Ebook Ballenger’s otorhinolaryngology head and neck surgery (17/E): Part 1

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Ballenger_FM.qxd 8/11/08 9:58 AM Page i Ballenger’s OTORHINOLARYNGOLOGY17 HEAD AND NECK SURGERY Ballenger_FM.qxd 8/11/08 9:58 AM Page ii Ballenger_FM.qxd 8/11/08 9:58 AM Page iii Ballenger’s OTORHINOLARYNGOLOGY17 HEAD AND NECK SURGERY JAMES B SNOW JR., MD, FACS Professor Emeritus Department of Otorhinolaryngology Head and Neck Surgery University of Pennsylvania Philadelphia, Pennsylvania Former Director, National Institute on Deafness and Other Communication Disorders National Institutes of Health P ASHLEY WACKYM, MD, FACS, FAAP John C Koss Professor and Chairman Department of Otolaryngology and Communication Sciences Medical College of Wisconsin Milwaukee, Wisconsin 2009 BC Decker Inc PEOPLE’S MEDICAL PUBLISHING HOUSE SHELTON, CONNECTICUT Ballenger_FM.qxd 8/11/08 9:58 AM Page iv People’s Medical Publishing House Enterprise Drive, Suite 509 Shelton, CT 06484 Tel: 203-402-0646 Fax: 203-402-0854 E-mail: info@pmph-usa.com © 2009 BC Decker Inc All rights reserved Without limiting the rights under copyright reserved above, no part of this publication may be reproduced, stored in or introduced into a retrieval system, or transmitted, in any form or by any means (electronic, mechanical, photocopying, recording, or otherwise), without the prior written permission of the publisher 08 09 10 11 12 / AOP / ISBN 978-1-55009-337-7 Printed in India by Ajanta Offset and Packagings Limited Managing Editor: Patricia Bindner; Cover Design: Elizabeth Hayden Sales and Distribution United States BC Decker Inc P.O Box 785 Lewiston, NY 14092-0785 Tel: 905-522-7017; 800-568-7281 Fax: 905-522-7839; 888-311-4987 E-mail: info@bcdecker.com www.bcdecker.com UK, Europe, Middle East McGraw-Hill Education Shoppenhangers Road Maidenhead Berkshire, England SL6 2QL Tel: 44-0-1628-502500 Fax: 44-0-1628-635895 www.mcgraw-hill.co.uk Brazil Tecmedd Importadora E Distribuidora De Livros Ltda Avenida Maurílio Biagi, 2850 City Ribeirão, Ribeirão Preto – SP – Brasil CEP: 14021-000 Tel: 0800 992236 Fax: 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Tel: 03 5479 7251 Fax: 03 5479 7307 Customer Service New Zealand Phone (Free Phone): +64 (0) 800 449 312 Fax (Free Phone): +64 (0) 800 449 318 Email: cservice@mcgraw-hill.co.nz Notice: The authors and publisher have made every effort to ensure that the patient care recommended herein, including choice of drugs and drug dosages, is in accord with the accepted standard and practice at the time of publication However, since research and regulation constantly change clinical standards, the reader is urged to check the product information sheet included in the package of each drug, which includes recommended doses, warnings, and contraindications This is particularly important with new or infrequently used drugs Any treatment regimen, particularly one involving medication, involves inherent risk that must be weighed on a case-by-case basis against the benefits anticipated The reader is cautioned that the purpose of this book is to inform and enlighten; the information contained herein is not intended as, and should not be employed as, a substitute for individual diagnosis and treatment Ballenger_FM.qxd 8/11/08 ▼ 9:58 AM Page v SECTIONAL EDITORS OTOLOGY AND NEUROTOLOGY LARYNGOLOGY AND BRONCHOESOPHAGOLOGY P Ashley Wackym, MD, FACS, FAAP John C Koss Professor and Chairman Department of Otolaryngology and Communication Sciences Medical College of Wisconsin Milwaukee, Wisconsin Gayle E Woodson, MD Professor and Chief Division of Otolaryngology–Head and Neck Surgery Department of Surgery Southern Illinois University Springfield, Illinois RHINOLOGY HEAD AND NECK SURGERY Andrew P Lane, MD Associate Professor and Chief Division of Rhinology and Sinus Surgery Department of Otolaryngology–Head and Neck Surgery Johns Hopkins University School of Medicine Baltimore, Maryland Scott E Strome, MD, FACS Professor and Chair Department of Otolaryngology–Head and Neck Surgery University of Maryland Medical Center Baltimore, Maryland FACIAL PLASTIC AND RECONSTRUCTIVE SURGERY John S Rhee, MD, MPH Associate Professor and Chief Division of Facial Plastic and Reconstructive Surgery Department of Otolaryngology and Communication Sciences Medical College of Wisconsin Milwaukee, Wisconsin PEDIATRIC OTORHINOLARYNGOLOGY J Christopher Post, MD, PhD, FACS Professor of Otolaryngology, Microbiology and Immunology Drexel University College of Medicine President and Scientific Director Center for Genomic Sciences Allegheny-Singer Research Institute Pittsburgh, Pennsylvania v Ballenger_FM.qxd 8/11/08 9:58 AM Page vi Ballenger_FM.qxd 8/11/08 ▼ 9:58 AM Page vii PREFACE It has been a great pleasure to be associated with John Jacob Ballenger in the production of several recent editions of this book and to work with Phillip Ashley Wackym in the development and execution of this centennial edition of Ballenger’s Otorhinolaryngology Head and Neck Surgery The central focus of the 17th Edition is the important role molecular medicine is playing in understanding the pathogenesis of disease and patient diagnosis and therapy in the first decade of the 21st century The selection of the sectional editors and the senior authors for each chapter was based on their contribution of new knowledge to the subject matter of their sections and chapters through highly regarded research and their intellectual leadership of the specialty, thereby assuring that their contributions to this book are truly authoritative The editorial aim was to encompass the important information in all of the specialties relating to disorders of hearing, balance, smell, taste, voice, speech and language that are the principal responsibilities of the 21st century otorhinolaryngologist head and neck surgeon and to organize and edit it into a comprehensive compendium with an absolute minimum of redundancy In the last ten years, there has been a great deal of international cooperation in understanding and categorization of major disease entities and developing consensus on patient management based on these concepts; the fruits of these labors are to be found in the various sections of the book The book is designed to satisfy the informational needs of developing specialists and specialists wanting to maintain their competence with a reader friendly source of contemporary knowledge The extraordinary currency of this work is largely due to the short time between composition and printing which is a tribute to the publisher, Brian C Decker, and his gifted staff My gratitude goes foremost to Ashley Wackym for his leadership, creativity, brilliant intellect and just plain hard work but in full measure to the sectional editors, authors and illustrators who have made this centennial edition one that will give the reader information, pleasure and inspiration James B Snow, Jr., M.D July 2008 vii Ballenger_FM.qxd 8/11/08 9:58 AM Page viii Ballenger_FM.qxd 8/11/08 ▼ 9:58 AM Page ix FOREWORD One hundred years ago William Lincoln Ballenger at the University of Illinois College of Physicians and Surgeons wrote the great American classic, Diseases of the Nose, Throat and Ear The 17th Edition embraces a tradition, which embodies clear and concise writing with complementary full color illustrative material As the original author expressed in his Preface for the First Edition, the current editors have endeavored to include material that one would find in a “textbook and an atlas.” The editors have expanded this edition into 101 chapters, which offer a comprehensive compilation of the specialty of otorhinolaryngology head and neck surgery The editors chose authors who are experts in their respective fields who have offered reliable and authoritative treatises of their subjects Care was taken to present the scientific underpinnings of each discipline, which provide the basis for diagnosis and treatment The authors have endeavored to include the evidence that underlies management of the disorders The addition of color plates throughout the chapters has added an important new dimension to this book distinguishing it in the field The use of color not only conveys additional information rarely seen in a text of this magnitude but also enhances the appearance of the book The illustration of surgical concepts and procedures in color carries on Ballenger’s original idea of adding an “atlas” to the text The six sections of this book cover the field of Otorhinolaryngology Head and Neck Surgery with thoroughness that includes not only the breadth of the specialty but the depth of knowledge in each of the disciplines As it has for the last 100 years, this book provides a valuable foundation for the library of all otorhinolaryngologists head and neck surgeons Richard A Chole, M.D., Ph.D July 2008 ix 744 PART III / Facial Plastic and Reconstructive Surgery Figure Ideal eyebrow position and proportion The medial aspect of the brow begins at a point tangent to a vertical line drawn through the medial canthus and lateral nasal ala margin and terminates laterally at a point tangent to an oblique line drawn from the lateral nasal ala to the lateral canthus The apex of the brow arch should lie between the lateral limbus of the cornea and the lateral canthus Brow ptosis exists when the distance from the midpupil to the top of the brow is less than 2.5 cm (Reproduced with permission from reference 2.) forehead contour, forehead rhytides and furrows caused by the actions of the underlying musculature should all be considered in the preoperative assessment There are several surgical approaches, endoscopic, coronal, trichophytic, direct, and mid forehead The latter two choices are less commonly used and more appropriate for facial paralysis patients or in men with thick and heavy skin with prominent forehead rhytides The ideal candidate for the endoscopic approach has the following characteristics: female, low hairline, abundant hair, flat contour of the forehead, normal or thin skin, and moderate brow ptosis Patients requiring extensive bone recontouring may be better treated with an open procedure Patients with thick, heavy sebaceous skin and severe brow ptosis are less favorable candidates and may be better served with conventional open skin excision techniques (coronal or trichophytic approaches) Also, surgical weakening of the brow depressor muscles is often technically easier using the open approaches Finally, patients with high hairlines, sparse hair, male pattern baldness, and rounded foreheads are less ideal candidates for the endoscopic approach Regardless of the choice of incisions or approaches, there are basically four steps in executing the brow lift: (1) placement of precise incisions, (2) dissection and adequate release of the scalp and forehead, (3) myotomy of