2/6/95 ------------------------------------------------------------------------------- TITLE: CERVICOFACIAL LIPOSURGERY SOURCE: Dept. of Otolaryngology, UTMB, Grand Rounds DATE: December 6, 1995 RESIDENT PHYSICIAN: Christopher Thompson M.D. FACULTY: Karen Calhoun M.D. FACS SERIES EDITOR: Francis B. Quinn, Jr., M.D. ------------------------------------------------------------------------------- "This material was prepared by resident physicians in partial fulfillment of educational requirements established for the Postgraduate Training Program of the UTMB Department of Otolaryngology/Head and Neck Surgery and was not intended for clinical use in its present form. It was prepared for the purpose of stimulating group discussion in a conference setting. No warranties, either express or implied, are made with respect to its accuracy, completeness, or timeliness. The material does not necessarily reflect the current or past opinions of members of the UTMB faculty and should not be used for purposes of diagnosis or treatment without consulting appropriate literature sources and informed professional opinion." A. DEFINITIONS 1. Liposuction involves the removal of unwanted adipose tissue, usually via a suction cannula 2. Lipoinjection attempts to augment subcutaneous deficiencies with fat cells placed through a needle and syringe B. HISTORY 1. Liposuction and transplantation were both described by 1850, and by 1911 histopathology of transplanted adipose was described 2. Liposuction using a cannula was begun in the early 1900s using a uterine curette, but the technique abruptly fell out of favor when a well-known ballerina required the amputation of her leg after a vascular injury 3. Peer quantified the volume reduction in post-transplanted fat in 1950, reporting that 55% remained after one year 4. Experimentation with sharp curettes continued through the 1960s and 70s until the modern method, using blunt suctioning was introduced by Fournier and Illouz in 1978 5. Lipoinjection applications in the head and neck began with Brunings in 1911 as he attempted to correct nasal deformities secondary to rhinoplasty 6. Facial recontouring using the injection of fat was developed by Bircoll who introduced the technique in 1982 C. ANATOMY AND PHYSIOLOGY 1. The architecture of subcutaneous fat consists of adipocytes organized into lobules by a surrounding network of septae and capillaries. 2. The thickness of the fat determines its blood supply a. fat greater than 1cm thick receives a greater share of its blood through ascending fascial arteries b. fat less than 1cm depends on descending branches of the subdermal plexus c. this anatomy explains the findings of skin dimpling due to fat atrophy after liposuction in thin areas when the cannula is directed upward and the subdermal plexus is disturbed d. application of this knowledge also helps to provide more dramatic results in areas of thick fat by directing the cannula over the fascia to disrupt the important part of the blood supply 3. Cervicofacial fat tends to be more stable in both its volume and distribution than fat stores elsewhere, so that generalized weight loss may actually accentuate these areas a. genetic factors seem to be very prominent in the makeup of subcutaneous cervicofacial fat b. surgical removal of fat in this area has provided good long-term results in those patients who exercise and control dietary intake 4. Retractability of the skin after liposuction strongly influences the outcome a. of all the body sites the neck, is by far the area of reatest retractability b. the meeting point between the facial and cervical areas, the jowls, exhibit similar adaptability 5. Studies regarding cell viability after liposuction harvest reveal that the lobular architecture remains undisturbed through cannulae larger than 16 gauge, and that a greater vacuum pressure enhances viability a. histologic examination of transplanted fat reveals cystic cavities surrounded by relatively normal fat architecture b. larger volumes of injected fat created larger cavities with associated fibrosis c. six to nine months are required for graft stabilization, and 20 - 25% of the graft volume should remain D. INDICATIONS FOR LIPOSURGERY 1. Liposuction to recontour the head and neck region a. the most common application involves the restoration of the chin-neck contour in order to create a cervicomental angle of approximately 100 degrees i. the aesthetically pleasing neck is felt to have a well defined mandibular border, a subhyoid depression, and a slightly prominent thyroid notch ii. the ideal patient for this application is a younger one with fat localized to the area rather than general obesity iii. other important factors are good skin elasticity and a superiorly located hyoid bone b. liposuction of the face has indications when combined with rhytidectomy, particularly in patients with excessive preparotid, nasolabial, and malar fat pads c. loose skin in the jowls can be lastingly improved after suction lipectomy alone, but results are enhanced with concomitant facelift procedures d. many surgeons now use liposuction in the submental, cheek, lateral neck, and nasolabial fold before developing routine rhytidectomy flaps, making them easier to dissect 