A Retrospective Study on Chinese-Specific Glabellar Contraction Patterns

BACKGROUND Botulinum toxin has been widely accepted as safe and effective for the treatment of glabellar lines, and previous studies have classified glabellar contraction patterns into 5 categories. OBJECTIVE To classify the glabellar contraction patterns among large-scale Chinese population and provide reference for injections in Chinese patients. METHODS Four hundred eighty-nine Chinese subjects who received botulinum toxin for the treatment of glabellar lines were selected for a retrospective photographic analysis of their glabellar contraction patterns. Using 2 separate previously established classification systems, the patterns were analyzed and classified by a panel of certified Chinese dermatologists. RESULTS Two separate classification systems showed different distributions of glabellar contraction patterns among Chinese compared with Caucasians and Koreans. The classifications allowed for identification of the most frequent patterns in Chinese, which were "converging arrows" and "11" pattern, and provided references for identifying the most important muscles. CONCLUSION Both classification systems are applicable to the Chinese population with varying distributions. Because the classification system of de Almeida and colleagues focuses more on the muscles involved in the formation of glabellar lines, the authors' subjects classified according to this system displayed a more balanced distribution among the 5 patterns. This provides an easier reference for dermatologists in daily clinical practice and guiding treatment strategies. This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal. Address correspondence and reprint requests to: Yan Wu, MD, PhD, Department of Dermatology, Peking University First Hospital, No. 8 Xishiku Street, Xicheng District, Beijing, China, or e-mail: 3437477565@qq.com The authors have indicated no significant interest with commercial supporters. D.M.-Y. Hsieh and S. Zhong contributed equally to this work. © 2019 by the American Society for Dermatologic Surgery, Inc. Published by Wolters Kluwer Health, Inc. All rights reserved.

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