ORIGINAL ARTICLE Surgical Anatomy of the Face Implications for Modern Face-lift Techniques Holger G. Gassner, MD; Amir Rafii, MD; Alison Young, MD, PhD; Craig Murakami, MD; Kris S. Moe, MD; Wayne F. Larrabee Jr, MD Objective: To delineate the anatomic architecture of the were found to be located in corresponding anatomic lay- melolabial fold with surrounding structures and to elu- ers and to form a functional unit. Additional findings of cidate potential implications for face-lift techniques. the present study include the description of 3 structur- ally different portions of the melolabial fold, of an ana- Methods: A total of 100 facial halves (from 50 cadav- tomic space below the levator labii superioris alaeque nasi eric heads) were studied, including gross and micro- (sublevator space), and of extensions of the buccal fat scopic dissection and histologic findings. Laboratory find- pad into the sublevator space and the middle third of the ings were correlated with intraoperative findings in more melolabial fold. than 150 deep-plane face-lift dissections (300 facial halves) performed during the study period. Conclusions: The findings of the present study may con- tribute to augment our understanding of the complex Results: In contrast to previous reports, the superficial anatomy of the midface and melolabial fold. Potential im- musculoaponeurotic system (SMAS) was not found to plications for modern face-lift techniques are discussed. form an investing layer in the midface. The SMAS, zy- gomatici muscles, and levator labii superioris alaeque nasi Arch Facial Plast Surg. 2008;10(1):9-19 HE EVOLUTION OF COM- should be measured because complete ef- plex face-lift techniques has facement of this fold would remove this been stimulated by an in- aesthetically important landmark, which creasingly more detailed delineates the transition between the aes- understanding of the lay- thetic units of the cheek and mouth.12 Tered anatomic architecture of the face.1,2 The SMAS is the key element most face- A milestone in the development of mod- lift techniques have been designed to re- ern face-lift techniques was the descrip- position and suspend. Although the SMAS tion of the superficial musculoaponeu- is a clearly identifiable structure lateral to rotic system (SMAS) by Mitz and Peyronie3 the zygomaticus major muscle, its pres- Author Affiliations: The and the introduction of the sub-SMAS dis- ence and structure are not as well under- Larrabee Center for Facial section by Skoog.4 These modifications stood medial to this muscle. Hence, its role Plastic Surgery, Seattle, have resulted in substantial long-term im- in deep-plane face-lift dissection has not Washington (Drs Gassner, Rafii, provements of the neck and jawline. More been exactly defined. Some authors3 have and Larrabee); Division of advanced techniques followed with the described the SMAS as an investing layer Facial Plastic Surgery, purpose of better addressing the melola- that envelopes the musculature of the mid- Department of bial fold. Most noteworthy have been the face; others13,14 have described it as a sepa- Otorhinolaryngology 5 (Drs Gassner, Rafii, and contributions of Hamra as well as those rate layer that is located superficial to the 6 7 Murakami), and Department of of Baker and Kamer, who described varia- mimetic muscles and extends into the me- Dermatology (Dr Young), tions of deep-plane dissections.6-8 How- lolabial fold. Most studies present histo- Virginia Mason Hospital, ever, despite the expert execution of the logic sections of limited aspects of the mid- Seattle; and Division of Facial most sophisticated techniques, initial im- face or of the melolabial fold depicting Plastic Surgery, Department of provement of the melolabial fold has not some fibrous strands, which are desig- Otorhinolaryngology been observed to consistently persist long nated to be the SMAS. To our knowl- (Drs Gassner and Moe), term.9-11 Our current understanding of the edge, no study has been published that University of Washington, anatomy of the midface and especially the conclusively demonstrates the SMAS to be Seattle. Dr Gassner is now with the Division of Facial Plastic melolabial fold is insufficient to explain the a continuous layer spanning from the man- Surgery, Department of resistance of these areas to correction and dible or parotid fascia into the midface and Otorhinolaryngology, University to provide for a more rational approach to melolabial fold. of Regensburg, Regensburg, their surgical rejuvenation. Of course, our As is the case for the SMAS, our knowl- Germany. efforts at improving the nasolabial fold edge of the structure of the melolabial fold (REPRINTED) ARCH FACIAL PLAST SURG/ VOL 10 (NO. 1), JAN/FEB 2008 WWW.ARCHFACIAL.COM 9 ©2008 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/27/2021 Inc) at the following settings: aperture F18, shutter speed 1/60 A s, ISO 200, white balance flash, manual focus, and 70-mm fo- cal length. Microscopic photographs and video clips were obtained using an otologic microscope (model OPMI Pico; Zeiss Inc) with an attached camera (model 882 TE HDDC; Stryker Inc, Mahwah, New Jersey) and a digital recording device (model SDC Pro 2; † Stryker Inc). Photographic and video documentation was in- termittently reviewed between laboratory dissections to plan subsequent dissections. Histologic sections were obtained from 5 cadaveric heads ∗ FA (10 facial halves) from the following locations: cross-sections through the superior, middle, and inferior thirds of the me- lolabial fold; horizontal and vertical sections through the buc- cinator-SMAS fusion; horizontal sections through the modio- lus and cheek at various levels; and sections perpendicular to B the mid portion of the zygomaticus major muscle. After re- OOM S moval of the specimen, the layered architecture of the cut sur- faces was photographed for orientation and also studied using microscopic dissection techniques. The tissue sections were fixed in formalin, and paraffin embedding was performed by dehy- BSF drating the tissue blocks through ethanol and Histoclear (Na- tional Diagnostics, Atlanta, Georgia) before immersion in para- b plast (Fisher Scientific, Waltham, Massachusetts). Sections of 4 µm were stained with hematoxylin-eosin and Masson tri- chrome stains and examined under light microscopy. Histo- logic photographs were taken with a Coolscan 4000 slide scan- ner (Nikon Inc) or photomicroscope at original magnifications Figure 1. Platysma and superficial musculoaponeurotic system (SMAS) ϫ1and ϫ2.5 (Zeiss Inc). dissected off the mandible. A, From top to bottom, the 3 wooden indicators We performed more than 150 deep-plane face-lift proce- point to the platysma, the SMAS (transitioning to orbicularis oris muscle), and dures during the study period (July 1, 2006, to June 31, 2007), the inferior border of SMAS-buccinator fusion. The needle is inserted through the buccinator muscle. Asterisk, the transected mandibulocutaneous ligament; and our intraoperative observations were documented in tabu- dagger, fibers of zygomaticus major muscle radiating toward the modiolus; lated form to corroborate and verify the laboratory findings. FA, facial artery. B, Histologic cross section of the buccinator-SMAS fusion. The Intraoperative observations included the presence of the pa- “b” indicates the buccinator muscle; S, SMAS; BSF, the zone of fusion between rotid fascia after elevation of the SMAS, the absence of the SMAS buccinator muscle and the SMAS (note that the layered architecture of these 2 on the deep aspect of the malar fat pad after deep-plane dis- muscles is preserved); and OOM, orbicularis oris muscle (hematoxylin-eosin, section, the effect of deep-plane dissection and SMAS reposi- original magnification ϫ16). tioning on the melolabial fold, and the ease of dissection along the medial aspect of the deep plane with respect to the posi- is also incomplete. Despite the substantial body of lit- tion of the buccinator-SMAS fusion. erature that has emerged since Rubin’s15 landmark ar- The melolabial fold was marked and a 3-mm strip of skin ticle, many important questions regarding its micro- was preserved over the melolabial fold. The facial skin was then anatomy and relationship with surrounding structures dissected in the immediate subdermal plane and removed both remain elusive. These include the structure and posi- medially and laterally. The underlying fat was identified and tion of the fat compartments forming the melolabial bulge. inspected. The fascial insertions of the melolabial fold were then 16 followed along their lateral aspect and their relations with the Stuzin et al described various portions of the buccal fat, fat pads of the cheek, the levator labii superioris alaeque nasi including its body and buccal extension, but to our knowl- muscle, buccinator muscle, orbicularis oris muscle, zygomati- edge, no extension past the facial vessels into the me- cus major muscle, and SMAS were studied. Dissections of the lolabial fold has been described. Further remaining ques- subdermal (malar) fat pad were performed along its undersur- tions include the potential relation of the melolabial fold face in multiple directions. The relation of the SMAS to the buc- with the SMAS, its support mechanism, and their attenu- cal fat pad and retromandibular space was inspected. Medial ation with age. to the melolabial fold, the subdermal fat overlying the orbicu- laris oris and levator labii superioris alaeque nasi muscle was also removed. In the subsequent specimen, the platysma and METHODS the SMAS were elevated by inferior to superior dissection over the mandible into the midface and in a lateral to medial direc- Fifty fresh frozen cadaveric heads (100 facial halves) were dis- tion according to superficial, sub-SMAS, deep-plane, and com- sected using ϫ2.5 extended field magnifying loupes (Designs posite face-lift techniques. The relation of the SMAS to the man- for Vision, Ronkonkoma, New York) or a Pico otologic micro- dible, mandibulocutaneous ligament, infraorbital, mental and scope (Zeiss Inc, Thornwood, New York) at various magnifi- facial nerves, facial vessels, and perioral, buccinator, and zy- cations.