2. Liposuction techniques have recently been described in the excision of lipomas of the head and neck 3. Recontouring of both free microvascular and locoregional flaps in the head and neck is another recent application of liposuction E. PREOPERATIVE PLANNING FOR LIPOSUCTION 1. Preoperative counseling is important to ensure realistic expectations - the patient must understand that changes may continue 6 - 8 months post-operatively 1. In the sitting position the lower border of the mandible is marked, as is the extension of the jowls below 2. Palpation of the fatty areas allows the creation of a topographical map on the face and neck 3. The medial border of the platysma is then marked if possible F. TECHNIQUE - LIPOSUCTION 1. Anesthesia is accomplished with a combination of local infiltration and intravenous sedation 2. A great variety of cannulae are available, but for facial liposuction the 2 to 6 mm blunt-tipped versions are universally accepted a. cannula size has a significant effect on the post- operative contour of the skin; there is a reduction in surface irregularities by using more passes with the smaller cannula b. the cobra-tipped cannula has greater usefulness in areas of dense, fibrotic tissues, but is more likely to cause neural, vascular, and skin damage c. both metal and plastic cannulae are available 3. The vacuum pumps only requirement is that it generates at least 1 atmosphere of negative pressure 4. The “wet” technique of liposuction has become widespread in liposuction of other body areas a. this involves the infiltration of a hypotonic saline solution containing lidocaine and epinephrine which not only decreases bleeding, but assists in the development of tissue planes and the dislodgement of fat b. in the head and neck, this method loses attractiveness as it distorts the surgical field making determination of contour and volume more difficult 5. Closed techniques describe the use of liposuction without adjunctive procedures such as rhytidectomy a. the ideal incision is small and slightly distant from the localized area of excess fat, and is placed in an inconspicuous site such as the submental area or just inferior to the ear lobe b. the entrance for the cannula is created with blunt tipped scissors, which is then oriented along the plane of dissection c. by rolling the fat with the other hand, the tissues are stabilized as the cannula is used d. dry, pre-tunneling with gradually enlarging cannulae is felt by some to help dissection and prepare the wound for the passage of the larger cannulae; others advocate beginning with the desired size with suction e. once the appropriate size is reached, the dissection is performed with suction in a radial fashion as each tunnel is created with 10 to 12 passages of the cannula f. lateral dissection with the cannula is not advised as good evidence exists to support the idea that the septae between the tunnels contain neurovascular tissues g. although pictured differently, most surgeons agree it is imperative that the suction port be directed downward at all times to avoid dermal damage and post-operative atrophy leading to dimpling h. in the neck, the plane of dissection is between the dermis and the platysma i. for more dramatic results, some surgeons advocate the removal of subplatysmal fat in the submental region, between the medial borders of the muscles ii. great care must be taken in this instance to avoid the appearance of an unnaturally thin neck i. this technique is similar among the other sites of the head and neck; these figures illustrate approaches to the lateral neck, jowls, cheek, and melolabial regions j. applications in the face must be undertaken with care to avoid dissecting above the Frankfort horizontal, and within 2 cm of the oral commissures; facial nerve injury is common after dissection in these areas k. determination of the correct amount of fat to remove is obviously subjective, but preoperative planning as well as intraoperative palpation give indications as to the appropriate stopping point l. postoperative care consists of a support bandage, usually neoprene, which is worn continuously for the first week followed by 3 weeks at night; in almost all cases, this compressive dressing obviates the need for drains 6. Open liposuction is performed beneath a skin flap under direct vision and is nothing more than a combination of liposuction and rhytidectomy a. various methods of combining the two procedures exist i. Teimourian uses the cannulae to develop the skin flaps, followed by sharp dissection with the scissors to take down the intervening septae; this, he claims, dramatically reduces the time for flap elevation ii. others use the suction cannula to remove fat overlying the SMAS (superficial musculoaponeurotic system) once the flaps are elevated, and perform the submental liposuction through the existing incision 7. Recently, liposuction assisted debulking of pedicled and free flaps have been described 8. Complications for these procedures are essentially those of rhytidectomy a. hematoma b. platysmal banding c. recurrence d. skin dimpling and irregular contourinq e. facial nerve paresis/paralysis G. LIPOINJECTION 1. Much of our knowledge concerning the histology of transplanted