Botulinum Toxin to Improve Results in Epicanthoplasty

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.