the desired facial expressive muscles, and (4) elevation and fixation of the forehead to the desired level The endoscopic forehead lift has been described using four, five, or six incisions placed to cm behind the hairline (Figure 7) The central incision marks the midline and is the main endoscopic port The two paramedian incisions are placed at the level of the lateral limbus or canthus The two temporal incisions are needed for dissection over the temporalis fossa and allow better positioning the lateral portion of the brow For the coronal brow lift approach, the skin excision is fusiform and placed to cm behind BDBK005-CH60.indd 744 Figure Placement of the incisions for the endoscopic brow lift The paramedian incisions should be tangent to the lateral limbus of the cornea The temporal incisions should be tangent to a line between the lateral limbus of the cornea and the lateral alar base The temporal incisions may be placed made more laterally, depending on individual esthetic desires and goals (Reproduced with permission from reference 2.) the anterior aspect of the hairline A curvilinear incision is drawn to parallel the hairline with the blade beveled parallel to the natural axis of the hair follicles The amount of skin excised is determined preoperatively, generally about to cm The main disadvantages of this approach include undesirable elevation of the hairline, potential alopecia and more visible scars, and paresthesia behind the scalp incision Usually the paresthesia resolves over time, but it can be bothersome to patients during the recovery Candidates who have a high hairline may be best served with a trichophytic approach The incision is made in the gradual transition zone between the thick hair of the scalp and the thin wispy hair at the true hairline The incision parallels the natural curvature of the hairline, and the excision pattern resembles a gentle W-plasty The lateral extensions proceed into the temporal hair about to cm bilaterally The bevel of the blade is usually 60º to 90º to the natural axis of the hair follicle along the hairline and then becomes parallel to the natural hair follicle in the temple The goal is allow the hair follicles along the anterior hairline to grow through the incision to help camouflage the scar As in the coronal approach, usually about to cm of scalp is excised Meticulous closure of the anterior hairline is essential for a successful cosmetic outcome The main disadvantages of this approach are potentially a more visible incision compared to the endoscopic approach and paresthesia behind the incision line In all browlifts, regardless of the surgical approach, the plane of dissection over the skull can be either subperiosteal or subgaleal The temporal incision is extended down to the superficial layer of the deep temporalis fascia Using a freer elevator, the dissection is continued along this plane and the temporal dissection is connected to the subperiosteal plane of the forehead by sharply dissecting the transition zone at the temporal crest line The temporal dissection is continued to the level of the zygomatic arch and the zygomaticofrontal suture line If the dissection is in the correct plane, the temporal fat pad in the elevated flap should become visible as one nears the zygomatic arch A branch of the zygomaticotemporal communicating vein (“sentinel vein”) is often encountered when dissecting near the zygomaticofrontal suture line The vein can either by cauterized with a bipolar cautery or gently dissected from the surrounding tissue The temporal branch of the facial nerve runs in close proximity to the vein Bleeding caused by injury to this vein can lead to poor visualization, and possibly inadvertent injury to the facial nerve from cauterization or further dissection Overzealous upward retraction in the temporal area should be avoided as it may cause traction neuropraxia of the frontal branch of the facial nerve It is important to release fully the entire length of the superior arcus marginalis to achieve adequate brow elevation The periosteum and galea are horizontally scored at this point, exposing the corrugator muscle, procerus muscle, supraorbital nerve, and supratrochlear nerve In patients in whom glabellar muscle modification is desired, the supratrochlear and supraorbital nerves are dissected from the corrugator muscles by using a gentle vertical spreading motion with Takahashi forceps Once the nerves are safely separated from the corrugator muscle, the muscle is gently avulsed or transected The procerus muscle can be approached in similar fashion The subcutaneous fat will become visible upon removal of the muscle Care should be taken not to remove any subcutaneous tissue, as dimpling or contour irregularities will occur It is not necessary to remove all of the muscle fibers to achieve the desired result; the extent of the resection should be tailored to the preoperative assessment of the severity of the glabellar frown lines Surgeons differ in their use of fixation methods to reposition the forehead soft tissues Central brow fixation techniques include the use of miniplates, screws, bone bars, bioabsorbable fixation devices (ENDOTINE Forehead device, Coapt Systems, Inc., Palo Alto, CA), and various suture techniques13–16 (Figure 8) The temporal fixation determines the final position of the lateral brow In the endoscopic approach, the anterior corner of 8/19/08 5:29:50 AM CHAPTER 60 / Rejuvenation of the Upper Face and Midface 745 (A) (B) Figure (A) Preoperative view This patient underwent an endoscopic browlift with the ENDOTINE Forehead device used for fixation, upper blepharoplasty and chemical peel of the lower lid skin (B) Six-week postoperative result Figure Fixation techniques Top row: Variation on the external screw technique A screw is placed at the posterior extent of the vertical incision and the scalp complex is advanced posteriorly Surgical staples are placed behind the protruding screw Bottom row: Creation of an outer cortex bone bar with a cutting burr Suture from the galeal-periosteal layer is secured to the bone bar (Reproduced with permission from reference 2.) the incision is engaged and secured to the desired point on the temporalis fascia, determined by the desired vector pull Regardless of the method of fixation, adequate dissection and mobilization of the forehead tissue are paramount for successful brow elevation In the skin excision techniques, deeper fixation is not necessary; but, as mentioned above, complete release and mobilization of the brow and forehead are necessary for a successful outcome Blepharoplasty Upper Blepharoplasty Surgery of the upper eyelids involves excision of an ellipse of skin, just superior to the tarsal crease The lower limb of the incision is placed in the natural upper lid crease In cases in which the natural crease is not well demarcated, then the lower incision is made 10 to 11 mm above the lash line in women and to 10 mm above the lash line in men The incision extends from the level of the punctum medially to a natural crow’s feet crease laterally at the level of the lateral orbital rim The shape of the excised skin is generally elliptical, with the incision tapered gently medially and wider BDBK005-CH60.indd 745 laterally to address lateral hooding The incisions must be drawn symmetrically or in such a way to account for preoperative asymmetry If a browlift is to be performed, it is performed first to prevent excessive removal of upper eyelid skin during blepharoplasty Once the skin and subcutaneous skin is removed, the orbicularis muscle is divided which reveals the fine connective tissue of the orbital septum This area is carefully separated to expose the medial and central fat pads In some cases, a strip of obicularis muscle can be removed paralleling the skin incision to accentuate the creation of the upper lid crease or to remove hypertrophic muscle The orbital septum is opened to expose the two fat pads of the upper eyelid The fat is conservatively removed from the medial and middle compartments, and hemostasis is meticulously obtained The skin edges are then reapproximated (Figure 9) Lower Blepharoplasty Surgical approaches used to remove prolapsed fat from the lower eyelids can be performed through subciliary or transconjunctival incisions The subciliary approach is generally selected when excess lower lid skin must be excised The plane of dissection is usually under the orbicularis muscle When this approach is used, care must be taken to assess the laxity of the lower lid By using a “snap” or “pinch” test, the resiliency of the lower lid can be ascertained When a lower lid is pulled down and slowly returns to its original position or is pinched and slowly returns to touching the globe, a tarsal suspension procedure must be performed to prevent postoperative ectropion The transconjunctival approach to the lower lids was developed mainly to prevent ectropion After performing the lower lid incision, the three orbital fat compartments (medial, central, lateral) are exposed Each fat pad is dissected free, cauterized, and excised Because the fat pads retract after manipulation, meticulous hemostasis is necessary to prevent an orbital hematoma Increased pressure in the globe from a hematoma can cause a decrease in retinal artery flow and potentially result in blindness Because modern techniques of facial rejuvenation focus on volume restoration, often fat preservation rather than removal is performed on the lower lids, especially in the presence of a tear trough deformity (Figure 10) This area can be approached by either a subciliary or transconjunctival incision Once the three fat 8/19/08 5:29:51 AM 746 PART III / Facial Plastic and Reconstructive Surgery pads are isolated, conservative removal of fat from the lateral compartment is performed Fat from the central pocket may be removed conservatively, if required The white band of the arcus marginalis is identified on the bony infraorbital rim and divided, exposing the anterior maxilla The subperiosteal plane is dissected to allow insertion of the freed fat pad Dissection can instead be performed in the supraperiosteal plane, but dissection through the orbicularis muscle makes this a bloodier plane The fat pad is dissected to allow sufficient rotation and the pedicle thinned to a width of 0.5 to 1.0 cm The pedicled fat pad is actually a random flap, despite the presence of somewhat large feeding vessels Suture stabilization of the fat pad can be performed by suturing to the SOOF or by imbrication Once the fat is positioned, a forced duction test of the globe is performed to ensure no restriction of extraocular movement with upward gaze Patients may experience prolonged edema from subperiosteal dissection The fat pedicle may become hardened for to months postoperatively Long-term fat survival rate may