TITLE: RHYTIDECTOMY
SOURCE: Grand Rounds, Dept. Otolaryngology UTMB
DATE: November 6, 1996
RESIDENT PHYSICIAN: Chris Thompson, M.D.
FACULTY PHYSICIAN: Karen H. Calhoun, M.D., FACS
SERIES EDITOR: Francis B. Quinn, Jr., M.D.
In the vicinity of 1920 several German and French surgeons began experimenting with face lifting. Little is known of the techniques of this period, because of the prevailing attitude that vanity was not a proper indication for surgery. Any procedure in the pre-antibiotic era carried greater risk than one would experience today; therefore, surgeons were expected to treat only life threatening ailments. As a result, those who did perform cosmetic procedures maintained a low profile, and did not discuss their work in the literature.
The first face lift utilizing extensive subcutaneous undermining began to emerge in the late 1920's. For the next half-century this technique remained essentially unchanged. The next significant advance arrived in 1974 with Skoog's description of the superficial musculoaponeurotic system (SMAS). Instead of placing the tension on the subcutaneous tissue, the lift is achieved with sutures in this deeper layer of tissue. This technique vastly improved both the short and long term results, and remains the standard, even today.
Developments occurring over the last five to seven years include the addition of liposuction cannulas to facilitate flap elevation, and variations of the SMAS lift using deeper planes of dissection. Hamra's deep-plane face lift entails dissection below the SMAS layer. A subperiosteal level of lifting proposed by Tessier specifically addresses the midface. The past two years have also seen the application of endoscopic techniques to face lifting as surgeons strive for smaller incisions and minimal skin excision.
What becomes evident in the evolution of face lifting is the exponential rise in technical variations over the past decade. For one half century there were no significant improvements to the technique. The incorporation of the SMAS layer in the lifting process was certainly a stride in the evolution, but was followed by fifteen years of stagnant development. The 1990's have seen an explosion in variations, and if the adjunctive technique of CO2 laser rejuvenation is considered, the magnitude of the change is even more impressive. The factors motivating these changes are most likely a combination of social acceptance and technologic advance. With an aging population and an ever increasing preoccupation with physical appearance, the demand for rejuvenation procedures will continue to expand.
The patient that will benefit most from face lifting is one who retains elasticity in the skin for better redraping, and whose underlying anatomy includes distinct bony landmarks and a paucity of subcutaneous fat. This generally implies that the ideal candidate is a thin woman of northern European descent. However, both men and women of all races are happy with results that return them to a more youthful appearance. Additionally, patients outside of this ideal may benefit from adjunctive techniques such as cervicofacial liposuction or laser facial rejuvenation to alter the subcutaneous and cutaneous anatomies.
As in all surgical procedures, it is imperative that the patient have realistic expectations of the outcome, and thoroughly understand the risks associated with the procedure. Cosmetic procedures are notorious for attracting patients who demand results that are not achievable. However, Dr. Berman makes the claim that in his experience, most patients come with realistic expectations. Careful explanation of the limitations of the surgery, along with the potential problems that may develop is the best defense against unrealistic expectations.
The patient must also understand the post operative regimen and be willing to comply. One recent example of mine was a seemingly compliant woman who thoroughly understood the post-operative instructions, but who removed the dressing shortly after returning home and refused to follow-up the next day for examination and drain removal. This underscores the importance of not only educating the patient on the do's and don'ts, but making sure the patient understands that the final outcome of the surgery may depend on these instructions so the patient will take some responsibility.
Analysis of the face prior to lifting includes assessment of the chin and malar prominence, nasolabial folds, jowl area, jaw line, hyoid position, platysmal banding as well as the quality of the skin and the amount of subcutaneous fat. Adjunctive implanting procedures produce excellent results in the correction of underprojected malar prominence and chins, and should be considered in appropriate patients. Hypertrophic nasolabial folds have never responded well to SMAS lifting, but the newer techniques seem to address the problem well. Jowl and jaw line improvements remain significant with the standard SMAS lift, but the deep plane technique has been touted to provide better and longer lasting results. Hyoid position is difficult to alter, but is a good predictor of outcome. A low lying hyoid produces an obtuse and less attractive cervicomental angle and should be discussed with the patient to ensure a reasonable expectation of outcome. Platysmal banding must be addressed with platysmaplasty, and routinely produces good results. Excessive subcutaneous fat should be addressed with liposuction, and skin quality improvements are easily attainable with CO2 laser treatments, at least in the short term. There are many variables in such an analysis, so that a systematic approach, followed by a detailed discussion with the patient, is necessary for preoperative planning.