fat comes from Peers work in the 1950s a. this work is responsible for cell survival theory which explains that a certain percentage (40-60%) of the transplanted adipocytes survive; older theories describe the process of histiocytic replacement of the fat cells with subsequent fibrosis b. the survival of the graft is dependent on the reanastomosis with the host vasculature rather than neovascularization, although the nonsurviving cells are not necessarily located in the grafts center 2. More modern studies examining transplantation of suctioned fat confirm Peers work and provide guidelines for harvesting and injection a. the use of vacuum suctioning harvest produces viable grafts when the negative pressure is maintained at 0.5 atmospheres or lower; some surgeons however, advocate manual suction techniques b. both harvest and injection should be done through an 18 gauge needle or larger to maintain graft viability 3. Applications of lipoinjection a. for the aging face, six sites for augmentation have been described including the nasolabial folds, oral commissures, mentum, glabellar frown line, inframalar groove, and cheek hollows b. some of the other indications include depressed scars, depressed skin grafts, hemifacial atrophy, facial lipodystrophies, and parotidectomy defects c. other applications exist, but this technique is useful only for subcutaneous ugmentation, and will not benefit areas in which there are dermal irregularities 4. Techniques a. attention to sterile technique throughout the procedure is vital, as infection rates have been quoted to be between 2 and 3%; more recently, toxic shock syndrome was reported following lipoinjection of the face b. choices for donor sites are numerous i. areas of low vascularity such as the trochanteric region, or the upper part of the inner thigh seem to be the most attractive ii. in thin individuals it is sometimes necessary to use the more vascular, periumbilical area c. augmentation of small (<2ml) defects is performed most easily with a syringe and an 18 gauge needle i. incremental deposition of the fat seems to produce better longevitiy in the graft ii. some authors suggest 0.1 ml volumes while others use up to 1.0 ml iii. overcorrection of 20 - 30 % seems to be the most agreed upon range for small defects d. larger defects (2 - 20 ml) will require a small liposuction cannula and a small incision i. limited undermining of the defect may be necessary to achieve an even distribution ii. as in the smaller defects, incremental deposition provides better results iii. resorption seems to be more prominent with larger volumes of transplantation with most authors suggesting overcorrection of 50% e. fat handling - a variety of treatments have been devised to prepare the harvested adipocytes for transplantation i. the simplest and most widely used is a saline wash to remove dead tissue, debris, and blood which theoretically increases the bacteriologic medium ii. others suggest that wrapping the harvested fat in cottonoids acts to concentrate the graft prior to injection iii. more involved techniques include insulin baths designed to decrease lipolysis and increase the glycogen and lipid formation within the cells iv. Eppley used bovine basic fibroblastic growth factor and was able to demonstrate a greater proportion of intact fat cells compared with controls 5. Long-term results a. many surgeons remain skeptical about the long term results of lipotransplantion as a result of several early studies demonstrating poor results due to atrophy b. more recent histological and clinical studies now suggest that with meticulous technique for harvest, transfer, and deposition excellent long term results can be achieved c. in addition to handling of the grafts, overcorrection of the defect is imperative for satisfying post-operative aesthetics i. 20-30% overcorrection for defects 2ml or less ii. 50% overcorrection for larger defects --------------------------------------------------------------------------- BIBILIOGRAPHY 1. Bailey BJ. Head and Neck Surgery - Otolaryngology. Philadelphia: JB Lippincott, 1993. p2309 2. Boyce RG. The use of autogenous fat, fascia, and nonvascularized muscle grafts in the head and neck. Otolaryng. Clinics of North Am. 1994;27(1):39. 3. Goddio AS. Suction lipectomy; the gold triangle of the neck. Aest. Plast. Surg. 1992;16:27. 4. Kamer FM. Submental Surgery. Arch Otolaryngol Head Neck Surg. 1991;117:40. 5. Moreno A. Esthetic contour analysis of the submental cervical region. J Oral Maxxilofac. Surg. 1994;52:704. 6. Niechajev I. Long-term results of fat transplantation: clinical and histologic studies. Plastic and Reconstructive Surgery 1994;94(3):496. 7. Perkins SW. Use of submentoplasty to enhance cervical recontouring in face-lift surgery. Arch Otolaryngol Head Neck Surg 1993;119:179. 8. Rhee CA. Toxic shock syndrome associated with suction assisted lipectomy. Aesth. Plast. Surg. 1994;18:161. 9. Teimourian B. Suction Lipectomy and Body Sculpturing. St Louis: C V Mosby Company, St Louis 1987 p65. 10. Wooden AW. Liposuction-assisted revision and recontouring of free microvascular tissue transfers. Aesthetic Plastic Surgery 1993;17:103. --------------------------------END----------------------------------------