vary, but most patients maintain improvement in the nasojugal region This approach specifically targets the tear trough deformity and does not elevate the SOOF or malar pad (A) orbital septum An incision is created along the arcus marginalis, and the subperiosteal dissection is performed along the anterior aspect of the maxilla The dissection extends laterally to the zygomatic arch and medially to the nasolabial fold, with care to protect the infraorbital nerve The orbital septum is opened and the infraorbital fat from the medial and/or central compartments is draped over the inferior orbital rim, softening the nasojugal groove Through a temporal hairline incision, the superficial layer of deep temporal fascia is isolated for suture suspension of the malar soft tissue complex in the vertical direction Alternatively, an absorbable Endotine implant may be placed on the inferior orbital rim by screw fixation and used to suspend the malar complex A canthoplasty or canthopexy is usually performed to prevent postoperative ectropion Conservative eyelid skin removal may be performed The skin blood supply is not compromised because of the deep plane of dissection, and laser resurfacing or chemical peels can be performed at the same time.17 Figure 10 (A) Preoperative view This patient underwent upper and lower blepharoplasty with lower lid fat preservation and transposition to improve the tear trough deformity, and endoscopic browlift with ENDOTINE Forehead Device fixation (B) Six-week postoperative view Transblepharoplasty Midface Suspension With the transblepharoplasty midface suspension, an extended subciliary approach allows elevation of the malar complex at the same time as softening of the nasojugal groove The subciliary incision is extended 1.5 cm lateral to the lateral canthus A skin-muscle flap is elevated in the plane between the orbicularis muscle and Endoscopic Midface Suspension Since the introduction of endoscopic sinus techniques, the endoscope is used to perform browlifts and midface elevations Multiple techniques for midface elevation exist, most have in common the approach and differ mainly in how the midface is suspended These techniques provide significant elevation of the ptotic malar complex and can be easily combined with an endoscopic browlift Release of the midface tissues is accomplished by creating either a lower blepharoplasty incision or a gingival-buccal sulcus incision and a temporal incision Through the intraoral or blepharoplasty incisions, soft tissue is freed from its attachments to the anterior maxilla via extensive (A) (B) (C) Midface (B) Figure 11 (A) Endotine Midface ST resorbable implant is used to suspend the soft tissues of the midface (B) The five prongs atraumatically grip the soft tissue (C) The ENDOTINE B implant can be used to suspend the malar soft tissues in the vertical direction The superior aspect of the implant is secured to the inferior orbital rim by screw fixation BDBK005-CH60.indd 746 8/19/08 5:29:53 AM CHAPTER 60 / Rejuvenation of the Upper Face and Midface 747 subperiosteal dissection Care is taken to preserve the infraorbital nerve as it exits from its foramen along the inferior orbital rim The temporal incision is carried down to the superficial layer of the deep temporal fascia This dissection is carried inferiorly to the zygomatic arch, where the two pockets are joined over the zygomatic arch (see Figure 2) The endoscope may be used during the temporal dissection, or a lighted Aufrecht retractor may also be used The temporal dissection follows the temporalis fascia to the zygomatic arch The sentinel vein in identified and dissection proceeds lateral to the vein Once the temporal and malar dissections have been connected over the zygomatic arch, the tissue must be suspended Many techniques for suspension exist Sutures can be placed in the malar mound, passed through the tunnel, and sutured to the temporalis fascia This technique is difficult to perform because the sutures can cause puckering of the cheek skin, and it is difficult to obtain symmetry In the past, endoscopic suspension techniques were technically difficult and often required special instrumentation For these reasons, we prefer to use the ENDOTINE Midface ST implant for midface suspension (Figure 11) This implant, a copolymer made of 82/18 L-lactide/ glycolide, is biodegradable months after placement The implant is placed in the midface through the tunnel created over the zygomatic arch The five prongs are used to grasp the malar soft tissue, and the extension or “leash” is pulled superiolaterally and sutured to the temporalis fascia This maneuver elevates the malar complex and slightly flattens the nasolabial fold (Figure 12) The implant is resorbed in approximately months, after the tissue has become adherent to the maxilla (A) (B) (C) (D) COMPLICATIONS Brow and Forehead Lift The incidence of complications for this procedure is quite low Hypesthesia over the forehead and scalp due to traction neuropraxia of the sensory nerves is usually temporary and returns to normal in to 10 weeks There have been some anecdotal reports of temporary weakness of the frontal branch of the facial nerve following the procedure Permanent facial nerve paralysis has not been reported to date Imprecise surgical technique may result in asymmetrical brows, excessive brow elevation or, more commonly, recurrence of brow ptosis Sufficient release of the brow at the level of the orbital rim and adequate fixation will prevent the recurrence of brow ptosis There may be some temporary local alopecia at the incision sites, and bunching of the skin usually resolves in months Blepharoplasty Asymmetry of the upper eyelid tarsal creases is a risk of upper blepharoplasty Failure to recognize a lid ptosis preoperatively can result in an BDBK005-CH60.indd 747 Figure 12 (A and B) Preoperative views This patient underwent a rhytidectomy and midface lift using the ENDOTINE Midface ST implant (C and D) Six-month postoperative photograph shows elevation of the malar tissue asymmetric result Lagophthalmos, the inability to close the lid, can result from excessive upper lid skin excision For that reason, the young surgeon is cautioned to remove conservative amounts of skin during upper lid blepharoplasty If necessary, redundant skin may be removed after the patient has healed, but it is difficult to replace skin postoperatively if the lid is too short A retained fat pad is a common cause of revision surgery of the lower eyelids Occasionally a fat pad is inadequately excised, and a noticeable prominence is present especially on upward gaze These can usually be removed easily by the transconjunctival approach Serious complications of blepharoplasty include injury to the ocular muscles and hematoma Unlike the upper lid, the lower 8/19/08 5:29:56 AM 748 PART III / Facial Plastic and Reconstructive Surgery lid fat is associated with the globe A hematoma of the upper lid is not as serious a problem as it is in the lower lid Meticulous hemostasis is imperative in lower lid blepharoplasty to avoid retro-orbital hematomas Hematomas of the globe can increase intraocular pressure and diminish bloodflow through the retinal artery, ultimately resulting in blindness In addition, extraocular muscles can be injured during lower blepharoplasty Midface The most common complication of midface surgery is asymmetry There not appear to be any significant complications from the fixation devices themselves Care must be taken intraoperatively to ensure symmetric elevation of the malar complex The infraorbital and frontal nerves must be protected from traction injury prolapsed fat, remove excess skin, and reposition ptotic soft tissues No one operation is right for every patient Once the patient identifies the areas of concern, the surgeon may recommend several procedures which can be used to correct such areas Minimally invasive procedures, like botulinium toxin and dermal filler injections, can be used for early signs of aging Once the patient has lost tissue elasticity and support, rejuvenation of the upper face and midface may be necessary Surgical techniques have progressed significantly in these areas in the past 15 years Tissue preservation rather than complete removal is being practiced We can predict that in the future even less invasive techniques will be developed with minimal morbidities and more rapid recovery times REFERENCES CONCLUSIONS Aging of the upper face and midface is secondary to a variety of causes: the effects of gravity pulling the soft tissues inferiorly, loss of skin elasticity due to aging, sun exposure and smoking, and loss of volume of the facial soft tissues Many surgical techniques are available to remove BDBK005-CH60.indd 748 Hester TR, Codner MA, McCord CD, Nahai F Transorbital lower-lid midface rejuvenation Op Tech Plast Reconstr Surg 1998;5:163–85 Rhee JS, Gallo JF, Costantino PD Endoscopic facial rejuvenation In: Wackym PA, Rice DH, Schaefer SD, editors Minimally Invasive Surgery of the Head, Neck, and Cranial Base Philadelphia: Lippincott Williams & Wilkins; 2002 p 355–66 Larrabee W, Makielski K, Sykes J Surgical anatomy for endoscopic facial surgery In: Keller GS, editor 10 11 12 13 14 15 16 17 Endoscopic Facial Plastic Surgery St Louis: Mosby; 1997 p 3–33 Most SP, Mobley SR, Larrabee WF Anatomy of the eyelids Facial Plast Surg Clin N Am 2005;13:487–92 Aiache AE, Ramirez OH The suborbicularis oculi fat pads: An anatomic and clinical study Plast Reconstr Surg 1995; 95:37–42 Freeman MS Transconjunctival sub-orbicularis oculi fat (SOOF) pad lift blepharoplasty Arch Facial Plast Surg 2000;2:16–21 Sullivan MJ Brow and forehead aesthetics Facial Plast Surg Clin North Am 1997;5:95–8 Cook TA, Brownrigg AJ, Wang TD, et al The versatile midforehead browlift Arch Otolaryngol Head Neck Surg 1989;115:163–8 Sullivan MJ Endoscopic facial surgery In: Cheney ML, editor Facial Surgery: Plastic and Reconstructive Baltimore: Williams & Wilkins; 1997 p 913–26 McKinney P, Mossie RD, Zubowsi ML Criteria for the forehead lift Aesthetic Plast Surg 1991;15:141–7 Farkas LG, Kolar JC Anthropometrics and art in the aesthetics of women’s faces Clin Past Surg 1987;14:559–616 Hamra ST Composite rhytidectomy Plast Reconstr Surg 1992;90:1–13 Graham HD Methods of soft-tissue fixation in endoscopic surgery Facial Plast Surg Clin North Am 1997;5:145–54 Bostwick J, Eaves F, Nahai F Forehead lift and glabellar frown lines In: Bostwick J, editor Endoscopic Plastic Surgery of the Head and Neck St Louis: Quality Medical Publishing; 1995 p 166–230 Berkowitz RL, Jacobs DI, Gorman PJ Brow fixation with the Endotine Forehead device in endoscopic brow lift Plast Reconstr Surg 2005;116:1761–7 Guyuron B, Kopal C, Michelow BJ Stability after endoscopic forehead surgery using single-point fascia fixation Plast Reconstr Surg 2005;116:1988–94 Patel