Clinical Trial: Increasing Patching for Amblyopia in Children 3 to < 8 Years Old

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Increasing Patching for Amblyopia in Children 3 to < 8 Years Old

Brief Summary: This study is designed to evaluate the effectiveness of increasing prescribed patching treatment from 2 to 6 daily hours after visual acuity has stabilized with initial treatment and amblyopia is still present. Children ages 3 to <8 years with visual acuity of 20/50 to 20/400 in the amblyopic eye will be enrolled in a run-in phase with 2 hours daily patching until no improvement, followed by randomization of eligible patients to patching 2 hours daily versus an average of 6 hours daily (42 hours per week). The primary objective is to determine if increasing patching dosage will improve visual acuity in patients with amblyopia still present after visual acuity has stabilized with initial treatment.

Detailed Summary: Amblyopia is the most common cause of monocular visual impairment in both children and young and middle-aged adults. Both patching and atropine are accepted treatment modalities for the management of moderate amblyopia in children.1 Many practitioners prescribe 2 hours daily patching as initial therapy for amblyopia. However, many children fail to achieve normal visual acuity in the amblyopic eye with this regimen. In a randomized trial conducted by PEDIG comparing patching regimens, 71 of 92 patients with moderate amblyopia (77%) had amblyopic eye visual acuity of 20/32 or worse after 4 months of patching 2 hours daily.2 In another PEDIG randomized trial comparing patching to spectacles alone after a period of refractive adaptation, patients were treated with 2 hours daily patching and followed every 5 weeks until there was no improvement in amblyopic eye acuity. Fifty-five of 70 patients with moderate amblyopia (79%) and 14 of 14 patients with severe amblyopia (100%) had best-measured amblyopic eye visual acuity of 20/32 or worse after a median treatment period of 10 weeks.3 When improvement with initial therapy stops and amblyopia is still present, treatment options include increasing the dosage of current treatment, switching to another treatment, maintaining the same treatment and dosage for additional months, or combining treatments. Many clinicians will choose to increase the dosage of the current treatment, in part because families have become comfortable with that particular mode of treatment. However, it is unknown whether increasing occlusion dosage will improve amblyopic eye visual acuity in these patients. We are unaware of any reports of response to intensified treatment of amblyopia.
Sponsor: Jaeb Center for Health Research

Current Primary Outcome:

  • Distribution of 10-week Amblyopic Eye Visual Acuity [ Time Frame: 10 weeks after randomization ]

    The masked 10-week amblyopic eye visual acuity scores were tabulated for both treatment groups, and included data from 10-week visual acuity exams completed between 8 to 15 weeks (inclusive) with no imputation for missing data.

    The primary outcome analysis followed the "intent-to-treat" principle. Therefore, data from randomized participants were included in the analysis regardless of whether the assigned treatment was actually received or whether they deviated from treatment against protocol. In addition, randomized participants who were found to be ineligible upon subsequent review of enrollment data were included in the primary outcome analysis.

  • Mean 10-week Amblyopic Eye Visual Acuity [ Time Frame: 10 weeks after randomization ]

    The primary outcome analysis was a treatment group comparison of the masked 10-week amblyopic eye visual acuity using an analysis of covariance (ANCOVA) model, adjusting for visual acuity at randomization. The analysis included data from 10-week visual acuity exams completed between 8 to 15 weeks (inclusive) with no imputation for missing data.

    The primary outcome analysis followed the "intent-to-treat" principle. Therefore, data from randomized participants were included in the analysis regardless of whether the assigned treatment was actually received or whether they deviated from treatment against protocol. In addition, randomized participants who were found to be ineligible upon subsequent

    Original Primary Outcome: Amblyopic eye visual acuity [ Time Frame: 10 weeks after randomization ]

    Current Secondary Outcome:

    • Compliance With Prescribed Patching by Treatment Group at 10 Weeks [ Time Frame: 10 weeks after randomization ]
      The distribution of compliance with prescribed treatment was tabulated for the 10-week outcome and as averaged scores across all study follow-up visits. Compliance was evaluated as excellent (>75%), good (51%-75%), fair (26%-50%), or poor (<26%) based on discussions with the parent and by reviewing study calendars maintained by the parent, who recorded the number of hours the child patched each day.
    • Average Compliance With Prescribed Patching by Treatment Group [ Time Frame: 10 weeks after randomization or later ]
      The distribution of compliance with prescribed treatment was tabulated for the 10-week outcome and as averaged scores across all study follow-up visits. Compliance was evaluated as excellent (>75%), good (51%-75%), fair (26%-50%), or poor (<26%) based on discussions with the parent and by reviewing study calendars maintained by the parent, who recorded the number of hours the child patched each day.
    • Treatment Group Comparison of the Proportion of Participants Who Have Improved by 2 or More logMAR Visual Acuity Lines at 10 Weeks Since Randomization [ Time Frame: 10 weeks after randomization ]

      The proportion of participants who improved at least 2 logMAR lines since randomization was computed at the 10-week outcome.