Preoperative photography includes the standard A-P, oblique, and profile views with close-ups of any pertinent areas. As always, consistency in this process is necessary to allow meaningful analysis post-operatively. Equally important is the photographic record of any asymmetries such as facial nerve weakness, asymmetric smile, asymmetric submandibular gland ptosis, eyelid ptosis, and scars. The latest development in photographic analysis is the digital camera with images that can be manipulated on the computer. This technology allows the patient to see a photographic prediction of the post-operative result. As the price of these systems come down, they will likely become an integral part of the preoperative process.
The preoperative workup also includes a thorough history and physical exam. Alcohol intake and tobacco use have a significant impact on bleeding and postoperative healing. Smokers have been shown to have a twelve fold increase in postoperative skin slough, so the technique must be modified in these patients. Having the patient stop smoking one month prior to and after surgery will significantly limit the perioperative risk. All patients should be instructed to discontinue aspirin, non-steroidals, and steroids at least two weeks before surgery. A history of Bell's palsy should alert the surgeon to an increased risk of palsy postoperatively. The workup in a purely elective procedure such as this must be thorough, because a preventable complication will have much greater significance.
The SMAS is a cervicofacial layer of tissue made up of both fibrous and muscular elements that enmeshes and distributes force among the facial mimetic muscles. In the scalp, the galea is synonymous with the SMAS. As it proceeds inferiorly the SMAS is made up of the superficial temporal fascia or the temporoparietal fascia. At the level of the zygomatic arch, the SMAS is discontinuous and is not used as a surgical plane because of risk to the frontal branch of the facial nerve. Below this level however, the SMAS becomes substantial again, and exists superficial to the parotid fascia. Anteriorly, at this same level, this layer envelopes the zygomaticus major muscle. Because this muscle has cutaneous attachments at the nasolabial crease, traction on the SMAS pulls directly on this crease to actually widen and deepen it. In the neck, the platysma is the SMAS layer with dehiscences at the midline and lateral to the angle of the mandible.
The blood supply to the flaps elevated in facelift surgery come from branches of the external carotid arteries. The majority of the supply exists with the branches of the facial and infraorbital arteries. These are musculocutaneous branches. Because dissection is carried out under the fascial layer, it is important to leave fibrous septa attached to the flap, especially in smokers. This allows preservation of the septocutaneous vasculature without compromising flap mobility.
Knowledge of the nervous anatomy pertinent to facelifting makes for a much safer procedure. Sensory nerves are the most commonly injured, with the greater auricular nerve making up the vast majority. A simple method of approximating this nerve is to find the midpoint between the mastoid tip and the mandibular angle. This is where the nerve will cross the SCM. Unfortunately, the flap elevation in this region requires sharp dissection because of its adherence to the underlying tissues. Unless a subcutaneous plane is followed, it is easy to enter the fascia of the SCM and place the nerve at risk. With newer techniques of midface lifting and subperiosteal dissection, the infraorbital and mental nerves may also be encountered. Again, knowledge of their anatomy will help prevent complications
Surgeons experienced in parotidectomy undoubtedly have an advantage in facelifting with such intimate knowledge of the facial nerve anatomy. Having visualized the facial nerve completely dissected, we can appreciate that the branches most at risk are the marginal and frontal. This is due not only to their vulnerable location, but also because of a lack of anastomoses, that does exist in the central branches. The frontal branch emerges from the parotid to cross the zygoma beneath a dehiscent and unreliable SMAS. Safe dissection here requires a subperiosteal plane. Above the zygoma, the nerve lies deep to the SMAS (superficial temporal fascia) as it courses between the superficial and deep layers of the deep temporal fascia. To avoid injury to the nerve at this level, dissection between the superficial and deep layers of the deep temporal fascia, or in a sub-follicular plane is necessary. This branch then goes on to innervate the frontalis and orbicularis musculature. An interesting point made by Ramirez is that in approximately 10% of the population, the nerve innervates the orbicularis occuli on its superior surface. This makes the nerve extremely vulnerable in the area of the lateral canthus. The zygomatic and buccal branches exit the parotid at its anterior extent to innervate the paranasal and lip musculature. This innervation occurs on their deep surface making the supramuscular plane a safe level. The marginal mandibular branch lies one to two cm below the inferior border of the mandible before it courses anterosuperiorly to innervate the lip depressor musculature. This branch is protected by the platysma until approximately two cm from the oral commissure. Motor nerve damage is a rare, but devastating complication of facelifting. Knowledge of the anatomy, and the exercise of caution when dissecting near the zygoma or within two cm of the oral commissure will help keep such injuries a rarity.
