You are in: eMedicine Specialties > Otolaryngology and Facial Plastic Surgery > COSMETIC SURGERY Facelift AnatomyArticle Last Updated: May 20, 2008AUTHOR AND EDITOR INFORMATIONSection 1 of 11
 
Author: S Valentine Fernandes, MBBS, MB, BS, BSc(Hons), MCPS, FRCSEd, FRACS, FACS, Conjoint Senior Clinical Lecturer, Department of Otorhinolaryngology, Newcastle University; Senior Consultant Surgeon, Department of Otorhinolaryngology-Head and Neck Surgery, John Hunter, Toronto Private and Kurri Hospitals, Australia S Valentine Fernandes is a member of the following medical societies: American Academy of Facial Plastic and Reconstructive Surgery, American Academy of Otolaryngology-Head and Neck Surgery, and American College of Surgeons Editors: J David Kriet, MD, FACS, Associate Professor, Department of Otolaryngology-Head and Neck Surgery, Director of Facial Plastic and Reconstructive Surgery, University of Kansas School of Medicine; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Keith A LaFerriere, MD, Clinical Professor, Fellowship Director, Department of Surgery, Division of Otolaryngology, University of Missouri at Columbia; Christopher L Slack, MD, Otolaryngology-Facial Plastic Surgery, Private Practice, Associated Coastal ENT; Medical Director, Treasure Coast Sleep Disorders; Arlen D Meyers, MD, MBA, Professor, Department of Otolaryngology-Head and Neck Surgery, University of Colorado School of Medicine Author and Editor Disclosure Synonyms and related keywords: facelift anatomy, face lift, face-lift, anatomy of the face, face anatomy, facial anatomy, facial nerve injury, great auricular nerve damage, superficial musculoaponeurotic system, SMAS, facial plastic surgery anatomy, facial surgery anatomy INTRODUCTION, HISTORY, AGING CHANGES, AND SURFACE ANATOMYSection 2 of 11
 
Introduction History The initial classic subcutaneous dissection and excision of redundant skin was the obvious answer to ailing skin elasticity. However, the results were not durable; thus, the search for techniques to produce longer lasting and better results began. In 1976, the work of Mitz and Peyronie provided a sound anatomic basis to Tord Skoog's "useful technique," which was revealed in 1969.1, 2 Hamra carried facelifting techniques further, involving deeper planes; improved techniques of craniofacial reconstruction have led to facelifting on the subperiosteal plane.3 Aging changes The accepted younger contours of the face and neck are lost and the mimetic function is diminished as a result of interaction between fixed points and the attenuation in skin and subjacent tissue elasticity.2 This is analogous to the laxity of a carpet after years of use. The concrete foundation of the floor has carpet overlaid on underlay. Laxity of the carpet may be addressed by trimming the carpet at the edges. However, longer-lasting results may be obtained by attending to the underlay at the same time. This analogy relates bone as the concrete foundation, the superficial musculoaponeurotic system (SMAS) layer as the underlay, and skin as the carpet. Incidentally, moving the furniture individually is much easier than dragging it with the carpet, except that in the face, the "furniture" is on the undersurface. Surface anatomy The face is divisible horizontally into thirds. The upper third extends from the hairline to the eyebrows, the middle third extends to the subnasale, and the lower third extends to the chin. Vertical subdivision into a central mimetic zone and a lateral masticatory zone is possible. The boundary lies at the anterior border of the masseter muscle. Initial attempts at facelifting involved tightening the masticatory zone to influence the mimetic zone. In the mimetic zone, medial to the nasolabial fold, the mimetic muscles are firmly attached to the skin; hence, the effects of gravitational aging are less here than in the zone lateral to the fold. SKIN, SUBCUTANEOUS FASCIA, AND MALAR FAT PADSection 3 of 11
Skin The epidermis is composed of 5 termed layers that become flatter toward the surface. It protects the dermis, which contains the surface blood vessels, lymphatics, and nerves. Pigmentation is produced by the melanocytes from tyrosine, and dnexal glands provide moisture and moisture protection. Various muscles may insert into the skin to produce surface movement and mimetic function. In some individuals, attachment of the superficial musculoaponeurotic system (SMAS) layer to the skin causes dimpling in certain areas. The skin of the face is generally thinner than skin elsewhere, with the the thinnest skin being located on the upper eyelid. Beveling the incision in haired skin is important to minimize trauma to the hair follicles. In the posterior cervical and infra-aural region that overlies the sternocleidomastoid muscle, the skin is adherent to the underlying tissues and may be buttonholed if caution is not exercised. Some authors refer to this as a platysma-auricular ligament. The fibers of thegreat auricular nerve are in the immediate vicinity. Subcutaneous fascia The subcutaneous fascia is not really a fascial layer in the true sense. This panniculus adiposus layer in the face is well developed in well-nourished individuals. Nerves, blood vessels, and lymphatics form the subdermal plexus in this layer before supplying the skin. Dissection in this layer traumatizes the subdermal plexus and may lead to hematoma formation. Malar fat pad The malar fat pad (see Image 9) lies superficial to the SMAS and overlies the orbicularis oculi, zygomatici, and levator muscles. It is adherent to the skin, and the zygomatic ligaments traverse it. For efficient placement, dissection must proceed between the muscles and the fat pad so that it remains attached to the skin. SUPERFICIAL MUSCULOAPONEUROTIC SYSTEM AND PAROTIDEOMASSETERIC FASCIASection 4 of 11
