Short Notes in Plastic Surgery

November 25, 2014

50. The Aging of the Face and the Neck (Facelift)

Filed under: Chapter 50 — ravinthatte @ 11:37 am
  1. Facelift is perhaps the most frequently performed aesthetic surgical procedure in the northern parts of the western world. The number of ‘face lifts’ performed in the east and the south dwindle, partly because the skin of people in these parts is endowed with pigment which resists actinic changes in the elastic fibres of the skin and the tissue underneath. In countries in the southern hemispheres such as Australia and New Zealand the incidence of the procedure goes up again because of the nature of the population. The South American continent with a fairly mixed population, is for some reason hugely fascinated with all forms of aesthetic surgery and therefore facelifts are probably more frequently performed there as compared to the Asian continent. The incidence of this procedure is also proportionate to the economic development of the population. Members of the richer societies can indulge in this procedure because they can afford it. A sagging face is a natural consequence of aging and is not a disease like progeria where effects similar to aging occur due to a genetic disorder leading to premature degeneration of elastic tissue all over the body. There is some evidence to suggest that abuse of alcohol and tobacco and almost continuous use of heavy makeup with cosmetic products and a reckless irregular lifestyle (à la Oscar Wilde’s Dorian Gray) all hasten ageing of the face.
  2. The name Facelift suggests lifting the face but this was not what was done at the turn of the last century when the procedure first came to be performed. What was done was to tighten the skin by taking incisions mainly in front of the ear undermining it somewhat and excising what was loose or redundant ! (Fig. 1-2) This resulted in what is commonly described as a wind tunnel or windswept appearance because it was not realized that the layers of the face had sagged or fallen downwards with their own weight. The vector was therefore wrong (horizontal). As a modification the incision was then changed to extend into the temporal region and behind the ear around the lobule to pull the skin upwards and laterally which improved the results because the vector had changed from horizontal to obliquely upwards (Fig. 3-4). Slide1
  3. As the demand for this lucrative procedure increased clinical anatomists have taken great interest in the layers that invest the facial skeleton and are generally in agreement on the following points:

a.  In grown up young adults the subcutaneous fat is evenly distributed over the face except for the malar and sub-mental regions where it forms thicker distinctive pads (Fig. 5). The buccal pad of fat is deeper (Fig. 6), not subcutaneous. This buccal pad of fat, so distinctive in the chubby cheeks of infants reduces considerably by the age of five and then remains stationary in volume till the fifth decade of life when it atrophies and with the rest of the tissues in the face and might be displaced downwards with gravity as its surroundings loosen up. The face is covered by a modified form of superficial fascia also called the superficial musculo-aponeurotic system and it lies deep to the sub-mental and malar pads of fat (Fig. 7) (please see next paragraph).

Slide2

b.  The SMAS is considered crucial to the anatomy of the face by surgeons who practice facelifts and is a modified superficial fascia which invests the frontalis muscle above (please see chapter on Browlift) and the platysma below from just above the mandible to the root of the neck (Fig. 8). The SMAS is penetrated by ligaments which end up attaching themselves to the dermis and arise from the malar eminence and the horizontal ramus of the mandible. The masseteric and parotid fascia also send ligamentous extensions in to the SMAS. In the young adult these ligaments run at right angles to SMAS and therefore suspend the SMAS like prongs in a curtain (Fig. 9a and 9b). The malar and sub-mental pad of fat are closely aligned with SMAS and therefore are also held up indirectly by these ligaments. As age advances in addition to changes within the skin, which loses elasticity, these ligaments also lose their bridle effect and in any surgery to lift the face, the SMAS together with the skin will need correction. This then together with the relocated malar pad of fat and the sub-mental fat is called fascial sculpting rather than a facelift. SMAS as it extends laterally, merges with the mastoid and masseteric fascia, the capsule of the carotid and then above with the temporal fascia. It is less mobile over the parotid, the masseter and the forehead and also along the lateral part of the neck as compared to the anterior part of the face (Fig. 10).