Although several variations to this technique now exist, the SMAS suspension technique remains the mainstay for most facial plastic surgeons. Familiarity with this technique is also a great advantage, if not a necessity, when experimenting with the newer techniques. This method produces reliable, long-term results with a minimum of morbidity, and may be combined with adjunctive liposuction or augmentation of the malar or mental areas.
In the preoperative holding area, landmarks and incision lines are drawn on the patient. With the patient upright, the nasolabial folds, jowl lines, and platysmal bands are marked. We also draw an arc two cm from each oral commissure, a line at the mandibular angle, and a line approximating the frontal branch of the facial nerve. The pre and post-auricular and, if necessary, the submental incision lines are drawn. The patients temporal and post-auricular hair is rubber banded if necessary.
Anesthesia for this procedure may be general, or local with intravenous sedation. We do this procedure almost exclusively under local anesthesia because of the lower cost. However, a great number of surgeons prefer general anesthesia and maintain that the patient experience is better. Regardless of this choice, the incision lines and areas of flap undermining are then infiltrated with a mixture of epinephrine and lidocaine. Because of the volume necessary, it is preferable to use 0.5 or 0.25% lidocaine for flap infiltration to avoid toxicity. The incision lines may be injected with a stronger solution.
The postauricular incision travels horizontally at the vertical midpoint of the ear to enter the scalp. The anterior placement in a man prevents the displacement of hair bearing skin onto the tragus. In the scalp it is important to bevel the incision with the direction of the hair to prevent alopecia. The temporal incision must also be placed carefully, so that the excision of the redundant skin at the end of the case will not drop the incision below the hair-bearing scalp. When combining the lift with a platysmaplasty, a submental incision is created in the submental crease approximately five cm long.
If platysmaplasty is planned, the submental incision is carried to a level just below the dermis. If desired, liposuction is usually performed next using the cannula to dissect a fan-shaped flap. The anterior edges of the platysma are then identified as the flap is elevated with scissor dissection in the subcutaneous plane. With the guideline of the previously marked platysmal bands, the actual bands are identified, cauterized, and incised as low as possible. The anterior edge of each muscle is then approximated with 2-O vicryl. In most cases, skin excision here is not necessary; however, patients with marked excess may benefit from a Z-plasty or elliptical skin excision.
Flap elevation is next begun in the peri-auricular area. As in the neck, a subcutaneous plane is used in all areas except above the zygoma. In this area, a subfollicular plane is necessary to avoid the superficially located frontal branch. Flap elevation behind the ear follows, and will be the most difficult as the subcutaneous tissues are very adherent. Frequent palpation, and visual cues such as a uniform 'marbling' of fat on the flap undersurface will ensure maintenance of a subcutaneous plane. As mentioned, dissection below this plane jeopardizes the greater auricular nerve. Development of about two to three cm of flap here is then followed by elevation in the infra and preauricular areas.