      The secondary outcome analysis was a treatment group comparison of the proportion of participants whose 10-week masked amblyopic eye visual acuity improved at least 2 logMAR lines since randomization using logistic regression, adjusting for visual acuity at randomization. The analysis included data from 10-week visual acuity exams completed between 8 to 15 weeks (inclusive) according to the principles specified in the primary outcome analysis.

    • Treatment Group Comparison of 10-week Interocular Difference [ Time Frame: 10 weeks after randomization ]
      The secondary outcome analysis was a treatment group comparison of the 10-week interocular difference (IOD), computed as the difference between the masked amblyopic and fellow eye visual acuities, using an analysis of covariance (ANCOVA) model, adjusting for IOD at randomization. The analysis included data from 10-week visual acuity exams completed between 8 to 15 weeks (inclusive) according to the principles specified in the primary outcome analysis.
    • Distribution of Baseline Characteristics at the 10-week Outcome [ Time Frame: 10 weeks after randomization ]
      The number of participants was tabulated by treatment group within categorical levels of prespecified baseline subgroup factors for participants with 10-week visual acuity exams completed between 8 to 15 weeks (inclusive)according to principles specified in the primary outcome analysis.
    • Mean Amblyopic Eye Visual at Randomization According to Baseline Characteristics for 10-week Outcome [ Time Frame: 10 weeks after randomization ]
      Mean amblyopic eye visual acuity at randomization was computed by treatment group within categorical levels of prespecified baseline subgroup factors. The analysis included data from participants with 10-week exams completed between 8 to 15 weeks (inclusive) according to the principles specified in the primary outcome analysis.
    • Treatment Comparison of Mean Amblyopic Eye Visual Acuity Change at 10-weeks According to Baseline Characteristics [ Time Frame: 10 weeks after randomization ]
      A treatment comparison of mean amblyopic eye visual acuity change since randomization was performed at the 10-week outcome according to categorical levels of prespecified baseline subgroup factors. The analysis included data from participants with 10-week exams completed between 8 to 15 weeks (inclusive) according to the principles specified in the primary outcome analysis.
    • Distribution of Amblyopic Eye Visual Acuity at Visit of Best Post-randomization Visual Acuity [ Time Frame: 10 weeks after randomization or later ]
      Participants in both groups who have improved by one or more lines from randomization to the 10-week outcome exam will continue in the study and visits will occur every 10 weeks until no improvement of one or more lines from the previous visit. The distribution of best post-randomization (10 weeks or later) visual acuity scores in the amblyopic eye was tabulated for both treatment groups using the initial visual acuity score (if a retest was obtained.)
    • Mean Amblyopic Eye Visual Acuity at Visit of Best Post-randomization Visual Acuity [ Time Frame: 10 weeks after randomization or later ]
      Participants in both groups who have improved by one or more lines from randomization to the 10-week outcome exam will continue in the study and visits will occur every 10 weeks until no improvement of one or more lines from the previous visit. A treatment comparison of mean amblyopic eye visual acuity at the visit of best post-randomization visual acuity (10 weeks or later) was performed using an

      Original Secondary Outcome:

      • Sound eye visual acuity [ Time Frame: 10 weeks after randomization ]
      • Differences between treatment groups in stereoacuity [ Time Frame: 10 weeks after randomization ]
      • Ocular alignment [ Time Frame: 10 weeks after randomization ]
      • Treatment group comparison of the proportion of patients who have improved by 2 or more logMAR visual acuity lines [ Time Frame: 10 weeks after randomization ]
      • Patients in both groups who have improved by 1 or more lines from baseline to the 10-week outcome exam will have a treatment group comparison of the proportion of patients with at least 2 logMAR lines of visual acuity improvement [ Time Frame: Last study visit ]
      • Patients in both groups who have improved by 1 or more lines from baseline to the 10-week outcome exam will have a treatment group comparison of logMAR visual acuity scores in the amblyopic eye. [ Time Frame: Last study visit ]


      Information By: Jaeb Center for Health Research

      Dates:
      Date Received: July 21, 2009
      Date Started: August 2009
      Date Completion:
      Last Updated: July 12, 2016
      Last Verified: July 2016