BCK Midface rejuvenation Facial Plast Surg 1999; 15:231–42 8/19/08 5:30:00 AM 61 Rejuvenation of the Lower Face and Neck Craig S Murakami, MD Bryan T Ambro, MD, MS Despite the ever-evolving standards of beauty, several classic characteristics of facial beauty have undoubtedly stood the test of time The full, ovoid face highlighted by taut skin, high cheek bones, and an angular neck line remains the esthetic ideal for the youthful face and neck Aging of the lower face and neck is complex and varies from one individual to the next Generally speaking, cervicofacial aging can be characterized by four changes: (1) ptosis of fat and soft tissue, (2) volumetric loss of facial adipose, (3) bony resorption, and (4) laxity of the overlying skin It naturally follows that surgical strategies aimed at rejuvenation of the lower face and neck involve correction of these signs of aging The goal of this chapter is to provide an overview of the relevant anatomy of aging, appropriate analysis of aging, and, lastly, the corrective surgical options available The reader is reminded that not all techniques for lower cervicofacial rejuvenation are covered in this chapter Less invasive procedures such as soft tissue fillers and skin resurfacing, although effective in an adjunctive role, are presented in Chapter 57, “Scar Revision and Skin Resurfacing.” Although much of this text reflects the philosophy of the authors, we have attempted to present a thorough review of the literature highlighting the many different surgical strategies available HISTORICAL PERSPECTIVE In the early part of the twentieth century, European surgeons pioneered the surgical treatment of rhytides (rhytidectomy—Greek for removal of wrinkles) By simply undermining and removing the excess skin, the subcutaneous rhytidectomy was, for nearly a half century, the gold standard for aging face surgery Unhappy with its limited duration of benefit, Skoog, in 1974, published improved, longer lasting results in the lower third of the face by dissecting in a “subfascial plane.”1 Two years later, Mitz and Peyronnie, described in detail this muscle and fascial plane of the face, naming it the superficial musculoaponeurotic system (SMAS).2 With better, longer-lasting results in the neck and jowls, the sub-SMAS procedure emerged as the new standard in facelifting techniques The literature is replete with further modifications of the SMAS rhytidectomy technique (eg, BDBK005-CH61.indd 749 deep plane,3 composite,4 triplane rhytidectomy5) as well as isolated procedures for the aging anterior part of the neck or midface, giving today’s facelift surgeon many rejuvenation options Particularly important, however, is the surgeon’s ability to recognize the differing degrees of aging from one individual to the next and to tailor the surgical strategy accordingly SURGICAL ANATOMY AND ANALYSIS OF THE AGING FACE A thorough understanding of the relevant anatomy is essential to achieving the optimal surgical result Accurate preoperative analysis of the aging anatomy should include all tissue layers of the face and neck, beginning superficially with the skin and working deep through the subcutaneous adipose, fascia layers, cervicofacial musculature, and the underlying bony framework Skin and Adipose Tissue The condition of the skin plays a significant role in the appearance of youth With aging, the skin undergoes a progressive loss of elastic and collagen fibers and a decrease in the amount of ground substance (hyaluronic acid) This results in an overall decrease in thickness and loss of elasticity allowing for the formation of rhytides Chronic sun exposure (photoaging) and habitual tobacco use greatly accelerate this process as well as contribute a coarse, leathery texture to the skin Further “sagging” of the skin can also be attributed to laxity of underlying fasciocutaneous and osteocutaneous ligaments These facial retaining ligaments allow the skin to resist downward effects of gravity by providing support from rigid underlying muscle and bone Habitual facial expressions caused by underlying mimetic muscles can also lead to progressive recontouring of the skin and subsequent rhytide formation The subcutaneous fat layer also undergoes age-related changes, demonstrating atrophy in some areas (midface) and excess accumulation in other regions (submentum) Atrophy of subdermal adipose tissue can be quite pronounced in the cervicofacial region, contributing to a gaunt, hollowed appearance in thin-faced patients With newer, more reliable methods of lipotransfer, fat can now be harvested from other areas of the body and used to augment the facial areas demonstrating atrophy Aging, as it relates to fat, can also be seen in certain facial areas where excessive accumulation occurs out of proportion to surrounding regions This is especially true of the submental region, where some individuals have a genetic propensity for undesirable fat distribution even at a relatively young age, despite normal body weight Other individuals may experience submental adipose accumulation as a direct result of progressive weight gain Either way, the end result is premature blunting of the cervicomental angle and loss of an esthetic neckline Isolated submental liposuction or open lipectomy can provide an excellent result in patients with this deformity The malar fat pad is a triangular-shaped fibrofatty thickening of subcutaneous tissue in the midface The fat pad lies immediately superficial to the SMAS, but firmly adherent to the skin and subcutaneous fat In younger individuals, the superior border of triangular fat pad lies over the malar eminence and covers the infraorbital rim Its medial border abuts the nasolabial fold, and the lateral border is approximated by a line drawn from the lateral canthus down to the corner of the mouth With advancing age and the extended effects of gravity, the malar fat pad descends by sliding over the SMAS in an inferomedial direction This ptosis can contribute to the appearance of increased fullness in the nasolabial fold, hollowness in the submalar area, and skeletonization of the orbital rim The vertical repositioning of the ptotic malar fat pad is key to restoring a youthful appearance in the aging midface Superficial Musculoaponeurotic System and Neurovascular Structures The SMAS is a fibromuscular layer investing and interlinking the muscles of facial expression As originally described, the SMAS is a facial layer superficial to and separate from the underlying parotid fascia The term musculoaponeurotic was used due to occasional muscular fibers seen in the fascia overlying the parotid Moreover, the SMAS contains fibrous septa that extend through the fat and attach to the overlying dermis As a result, the SMAS acts as a network to distribute facial muscle contractions to the skin (Figure 1).6 8/21/08 3:08:19 AM 750 PART III / Facial Plastic and Reconstructive Surgery Figure Cross section of superficial musculoaponeurotic system (SMAS) The SMAS fascial layer envelopes the muscles of facial expression Fibrous septa extend through the fat and attach to the overlying dermis to distribute facial muscle contractions to the skin (Reproduced with permission from reference 6.) Superiorly, there is a discontinuity of the SMAS at the level of the zygomatic arch because of various attachments of fascial layers at the bony arch Above the arch in the temporal region, the SMAS becomes confluent with the temporoparietal fascia Inferiorly in the neck, the SMAS represents the caudal extention of the deep layer of the superficial cervical fascia investing the platysma It is here that the extended effects of gravity on the SMAS are most often noted SMAS ptosis and age-related laxity contributes to inferiomedial platysmal migration and the development of jowls and anterior neck banding Facelift techniques that resuspend the ptotic SMAS are the primary surgical options available to correct aging in this region There are important regional variations in the relationship of the SMAS to the key neurovascular structures In the lower face and neck, the facial nerve branches are always deep to the SMAS and platysma and innervate the facial mimetic muscles through their undersurface The exception to this rule is the deep facial muscles: the levator anguli oris, the buccinator, and the mentalis, which are all innervated through their surfaces The vessels and sensory nerves in the lower part of the face similarly arise deep to the SMAS and remain at that level, except for their terminal branches These structures are thus protected if dissection is superficial to the SMAS and platysma The marginal mandiblar nerve lies deep to the platysma muscle and, therefore, is fairly well protected throughout its course along the mandible As it approaches a point cm lateral to the corner of the mouth, it becomes more superficial and dissection past this point should be avoided In the midface, the facial nerve branches are protected if dissection is superficial to the facial muscles, for example, the zygomaticus major muscle The temporal branch of the facial nerve emerges from the parotid beneath the midpoint of the zygomatic arch The nerve crosses over BDBK005-CH61.indd 750 the periosteum in a superficial plane immediately beneath the subcutaneous fat and continues superiorly on the deep surface of the temporoparietal fascia before entering the undersurface of the frontalis muscle To avoid injury to the temporal branch when elevating flaps, the dissection should be in the immediate subcutaneous plane or deep to the temporoparietal fascia The vascular supply of the lower face is, primarily, provided by branches of the external carotid artery The anterior part of the face is supplied by musculocutaneous perforators from the facial and infraorbital arteries, while the posterior part of the face receives additional blood flow from the transverse facial and postauricular branches Blood supply, as it relates to facelift surgery, is dependent on the surgical technique utilized Methods that employ more extensive subcutaneous dissection create large subcutaneous skin flaps that rely on the subdermal plexus fed by the anteriorly located facial artery Techniques, such as the deep-plane rhytidectomy, minimize subcutaneous dissection and create a composite flap of skin and SMAS that has a more robust blood supply; making it less likely to be compromised in suboptimal conditions, for example, increased wound tension and tobacco use In the cheek region, the skin and subcutaneous tissue is easily dissected free of the underlying SMAS As one continues to dissect the skin flap anteriorly, several retaining ligaments of the face are encountered (Figure 2).7 These fibrous bands are known as fasciocutaneous and osteocutaneous ligaments The faciocutaneous ligaments, particularly dense at the anterior border of the