Make sure the infraauricular incision precisely where the neck skin meets the lobule to avoid the pixie ear deformity. Flap elevation continues anteriorly and inferiorly. In patients who smoke or who have diabetes or athrosclerosis, a short flap technique is safest. Three to four cms are elevated anteriorly, and five to seven cms are dissected in the neck. The liposuction cannulas can then be used to tunnel without the use of suction. The tunnels created will allow mobility of the flap without significantly compromising the vascular supply. Adjunctive liposuctioning would also be carried out at this time if the jowls or lateral neck necessitated this. In the nonsmoker, the long flap technique becomes an option. Here the neck dissection is made continuous with that of the platysmaplasty, and the preauricular flap is taken just beyond the anterior parotid edge. In the midface the advantages of the long flap are subtle and do not usually justify the additional risk of limiting the blood supply. In the neck, however, communication between the platysmaplasty and the facelift flaps allows for smoother contour and a greater excision of redundant skin.
With the flaps elevated, the suspension of the SMAS is accomplished with either plication or imbrication. Plication implies sutures that fold the SMAS onto itself to shorten it, where imbrication involves excising a block of SMAS and approximating the cut edges to tighten this layer. Imbrication does not provide any additional benefit according to cadaver studies by Webster, and involves an additional step. Therefore, our method of choice is plication. The placement of sutures and the vectors of tension are well agreed upon. The first suture is applied at the jaw line and is anchored at the mastoid periosteum, or deep tissues in the preauricular area. The choice of suture varies; most surgeons use permanent, while others use a longer lasting absorbable such as vicryl. Several sutures are applied along each vector, and the horizontal mattress technique seems to hold the tissues best. The posterosuperior vector in the neck is then created with sutures in the platysma being tightened by the SCM fascia or mastoid periosteum. Flattening of the jowls is accomplished with the third vector, as the SMAS is pulled with a suture in the deep preauricular tissues.
The SMAS suspension results in a skin excess that will require judicious trimming. The only way to avoid scar widening with healing, is to eliminate any tension on the skin closure. The easiest way of ensuring this is to make pilot cuts in the redundant skin in the same direction that the SMAS was tightened. An anteroinferior incision is made where the lobule will attach. A tacking stitch is applied, and similar pilot cuts are made in front of and behind the ear. The excess skin is then removed by connecting the ends of these cuts.
Closure of the incisions is straightforward, but the decision whether or not to use drains must be made first. No studies have demonstrated a decrease in hematoma formation with the use of drains, but most would agree that a closed suction system will remove intervening fluid and provide better adherence between the skin flap and underlying SMAS. Kridel maintains that patients are more comfortable with the drains because of the lack of fluid build-up beneath the flaps. We use a seven JP drain on each side, and bring it out through a separate stab incision in the postauricular scalp. These are well tolerated and can almost always be removed on the first postoperative day. The skin is then closed with several deep sutures followed by a running 5-O nylon. The hair-bearing skin can be closed with staples. A burrow's triangle is often necessary in the postauricular scalp, and occasionally used in closure of the temporal incision.
For dressing, a nonadherent material is placed over the incisions and gauze fluff is wrapped tightly beneath an ace bandage. The dressing should apply even pressure to the neck and midface skin flaps to promote adherence. After 24 hours, the bandage is removed, the patient is examined, and a commercially available nylon facelift dressing is applied for seven days. Sutures are removed in five days, and staples in seven to ten.
The patient should keep activity to a minimum and maintain head elevation day and night for one week.
Complications in facelifting are most often a result of inadequate hemostasis or overextensive undermining of flaps. The most feared problem is facial nerve injury, but fortunately the incidence is uncommon, between 0.4% and 2.6%. The frontal branch is most commonly injured, and is vulnerable in its superficial path over and above the zygomatic arch. The marginal mandibular branch is at risk with dissection below the platysma at the mandibular angle, and buccal injury accompanies deep dissection medially in the midface. The greater auricular nerve is injured more commonly than the facial and, is vulnerable when the postauricular flap is elevated off the adherent subcutaneous tissues. Such injuries should be repaired primarily if identified at the time of surgery.
The most common complication following facelifting is the hematoma, with some reports placing the incidence as high as 8.5%. The pathophysiology behind this problem is that e the flaps are separated from the deep tissues, limiting the blood supply. Additionally, tension is placed on the flap as the skin expands to accommodate the underlying volume. Skin necrosis routinely follows unrecognized hematomas. Expanding hematomas must be addressed by opening the incisions and obtaining hemostasis. Smaller ones may disappear with serial evacuations. Meticulous hemostasis, judicious flap dissection, and attention to postoperative pain are the best defense against this common complication.