Slide3

c.  Lower down in the neck as the platysma courses down to the clavicle the SMAS has several attachments beginning with the hyoid and then the thyroid cartilage by ligaments (Fig. 11). The cricoid too has similar attachments but are not as prominent as those on the hyoid and the thyroid. In the event when a neck-lift is required and the problem extends throughout the neck only a facial approach is unlikely to suffice (Fig. 12) and a sub-mental incision needs to be taken to fully lift the SMAS as well as the platysma and excise whatever is necessary (Fig. 13). The SMAS which is the investing layer of the platysma is covered with some amount of fat in the neck. It is considered important to suck the fat out in order that the reconstructed SMAS platysma unit will drape over the skin of the neck.

Slide4

d.  Several facial muscles that lie underneath the SMAS are called mimetic muscles because they together contribute to facial expression. Though the muscles in the anterior two thirds of face are mainly identified as giving expression to the face, the frontalis above by raising eyebrows, the platysma in the neck by way of some ticks as well as by stretching it and the masseter laterally by clenching teeth to show resentment all contribute to emotions. The platysma and frontalis have been described earlier. Of the remaining, the buccinator used to show exasperation by blowing one’s cheeks is the deepest and supplied by a branch of the facial which enters it from its superficial surface. The levator anguli oris somewhat superficial to the buccinator is yet deeper than the rest of the mimetic muscles and all of these are supplied by the facial nerve which enters them from the deeper surface. These muscles are covered by a comparatively mobile SMAS which is more adherent to the parotid and the masseteric fascia and is penetrated by ligaments which arise from them. This anatomy is relevant if the surgeon is going to enter the sub-SMAS plane. Advocates of the sub-SMAS facelift believe that it drapes the SMAS better over the mimetic muscles after it is lifted, trimmed and sutured to the adjacent deeper layers. This in their view returns to the face, a more natural expression (Fig. 14).

Slide5

e.  When the skin of the face is viewed with structures beneath it in mind and when the lines of natural tension of the skin are observed, the area in front of the ear is what can be called as a neutral zone and is usually used to incise the skin for the mid-face (Fig. 15). An extension of this incision superiorly can be easily hidden within the hairline. This incision helps to access the lateral orbital and the malar skin. The lower part of the incision skirts around the lobule around 2 mm below and behind it so that the lobule is not displaced and when closure is completed, distortions do not occur. The same incision then goes around the ear over the mastoid process and then can be located in the post-mastoid hairline (Fig. 16). This incision allows access to the lower face, the area around the horizontal ramus of the mandible and the neck in its upper one third up to the thyroid cartilage. The dissection is in the subcutaneous plane which is distinct though traversed by thin ligaments and the plane can be improved by injecting liberal quantities of a weak saline-adrenaline solution. The whole dissection extends upto the lateral parts of the eyelids, the malar pad of fat up to the angle of the mouth, the sub-mental pad of fat and the platysmal layer of the SMAS in the upper-third of the neck. In the raw area thus created around and below the mandible, the great auricular nerve is in the zone of dissection and must be carefully looked for and saved (Fig. 17). Hemostasis is achieved by electro-cautery by lifting and then peeping under the large facial skin flap and a fiber optic light is helpful in this cauterization. The skin is now pulled obliquely and superiorly and because it is separated from its attachment to the SMAS can now be excised in required dimensions and then sutured along the original incisions usually in two layers intra-dermal and cuticular. Because the vector is oblique superio-laterally, the breadth of the skin excised in front of the ear maybe considerably less than in the temporal region (Fig. 18-20). Some form of drain may be kept and is brought out from behind the ear. The face is usually covered with a soft cotton wool dressing. The skin flap is abundantly vascular and the cuticular sutures are never kept for more than 10 days.

