SMAS Facelift Rhytidectomy 

Updated: Oct 31, 2018
Author: Andrew Jacono, MD; Chief Editor: Arlen D Meyers, MD, MBA 

Overview

Background

Patients who seek consultation for rhytidectomy are concerned about the aging of their facial features. These features include sagging cheeks, jowl, and buccolabial folds and redundant and bulky submental and cervical tissues.[1] The goal of the facial plastic surgeon is to determine the characteristics that are contributing to the patient's aging appearance and which of the characteristics are reversible. A comprehensive approach to the aging face may include endoscopic brow and/or midface lifting, blepharoplasty, chin and malar implantation, and chemical/laser exfoliation in addition to rhytidectomy. This article focuses on superficial musculoaponeurotic system (SMAS) rhytidectomy.[2, 3, 4]

The image below depicts the pictures of a woman before and after rhytidectomy.

Before and after biplanar face lift with lower eye Before and after biplanar face lift with lower eyelid blepharoplasty and chin augmentation.

The ideal rhytidectomy candidate is a middle-aged woman with a fair or medium complexion and a minimal amount of adipose tissue and moderate skin laxity in the jowl and cervicomental regions. An individual with a strong, attractive underlying osseous framework, including prominent zygomatic arches, obtains even further enhancement. Conversely, an individual who is overweight with hyperpigmented thick skin does not obtain optimal results. Individuals with ptotic submandibular glands and an inferiorly positioned hyoid have a more obtuse cervicomental angle and obtain less-than-optimal results.

In 2014, according to the American Society of Plastic Surgeons, 128,266 facelifts were performed in the United States, making it one of the top five cosmetic surgical procedures performed (along with breast augmentation, blepharoplasty, liposuction, and rhinoplasty). Female patients accounted for the majority of facelifts (116,415).[5]

For further reading, please see Medscape's resource center on aesthetic medicine.

Etiology

See the list below:

  • Aging is characterized by tissue atrophy and reduction in skin's cellular and protein components.

  • Gravitational redistribution of soft tissues occurs.

  • Sun exposure contributes to the clinical changes observed in the aging face.

Pathophysiology

Histologically, the skin epidermis thins with retraction of the rete pegs. Decreasing numbers of melanocytes create areas of uneven pigmentary changes. In the dermis, elastic filaments become thin and fragmented, increasing skin laxity. Dermal collagen becomes more biochemically stable, but it is reduced in quantity. Vascular supply is also reduced, resulting in a pale appearance.

Subcutaneous tissues undergo fat atrophy with gravitational redistribution of soft tissues. With skin laxity, whole regions of the facial skin begin to sag and loosen. Habitual facial expressions can lead to progressive recontouring of the subcutaneous layer, and, hence, coarse wrinkles and deep folds develop.

Age-related changes in bone density also affect the facial skeleton. Loss of bone mass in the mandible, maxilla, and frontal bones induce increased sagging of the forehead and facial skin. This process contributes to the perception of a sagging neckline and the occurrence of jowling along the mandible with a loss of a clear delineation between the jaw line and the neck.

Sun exposure contributes to the clinical changes observed in the aging face. Sun-damaged epidermis is characterized by a reduction in structural elements that leads to skin wrinkling. Elastic fibers grow thickened and disorganized, a process called elastosis, and dermal collagen becomes degenerated.

Indications

The main surgical criterion is whether a technically sound rhytidectomy can change the individual's appearance to a more youthful one. The benefits of a rhytidectomy are limited to tightening and resupporting the tissues of the lower two thirds of the face. These include the jowl, submentum, anterior neck, and, depending on the face-lifting technique, malar tissues. If brow ptosis or excess eyelid skin is contributing to the individual's aging appearance, a brow lift or blepharoplasty is required to produce the desired result.[6]

In addition to cervicofacial skin ptosis, aging brings about other changes. Fine lines and deeply etched wrinkles are problems not well addressed by rhytidectomy. They require ancillary procedures, including chemical and laser exfoliation. The nasolabial fold is not affected by a traditional SMAS facelift; the patient must understand this prior to surgery, and options such as endoscopic midface lifting and deep plane facelifting can be discussed with the patient.[7] Discussion of these 2 procedures is beyond the scope of this article. Geniomandibular grooves are similarly not corrected by facelifting. Again, special procedures or implants may be necessary for correction; surgical planning to treat this problem may include pre-jowl chin implants or autologous fat injections. However, a new technique has been studied for filling deep nasolabial folds with SMAS tissue.[8]

The overall improvement possible with rhytidectomy is limited by aging of the upper third of the face and eyelids and the presence of wrinkles. When these problems are not addressed, suboptimal results are obtained, leaving half the face appearing aged. The underlying structure of the face is also critical because the redraping of the skin from the facelift highlights attractive cheekbones, chin, and jaw line. A relatively high and posterior hyoid is ideal, allowing maximal elevation of the submental contour.

