An interventional study of Vision Therapy in Intermittent Exotropia, sponsored by Southern California College of Optometry at Marshall B. Ketchum University. Completed at 6 sites in United States. Open to participants aged 8 Years to 16 Years. Per ClinicalTrials.gov, last updated 2026-09-03.
Sponsored by Southern California College of Optometry at Marshall B. Ketchum University · Not applicable, Interventional, and Treatment
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.
Vision therapy (VT) is a commonly prescribed treatment for children with intermittent exotropia (IXT). The effectiveness of VT as a treatment modality for children with IXT is unknown because previous studies have largely limited observational or retrospective case series without comparison groups. The objective of this multi-centered pilot randomized trial of VT for IXT compared to observation is to 1) determine the short-term effectiveness of VT on distance intermittent exotropia and 2) determine the feasibility of recruitment and retention of children aged 8 to 16 years old with IXT to participate in a randomized trial of 20 weeks of in-office VT. The results of this trial will provide the needed information to plan and conduct a large-scale randomized trial to determine short-term and long-term effectiveness of VT for IXT in children, with the full-scale randomized trial helping to fill in the gaps in scientific knowledge concerning VT as a treatment for IXT.
Major Inclusion Criteria-
Intermittent exotropia meeting all of the following:
Major Exclusion Criteria-
Participants will receive 20 consecutive weeks of office-based vision therapy with home therapy.
Other: Vision Therapy
Participants will receive no treatment for IXT is received during the study unless one of the deterioration criteria is met.
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.
Also known as: Orthoptics
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).
Time frame: 21 weeks
No Spontaneous Tropia
The proportion of participants with no spontaneous tropia at outcome will be compared between treatment groups.No spontaneous tropia is defined as control score of 2 or less on all three assessments of control at distance and near and no exotropia lasting more than 5 seconds throughout the examination.
Time frame: 21 weeks
Change in Distance Control
The proportion of participants with \>= 1 point change in control and \>= 2 points change in control will be compared between treatment groups.
Time frame: 21 weeks
Change in Vergence and Accommodative Measures
The near point of convergence, positive and negative fusional vergence ranges at distance and near, vergence facility, accommodative amplitude, and accommodative facility at outcome will be compared between treatment groups adjusting for the corresponding baseline value. The analysis will be completed separately for each vergence and accommodative measures.
Time frame: 21 weeks
Suppression Status
Suppression status will be compared at outcome between treatment groups, adjusting for baseline suppression status. Suppression status when the participant's eyes are in tropic position will be assessed using the suppression scale ranging from 0 (negligible suppression) to 4 (dense suppression).
Time frame: 21 weeks
Objective Eye Movement Recordings
Frequency of intermittent exotropia by objective eye movement recordings will be compared between treatment groups.
Time frame: 21 weeks
Plan to share: No
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This study is completed, as verified in May 2026. You cannot join it, but the record below documents what was studied.
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Southern California College of Optometry at Marshall B. Ketchum University