Slide6

f.  While this skin lift was the original procedure described for an ageing face, it has now been modified mainly with procedures on the SMAS (please see below) which is considered more effective in picking up the platysmal laxity and lifting up the sub-mental and malar pad of fat. However, at a recent meeting in India a surgeon with considerable experience and seniority from the North American continent stated that he after trying a variety of additional procedures (mainly on the SMAS) had come to the conclusion that a skin lift alone is as satisfactory (or unsatisfactory) to patients (!) as every other procedure. He also noted that the face tends to sag at the same rate over the years post-operatively irrespective of the procedure performed. This statement is experiential (not anecdotal) and needs to be borne in mind. Procedures such as facelifts cannot really be measured for their success either by measurements or by photographs and such experiential statements therefore hold some value.

g.  To improve on the results of a pure skin lift the SMAS is plicated with an unabsorbable continuous stitch in the form of a garland beginning in the lower parotid area going to the level of the angle of the mandible and then below coursing around the upper part of the neck and return towards the mid-face and is then pulled towards the malar eminence, the zygomatic arch and even going up to the temporal fascia and is then tied on itself or the deeper tissues after judging the effects that it creates. This lifts up the malar and sub-mental pad of fat in an indirect manner. This seems to be the most popular current practice (Fig. 21). As a modification the SMAS can be separated from its malar attachment by incising it and can be folded on itself after pulling it up. This accentuates the malar eminence (Fig. 22).

Slide7

h.  In a further modification called SMASectomy, the SMAS is lifted by developing a plane between it and the masseteric and parotid fascia. This needs a sharp dissection because the SMAS is adherent in this area till the dissection reaches upto the mid face where the SMAS is more mobile. A branch of the facial nerve which supplies the levator anguli oris is encountered in this area and the dissection needs to be done carefully. The apron of the released SMAS is then excised in the pre-auricular temporal and mastoid region and after treating it as a flap and sutured to the deep fascia as appears appropriate. Simultaneously in some cases the malar pad of fat can be hitched up from its descended position. The sub-SMAS dissection is difficult because of a poor plane and the danger of injuring the branches of the facial nerve as it emerges from the parotid has meant that the procedure is less commonly performed (Fig. 23).

Slide8

i.  In those cases where the facelift is mainly required in the mid-face and a lower lid blepharoplasty is to be performed simultaneously, the access to the mid-face can be achieved by splitting the orbicularis oculi to access the slackened SMAS in that region which then can be lifted and sutured obliquely in the temporal region. This procedure effectively lifts the malar pad of fat as well and is called trans-bleph mid-face lift (Fig. 24).

Slide9

j.  The normal naso-labial grooves of adulthood tend to become naso-labial folds in some people and can mar the appearance of the face. The dermal ligaments in the groove continue to remain attached to the mimetic muscles below but for some reason fat gets deposited on its lateral side to which the descent of the malar pad of fat also contributes. The standard face lift with or without procedures on the SMAS does not seem to solve the problem because the nasolabial fold is farthest from the incision both in the skin and the SMAS. Therefore the effect of tightening of the skin in the nasolabial fold is minimal. One of the ways in which this problem can be dealt is to hitch the malar pad of fat high up in its original location. However it appears that no agreeable and perfect solution is available in this regard. Fortunately an external naso-labial incision deep up to the level of the muscles followed by meticulous closure deals very effectively with this condition and almost always never gives bad scars because it is in the area of minimal tension in the skin and the scar falls nicely in the area of the original groove (Fig. 25-28).

Slide10

The same principles apply to what is known as a neck-lift. The lax skin and the SMAS in the upper part of the neck can be effectively dealt with a skin, skin and SMAS plication or a sub-SMAS lift (Fig. 29) but a different direct procedure continues to be practiced in which an incision is employed in the sub-mental groove, the skin and SMAS together with platysma is pulled up, the excess is excised and the wound closed meticulously (Fig. 30-31). As mentioned earlier, some liposuction might be employed superficial to the SMAS.