Patients with rounder faces, low cheekbones, short mandibles, and ptotic submandibular glands have limited cervicofacial definition with rhytidectomy alone. With these patients, adjunctive cheek and chin implantation may be necessary to provide the desired result. Patients with a small chin or inferiorly placed hyoid cannot achieve the desired cervicomental definition without a chin implant.

Relevant Anatomy

The authors use a 2-layer cervicofacial rhytidectomy with suspension of the superficial musculoaponeurotic system (SMAS). The SMAS fascia is a fanlike fascia that envelops the face and is used to resuspend sagging facial tissues. The SMAS is continuous with the platysma muscle inferiorly and the superficial temporal fascia superiorly, and it is superficial to the parotid fascia. The SMAS connects to the fascial musculature in the nasolabial, perioral, and periorbital regions.

Facial nerve branches that exit the parotid gland are deep to the SMAS. The frontal branch of the facial nerve is deep to the superficial temporal fascia. Therefore, to avoid injury, the plane of dissection should not be as deep as the temporal fascia.

Contraindications

Age alone should not be used as a criterion to deny a patient surgery because patients in the eighth and ninth decades of life can enjoy up to another 15 years of life. Absolute contraindications include bleeding diatheses and American Society of Anesthesiologists (ASA) classes IV and V. Strong relative contraindications include patients with diseases predisposing to poor wound healing, ie, those with diabetes mellitus, those on long-term steroid therapy, or those with connective-tissue disorders such as Ehlers-Danlos syndrome.

A history of smoking is relevant to preoperative assessment. Rees and Aston noted that people who smoke have 12 times more risk of skin slough than people who do not smoke do. Patients who smoke also have a higher risk of hematoma formation. These effects are believed to be due to increased vasoconstriction and coughing in smokers, respectively. If the patient stops smoking for 1 month before and after surgery, these complications can be limited.

Psychological assessment is as important as the patient's medical status. The surgeon must determine patient motivation and must ascertain whether the patient has reasonable expectations for the surgical outcome. Any psychiatric illness that involves a distorted perception of reality, such as schizophrenia, should be a contraindication to surgery. If any question exists as to whether a patient has a psychiatric illness that may impact the surgical plan, a psychiatric consult is required.

 

Workup

Laboratory Studies

Any history of bleeding diatheses mandates a full workup, including the following:

  • Platelet count

  • Bleeding time

  • Prothrombin and activated partial thromboplastin time

 

Treatment

Preoperative Details

A comprehensive evaluation of the facial nerve and muscles is performed to note any asymmetries in the mouth and brow. Asymmetries in the soft tissues, scars, or surface irregularities are noted and discussed with the patient prior to surgery.

Patients with diabetes mellitus or hepatic, cardiovascular, renal, or thyroid disorders must have their metabolic state stabilized preoperatively because these conditions may impact wound healing and hematoma formation. A history of anticoagulant use (including warfarin [Coumadin] and nonsteroidal anti-inflammatory medications such as aspirin and ibuprofen) is critical. Use of these medications must be discontinued at least 1 week prior to surgery to prevent excessive bleeding and hematoma formation. Vitamin E intake in excess of 400 IU per day should also be discouraged. Other herbal therapies, including Ginkgo Biloba, should be avoided.

Past history of Bell palsy is significant. If positive, the patient should be informed that recurrence is possible postoperatively.

Intraoperative Details

The patient is marked in the upright position to outline submental liposis, vertical platysmal banding, and the region of jowl formation. Other landmarks that are outlined include the anterior border of the sternocleidomastoid muscle and the angle of the mandible. Patanguay's line is marked, noting the path of the frontal branch of the facial nerve; it is a straight line from just beneath the earlobe to 1.5 cm above the lateral aspect of the eyebrow. A line 2.5 cm from the oral commissure and lateral canthus is marked as the most medial aspect of the skin dissection to ensue.

The incision is made in the temporal hair-bearing skin in a line that continues into the skin anterior to the root of the helix. From here, the incision curves just behind the tragus, thereby partially hiding the incision, and it emerges in the skin anterior to the ear lobule to cure behind the ear lobule and into the postauricular and occipital skin. The authors use a high postauricular incision, which is best to hide the incision. In the male patient, preauricular incisions are preferred to prevent hair growth in the external auditory canal observed in posttragal incisions.