masseter muscle, emanate from the SMAS and attach to the overlying dermis The osteocutaneous ligaments are the strongest of the ligament attachments and exist between the periosteum and the overlying skin These stout ligaments emanate from the periosteum of the zygoma and mandible and are termed the zygomatic cutaneous ligaments (McGregor Figure Retaining ligaments of the face Stout osteocutaneous ligaments (large arrows) are found at the zygoma (McGregor patch) and the mandible Weaker fasciocutaneous ligaments (small arrows) are seen at the anterior border of the masseter muscle (Reproduced with permission from reference 7.) patch) and the mandibular cutaneous ligaments Release of these attachments is essential to gaining adequate mobilization of the overlying soft tissue structures such as the malar fat pad Mimetic Facial Muscles The noteworthy facial muscles important in rejuvenation of the lower face and neck are the zygomaticus major and minor and the platysma Originating superiorly at the zygoma, the zygomatic muscles insert into the modiolus and act as elevators of the corner of the mouth and lip They serve as important landmarks for deeper dissection plane techniques The zygomatic branch of the facial nerve, which innervates these muscles from their undersurface, is protected from injury when a plane of dissection superficial to the muscle is undertaken The platysma is a broad, flat sheet of muscle arising inferiorly from the fascia of the pectoralis major and the deltoid muscles Its fibers cross the clavicle and extend obliquely and upward along the side of the neck Superiorly and laterally, the fibers extend across the angle of the jaw and insert into the skin and subcutaneous tissue of the lower face as well as blend into the SMAS layer Medially, the platysmal fibers insert into muscles and subcutaneous tissue surrounding the lower part of the mouth as well as the mandibular periosteum Below the mentum, the muscle fibers from each side interdigitate and form an inverted V The apex of the inverted V is quite variable from one individual to the next, with its vertical position being at the mentum, to cm below the chin (most common) or at the level of the thyroid cartilage The platysma muscle is innervated by the cervical branch of the facial nerve, and its primary action is to depress the lower lip With aging, the medial portion of the muscle becomes lax and separates to form two diverging vertical bands Platysmaplasty is performed to correct this banding by reapproximating the muscular diastasis When this is performed in conjunction with the posterior pull of facelift, 8/21/08 3:08:20 AM CHAPTER 61 / Rejuvenation of the Lower Face and Neck a hammock-like muscular sling is recreated to restore cervicomental definition Bony Anatomy Choosing the optimal strategy for correction of cervicofacial aging requires an understanding of not only the soft tissue structures but also the bony components of the region An accurate analysis of key osseous elements should include: (1) assessment of projection and resorption of the chin/ mandible and (2) the position of the hyoid bone relative to the mandible The relationship between these two structures is key to determining the cervicomental angle, which is defined as an intersection of two cephalometric lines In the lateral view, the first line is drawn from the menton to the hyoid and the second from the hyoid to the sternal notch The ideal angle created by the intersection of these lines should approximate 90º An underprojected chin or a low, anterior hyoid can cause the angle to become more obtuse and thus less attractive Currently, there are no procedures to correct a malpositioned hyoid; therefore, patients with this configuration should be counseled on the limits this places on outcomes (Figure 3) If, however, the same patient has a small chin, surgical efforts should be directed toward chin projection as a means of improving the angle A well-defined mandibular line and chin with appropriate height and projection has certainly remained a constant esthetic ideal Perhaps the simplest way to determine ideal chin projection is to drop a vertical line from the vermillion border of lower lip If the line falls anterior to the soft tissue pogonion, then the chin is underprojected Microgenia is a term used to describe a congenital small chin with normal dental occlusion This Figure Lateral view of a patient with a poorly defined neckline The jowling and submental lipoptosis can be improved by rhytidectomy and submental liposuction, however, the primary surgical limitation is due to the anteroinferior position of the hyoid bone The prejowl sulcus is often not improved by rhytidectomy alone, and its effacement will require some form of soft tissue augmentation BDBK005-CH61.indd 751 must be distinguished from retrognathia (underprojected chin with Angle class II malocclusion) and mandibular hypoplasia (age related loss of bony projection), as the treatment options can differ between the three Microgenia and mandibular hypoplasia are more likely to be corrected by alloplastic implantation or sliding genioplasty (if also vertically deficient), whereas retrognathia often requires mandibular osteotomies and advancement The aging process can lead to varying degrees of bony resorption of the mandible (mandibular hypoplasia) The presence or absence of dentition plays a signifcant role in the amount of bone loss, especially at the alveolar ridge One specific area of age related resorption occurs between the chin and jowl that, when combined with overlying soft tissue atrophy, creates a vertical groove termed the prejowl sulcus (see Figure 3) This is of significance because although a facelift can correct jowling, it will leave the prejowl sulcus behind Specific types of extended chin implants or soft tissue fillers are often utilized to augment this atrophic region Assessment of the Neck With an understanding of the anatomy of cervicofacial aging, it is quite obvious that each individual’s face ages differently It naturally follows that the surgical approach to rejuvenation will vary from one patient to the next and that careful preoperative analysis is essential to achieve optimal results The Dedo classification system of the aging neck is a useful tool for evaluating patients for rhytidectomy8 (Figure 4).9 It identifies six classes of neck anatomy based upon the deepest affected tissue layer, that is, skin, fat, muscle, and bone A Class I neck is typically seen in younger patients with a well-defined cervicomental angle, good skin and muscle tone, and absence of submental fat A class II neck demonstrates mild skin laxity without underlying muscle or fat deformity This class of neck is rare as even early signs of aging usually occur in all tissue layers These patients are counseled that surgical correction will require wide skin undermining and some degree of lateral SMAS tightening The class III patient shows evidence of submental and submandibular fat accumulation This can either be congenital or age related Rejuvenation begins with liposuction and can also require facelifting if there is concomitant SMAS and skin laxity A class IV neck refers to anterior banding of the platysma muscle Corset platysmaplasty (anterior platysma plication) with lateral lift and suspension is utilized to correct this type of neck The class V neck reveals either a congenital microgenia of retrognathia or an age related chin hypoplasia Corrective measures should include some type of chin augmentation as previously discussed Lastly, a class VI neck is characterized by a low-lying hyoid bone with or without any of the others signs of aging These patients are counseled that there is an anatomical limitation of the result that can be achieved in the neck 751 PREOPERATIVE EVALUATION AND CONSIDERATIONS The initial consultation should begin with the patient filling out a detailed medical history questionnaire This is a quick method to ascertain important information regarding prior cosmetic procedures, medications, allergies, tobacco habits, and existing medical conditions Emphasis is placed on medical conditions that would preclude facelift surgery To maximize safety, complicated medical issues warrant appropriate preoperative clearance All medications (including herbal) that affect the body’s ability to clot, are discontinued weeks prior to surgery Because of the vasoconstrictive properties of nicotine, smokers are strongly encouraged to abstain from all forms of nicotine (including transdermal patches and chewing gum) weeks prior to surgery until weeks after A less aggressive facelift technique may be recommended to prevent tissue ischemia in a patient with a smoking history The patient is positioned in front of a mirror and asked to describe the areas of facial aging that are of concern After the patient has shared his or her concerns, the full face and neck should be examined Although the patient’s primary interest may be the lower face and neck, the upper half of the face, that is, brow and the eyelids, should also be assessed It may need to be explained to the patient that the face ages as a whole and that isolated correction of the lower third only can yield an unbalanced, unnatural appearance Working inferiorly, midfacial analysis should include bone structure as well as malar fat pad ptosis and its contribution to the nasolabial mound Examination of the lower third should include the specific areas of aging previously discussed Lastly, the quality of skin should be addressed Patients often need to be educated that, although facelift surgery can remove excess skin, it does not improve the texture of the skin Improvement of photoaged or dyschromic skin, can only be accomplished with medium to deep resurfacing techniques, topical therapy, and healthy skin care In addition to the physical examination, an accurate evaluation of the patient’s psychological status is critical to determining patient candidacy for any cosmetic operation Throughout the consultation process, the surgeon should assess the patient’s concerns, motivations and expectations to determine if these are realistic and can be met Ideally, the patient should be appropriately self-motivated and psychologically prepared for a facelift and the demands of its convalescence The consultation typically ends with the surgeon answering any questions that the patient may have It is imperative that the procedure, its risks and, benefits as well as the alternatives be fully explained to the patient prior to making any final decisions Prior to surgery, standardized rhytidectomy photographic documentation is performed in the fullface frontal, left and right oblique, and left and right lateral views An additional lateral view with the chin angled down at 30º to 45º emphasizes 8/21/08 3:08:23 AM 752 PART III / Facial