Operative Techniques in Laryngology [2 ed.] 3031343530, 9783031343537

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Clark A. Rosen C. Blake Simpson

Operative Techniques in Laryngology Second Edition

Operative Techniques in Laryngology

Clark A. Rosen • C. Blake Simpson

Operative Techniques in Laryngology Second Edition

Clark A. Rosen UCSF Voice & Swallowing Center Department of Otolaryngology-Head & Neck Surgery University of California, San Francisco San Francisco, CA, USA

C. Blake Simpson Department of Otolaryngology—Head and Neck Surgery University of Alabama at Birmingham Birmingham, AL, USA

ISBN 978-3-031-34353-7    ISBN 978-3-031-34354-4 (eBook) https://doi.org/10.1007/978-3-031-34354-4 © Springer Nature Switzerland AG 2008, 2024 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publisher, the authors, and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, expressed or implied, with respect to the material contained herein or for any errors or omissions that may have been made. The publisher remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. This Springer imprint is published by the registered company Springer Nature Switzerland AG The registered company address is: Gewerbestrasse 11, 6330 Cham, Switzerland

When given the opportunity to reflect on how I came to be part of this book project, I realize that I have been so lucky and blessed to have the good fortune of love from my friends and family, mentorship, and exposure to amazing role models. It is a sheer joy to dedicate this book to these individuals that have led, shaped, and cajoled me to this point in my life. My parents, Shirley and Paul Rosen, provided me with so much. My mother instilled a quest for excellence in me, and my father demonstrated the importance and value of “bedside manner” to me. Thank you both; I miss you every day. Professionally I am in debt to so many amazing people who have taught me, been a role model for me, and believed in me. This list is too long to enumerate, but I am compelled to acknowledge: James I. Cohen, MD, PhD, who believed in me when many did not and provided me a view into surgical and clinical care excellence; Gayle E. Woodson, MD, who opened the door of laryngology for me; and Eugene N. Myers, MD, who gave me the chance to build a vision of high-quality laryngology care, education, and science. I am indebted to the amazing teammates that I have had the pleasure of working with over the years: Thomas Murry, PhD; Robert Buckmire, MD; Lori Lombard, PhD; Jackie Gartner-Schmidt, PhD; Amanda Gillespie, PhD; Priya Krishna, MD; Libby Smith, DO; VyVy Young, MD; Yue Ma, MD; and Sarah Schneider, MS. These people and so many more have taught me and shouldered the awesome responsibility of caring for those in need and advancing the field of laryngology side by side with me. I am so grateful to have taken this journey with them. Thank you from the bottom of my heart. I am so glad to mention the incredible gifts of learning and friendship that I have received from my past laryngology fellows: Apurva Thekdi, MD; TK Kwon, MD; Priya Krishna, MD; Michiel Bove, MD; Thomas Carroll, MD; Johnny Sok, MD, PhD; Melissa Statham, MD; VyVy Young, MD; Pavan Mallur, MD; John Ingle, MD; Adrienne Wong, MD; Shaum Sridharan, MD; Lyndsay Madden, DO; R Jun Lin, MD; Helen Wang, MD; Daniel Cates, MD; Andree-Anne Leclerc, MD; Christopher Dwyer, MD; and David Bracken, MD. I have learned so much from and extend my deepest gratitude to each of you. Love you all.

I have had the benefit of collaborating with several special people in the care of laryngology patients and development of my surgical practice. Thank you to Susan Rusyn and Colleen Picinotti. Your dedication to patient care and surgical innovation is very special. So much of the content of this book derives from your support, creativity, and partnership. My peer support has been truly spectacular. Each of these amazing men has supported, taught, and served as an inspiration to me: Milan Amin, MD; Peter Belafsky, MD, PhD; Mark Courey, MD; Michael Johns III, MD; Albert Merati, MD; Greg Postma, MD; and Lucian Sulica, MD. Thank you. Many years ago, I found myself taking a hike with a laryngology colleague while playing hooky during COSM in Palm Springs. As we walked, we discussed family, friends, and work. During the hike, we came up with the idea of writing a surgical atlas of laryngeal surgery. Since that pivotal day in the desert, Blake Simpson, MD, has taught me more about laryngology and patience than any other one person has. I am eternally grateful for his friendship, energy, intellect, and his amazing ability to put up with my limitations. Thank you, Blake. Sincerely and with deepest gratitude. Clark A. Rosen San Francisco, California December 2022