Incisional problems can also ruin an otherwise perfect result, and are usually due to excessive tension. Widening of the scars, hypertrophic scarring, and skin slough can all result from this. Early treatment involves reducing edema, removing sutures causing tension, and, if skin slough occurs, expectant management with debridement and topical antibiotics. Hypertrophic scarring is treated with serial injections of triamcinolone on a monthly basis. Another problem along the incision line is alopecia. Most of the time this is temporary, with a return in about three months. However, approximately 1% of facelifts will be associated with permanent alopecia that may require scar excision or local flap reconstruction. Again, tension is the major culprit along with poorly planned incisions.
This technique evolved from the original SMAS suspension in an effort to better address the nasolabial fold. There is a limitation of the SMAS technique in eliminating the nasolabial fold. Because the flap is not elevated to the nasolabial fold, tension in the SMAS laterally serves to deepen the fold. The deep plane technique which was described by Hamra in 1990 allows elevation of a long enough flap to address this area, without compromising the blood supply. Most surgeons using this technique also claim that the technique will produce better long-term results. Obviously, much time must pass before that statement can even be put to the test.
Kamer recently described his experience with the deep plane technique in 100 consecutive patients in the literature, and has since doubled that number. The results have not differed between the two groups. His technique begins with the same incisions described above, and even involves a similar subcutaneous dissection anteriorly for four to five cms. At a line drawn between the malar eminence and the mandibular angle, a vertical incision is made into the SMAS and dissection proceeds anteriorly. Within one to two cms, the zygomaticus muscle is identified and dissection continues on its superficial surface. The nerve branches enter the muscle deeply, and are therefore out of the way. This dissection is carried from the prezygomatic area to the corner of the mouth (modiolus), and anteriorly to the root of the nose. The dissection along the mandible continues as above, and the fascia overlying the masseter muscle is soon encountered. Kamer describes anterior dissection past the masseter to the point where the facial artery crosses the mandible. He maintains that if the underlying parotidomasseteric fascia is left in tact, no injury to the marginal mandibular nerve is possible. Treatment of the neck is similar to that described above, as is the suspension and closing techniques.
The complication rate in this series was comparable to that of the standard technique. He saw a 2.8% incidence of hematoma formation, and no instances of motor nerve damage. Greater auricular nerve injuries were not mentioned. 10% of patients complained about scarring, and there were no keloids. Overall, he felt that the complication rate and recovery period were similar to the standard technique, and the flap viability and contour improvement in the nasolabial fold and jowl region were better.
This technique grew out of a desire to lift the midface and periorbital area which are not adequately addressed in the standard SMAS or sub-SMAS procedures. Tessier first described this concept in 1979, but the procedure held little appeal with its coincident frontal branch paralysis in 20% of subjects. Multiple modifications have been applied, mainly to the dissection over the zygomatic arch. In capable hands, the technique now represents a minimum of risk to the nerve, and has been particularly prevalent in the literature since the early 90's. With the application of endoscopic technology to this operation, its future looks very promising.
Because of the high incidence of nerve injury in Tessier's technique the dissection was then modified to address only the anterior portion of the zygoma. The likelihood of nerve damage improved, but the tissues remained tethered on the zygoma and produced disappointing results. Ramirez further modified the dissection. Instead of approaching the zygomatic arch beneath the temporoparietal fascia, he travels under the deep temporal fascia, and in his initial series of 34, he had only one transient paresis.
Ramirez's technique involves a coronal incision, and subperiosteal/sub-temporal fascia dissection to within two to three cms of the zygomatic arch. He enters the temporalis fascia at this point and identifies a plane below both the superficial and deep layers of fascia. When the arch is identified, a blade is used to incise the periosteum at the superior border. An elevator is then used to lift the periosteum from the root of the zygoma to the lateral canthal attachment. The fascia of the masseter is then encountered below the arch, and its overlying fascia is lifted. The remainder of the dissection is accomplished via gingivobuccal sulcus incisions. The persisting attachments in the midface are taken down in a subperiosteal plane, taking care to avoid injuring the infraorbital nerve.