The skin flap is elevated in the occipital region sharply with the scissors tips pointing upward. The skin may be densely adherent in the area of the sternocleidomastoid fascia. Meticulous dissection in this area prevents damage to the greater auricular nerve. Dissection continues anteriorly with the complete freeing of the ear lobe. Dissection then continues in a superior direction. Superficial flap elevation in the area of the zygoma prevents damage to the frontal branch of the facial nerve. Dense osseocutaneous ligaments in the malar region make flap elevation more tedious. The skin flap is elevated to the previously noted mark from the oral commissure and lateral canthus and from one side of the neck under the chin to the other side.

Once the skin flap is elevated, the SMAS is incised preauricularly, and a SMAS flap is elevated by blunt dissection to the anterior border of the parotid gland and inferiorly to the junction of the platysma. Once at the edge of the parotid gland, blunt dissection is continued over the masseter superficial to the facial nerves. This degree of dissection is warranted in patients with more severe jowling. After redraping the SMAS layer, the excess SMAS is excised. The SMAS is then resuspended using a 3-0 Ethibond suture.

See the image below of a biplanar face lift surgery in progress.

Intraoperative photograph of biplanar face lift wi Intraoperative photograph of biplanar face lift with skin flap and extended SMAS flap elevated.

The first suspension vector runs from the angle of the mandible and sternocleidomastoid in the direction of the mastoid, and the second tightens the periparotid SMAS upward toward the tragus. The overall pull is superior and partially posterior.

A submental incision can be made to plicate the medial ends of the platysma if vertical banding is present in the neck. When combined with lateral platysmal tightening, a corset is created and submental contour is further improved.

A closed suction drain is used to decrease the risk of hematoma formation. The postauricular flap and temporal region are trimmed, and the skin is reapproximated with skin staples. Otherwise, the non–hair-bearing skin is reapproximated with a 5-0 nylon sutures in an interrupted fashion, paying attention to wound end eversion. Creation of a hemostatic net has also been shown to prevent hematoma in a study of 405 patients.[9]

In a retrospective study, Rosenfield evaluated the use of a solely lateral, “low” SMAS technique in place of the midline open neck lift employed in association with SMAS rhytidectomy. Full correction of neck deformities in the study’s 198 patients was reported, with faster recovery times achieved than with traditional direct neck lifts.[10]

Postoperative Details

Postoperatively, methylprednisolone (Medrol) is prescribed, as well as high-dose vitamin C therapy (1000 mg TID) and Arnica Montana and bromelain therapy. This helps minimize bruising and swelling. Prophylactic antibiotics, usually cephalexin (Keflex), are also prescribed.

Complications

The major complications following facelift surgery include hematoma, nerve injury, and incisional problems. Complications are related to the extent of the surgery and degree of hemostasis.

Hematomas are the most common complication and occur in as many as 8.5% of cases. An expanding hematoma is a surgical emergency that requires immediate operative intervention. If unrecognized and untreated, it may result in complete loss of the newly dissected skin flaps. Smaller or delayed hematomas can be managed with serial needle aspiration and pressure dressing. These complications are minimized with careful attention to intraoperative hemostasis. Use of closed suction drains may be helpful.

The most commonly injured nerve in rhytidectomy is the greater auricular nerve. The skin flap in the area of the sternocleidomastoid muscle is adherent to the fascia in which the greater auricular nerve travels. Therefore, sharp dissection or traction can injure the nerve. Attention to detail when dissecting in this area can minimize this complication. The frontal branch of the temporal-zygomatic division of the facial nerve is the next most commonly injured nerve (2.6-4%). It is vulnerable because of its superficial location as it traverses the midportion of the zygomatic arch. A more superficial dissection in this area minimizes neural damage. Injury to the marginal nerve can occur when extensive tissue dissection is performed in the neck. If a platysmal transection is performed, the possibility of nerve injury increases. Buccal motor nerve branches can also be injured with aggressive dissection medial to the anterior border of the parotid gland.

Unattractive wide scars can result from excessive skin tension. This is avoided by careful incision placement, SMAS suspension, and redraping of the skin flap without tension. An elongated earlobe directly attached to the facial skin, known as a pixie-ear deformity, is another common complication. This is prevented by leaving a generous amount of perilobular skin on the redraped skin flap during closure.

Future and Controversies

See Rhytidectomy, Deep Plane Facelift.