A New Approach to Vision Therapy Based on Naturalistic 3-D Computer Gaming
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- Barron Associates, Inc.
- Enrollment
- 92
- Locations
- 1
- Primary Endpoint
- Visual Acuity
Study Overview
Brief Summary
The research team will execute two concurrent studies within a common framework. The first will compare iCare to standard of care occlusion therapy (patching) for amblyopia in patients ages 4 to 18 (inclusive). The second will compare iCare to a standard of care for home-based CI therapy (pencil pushups) for convergence insufficiency patients ages 8 to 18 (inclusive). In the context of this study, the term iCare refers to either the amblyopia or CI video game module as appropriate for the respective study group.
Detailed Description
Both the amblyopia and CI studies will follow the same basic approach. Each study will last 12 weeks, and participants will return for follow-up visits at Weeks 4, 8, and 12. Patients will receive full visual exams to establish baseline data upon enrollment, and again at Week 12 to record post-treatment data. During the interim visits (Weeks 4 and 8), patients' visual function will be assessed by a study optometrist, and any changes to the iCare configuration will be addressed as needed. As iCare is a home-based therapy, participants must have access to a personal computer and the Internet. For patients without access, the research team will provide loaner computers and/or pre-paid Verizon wireless mobile hotspots for Internet connectivity.
The proposed clinical studies will use the provider-as-investigator model that involves a minimum of 10 study sites and approximately 100 participants (see statistical power analysis below). With this approach, the research team will recruit optometry and vision therapy clinics and practices from around the country to support study execution under the training, guidance, and supervision of the iCare team. UND will serve as the coordinating center, enrolling, training, and overseeing the study sites and providing Institutional Review Board (IRB) governance.
The proposed effort is a Continuing Renewal application, with commercialization of the iCare product as its ultimate goal. By putting the iCare system directly in the hands of practicing optometrists and vision therapists, the research team can solicit feedback on features, commercialization models, and patient experiences. This will help ensure rapid transition of the test system to commercial adoption at the conclusion of the research effort.
A total of 10 centers from across the country have already provided letters of support indicating strong interest in participating (see letters of support herein). This demonstrates the breadth of outreach that has been conducted within the provider community as well as the high level of enthusiasm that exists for the iCare solution. Providers want access to this technology. Although all investigator-providers will be highly credentialed, qualified, and experienced vision therapy practitioners, not all will be experienced researchers. To ensure protection of human subjects, integrity of data, and reliability of results, the UND-Barron Associates team will: provide rigorously-complete step-by-step checklists for all procedures; conduct webinar-based training on detailed protocols; and promulgate specific instructions on data protection, patient safety, and research ethics. All investigator-providers will complete Collaborative Institutional Training Initiative (CITI) training and be registered with the UND IRB. During interactive online video training sessions, iCare team members will provide detailed instructions regarding study protocols to investigator-providers, including consent administration, inclusion/exclusion criteria, and assessments. Barron Associates, Inc. will provide thorough instructions on installation and use of the iCare system, the Provider Dashboard web app, and the parental-support web app. These will also be documented in printed manuals and online "how-to" videos. Each training webinar is expected to last 4 hours, with one-on-one "just-in-time" training available at any time. Follow-up teleconferences with the investigator-providers during study execution will reinforce patient protections and protocol adherence, as well as solicit recommendations on feature enhancements and integration of iCare into provider workflows.
The amblyopia and convergence insufficiency branches of the study will run concurrently at the participating study sites. Study details specific to each are described below.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Treatment
- Masking
- None
Eligibility Criteria
- Ages
- 4 Years to 18 Years (Child, Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •(Amblyopia Arms):
- •Age 4 to 18 (inclusive);
- •Diagnosis of amblyopia associated with anisometropia;
- •No amblyopia treatment (atropine, patching, vision therapy) in the past two weeks;
- •Spectacles (if required) worn for at least 16 weeks, or demonstrated stability of visual acuity (< 0.1 logMAR change by the same testing method measured on two exams at least four weeks apart);
- •Visual acuity in the amblyopic eye of 20/40 or worse;
- •Visual acuity in the fellow eye of 20/25 or better;
- •Interocular difference ≥ 0.3 logMAR (3 logMAR chart lines);
- •No myopia greater than -6.00D spherical equivalent in either eye;
- •Demonstrate in-office ability to play the iCare training game under binocular condition
Exclusion Criteria
- •(Amblyopia Arms):
- •Prism in the refractive correction at time of enrollment;
- •Previous intraocular or refractive surgery;
- •Any treatment for amblyopia in the past two weeks;
- •Down syndrome or cerebral palsy or other severe developmental delay that would interfere with treatment or evaluation;
- •Heterotropia or heterophoria with a total ocular deviation > 10∆ at near.
