Botulinum Toxin to Improve Results in Epicanthoplasty

Study Overview
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Brief Summary
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Medial epicanthal fold is a common skin fold in the inner part of the eye in more than 50% Asia population, giving the illusion of a shorter palpebral fissure length and a wider intercanthal distance. Currently, various epicanthoplasty techniques have been well described to correct epicanthus fold. However, hypertrophic scarring after epicanthoplasty remains a clinical challenge, which seems inevitable and may leading to unpleasing supratarsal crease, recurrence of medial epicanthus fold, even obvious scar formation. Botulinum toxin type A (BTX-A) is widely used for facial rejuvenation and many other medical indications. It is a potent neurotoxin that indirectly blocks neuromuscular transmission and leads to functional denervation of striated muscle for 2 to 6 months after injection. Recently, experimental study and clinical trails have revealed that BTX-A can inhibit the growth of fibroblasts derived from hypertrophic scars and influenced the expression of transforming growth factor-β1. Therefore, we hypothesized that BTX-A can improve hypertrophic scarring after epicanthoplasty through release orbicularis oculi muscle tension, inhibit fibroblast growth, and reduce collagen production. The main aim of this trail is to evaluate the efficiency of BTX-A injection on improving hypertrophic scaring after epicanthoplasty.

Official Title
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Botulinum Toxin to Improve Results in Epicanthoplasty

Conditions
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Scar, Intercanthal Distance Ratio

Intervention / Treatment
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* Drug: Botulinum toxin type A
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients with moderate to severe congenital epicanthus. patients accept Park Z epicanthoplasty. Written informed consent given Exclusion Criteria: epicanthus caused by trauma, surgical injury. patients with both epicanthus and blepharopotosis. patients with blepharophimosis-ptosis-epicanthus inversus syndrome, or only inversus epicanthus patients underwent Botulinum Toxin Type A periocular injection within 6 months patients ever have been allergic to Botulinum Toxin Type A or any components of Botulinum Toxin Type A

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 35 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Botulinum toxin<br>5U Botulinum toxin in 0.1 mL normal saline, administered in one of the intercanthus | Drug: Botulinum toxin type A<br>* 5U botulinum toxin in 0.1 mL normal saline, injected in two points at one side, 2.5U per point, local injection<br>|
| Placebo Comparator: Normal Saline<br>0.1 mL normal saline, administered in the other intercanthus | Drug: Placebo<br>* 0.1 mL normal saline, injected in two points at one side, 0.05 mL per point, local injection<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Vancouver Scar scale | Vancouver scar scale measures pigmentation, vascularity, pliability and scar height on the postoperative 6 month F/U | 6 month | 
| intercanthal distance ratio | the ratio of the intercanthal distance to the interpupillary distance | 6 month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Photographic measurement | The scar width of the patient's picture at 6 month after surgery will be measured using photoshop CS3 extended. One ruler will be placed on the patient's nose before taken the photo. Then the scar width could be measured. | 6 month | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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epicanthoplasty, Botulinum Toxins, scar, intercanthal distance, blepharoplasty