Trial of Vision Therapy for Intermittent Exotropia
VT-IXT
A Pilot Randomized Trial Evaluating Short-Term Effectiveness of Vision Therapy in Children With Intermittent Exotropia
1 other identifier
interventional
58
1 country
6
Brief Summary
The main objective of this randomized trial comparing vision therapy to observation is to determine the short-term effectiveness of vision therapy on distance intermittent exotropia control. The results will help determine whether to proceed to a full-scale, long-term randomized trial.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P25-P50 for not_applicable
Started Oct 2021
Longer than P75 for not_applicable
6 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
Click on a node to explore related trials.
Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
July 17, 2020
CompletedFirst Posted
Study publicly available on registry
July 27, 2020
CompletedStudy Start
First participant enrolled
October 1, 2021
CompletedPrimary Completion
Last participant's last visit for primary outcome
December 1, 2025
CompletedStudy Completion
Last participant's last visit for all outcomes
December 1, 2025
CompletedMarch 5, 2025
March 1, 2025
4.2 years
July 17, 2020
March 4, 2025
Conditions
Keywords
Outcome Measures
Primary Outcomes (1)
Mean Distance Control Score
The primary analysis will be an intent-to-treat comparison of mean distance control score, determine by the intermittent exotropia office control scale, at outcome using an analysis of covariance model, which will adjust for baseline distance control. The intermittent exotropia office control scale grades the control on a scale of 0 (best control; phoria) to 5 (worst control; constant exotropia).
21 weeks
Secondary Outcomes (2)
No Spontaneous Tropia
21 weeks
Change in Distance Control
21 weeks
Other Outcomes (3)
Change in Vergence and Accommodative Measures
21 weeks
Suppression Status
21 weeks
Objective Eye Movement Recordings
21 weeks
Study Arms (2)
Vision Therapy
EXPERIMENTALParticipants will receive 20 consecutive weeks of office-based vision therapy with home therapy.
Observation
NO INTERVENTIONParticipants will receive no treatment for IXT is received during the study unless one of the deterioration criteria is met.
Interventions
20 consecutive weeks of office-based vision therapy with home therapy that aim to improve the participant's vergence skills, accommodative skills, and sensory fusion.
Eligibility Criteria
You may qualify if:
- Age 8 - 16 years
- Intermittent exotropia meeting all of the following:
- Distance exodeviation of 15∆ to 35∆ by prism alternating cover test (PACT)
- IXT, exophoria, or orthophoria at near
- Near exodeviation that does not exceed the distance exodeviation by more than 10∆
- Mean distance control score of 2 points or more with at least one measure being 3 points or higher
- Mean near control score less than 5 points
- Random dot stereopsis of 200" or better on Preschool Randot Stereotest
- Willingness to accept randomization and no plan to relocate in the next 6 months
You may not qualify if:
- Treatment for IXT or amblyopia (other than refractive correction) within 3 months prior to enrollment
- Office-based vision therapy for IXT within 6 months prior to enrollment
- Prior office-based vision therapy for IXT of ≥10 sessions
- Prior strabismus, intraocular, or refractive surgery (including BOTOX injection)
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Southern California College of Optometry at Marshall B. Ketchum Universitylead
- Stanford Universitycollaborator
- Ohio State Universitycollaborator
- Salus Universitycollaborator
- University of Alabama at Birminghamcollaborator
- Southern College of Optometrycollaborator
- Case Western Reserve Universitycollaborator
- American Academy of Optometrycollaborator
Study Sites (6)
University of Alabama in Birmingham
Birmingham, Alabama, 35294, United States
Southern California College of Optometry at Marshall B. Ketchum University
Fullerton, California, 92831, United States
Stanford University
Stanford, California, 94305, United States
Ohio State University
Columbus, Ohio, 43210, United States
Salus University
Philadelphia, Pennsylvania, 19141, United States
Southern College of Optometry
Memphis, Tennessee, 38104, United States
MeSH Terms
Interventions
Intervention Hierarchy (Ancestors)
Study Officials
- STUDY CHAIR
Angela Chen, OD, MS
Southern California College of Optometry at Marshall B. Ketchum University
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- not applicable
- Allocation
- RANDOMIZED
- Masking
- SINGLE
- Who Masked
- OUTCOMES ASSESSOR
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- OTHER
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
July 17, 2020
First Posted
July 27, 2020
Study Start
October 1, 2021
Primary Completion
December 1, 2025
Study Completion
December 1, 2025
Last Updated
March 5, 2025
Record last verified: 2025-03
Data Sharing
- IPD Sharing
- Will not share