Protective Effect of Biodegradable Collagen Implant (Ologen) in Scleral Thinning After Strabismus Surgery

Study Overview
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Brief Summary
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This study is to investigate protective effect of biodegradable collagen implant in scleral showing after lateral rectus recession in patients with exotropia.

Conditions
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Exotropia or Intermittent Exotropia

Intervention / Treatment
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* Device: lateral rectus recession with biodegradable collagen implant
* Procedure: Lateral rectus recession without biodegradable collagen implantation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with intermittent exotropia or constant exotropia Alternate prism cover test showed 20 prism diopters or more than 20 prism diopters exotropia Subjects who want to do strabismus surgery Exclusion Criteria: Subject who had previous strabismus surgery or other ocular surgery history Thyroid eye disease or other connective tissue disease Significant bleeding or scleral perforation during operation Subjects who need to do medial rectus resection, not lateral rectus recession Subjects who had a plan to do other intra or extraocular surgery within 3 months

Ages Eligible for Study
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Minimum Age: 10 Years
Maximum Age: 70 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: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Biodegradable collagen implant<br>Both eyes are needed to correct strabismus. One eye is randomly selected for the placement of biodegradable collagen implant. | Device: lateral rectus recession with biodegradable collagen implant<br>* Exotropia was treated with bilateral lateral rectus recession procedure. Lateral rectus recession was done. After lateral rectus recession, no degradable collagen implant was placed in the area, where lateral rectus was original inserted. One eye was randomly selected for the comparison.<br>|
| Active Comparator: Without biodegradable collagen implant<br>Strabismus surgery is done without placing of biodegradable collagen implant in the other eye. | Procedure: Lateral rectus recession without biodegradable collagen implantation<br>* Exotropia was treated with bilateral lateral rectus recession procedure. Lateral rectus recession was done in the other eye without placing biodegradable collagen implantation.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Scleral thinning assessed with slit photography | Scleral thinning at the area, where lateral rectus was originally inserted, was assessed with slit photography. Scleral thinning score was calculated from the Lab color model. | Postoperative 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ocular discharge assessed by questionnaire | Ocular discharge will be assessed by questionnaire. | Postoperative 1 week | 
| Tearing assessed by questionnaire | Tearing will be assessed by questionnaire. | Postoperative 1 week | 
| Foreign body sensation assessed by questionnaire | Foreign body sensation will be assessed by questionnaire. | Postoperative 1 week | 
| Collagen implant protrusion assessed by questionnaire | Collagen implant protrusion will be assessed by questionnaire. | Postoperative 1 week | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Biodegradable collagen implant, scleral thinning, strabismus surgery