Understanding botulinum toxin - Surgical anatomy of the frown, forehead, and periocular region

BACKGROUND. Cosmetic denervation of hyperfunctional facial lines using botulinum toxin (Botox, Allergan,. Inc., Irvine, CA) has gained growing popularity over recent years. Understanding the clinical use and effects of botulinum toxin requires a thorough understanding of the muscular anatomy of the treatment areas. OBJECTIVE. The purpose of this article is to review the anatomy of the frown, forehead, and periocular regions. Function of individual muscles is discussed to understand proper injection technique. CONCLUSIONS. The anatomy of the frown, forehead, and periocular regions is complex. Individual muscles are tightly intertwined and treatment of one anatomic region may affect many different muscles. A complete understanding of the anatomy of the upper face is essential to ensure proper injection technique, safe and predictable results as well as anticipating complications. (C) 1998 by the American Society for Dermatologic Surgery, Inc.