Plastic and Reconstructive Surgery Class I Class IV Class II Class V posterior-superior vector of pull in the temporal and lateral brow area, while maintaining a cosmetically acceptable temporal hair tuft position at or below the helical insertion If the hairline is at or above the helical insertion point, the temporal incision made in a V-Y fashion above the helical root and then gently curved anteriorly just above the inferior border of the sideburn This configuration avoids the unnaturally raised temporal hairline seen in the “facelift cripple” (Figure 6) and can actually lower a preexisting high hairline All incisions in hair bearing skin are beveled in the direction of hair shafts to preserve follicles and allow growth of hair through the scar When planning the preauricular incision, we typically follow a retrotragal line in women and a pretragal incision in men The posttragal incision in men will displace hair-bearing skin onto the tragus which can be problematic If a scar from a prior facelift exists, this is excised; and an attempt is made to cosmetically position the new incision Postauricularly, the incision is directed mm up onto the posterior surface of the conchal cartilage, so that during healing contracture the scar ultimately falls in the sulcus and not onto the non–hair-bearing surface of the mastoid The posterior limb of the incision is gently sloped into the occipital hair at the point of posterior most projection of the pinna to maximize incision coverage in the profile view SURGICAL TECHNIQUE Because the face and neck age as a whole, many patients undergoing rhytidectomy elect to have additional facial procedures performed in combination If procedures such as browlift or blepharoplasty are indicated, these are performed prior to the facelifting Fat grafting and skin resurfacing are routinely performed after rhytidectomy By performing the facelift at or near the end of the operative sequence, we minimize the time the patient is without a compressive cervicofacial dressing Neck and Chin Class VI Class III Figure Dedo classification of the neck (Reproduced with permission from reference 9.) laxity in the submental region Closeup photos taken to document specific areas are done on an individualized basis We not routinely offer digital image morphing in our consultations but perform it upon patient request given preoperatively and are continued orally until the seventh postoperative day Intravenous dexamethasone (10 mg) and odansetron (400 mg) are also given preoperatively Facelift Incisions SURGICAL PLANNING Anesthesia and Perioperative Medications We typically perform cervicofacial rejuvenation procedures under general anesthesia, although intravenous sedation is acceptable Prophylactic intravenous antibiotics (cefazolin gm or clindamycin 600 mg if penicillin allergic) are routinely BDBK005-CH61.indd 752 There are several important considerations when planning the placement of facelift incisions The preauricular tuft of hair is the key determinant of what type of temporal hair incision we make If the tuft of hair is more than cm below the superior helical attachment, then a curvilinear incision is carried into the temporal hair in a more vertical direction (Figure 5) This allows for a greater Submental Liposuction and Platysmaplasty (Submentoplasty) The submentoplasty can be performed alone or in combination with a facelift to achieve the optimal esthetic result in the lower face and neck It is comprised of two separate procedures: submental liposuction and anterior platysmaplasty Although they are commonly performed together in the patient with an aging face, isolated submental liposuction may be all that is required for younger patients (Dedo class III) with excess adipose tissue Both liposuction and platysmaplasty are always performed before rhytidectomy, as the liposuction helps raise the neck skin flaps and the midline platyma plication is difficult if attempted after lateral SMAS/platysmal flap tightening Removal of excess submental fat has long been recognized as a relatively simple method to improve neck line esthetics The excess adipose tissue is usually located in the subcutaneous 8/21/08 3:08:24 AM CHAPTER 61 / Rejuvenation of the Lower Face and Neck 753 Figure Platysma plication sutures Beginning at the thyroid notch, buried interrupted sutures are used to approximate the medial platysma muscle edges This helps to redefine an esthetic cervicomental angle Figure Variations of facelift incisions (A) The standard retrotragal incision with temporal extension (B) Incision used to maintain temporal tuft and sideburn in stable position (C) Demonstrates the pretragal incision commonly used in male patients or patients with a deep preauricular crease or supraplatysmal layer, however, it can also accumulate deep to the platysma Numerous methods for fat removal have been described, for example, open lipectomy,10 liposuction,11 or lipo- Figure Lateral view of a patient who had a prior rhytidectomy that resulted in an unnatural appearing elevation of the temporal hair tuft There is also an area of alopecia surrounding the vertical incisional scar BDBK005-CH61.indd 753 shaving,12 with liposuction being the most commonly employed technique Preoperatively, it is important to mark the areas of fat removal with the patient sitting upright, as the appearance of submental fat changes in the supine position After induction of general anesthesia, 0.5% lidocaine and 0.25% bupivicaine with 1:200,000 epinephrine are injected under the neck skin flaps to provide both anesthesia and vasoconstriction The patient is prepped and draped, and a 15 blade is used to make cm stab incision in the submental crease A liposuction cannula (2 to mm) is introduced into the subcutaneous layer, and dry tunnels, that is, no suction applied, are made in the fanlike fashion from one inferior mandibular border to the other We recommend staying below the mandibular border as this minimizes the risk of injury to the marginal mandibular nerve Great care is also always taken to position the cannula holes facing deep, away from the skin flap as trauma to the overlying dermis can result in scarring and contour irregularities The nondominant, guide hand is used to tent up the skin as well as help advance to the tissue toward the cannula The suction (1 atmosphere negative pressure) is then applied, and fat is aspirated until the desired contour is created Some authors recommend two other stab incisions just posterior to the ear lobules to facilitate submandibular and posterior neck line contouring In younger patients with good skin tone, the overlying skin flaps typically contract down favorably to the recreated neck line, where as older, inelastic skin often requires some degree of lateral re-draping and excision to prevent contour irregularities In selected cases, where excessive submental fat deposition obscures the platysmal muscle edges or discrete subplatysmal fat pads remain after liposuction, a conservative open lipectomy with scissors may be performed When performing submental lipectomy, great care must be taken to avoid uneven cervical contour or worse yet a “cobra” deformity caused by excessive removal of fat To avoid this complication, conservative removal of fat is stressed, and the anterior platysmal borders are often suture approximated after central lipectomy is conducted In general, we perform a relatively aggressive posterior tightening of the platysma and not routinely perform anterior platysmaplasty unless significant banding is noted during preoperative examination If correction of platysmal banding is planned, the submental incision is extended to cm Using a lighted retractor and scissors, subcutaneous dissection under direct vision is performed until the medial borders of the dehiscent platysma muscle are identified The anterior muscle edges are plicated with several buried 4-0 polydiaxone sutures beginning at the thyroid notch and working superiorly to create a midline corset (Figure 7) If severe platysmal laxity is noted, the redundant edges of muscle are grasped with a clamp and excised prior to placement of sutures Meticulous hemostasis with bipolar cautery should be exercised, as even small collections of blood under the flaps during the healing phase can lead to irregular scarring and contour irregularies Despite the effectiveness of the submentoplasty, patients should be counseled about the rebound relaxation inherent to soft tissue that can lead to the reappearance of submental muscle or skin laxity Revision submentoplasty rates ranging from 15 to 50% have been reported.13,14 To combat this tissue relaxation, as well as improve neck contouring without the need for rhytidectomy, several authors have used suture techniques15 and expanded polytetrafluoroethylene 8/21/08 3:08:25 AM 754 PART III / Facial Plastic and Reconstructive Surgery cervical slings16 with good short- and long-term success Moreover, it has been our experience that patients with extremely heavy necks are the most likely to require a secondary submentoplasty during the first year after surgery An open discussion about the possibility of a “tuck-up” as a follow-up procedure certainly increases patient acceptance if such a procedure is required Chin Augmentation If surgical augmentation of the deficient chin is planned it should be performed at this time, after submentoplasty and prior to rhytidectomy As discussed previously, chin augmentation can be performed with an alloplastic implant (mentoplasty) or with a sliding genioplasty (which can correct horizontal and vertical deficiencies) As the focus of this chapter is on rejuvenation of age-related changes, we will concentrate our discussion on alloplastic mentoplasty which constitutes greater than 95% of the chin procedures in our aging face practice Decision as to what shape and size of chin implant to use should be made during the preoperative evaluation Patients with congenital microgenia who require only several milimeters of anterior projection typically have a standard chin implant (thicker in the center) inserted This type of implant, however, does not possess sufficient lateral bulk to correct the aging chin’s characteristic prejowl sulcus—a vertical groove formed between the chin and jowl as the underlying bone and soft tissue of this region atrophies (see Figure 3) The patient with microgenia and significant prejowl sulci will require an implant designed with lateral extensions intended to augment this atrophic area Currently there are several commonly used alloplastic materials (silastic, polytetrafluoroethylene, mersilene) used to construct chin implants The type of implant material chosen is ultimately dependent on the individual surgeon’s experience and preference The submental incision utilized for submentoplasty is also used for insertion of