Superficial musculoaponeurotic system One end of the muscle in the panniculus carnosus layer is attached to skin, and the other end is attached to deep fascia or bone. This sheet is well developed in the scalp and face and includes the occipitofrontalis muscle with the intervening galea, the orbicularis oculi muscle, the temporoparietal fascia, the superficial musculoaponeurotic system (SMAS) layer of the cheek (which is interpreted by some as the flattened aponeurosis of the platysma), and the platysma muscle. In fact, the SMAS layer (see Image 1) may be composed of 2 layers, investing the platysma muscle, orbicularis oculi muscle, occipitofrontalis muscle, zygomatici muscles, levator labii superioris muscle, temporal branches of the facial nerve, superficial temporal vessels, and the accompanying auriculotemporal nerve. In the temporal and retroauricular regions, this temporoparietal fascia layer (as it is called here) may sometimes be encountered in 2 layers. Also, the temporal fascia splits into 2 layers below the level of the superior orbital margin to enclose the superficial fat pad. In these circumstances, if one proceeds anteriorly under the first layer in a subtemporoparietal fascia dissection, mistaking the deeper layer to be the temporal fascia, trauma to the frontal division of the temporal branch of the facial nerve may occur. Hence, incision to the temporalis muscle is advisable to confirm and accept the layer above it as the temporal fascia, which is much thicker than the temporoparietal fascia layers. The SMAS may be more distinct toward the zygomaticus major muscle. Realistically, the SMAS is a fibromuscular layer that is thicker and attached to the underlying fascia over the proximal masticatory zone and thinner and more separable from the underlying fascia over the distal masticatory zone. Hence, proceeding sub-SMAS about 2-3 cm anterior to the pretragal crease is advisable. This maneuver also lends skin support to the distal SMAS and skin flap because the SMAS layer may be much thinner and variable in tensile strength further forward. Some authors claim to trace the SMAS layer medial to the nasolabial fold, deep to a fascial-fatty layer, and attaching to the superficial portion of the orbicularis oris, which is claimed to be an embryologic continuation of the SMAS layer. Parotideomasseteric fascia The deep (investing) layer splits into 2 layers to invest the parotid gland. The layer passing deep to the parotid gland is attached superiorly along the base of the skull from the tip of the mastoid process to the lower border of the tympanic plate, as far medially as the carotid foramen. Anteriorly, the fascia continues deep to the masticatory (buccal) fat pad. The superficial layer over the parotid gland is termed the parotid fascia, and it attaches superiorly to the zygomatic process of the temporal bone. The upward continuation is the temporal fascia. With the exception of the temporal branches, the other facial nerve branches lie deep to this layer further anterior in the cheek, in the part known as the parotideomasseteric fascia. This thin layer may be separated from the overlying SMAS between the anterior border of the parotid gland and the anterior border of the masseter muscle. RETAINING LIGAMENTS AND FOLDSSection 5 of 11
Retaining ligaments The retaining ligaments, which may have teleologic significance, hamper advancement of the skin flap. They may be osteocutaneous or musculocutaneous and insert into the dermis. McGregor first described the zygomatic osteofasciocutaneous ligaments and their role in impairing full mobility of the skin flap. These ligaments anchor the skin to the inferior border of the zygomatic arch contribution from the zygomatic bone. The term zygoma should be used only to refer to the zygomatic process of the temporal bone. The zygomatic ligaments extend through the malar fat pad, suspending it over the eminence. Accompanying the ligaments are an artery and a sensory nerve. Immediately deep to the ligaments lies a zygomatic branch of the facial nerve. Therefore, exercise care to identify these ligaments prior to their incision. With age, these ligaments become lax, leading to inferomedial migration of the malar fat pad and formation of the nasolabial fold. The osseocutaneous mandibular ligament arises from the mandibular parasymphysis and inserts into the skin inferior to