Suspension is accomplished by anchoring mattress sutures to the cut edges of the temporalis fascia on the flap, and tying them to approximately two cms above the superior incision in the temporalis fascia. As in a coronal browlift, the appropriate skin excision is accomplished and the skin is closed. Ramirez felt that in his series, the perioral and periorbital tissues were rejuvenated by this pull, areas that the standard lifting techniques could not access. His complications were limited to a single hematoma that resolved spontaneously, and the above mentioned frontal branch paresis. Although 20% of the subjects were smokers, no flap necrosis was seen, likely a result of the flap thickness.
Several years after the above description, Ramirez further modified the anchoring technique, describing the SOOF or suborbicularis occuli fat pad. He also began describing the use of endoscopic techniques with the subperiosteal lift. The name is somewhat misleading because the tenacity required for anchoring this layer is provided by the periosteum underlying this fat pad. As pictured, this fat pad lies beneath the orbicularis occuli, and may act to cushion its movement. The periosteum of the SOOF is attached to this fat pad and seems to be continuous with the levator labii medially, and the zygomaticus laterally. Because of these attachments, lifting this layer tightens the perioral musculature, while elevating and lateralizing this fat pad. Ramirez feels that the displacement of this fat acts as a malar implant to increase fullness in this area. The SOOF is elevated by applying the sutures to the temporalis fascia. This is done in addition to the previously described anchoring sutures.
As endoscopic technology became applied to browlifting, eliminating the need for the extensive coronal incision, subperiosteal facelifting appeared to be a complimentary application. Ramirez took advantage of this, because his modifications of the subperiosteal lift could all be accomplished without the large incisions he had previously been using. As brow lifting has shown us, large areas of skin redundancy at the end of a procedure disappear in the postoperative period. Because midface lifting does not produce a great deal of redundant skin except in the rare patient, most subperiosteal procedures can take advantage of the endoscope. The only difference in the endoscopic procedure is that several small (one to two cm) incisions are made in the temporal and anterior scalp areas. The standard endoscopic brow lift is applied and dissection is carried onto the nose. The zygomatic elevation is accomplished through the temporal incision and carried onto the midface. The SOOF layer is elevated from above, and below through a gingivobuccal sulcus incision.
The suspension in the endoscopic procedure includes the SOOF, and the periosteum near the origination of the zygomaticus muscle. The original temporalis fascia suspension is also applied. The first suspensory stitch is placed into the superolateral margin of the SOOF, and applied to the temporalis fascia. The next one originates in the periosteum near the oral commissure at the origin of the zygomaticus. This suture is also tightened to the temporalis fascia. The placement occurs through the oral cavity incision, and is brought out through the temporal incision. Finally, the standard closure of the temporalis fascia occurs and the skin incisions are closed.
The experience with this technique is limited and only anecdotal reports exist to describe the outcomes. In competent hands, it seems that damage to the facial nerve would be a rare event, and flap viability is certainly not going to be a problem. However, the procedure appears to be technically demanding, and is likely time consuming, at least in the beginning. At this time it, remains to be seen whether or not the rejuvenation is dramatic and long-lasting enough to justify these concerns.
The deep-plane and subperiosteal techniques are exciting new additions to this field, and many surgeons are accumulating experiences with them. Some surgeons report performing them together to address the entire cervicofacial region. What makes these newer procedures even more appealing is the ability to perform them together with laser facial rejuvenation and chemical peels. The SMAS technique is limited by the blood supply to the flaps, with most surgeons agreeing that adjunctive lasering and peeling is not safe. Accomplishing both facelifting and skin treatment at one sitting will be more appealing to the patient, and the early results demonstrate dramatic results. Tightening of the cervicofacial skin, in combination with improving in the quality of the skin really does have a great deal of rejuvenation potential. The next decade will see further modifications and the development of newer techniques, but with their seemingly greater risk of nerve injury and the increased technical demands, many facial plastic surgeons will continue to use the SMAS suspension procedure.
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