COSMETIC Anatomy of the Corrugator Supercilii Muscle: Part I. Corrugator Topography Jeffrey E. Janis, M.D. Ashkan Ghavami, M.D. Joshua A. Lemmon, M.D. Jason E. Leedy, M.D. Bahman Guyuron, M.D. Dallas, Texas; and Cleveland, Ohio Background: Complete corrugator supercilii muscle resection is important for the surgical treatment of migraine headaches and may help prevent postoper- ative abnormalities in surgical forehead rejuvenation. Specific topographic anal- ysis of corrugator supercilii muscle dimensions and its detailed association with the supraorbital nerve branching patterns has not been thoroughly delineated. Part I of this two-part study aims to define corrugator supercilii muscle topog- raphy with respect to external bony landmarks. Methods: Twenty-five fresh cadaver heads (50 corrugator supercilii muscles and 50 supraorbital nerves) were dissected to isolate the corrugator supercilii muscle from surrounding muscles. Standardized measurements of corruga- tor supercilii muscle dimensions were taken with respect to the nasion and lateral orbital rim. Results: Relative to the nasion, the most medial origin of the corrugator supercilii muscle was found at 2.9  1.0 mm; the most lateral origin point, 14.0  2.8 mm. The lateralmost insertion of the corrugator supercilii muscle measured 43.3  2.9 mm from the nasion or 7.6  2.7 mm medial to the lateral orbital rim. The most cephalic extent (apex) of the muscle was located 32.6  3.1 mm cephalad to the nasion–lateral orbital rim plane and 18.0  3.7 mm medial to the lateral orbital rim. There were no statistical differences noted between the right and left sides. Conclusions: The dimensions of the corrugator supercilii muscle are more extensive than previously described and can be easily delineated using fixed bony landmarks. These data may prove beneficial in performing safe, com- plete, and symmetric corrugator supercilii muscle resection for forehead rejuvenation and for effective decompression of the supraorbital nerve and supratrochlear nerve branches in the surgical treatment of migraine headaches. (Plast. Reconstr. Surg. 120: 1647, 2007.) C omplete resection of the corrugator super- cilii muscle has been advocated for both forehead rejuvenation and in the surgical treatment of migraine headaches. 1–3 Unequal corrugator supercilii muscle removal and/or in- complete corrugator supercilii muscle resection after forehead rejuvenation can lead to undesir- able sequelae such as dimpling, depressions, and residual corrugator activity, with resultant persis- tence of dynamic rhytides. 1–3 All of these may become exaggerated on forehead animation. 1,4,5 The cause of this may be related to the surgical approach, specific technical execution, and/or the surgeon’s experience with a particular technique. 1,6,7 In a recent study, Walden et al. 6 have shown that the amount of corrugator supercilii muscle resec- tion can vary depending on the approach used, with as much as one-third of the transverse corru- gator supercilii muscle head remaining after trans- palpebral attempts at complete muscle removal. Although the senior author (B.G.) believes that this may largely be technique-related, 7,8 familiarity with normal corrugator supercilii muscle dimen- sions in reference to fixed bony landmarks can minimize this unpredictability and allow for a more systematic approach to precise corrugator supercilii muscle myectomy. In addition, a compre- hensive understanding of the corrugator supercilii From the Department of Plastic Surgery, The University of Texas Southwestern Medical Center, and the Department of Plastic and Reconstructive Surgery, Case Western Reserve University School of Medicine. Received for publication April 13, 2006; accepted September 7, 2006. Gaspar W. Anastasi Award presentation at the American Society for Aesthetic Plastic Surgery Annual Meeting, in Orlando, Florida, April 23, 2006. Copyright ©2007 by the American Society of Plastic Surgeons DOI: 10.1097/01.prs.0000282725.61640.e1 www.PRSJournal.com 1647