the insertion of the depressor anguli oris, interdigitating with the platysma, which lies deeper to the depressor. If this ligament is left intact and employed as an anchor to allow the jowl lift to pull against it, the perioral area assumes a much more natural look postoperatively. The fasciocutaneous masseteric ligaments pass from the region of the anterior border of the masseter muscle toward the dermis. They may represent the points of fusion between the superficial musculoaponeurotic system (SMAS) and the parotideomasseteric fascia layers. With age, laxity of the masseteric ligaments allows the inferomedial descent of the tissues and contributes to the formation of the labiomandibular fold or jowl. The anterior limit of the jowl is the mandibular ligament. The masseteric ligaments need to be freed to achieve skin advancement during facelifting. The masseteric ligament also approximates the midcheek furrow of aging and the posterior boundary of the mimetic muscles. Nasolabial and other folds The cutaneous insertion of the zygomatic muscles (ie, levator labii superioris and levator labii anguli oris) determines the nasolabial crease. Histologically, the nasolabial crease is composed of a fibrous fold with attachments from the zygomatici and levators. In a sense, the nasolabial crease may be considered a fasciocutaneous ligament where the SMAS and deep fascia are united, with some attachments from these muscles. Muscle fibers from this fibrous fold accompany these muscles further through the orbicularis oris muscle to insert into the dermis. Apparently, the muscle fibers that arise from the fold, along with the lip elevators, initiate the smile, which is further completed by the zygomatici and levators. Laxity of the zygomatic ligaments causes the malar fat pad to travel inferomedially over the crease to produce the nasolabial fold. The depressor anguli oris superiorly and the mandibular ligaments inferiorly determine the labiomandibular crease, which similarly is converted into a fold as a result of the laxity of the masseteric ligaments that occurs with age. FACIAL AND OTHER NERVES AND FACIAL MUSCLESSection 6 of 11
Facial nerve The facial nerve in its initial extratemporal passage lies deep to the superficial lobe of the parotid gland and is thus protected from injury during facelifting in this part of its course. At the superior, anterior, and inferior borders of the gland, the nerve emerges in several branches (eg, temporal, zygomatic, buccal, marginal mandibular, cervical; see Images 2-3, Image 5, Images 7-8). In the sagittal-coronal plane, the branches assume a superolateral-to-inferomedial position with the superior temporal branches lying in the superficial musculoaponeurotic system (SMAS) fascia and the lower branches lying deep to the parotideomasseteric (ie, superficial layer of deep investing) fascia. As many as 5 temporal branches, which lie anteroinferior to the superficial temporal vessels, may be present. These branches cross the zygomatic arch at least 1 cm anterior to the auriculotemporal crease. The frontal division of the temporal branches of the facial nerve may be approximated by a line 0.5 cm below the tragus to 1.5 cm lateral to the eyebrow. The sentinel (zygomaticotemporal) vein, which is a tributary of the pterygoid plexus, lies lateral to the frontozygomatic suture line. The nerve lies cephalad to the sentinel vein. Exercise caution around this area to avoid denervation to the frontalis and allied muscles. If dissection extends deep to the zygomatic muscles, the zygomatic branches (usually 2) are encountered, and a risk of trauma occurs. A branch superficial to the zygomaticus major muscle that innervates the orbicularis oculi muscle is described, but the latter muscle is also supplied by frontotemporal branches. Hence, trauma to this branch is largely unnoticed as a result of the dual nerve supply. The buccal branches (usually 2) are easily seen lying over the masseter muscle deep to the parotideomasseteric fascia. The marginal mandibular branch of the facial nerve usually emerges from the parotid gland about 1 cm below the angle of the mandible. It lies deep to the SMAS (platysma muscle) and the parotideomasseteric fascia and posterior to the facial vessels. However, it usually ascends back into the face anterior to these vessels. This branch may be seen during facelifting, but particular care should be exercised while achieving hemostasis around the facial vessels because the nerve may be traumatized with such attempts. Occasionally, 2 marginal mandibular branches are present. The cervical branch lies underneath the platysma muscle and penetrates this muscle about 2 cm below the mandible. Some authors claim that these extraparotid facial nerve branches communicate at least 4 times before supply. Operative experience suggests that at least some of this arborization occurs, particularly in the buccal branch distribution. The great auricular nerve lies deep to the superficial layer of the investing deep fascia as it ascends vertically over the sternocleidomastoid muscle. It lies either in