- •Inclusion Criteria (CI Arms):
- •Best-corrected visual acuity of ≥ 20/25 in each eye at distance and near;
- •Exophoria at near at least 4∆ greater than at distance;
- •Reduced positive fusional convergence at near (< 20∆ or fails Sheard's criterion that the PFV measures less than twice the magnitude of the near phoria);
- •Near point of convergence of ≥ 6 cm break;
- •CI Symptom Survey Score of ≥ 16;
- •No use of a plus add for near or base-in prism for at least two weeks preceding enrollment;
- •Patient must be wearing appropriate refractive correction for at least two weeks prior to enrollment, if necessary;
- •Demonstrate in-office ability to play the iCare training game under binocular conditions.
- •Exclusion Criteria (CI Arms):
- •≥ 0.2 logMAR (2 line) difference in best-corrected visual acuity between the two eyes;
- •Constant or intermittent exotropia at distance; constant exotropia at near;
- •Any esotropia at distance or near;
- •Distance exophoria ≥ 10∆;
- •History of strabismus surgery;
- •Anisometropia ≥ 2.00D in any meridian between the eyes;
- •Prior intraocular or refractive surgery;
- •Primary vertical heterophoria greater than 1∆;
- •Diseases known to affect accommodation, vergence, and ocular motility;
- •Current use of ocular or systemic medication known to affect accommodation or vergence;
- •Near point of accommodation > 20cm in the right eye;
- •Manifest or latent nystagmus clinically evident;
- •Down syndrome, cerebral palsy, or other severe developmental delay, or learning or attention disability that in the investigator's discretion will interfere with treatment or evaluation;
- •Acquired brain injury;
- •Previous vision therapy treatment for CI within the previous 6 months.
Arms & Interventions
Amblyopia standard of care group
A standard of care group will be prescribed patching for two or six hours per day, seven days per week. Standard of care group participants with best-corrected vision worse than 20/200 in their amblyopic eye will be prescribed six hours of patching daily, while participants whose best-corrected visual acuity is 20/200 or better will be prescribed two hours of patching daily.
Intervention: Amblyopia standard of Care (Behavioral)
Amblyopia iCare group
Participants assigned to an experimental group will play iCare vision therapy games for approximately 20 minutes per day, five days per week.
Intervention: iCare (Device)
Convergence insufficiency standard of care group
A standard of care group for convergence insufficiency will perform pencil pushups for 20 minutes per day, five days per week.
Intervention: CI standard of Care (Behavioral)
Convergence insufficiency iCare group
The iCare experimental group for convergence insufficiency will be prescribed vision therapy gameplay for approximately 20 minutes per day, five days per week.
Intervention: iCare (Device)
Outcomes
Primary Outcomes
Visual Acuity
Time Frame: Pre- to post-intervention change in best-corrected vision (delta-logMAR) at 12 weeks
Pre- to post-intervention change in best-corrected vision measured using a logMAR (Logarithm of the Minimum Angle of Resolution) chart, which consists of rows of letters of different sizes. The scale ranges from -0.3 (approximately 20/10 vision on the Snellen chart) to 1 (approximately 20/200 vision). Lower scores indicate better vision.
Positive Fusional Vergence (PFV) Base-Out Breakpoint (BOB)
Time Frame: Pre- to post-intervention change in BOB (delta-BOB) at 12 weeks
Cover Testing procedures were followed by evaluation of PFV at near using base-out prisms. A single column of 20/30 letters of the Gulden Fixation stick was advanced towards the subject from the distance of 40cm from the subject's eyes, while the subject continued fusing the letters (keeping them single) while viewing them through a corresponding prism. The magnitude of the prism was increased (for break point) and subsequently decreased (for recovery point) at a rate of about 2∆ /second. The procedure was repeated 3 times and the blinded examiner recorded blur, break and recovery points in prism diopters (∆). Larger numbers are better.
Secondary Outcomes
- Near Point of Convergence (NPC) at Break(Pre- to post-intervention change at 12 weeks)
- Convergence Insufficiency Symptom Survey (CISS)(Pre- to post-intervention change at 12 weeks)