Visual Perceptual Learning Based Digital Therapeutics for Stereopsis in Intermittent Exotropia

Study Overview
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Brief Summary
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This study evaluates the efficacy and safety of visual perceptual learning for improving stereopsis in intermittent exotropia. Half of participants will receive visual perceptual training using the Nu.T. The other half will not receive any training because there is no standard treatment for decreased stereopsis in intermittent exotropia.

Official Title
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Efficacy and Safety of the Nu.T for Improving Impaired Stereopsis Caused by Intermittent Exotropia : Multi Center, Randomized, Single-blind (Evaluator), Prospective Confirmatory Study

Conditions
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Intermittent Exotropia

Intervention / Treatment
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* Device: Nu.T
* Other: No-Treatment Control


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Intermittent Exotropia patients aged 6 to 15 Patients with decreased stereopsis above 50 arc seconds in Titmus Dot Test Able to use the Virtual Reality(VR) device Patient or legally authorized representative has signed the informed consent form Exclusion Criteria: Incomitant strabismus patient with impaired eye movement Patients with amblyopia (Maximal corrective vision of one eye is less than 0.8 or maximal corrective vision both eyes more than two lines of difference) History of ophthalmic surgery Patient who has undergone or is currently undergoing cover treatment within one month for the purpose of treating strabismus or amblyopia Scheduled for ophthalmic surgery during the clinical trial participation period (8 weeks in the treatment group as of the registration date, Maximum 16 weeks in the control group as of the registration date) Difficult to understand and perform the stereopsis test. Abnormal Retinal Correspondence Patient with neurological abnormalities other than strabismus History of premature birth Participating in other clinical trial Any other condition that, in the opinion of the investigator, precludes participation in the trial

Ages Eligible for Study
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Minimum Age: 6 Years
Maximum Age: 15 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Nu.T<br>Nu.T, 5 times a week for 8 weeks. | Device: Nu.T<br>* Participants receive visual perceptual training using the Nu.T software.<br>|
| Other: No-treatment Control<br>No-treatment was administered during control period. | Other: No-Treatment Control<br>* No-treatment was administered during control period.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in (log) arc second of stereopsis from Baseline to 8 weeks | Stereopsis will be evaluated by a Titmus Dot Test. | 8 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Proportion of subjects showing improved stereopsis at 8 weeks compared to baseline | Improved stereopsis means more than 2 steps increase in Titmus Dot Test. | 8 weeks | 
| Changes of Stereopsis based on Titmus Symbol Test from baseline to 8 weeks | Stereopsis will be evaluated by Titmus Symbol Test. | 8 weeks | 
| Changes of Stereopsis based on Distance Randot Stereotest from baseline to 8 weeks | Stereopsis will be evaluated by Distance Randot Stereotest. | 8 weeks | 
| Changes of strabismus angle from baseline to 8 weeks | Strabismus angle will be evaluated by distance and near-field. | 8 weeks | 
| Changes of convergence capability score from baseline to 8 weeks | Convergence capability will be evaluated in distance and near-field by LACTOSE System. The scores by LACTOSE System range from 0 to 4. | 8 weeks | 
| Changes of visuo-motor function from baseline to 8 weeks. | Visuo-motor function will be evaluated by the Bruininks-Oseretsky Test of Motor Proficiency Second Edition (BOT-2) test. | 8 weeks |