contact or some distance posterior to the external jugular vein, and it divides into anterior and posterior branches to supply the periauricular region. The great auricular nerve is subject to trauma during subcutaneous lifting in the infra-aural region. It may be damaged during dissection over the sternocleidomastoid muscle because it is located 6 cm below the tragus at the anterior margin of the muscle to 9.5 cm below the tragus at the posterior margin of the muscle. The infraorbital nerve deserves attention during subperiosteal lifting in the region of the cheek via an intraoral approach. The nerve emerges from the infraorbital foramen, sandwiched between the superficial surface of the levator anguli oris and the deep surface of the levator labii superioris muscles, to provide sensory innervation to the cheek and lip. The mental nerve emerges from the mental foramen, which lies below the second mandibular premolar. This nerve is vulnerable to injury during chin surgery. Facial muscles The muscles and SMAS of the upper face are derived from the sphincter colli profundus. Unlike the lower face segments, which are derived from the primitive platysma, the upper face SMAS and muscles have bony insertions. The junction of the 2 divisions lies at the lateral border of the zygomaticus muscle. Hence, freeing the SMAS at this point allows better advancement of the SMAS-skin flap. Apart from their mimetic function, the facial muscles provide sphincteric support to the ocular, nasal, and oral orifices. The orbicularis oculi muscle is divisible into 2 main parts. The palpebral part overlying the lids arises from the medial palpebral ligament and inserts into the lateral palpebral raphe. Some authorities further subdivide the palpebral part into preseptal and pretarsal parts. The orbital part overlying bone arises from the anterior lacrimal crest and maxilla and encircles the eye in concentric loops. The nasal muscles arise from the maxilla; they are the compressor nares, which overlie the alar cartilages, and the dilator nares, which are inserted in the lateral part of the ala of the nose. The orbicularis oris is the only sphincter muscle of the mouth. The other muscles provide dilator function. The buccinator and other circumoral muscles also contribute to the orbicularis oris muscle. The levator labii superioris alaeque nasi arises from the frontal process of the maxilla and inserts into the ala of the nose and upper lip. The levator labii superioris arises from the maxilla superior to the infraorbital foramen and inserts into the upper lip. Below the infraorbital foramen arises the levator anguli oris. The zygomaticus minor arises from the zygomaticomaxillary suture, and the zygomaticus major (see Image 4) originates further laterally on the zygomatic bone (about 5 cm from the auriculotemporal crease); both muscles converge on the modiolus. The risorius muscle also converges on the modiolus when present. The depressor anguli oris lies superficial to the depressor labii inferioris, arising from the oblique line of the mandible. The mentalis muscle arises from the symphysis menti and penetrates the depressor labii inferioris to insert into the skin. The paired platysma muscle originates from the clavicles and first ribs. The medial edges are separated inferiorly but may decussate above the thyroid cartilage to insert into the modiolus. The mentalis, levator anguli oris, and buccinator lie deep to the plane of the facial nerve and derive their motor supply on their superficial surface. The facial vessels also adhere to this plane. lying superficial to the aforementioned muscles. All other muscles lie superficial to this plane and are supplied on their deep surface. Singularity in the mimetic function in each individual depends on the number and degree of development of each muscle and their attachments to bone, SMAS, and dermis in various combinations. BUCCAL FAT PAD, PAROTID GLAND AND DUCT, AND VASCULAR SUPPLYSection 7 of 11
Buccal fat pad Buccal fat pad is a misnomer, because it is actually a specialized type of fat that facilitates intermuscular motion. It should be termed the masticatory fat pad, because it lies in the masticatory space associated with the muscles of mastication. It extends laterally over the masseter and buccinator muscles, deep to the plane of the parotid duct and facial nerve branches, and extends anteriorly to the facial vessels. Medially, it may reach into the pterygopalatine space, and an extension lies superficial to the temporalis muscle and its tendon is separated from the superficial fat pad by the deeper layer of temporal fascia. Parotid gland and duct Invested between the layers of the deep (investing) fascia, this serous salivary gland lies wedged between the mastoid process and the posterior border of the mandible, and it extends forward over the masseter muscle. Its anterior border is convex forward. From it emerge the parotid duct and branches of the facial nerve lying deep to the forward extension of parotid fascia known as the parotideomasseteric fascia. The duct passes forward across the