the alloplastic implant The chin is infiltrated with mL of 1% lidocaine with 1:100,000 epinephrine, and a dissection pocket approximately 10% larger than the implant is made The dissection plane is performed supraperiosteally centrally and a subperiosteally laterally, as this helps stabilize the implant and prevent migration during the healing period A more detailed description of chin augmentation is beyond the scope of this chapter and we direct the reader to the suggested reading list for further intraoperative details The submental incision is not closed until after the rhytidectomy flaps have been elevated and the lateral SMAS suspension is completed We prefer a layered closure with 5.0 polydiaxone used to approximate the subcutaneous layer and interrupted 6.0 nylon for the skin Rhytidectomy Cervicofacial rhytidectomy, or facelifting, remains the most powerful surgical procedure BDBK005-CH61.indd 754 to rejuvenate the aging lower face and neck The literature is replete with various facelifting techniques, each with advantages and disadvantages that many surgeons have debated for years and continue to so For example, there exists a school of thought that contends that a simple SMAS plication/imbrication yields more than adequate, long lasting results in the neck and jowl region However, others (we included) believe that a deeper plane of dissection produces better elevation of the ptotic midface While it is important to be familiar with these points of discussion, it must be stressed that not all patients age the same and that the optimal technique for each individual patient can vary considerably A surgical strategy that yields the best results, while minimizing unnecessary surgery and risk, should be the ultimate goal for any facelift surgeon Nearing completion of the submental and chin procedures, the right side rhytidectomy incisions and skin flap are infiltrated with 0.5% lidocaine and 0.25% bupivicaine with 1:200,000 epinephrine Timing the injection in this fashion allows for maximal anesthesia and vasoconstriction Similarly, the left side of the face should be injected prior to completion of the right side The previously delineated rhytidectomy incisions are made starting superiorly in the temporal area and continued inferiorly around the ear ending in the postauricular hairline If a vertical oriented temporal incision is chosen to improve the temporal or lateral brow region, dissection is carried down through the scalp layers to identify the temporalis fascia Undermining can be performed superficial to the deep temporal fascial layer all the way down to the lateral brow and superior border of the zygomatic arch Utilization of the sideburn sparing incision requires the dissection to be in a subcutaneous plane, so as to avoid injury to the temporal branch of the facial nerve as it crosses over the zygomatic arch Vertical retraction with skin hooks and countertraction on the flap allow for sharp facelift scissors easily to elevate the skin flap anteriorly into the cheek Transillumination of the flap with an overhead light directed through the flap allows for the identification of the proper dissection plane and aids in maintaining the appropriate flap thickness The cheek skin is typically elevated anteriorly to a line drawn between the malar eminence and the mid mandible (mandibular notch) Minimizing the extent of skin separation from the underlying SMAS creates a more vascular, composite flap that is less likely to be compromised In the occipital area, care must be taken to stay deep to the hair follicles to avoid alopecia, while staying superficial to the sternocleidomastoid fascia to prevent inadvertent injury to the great auricular nerve The cervical skin flap is elevated in the subcutaneous plane to the second major cervical rhytide and extended to the midline The subcutaneous elevation avoids injury to the marginal mandibular and cervical nerves After subcutaneous dissection is complete, manipulation of the SMAS layer is performed Figure Deep plane dissection The SMAS has been incised, the sub-SMAS dissection is carried anterior, and the zygomatic major muscle is identified Careful dissection is performed on the surface of this muscle releasing the zygomatico-cutaneous ligaments of McGregor patch to release and mobilize the malar fat pad into a posterior superior position The SMAS can be suspended by several different techniques SMAS plication is the most direct method and suspends by simply folding redundant SMAS onto itself and securing the fold with permanent sutures Imbrication of the SMAS layer involves incision and resection of lax SMAS with reapproxiamtion of the cut edges A variable amount of SMAS flap elevation can be performed prior to suture reapproximation There are still many surgeons that utilize plication or imbrication as the cornerstone of their facelift operation As stated before, we prefer a deep plane dissection that is described below Once the skin flap has been elevated, the SMAS is incised from the malar eminence to a point cm below the ear lobule Adson Brown forceps are used to grasp the anterior SMAS edge gently and a sub-SMAS dissection is continued over and anterior to the parotid by gentle, vertical spreading with scissors The zygomatic major muscle is identified and blunt dissection is performed on the surface of this muscle releasing the zygomatico-cutaneous ligaments of the McGregor patch (Figure 8) The primary goal is to release and mobilize the malar fat pad into a posterior Figure SMAS Closure The SMAS-platysmal flap has been advanced and suspended with key sutures (Xs) 8/21/08 3:08:28 AM CHAPTER 61 / Rejuvenation of the Lower Face and Neck Figure 10 Redraping the skin The anterior flap is advanced posteriorly and superiorly The posterior flap is advanced superiorly and anteriorly to recreate, without notching, the posterior hairline superior position Inferiorly the dissection is then carried deep to the platysmal muscle for approximately or cm In this region, care is taken to avoid injury to the external jugular vein, greater auricular nerve, and cervical branch of the facial nerve The SMAS-platysmal flap is then trimmed Beginning at the superior margin, a strip of SMAS is incised down to a point to cm from the free edge of SMAS anterior to the lobule This creates an inferiorly based SMAS flap that is rotated posterior to the pinna and suspended to the mastoid periosteum with interrupted 4-0 polydiaxone or 4-0 prolene sutures (Figure 9) The next suspension suture is placed from the postero-superior SMAS margin to the temporalis fascia anterior to the helical root It is this suture that repositions the malar fat pad A third fixation suture is placed at the level of the lobule The last few interrupted suspension sutures are used to fixate the free edge of platysma to the mastoid periosteum It should be stressed that a superior vector of pull on this tissue is critical to establishing a well-defined cervicomental angle The preauricular skin flap is redraped with a similar vector of pull, while the postauricular skin is draped in a more superior fashion (Figure 10) The skin closure should be tension free, as the underlying SMAS closure should provide all the support necessary for the repositioned tissue The hair-bearing skin is reapproximated with staples, and the remaining preauricular and postauricular skin is closed under minimal tension with 4-0 polydiaxone sutures buried in the deep layer and interrupted 5-0 sutures superficially (nylon for preauricular skin and chromic in the postauricular skin) A 5-0 polydiaxone suture placed from the pretragal soft tissue to the overlying dermis recreates the pretragal crease The skin advanced over the tragus is thinned, and a 6-0 fast absorbing gut suture is used to close the post-tragal incision We not routinely use drains At the conclusion of the procedure, white petrolatum is applied to the suture lines and petroleum smeared BDBK005-CH61.indd 755 cotton balls are placed in the conchal bowls Nonadherent Telfa gauze is placed over the incisions, and a bulky cotton/kerlex compression dressing is applied An example of an excellent candidate for a deep plane facelift is depicted in Figure 11 Preoperatively, this surgical candidate would be categorized as a Class IV using the previously described Dedo classification: skin laxity, SMAS and platysmal laxity, mild excessive submental fat, anterior platysmal banding, adequate chin projection, and normal hyoid positioning The patient underwent a deep plane facelift, submental liposuction, and platysmaplasty to address the above concerns The deep plane approach was chosen in particular to elevate the ptotic malar fat pad and improve the midface and malar regions The patient also underwent concomitant upper face rejuvenation including upper lid blepharoplasty and endoscopic browlift POSTOPERATIVE CARE On postoperative day one, the dressing is removed and flap viability is assessed If any small collections of serosanguinous fluid or clot are palpated these are gently expressed through the postauricular incision A new lighter dressing is applied and left in place until the third postoperative day The patient is then instructed to wear a commercial elastic dressing around the clock for the remainder of the first week after the operation During this period, a regimen of cleaning the incision lines and reappyling white petrolatum is performed several times a day The patient is allowed to shower and gently wash the hair starting the third day after surgery For the first 72 hours after the operation, head of bed elevation is encouraged and cold compresses are applied to the face and neck at intervals of 20 minutes on and 20 minutes off Oral antibiotics are continued for a total of days The patient is seen for their second postoperative visit on day 6, at which time the submental sutures, preauricular sutures, and skin staples are removed The postauricular chromic sutures are left in place to dissolve The patient is asked to continue wearing the elastic facelift wrap at night for an additional weeks We routinely remind the patients that ecchymosis typically resolves in weeks and that the majority of edema dissipates over to weeks Routine follow-up visits are scheduled at 1, 3, 6, and 12 months after the operation A consultation with our estheticians is also helpful for postoperative skin care and makeup recommendations COMPLICATIONS AND THEIR MANAGEMENT Major complications following rhytidectomy are relatively uncommon However, due to the elective nature of the procedure any complications, major or minor, are poorly tolerated by both patient and surgeon All surgeons who per- 755 form rhytidectomy should preoperatively inform their patients of the potential risks, including hematoma, infection, skin flap necrosis, nerve injury, poor scarring, alopecia, ear