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
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

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 October 01, 2014