masseter muscle and turns around its anterior border to pierce the buccinator muscle. The duct and facial nerve branches lie superficial to the buccal fat pad. If an accessory lobe is large, it may extend forward to or even under the zygomaticus major muscle. Vascular supply The vascular supply to the face arises from the facial vessels medially and from the superficial temporal vessels laterally. These arteries originate from the external carotid. The facial veins drain into the internal jugular vein, and the superficial temporal veins eventually drain into both the internal and external jugular veins. The supraorbital and supratrochlear branches from the internal carotid system supply the forehead (see Image 6). The generated angular vein joins the facial vein. Medially, the musculocutaneous branches of the facial artery contribute to the subdermal plexus. Laterally, the fasciocutaneous branches of the superficial temporal artery (see Image 10) and the transverse facial artery contribute to the subdermal plexus. These medial and lateral vessels approximate each other lateral to the nasolabial fold. Sub-superficial musculoaponeurotic system (SMAS) dissection transects the lateral perforators, placing supply of the flap solely on the medial musculocutaneous vessels. Subcutaneous dissection transects the subdermal plexus. Both the subcutaneous and sub-SMAS flaps are random patterned, based on several vessels with varying patterns of supply dominance. FOREHEAD AND TEMPORAL REGIONSSection 8 of 11
Forehead region The layers in the forehead and scalp region include the skin, the subcutaneous fat layer, the galea, a loose areolar layer, and the periosteum. The galea, which is a superficial musculoaponeurotic system (SMAS) equivalent, incorporates the paired frontalis muscles and continues laterally to become the temporoparietal fascia. The frontalis muscle inserts at the medial supraorbital rim into the upper part of the orbicularis oculi muscle and overlying skin. The paired corrugator muscles arising from the periosteum at the superomedial aspect of the orbital rim lie deeper and insert with the frontalis and orbicularis oculi into the skin laterally. The supratrochlear nerves may penetrate the corrugator muscle to emerge on the deep surface of the frontalis muscle. Damage to the nerve may occur at this point during corrugator resection. The procerus muscle lies medial and ventral to the corrugator muscles, arising from the nasal bones and upper lateral cartilages and inserting into the skin between the eyebrows. The supraorbital nerve and vessels emerge from the supraorbital notch or canal and continue cephalad in the galea. Occasionally, this neurovascular bundle may exit from a foramen cephalad to the orbital rim, demanding caution with blind dissection within 2 cm of the supraorbital rim. Temporal region The layers of the temporal region are the skin, subcutaneous fat, temporoparietal fascia (which is the equivalent of the SMAS layer), temporal fascia, and the temporalis muscle. The temporal fascia overlying the muscle splits into 2 layers, enclosing the superficial fat pad before reuniting about 1 cm above the superior margin of the zygomatic arch and fusing with the parotideomasseteric fascia below. The deep fat pat is an extension of the masticatory fat pad of Bichat and lies deep to the deeper layer of temporal fascia. The frontal division of the temporal branches of the facial nerve lies in the temporoparietal fascia and is at risk at the level of the zygomatic arch in a subperiosteal facelift operation. Hence, the dissection is carried deep to the temporoparietal fascia until about 3 cm above the zygomatic arch, when it is deepened through both layers of temporal fascia into the deep fat pad and continued toward the zygomatic arch. At this point, the deeper layer of temporal fascia and zygomatic periosteum is incised anteriorly, and the dissection then proceeds subperiosteally to the superficial surface of the bony zygomatic arch. PLANES OF FACELIFT, DANGER ZONES, AND CONCLUSIONSection 9 of 11
Planes of facelift In the quest for the perfect facelift technique, combinations of dissections at various levels or planes have been used. These include the following:
Danger and care zones
Conclusion Until surgeons all understand the anatomic basis for the changes of aging, various techniques to improve segments of the whole will continue to be propounded. Also, the concept of beauty must be differentiated from the concept of aging. Whereas beauty is concerned mainly with the introduction of harmony, aging is mainly concerned with loss of elasticity. However, when the skin is tightened, an improvement is noted. The amount and duration of improvement depend on the technique used, and this depends on the surgeon's understanding of the anatomic basis of the changes of aging. More extensive dissections are associated with more potential for damage. A knowledge of applied anatomy aids in avoiding the associated complications. MULTIMEDIASection 10 of 11
REFERENCESSection 11 of 11
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