Binocular Treatment of Amblyopia Before and After Strabismus Surgery
Condition: Amblyopia; Strabismus
MeSH terms: Amblyopia; Strabismus
Study type: Interventional

Summary: 
      The primary objective of this study is to assess the effectiveness of an investigational
      binocular treatment in improving vision in strabismic amblyopes (i.e., patients with lazy
      eye, or poor vision in one eye due to a present or former eye misalignment). Patients will be
      randomized to receive the study treatment either before or after strabismus surgery (i.e.,
      corrective eye alignment surgery) or sham treatment before surgery. The study hypothesis is
      that there will be no significant change in vision in neither the pre nor post-surgery groups
      and no significant change in vision in neither the sham nor actual treatment groups.
    

Detailed description: 
      This is a placebo-controlled, partially-randomized clinical trial. The patients will be
      assigned to one of two groups, Treatment Group A or Treatment B group. To help minimize bias,
      a blinded staff member will perform the visual acuity assessments throughout the study. The
      PI and Sub-I's will remain blinded to the treatment groups so that they may perform the
      visual exams throughout the study, if necessary.

      Patients who have had strabismus surgery prior to being recruited will be allowed to
      participate in the study and, if eligible, will be automatically assigned to Treatment Group
      A.

      Patients who are scheduled to have strabismus surgery at least six weeks from their screening
      clinic visit will be allowed to participate, once eligibility is determined. These patients
      will be included in Treatment Group B and randomized to either actual treatment or sham
      treatment. Each eligible participant will be included in the study and blinded as to which
      treatment group s/he has been assigned.

      The duration of each subject's participation in the study will be about 7.5 months. All
      subjects will have a baseline visit to assess eligibility. Subjects in Treatment Group A will
      undergo strabismus surgery, if it was not previously performed, followed by 6 weeks of
      binocular treatment and a 3-6 month follow-up period. NOTE: There will be 4-6 weeks between
      surgery and the start of treatment to allow for full post-surgery recovery before starting
      treatment. Subjects in Treatment Group B will undergo 6 weeks of treatment/sham followed by
      strabismus surgery and a 3-6 month follow-up period.

      If a treatment effect on vision is found, participants enrolled in the sham treatment arm
      will be offered the binocular treatment at the conclusion of the study and following surgery.
      Sham participants will be allowed to receive the study treatment so long as they have
      completed the study and there is no presence of any new medical condition following surgery
      that would be considered reasons for exclusion by the treating physician.
    

Intervention name(s): Binocular Treatment; Sham Binocular Treatment
Intervention type(s): Procedure; Procedure
Intervention description(s): The binocular treatment involves the completion of visual tasks via virtual reality goggles. The stimulus is presented to each eye separately, allowing for varying levels of contrast to be presented to each eye. (The visual task is therefore made more or less difficult with the variation of contrast presented to either eye.) Subjects will complete the computer-based visual tasks for approximately 36 hours total over the course of six weeks, or six hours per week for six weeks.; The sham treatment involves the same computer-based visual tasks and timeframe as the binocular treatment training but there will be no variation in contrast presentation to either eye.
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Treatment
Keywords: lazy eye; cross eye; cross eyed