lobe deformity, and parotid gland injury Hematoma The most common complication after rhytidectomy is formation of hematoma, occurring in to 15% of patients.17 Risk factors for hematoma formation include hypertension and usage of products that inhibit platelet or clotting function, for example, aspirin, nonsteroidal anti-inflammatory drugs, and vitamin E Postoperative vomiting and coughing can also predispose to bleeding Male patients tend to have a higher incidence of hematoma formation, which is thought to be due to an increased blood supply to the hair follicles of the bearded skin The majority of reported hematomas are minor, small collections of fluid or clot that are identified in the first week after surgery Often these can be managed by removing one or two of the postauricular sutures and gently expressing the clot If the clot has already liquefied then an 18gauge needle can be used to aspirate the collection Unrecognized small collections can lead to infection, scarring, and skin discoloration Major hematomas requiring exploration and drainage usually occur within the first 12 hours after the operation Clinical signs and symptoms include increasing unilateral pain, edema, skin flap ecchymosis, and bleeding from the incisions In cases where treatment is delayed, pressure under the flaps can lead to skin necrosis Treatment should include immediate clot evacuation, irrigation, and identification and cautery of bleeding vessel(s) In our experience, it is often difficult to identify one discrete vessel, rather there is a diffuse oozing that requires careful cautery of many suspicious sites in the dissection bed A compressive dressing is reapplied, and the patient is reevaluted the following morning Infection The rich facial blood supply and the routine use of prophylactic antibiotics are the principal reasons that postrhytidectomy infection is seldom seen In the rare case of frank abscess formation, drainage, culture, and broad-spectrum oral or intravenous antibiotics should be implemented as indicated Skin Flap Necrosis Rhytidectomy skin flaps receive their blood supply through the subdermal plexus in a random fashion Compromise of this vascular supply can lead to necrosis and loss of skin, most commonly seen in the distal portion of the flaps, that is, periauricular skin Risk factors include excessive thinning of the flap, excessive closure tension, hematoma, smoking, and systemic disorders, for example, diabetes mellitus Techniques such as the deep-plane rhytidectomy theoretically should have less risk of flap complications 8/21/08 3:08:29 AM 756 PART III / Facial Plastic and Reconstructive Surgery (A) (B) (C) (D) (E) (F) Figure 11 Preoperative (A, B, C) and postoperative (D, E, F) frontal, oblique and lateral views of a middle-aged woman who underwent deep plane rhytidectomy, plastysmaplasty, submental liposuction, endoscopic browlift, and upper lid blepharoplasty The deep plane dissection has elevated the ptotic malar fat pad and produced improvement of the midface and malar region due to a better vascularized composite flap and closure tension placed on the deeper SMAS layer Cyanosis often precedes flap necrosis If this is recognized early enough, it is potentially reversible Partial-thickness skin loss can be treated conservatively with occlusive dressings or ointments Full-thickness necrosis should be managed with limited debridement of devitalized tissue and local care to provide the best conditions for healing by secondary intention These areas BDBK005-CH61.indd 756 often heal well but certainly carry an increased risk of undesirable scarring Nerve Damage The most commonly injured sensory nerve is the great auricular nerve, occurring in up to 7% of cases.18 The nerve, along with the external jugular vein, crosses the anterior border of the sternocleidomastoid muscle several centimeters below the angle of mandible Injury to the nerve can occur when attempting to obtain hemostasis from inadvertent injury to the vein If the nerve is transected, an end-to-end anastomosis with epineural repair should be attempted Failure to repair such as injury can result in formation of a painful neuroma Injury to this nerve is often permanent, however, the affected sensory area usually decreases over time Injury to motor branches of the facial nerve is far less common, occurring in 0.5 to 2.6%.17 Injuries of the temporal and marginal mandibular branches are the two most often reported The 8/21/08 3:08:30 AM CHAPTER 61 / Rejuvenation of the Lower Face and Neck buccal branches are also susceptible to injury when extended dissection techniques, for example, deep-plane lift, are used The cervical branch can be injured while mobilizing the lateral edge of the platysma muscle resulting in a “pseudomarginal” nerve paresis Damage to the cervical branch can be distinguished from marginal mandibular nerve injury by the fact that the patient will be able to evert the lower lip due to a functioning mentalis muscle As mentioned earlier in this chapter, a thorough understanding of the facial nerve anatomy can help avoid these complications Fortunately, the majority of nerve injuries are neurapraxic in nature This temporary paresis often resolves over the first few months after injury In our experience, the majority of immediate postoperative paralysis or paresis is due to local anesthetic effects, which dissipate in several hours Hypertrophic Scarring Excessive skin closure tension is commonly regarded as the primary cause of hypertrophic scars after rhytidectomy Other predisposing factors include race, skin type, and prior history of abnormal scarring Most commonly located in the postauricular region, these scars usually develop in the first months after the operation Initial treatment consists of intralesional corticosteroid injections (triamcinolone to 10 mg/mL) at 3week intervals Excision of these scars should be delayed for to 12 months, and potential recurrence of lesions can be lessened with judicious use of deep sutures Alopecia and Ear Lobe Deformity Alopecia is usually due to excessive closure line tension causing transient shock of the hair follicles Patients are reassured that recovery is usually within to months If follicles not BDBK005-CH61.indd 757 fully recover, the hairless skin can be excised and closed primarily The use of hair transplantation techniques can also be employed to fill in bare areas or restore loss of the temporal tuft Post-rhytidectomy ear lobe deformity (pixie ear) can be a sequela of poor incision placement, malpositioning of the lobule at closure, and tension on the closure Correction of this complication can be challenging, often requiring an advancement flap technique with closure tension supported by deeper layers Parotid Injury Inadvertent injury to the parotid gland can occur during SMAS flap or platysma elevation The subsequent formation of a glandular pseudocyst (sialocele) or salivary fistula is seldom seen but is a potential concern If parotid parenchyma is exposed during the dissection, the overlying fascia should be sewn over the defect Postoperative seroma formation in the area of the mandibular angle should raise suspicion of sialocele formation Conservative treatment with oral anticholinergics, serial aspirations, and pressure dressing are recommended Recurrent collections may require surgical exploration and placement of a suction drain CONCLUSIONS Performed alone or in combination, procedures such as submental liposuction, platysmaplasty, chin augmentation, and rhytidectomy can provide a dramatic rejuvenation of the lower face and neck A thorough understanding of the relevant anatomy coupled with an accurate preoperative analysis of the aging anatomy is essential to determining which procedures are to be recommended as well as achieving the optimal surgical result 757 REFERENCES Skoog T Plastic surgery: The aging face In: Skoog TG, editor Plastic Surgery: New Methods and Refinements Philadelphia: WB Saunders; 1974 p 300–30 Mitz V, Peyronie M The superficial musculoaponeurotic system (SMAS) in the parotid and cheek area Plast Reconstr Surg 1976;58:80–8 Hamra ST The deep-plane rhytidectomy Plast Reconstr Surg 1990;86:53–61 Hamra ST Composite rhytidectomy Plast Reconstr Surg 1992;90:1–13 Baker SR Tri-plane rhytidectomy Arch Otol Head Surg 1997;123:1167–72 Larrabee WF, Makielski KH, Henderson JL Surgical Anatomy of the Face, 2nd edition Philadelphia: Lippincott Williams and Wilkins; 2004 p 50 Larrabee WF, Makielski KH, Sykes J Surgical anatomy for endoscopic facial surgery In: Keller GS, editor Endoscopic Facial Plastic Surgery St Louis: Mosby; 1997 p 28 Dedo DD A preoperative classification of the neck for cervicofacial rhytidectomy Laryngoscope 1980;90:1894–6 Larrabee WF, Makielski KH, Henderson JL Surgical Anatomy of the Face, 2nd edition Philadelphia Lippincott Williams and Wilkins; 2004 p 26 10 Millard DR, Jr, Garst WP, Beck RL, Thompson ID Submental and submandibular lipectomy in conjunction with a facelift, in the male or female Plast Reconstr Surg 1972;49:385–91 11 Illouz Y-G Body contouring by lipolysis: A 5-year experience with over 3000 cases Plast Reconstr Surg 1983;72:591–7 12 Becker DG, Cook TA, Wang TD, et al A 3-year multiinstitutional experience with the liposhaver Arch Fac Plast Surg 1999;1:171–6 13 Perkins SW, Gibson B Use of submentoplasty to enhance cervical recontouring in face-lift surgery Arch Otolaryngol Head Neck Surg 1993;119:179–83 14 Kamer FM, Frankel AS Isolated submentoplasty: A limited approach to the aging neck Arch Otolaryngol Head Neck Surg 1997;123:66–70 15 Giampapa VC, DiBernardo BE Neck recontouring with suture suspension and liposuction: An alternative for the early rhytidectomy candidate Aesthetic Plast Surg 1995;19:217–23 16 Prabhat A, Dyer WK Improving surgery on the aging neck with an adjustable expanded polytetrafluoroethylene cervical sling Arch Fac Plast Surg 2003;5:491–501 17 Sullivan CA, Masin J, Maniglia AJ, Stepnick DW Complications of rhytidectomy in an otolaryngology training program Laryngoscope 1999;109:198–203 18 Pitanguy I, Cervello MP, Degand M Nerve injuries during rhytidectomy: Considerations after 3,203 cases Aesthetic Plast Surg 1980;4:257–65 8/21/08 3:08:48 AM BDBK005-CH61.indd 758 8/21/08 3:08:48 AM ...Ballenger_FM.qxd 8 /11 /08 9:58 AM Page i Ballenger’s OTORHINOLARYNGOLOGY1 7 HEAD AND NECK SURGERY Ballenger_FM.qxd 8 /11 /08 9:58 AM Page ii Ballenger_FM.qxd 8 /11 /08 9:58 AM Page iii Ballenger’s OTORHINOLARYNGOLOGY1 7... MD Professor and Chief Division of Otolaryngology Head and Neck Surgery Department of Surgery Southern Illinois University Springfield, Illinois RHINOLOGY HEAD AND NECK SURGERY Andrew P Lane,... 17 3 xiii Ballenger_FM.qxd 8/22/08 1: 45 AM Page xiv xiv 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Contents Outcomes Research, Clinical Trials and Clinical Research