Slide11

k.  The commonest complication following a facelift is post-operative bleeding even though the bed and the under surface of the skin flap were dry at the time of closure. This is called reactionary hemorrhage when blood pressure rises as anaesthesia wanes off and the effect of hypotensive agents used during surgery abate. It is crucial that this complication is detected quickly. Only occasionally the edges of the wound will bleed but otherwise the swelling is obvious and is frequently accompanied by restlessness, pain and nausea. Temporization does not work; the sutures have to be removed, the flap lifted again and meticulous haemostasis has to be achieved. Some of these clots are difficult to dislodge and copious irrigation might be required. If a drain had not been kept at the time of original surgery, some form of drain is now usually put before the skin is closed. The incidence of necrosis of skin is higher in cases where such a complication occurs but otherwise it is not a frequent occurrence. The post-auricular area is the most vulnerable where the skin is extremely thin and the dissection might have damaged dermal circulation. Pharmacological intervention does not help. The flap requires to be observed, debridement is performed only when the necrotic area is well demarcated. It is best that healing is allowed to occur with secondary intention if the area is small. Usually it is not possible to pull the flap any further and should the area be large, a full thickness graft of a proper colour match might have to be performed. The commonest nerve injury in either the skin lift or SMAS plication is to the great auricular nerve which is superficial in the area posterior to the mandible. This nerve requires to be looked for to avoid injury. If it is found that it has been cut, it is best repaired with some form of magnification on the table itself. In either a pure skin lift or together with SMAS plication injury to the facial nerve branches is rare though the stitches that pick up the SMAS might inadvertently produce effects resembling neuropraxia in any of the branches. These recover in a matter of four to six months or even earlier. The injury to the facial nerve in the sub-SMAS operation is more likely. Of these, the nerve to the buccinators (buccal branch) is the most vulnerable to injury because it enters the buccinators from its outer surface and this surface is not protected by any mimetic muscles. The other nerve that can be damaged is the facial, more likely branches of the upper division, leading to paralysis of the frontalis muscle and consequently the inability to raise the forehead skin. This too recovers in a matter of three to six months if the nerve has not been actually cut. Infection is rare in the operation of facelift because the area is highly vascular. If infection does occur, it seems to begin in the neck and is evidenced by redness and swelling. In the event antibiotics might be required to be changed to a higher level.

Parag Telang, aesthetic plastic surgeon from Mumbai adds a note of dissent apropos para 3f. I would like to make the following points/observations about this chapter:

  • I don’t agree with the observation that SMAS elevation does not improve the longevity of the result. it has been documented in multiple studies that elevation of SMAS improves longevity of the result as against skin only facelifts.
  • The main advantage of the Minimal Access Cranial Suspension (MACS-Lift) described by Drs Tonnard and Verpaele are that the advantages of SMAS-Lift are achieved without any actual SMAS dissection. By hitching specific points of the SMAS viz, platysma, malar fat pad and the cheek tissue, it is possible to get a very good overall “lift”. TheMACS-Lift is always combined with microfat injections of the nasolabial creases and tear-trough areas. This gives an overall rejuvenated look. So the problem of the nasolabial grooves not getting addressed by the facelift procedure does not occur. In fact, in my practice, I don’t do any facelift without micro fat grafting of selected areas of the face.
  • The placement of the postauricular part of the incision should remain optional. Patients with minimal neck laxity can have a good result by usingMACS-Lift technique with only the preauricular incision. This is because the platysma is going to be hitched up using a non-absorbable suture.

Slide12

Dr. Milind Wagh, an aesthetic surgeon from Mumbai has sent the following critique:

  • Statistics show that liposuction is the commonest plastic surgical procedure.
  • Extensive, supra-SMAS liposuction is almost always done prior to any “neck lift” operation.
  • Naso-labial excision for nasolabial folds is of only historical value and is rarely done now.

The resulting scar cannot mimic the normal nasolabial groove.

  • As in above, a transverse sub-mental incision is now almost never employed to effect any kind of “neck lift”. Most conditions can be treated with liposuction and pulling the lax skin along with the operation of facelift and suturing the undermined and excised flap in the post-auricular area.
  • A small sub-mental incision might be employed if there is a divarication of the platysma leading to a para-median platysmal bands. The muscles are brought together and sutured in the midline and released transversely some length below the hyoid through the abovementioned small incision thereby creating a diamond shaped defect at the lower end of the platysma. This effectively takes care of the lateral bands.
  • Minor laxity of the neck is dealt with supra-platysmal liposuction. The resulting raw area allows the skin to smoothly drape over to give a good result.
  • That the facelift operation lifts the ptotic submental fat is not correct. This ptosed fat is best treated by liposuction.
  • The plane of dissection under the skin while doing a facelift is not an anatomical plane and requires both sharp and blunt dissection through the subcutaneous fat through which ligaments perpendicular to the axis of dissection pass to attach themselves to the deeper dermis.
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