bilateral refractive amblyopia is being evaluated in Native Americans.

  1. Patients will be enrolled who have bilateral refractive error with hyperopia >+4.00 D and/or astigmatism >2.00 D and have visual acuity in each eye, measured using best correction derived from cycloplegic refraction, meeting the following criteria:

    • Using E-ETDRS testing for patients age 7 to <11 years: visual acuity 20 to 70 letters (20/40 to 20/400)
    • Using ATS HOTV testing for patients age 3 to <7 years visual acuity 20/50 to 20/400
  2. Enrolled patients will be prescribed spectacles, which will be paid for by the study.
  3. The patient will return for a Spectacle Baseline visit within 30 days, at which time the spectacles will be placed on the patient for the first time and binocular and monocular visual acuities will be measured.

    • Patients whose monocular acuity at the Spectacle Baseline Visit is 20/25 or better in both eyes will end the study
    • Patients whose monocular acuity at the Spectacle Baseline Visit is worse than 20/25 in at least one eye will begin a one-year period of study follow up
  4. Follow-up visits are required at 5±:1 week, 13±:2 weeks, 26±:4 weeks, and 52±:4 weeks.

    • If at any follow-up visit a patient's monocular acuity is 20/25 or better in both eyes, the patient should return for the 52-week visit only and may skip the interim follow-up visits.

Sample size: The study plans to enroll 100 patients. At least 50 patients will be enrolled who have an interocular difference of less than 3 lines by ATS HOTV or less than 15 letters by E-ETDRS at the Spectacle Baseline visit.

  Eligibility

Ages Eligible for Study:   3 Years to 10 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population

Community sample

Criteria

Inclusion Criteria:

  • Age 3 to <11 years
  • Able to perform single-surrounded single optotype visual acuity using the ATS HOTV protocol for children 3 to <7 years old and using the E-ETDRS protocol for children 7 to <11 years old
  • Monocular visual acuity in each eye, measured using trial frames or phoropter with best correction derived from cycloplegic refraction, meeting the following criteria:
  • Using E-ETDRS testing for patients age 7 to <11 years: visual acuity 20 to 70 letters (20/40 to 20/400)
  • Using ATS HOTV testing for patients age 3 to <7 years acuity 20/50 to 20/400
  • Refractive error that meets at least one of the following criteria in each eye:
  • Spherical equivalent >+4.00 D
  • Astigmatism >2.00 D
  • Investigator believes that the patient's reduced visual acuity is due to bilateral, refractive amblyopia
  • Investigator not planning to prescribe occlusion, patching or any other amblyopia treatment other than spectacles at this time
  • Cycloplegic refraction and ocular examination within 2 months prior to enrollment

Exclusion Criteria:

  • Myopia greater than -6.00 D of spherical power in plus cylinder form
  • Ocular cause for decreased acuity in either eye; nystagmus per se will not exclude a patient from the study
  • Refractive correction (spectacles or contact lenses) in past three months and no more than one month of refractive correction ever
  • Prior treatment for amblyopia (other than the refractive correction permitted in previous exclusion criteria)
  • Prior intraocular or refractive surgery
  • Use of contact lenses during the study
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT00305955

Locations
United States, North Carolina
Duke University Eye Center
Durham, North Carolina, United States, 27710
Sponsors and Collaborators
Jaeb Center for Health Research
Investigators
Principal Investigator: David K. Wallace, M.D. Duke University Eye Center
  More Information

Additional Information:
Publications:
Responsible Party: Roy W. Beck, M.D., Ph.D., Director, Jaeb Center for Health Research
ClinicalTrials.gov Identifier: NCT00305955     History of Changes
Other Study ID Numbers: NEI-101, 2U10EY011751
Study First Received: March 20, 2006
Last Updated: March 23, 2010
Health Authority: United States: Federal Government

Keywords provided by Jaeb Center for Health Research:
amblyopia
bilateral amblyopia
refractive error

Additional relevant MeSH terms:
Amblyopia
Brain Diseases
Central Nervous System Diseases
Nervous System Diseases
Vision Disorders
Sensation Disorders
Neurologic Manifestations
Eye Diseases
Signs and Symptoms

ClinicalTrials.gov processed this record on April 15, 2014