This book is dedicated to my two favorite people in the world: 1. My father, C. B. Simpson, MD, who inspired me to become a doctor and instilled in me discipline and hard work. 2. My amazing wife, my soulmate, my muse: Michelle Simpson. I love you. I would like to thank the numerous individuals who have influenced my career over the years. I am eternally grateful to my mentors from residency training, including my chairman and master surgeon Jesus Medina, MD, Keith Clark, MD, who steered me to laryngology early in my residency, and my fellowship director, Robert “The Boss” Ossoff, MD, who has been an incredibly kind and supportive mentor over the years. I would not be in laryngology or academic medicine without these incredible role models. Over the years, I have had the good fortune to learn from some of the most experienced and thoughtful senior clinicians in our field, including Peak Woo, MD; Jim Netterville, MD; Robert Bastian, MD; Robert Sataloff, MD; György Lichtenberger, MD; and Robert Toohill, MD, to name a few. These pioneers were academically prolific long before formal fellowship training in laryngology began in the early 1990s and were among a handful of physicians who blazed the trail for our subspecialty. In the latter part of my career, I was honored to partner with an amazing speech pathologist, Edie Hapner, PhD. Dr. Hapner is without a doubt the most astute clinician I have ever worked with and made me better just being in her presence. I would also like to thank the dozens of exceptional residents and laryngology fellows I’ve had the good fortune of training over the last quarter of a century at UT Health San Antonio and the University of Alabama-Birmingham. I started training laryngology fellows in 2008 and have been incredibly lucky to consider these amazing physicians my mentees and friends: Mike King, Laura Matrka, Jeanne Hatcher, Laura Dominguez, Kathleen Tibbetts, Mike Loochtan, Alissa Collins, Patrick McGarey, Randy Holdgraf, Matt Hoffman, Manish Shaha, Malia Gresham, and hopefully a few more before I hang it up. These physicians have had a profound impact on my career and I am eternally grateful. It’s my fellows I will miss the most when I one day retire.

I would also like to thank all my patients over the years who have allowed me to take care of them. It is not lost on me the incredible degree of trust our patients must have in us to guide their care. None of the advances in laryngology over the past two decades would have occurred without these brave individuals consenting to novel and investigatory therapies. It’s been an honor to take care of so many wonderful people. The doctor-patient relationships that span over decades are truly one of the highlights of a long career. Finally, I am quite fortunate to have collaborated with an exceptional group of colleagues who have been instrumental in shaping and guiding our field over the past 25-plus years: Albert Merati, MD; Lucian Sulica, MD; Mark Courey, MD; Greg Postma, MD; Milan Amin, MD; Peter Belafsky, MD; and Michael Johns III, MD. I’m privileged to call them my friends. Last but not least, my coauthor and partner in crime, Clark Rosen, MD. It’s hard to imagine my academic career without him. He has been an exceptional collaborator, confidant, mentor, teacher, and friend. This book has entwined our lives for the better part of 20 years, and it will always be the academic achievement I’m most proud of when it’s all said and done. Blake Simpson Birmingham, AL December 2022

Foreword to the First Edition

In this age of communication, the care of the human voice and the vocal organ has assumed greater and greater importance. The maintenance of good vocal health and the treatment of the diseased larynx are essential for all members of society—from heads of state to the receptionist with the golden voice on the telephone. The necessity for the restoration of pathologic changes in the larynx has resulted in the application of numerous operative techniques, which may bewilder the clinician. There is a real need for a comprehensive educational resource like Operative Techniques in Laryngology. The two authors of this textbook, Clark A.  Rosen and C.  Blake Simpson, both leading scholars and experienced surgeons at major medical centers, have created a superb treatise, which expertly details the surgical care of different laryngeal pathologies. The introductory chapters call attention to the current methods of clinical evaluation for laryngeal disorders, including videostroboscopy and flexible laryngoscopy, as well as the medical treatment of patients with vocal problems. The indicated preoperative measures are discussed in detail, and the importance of anesthesia and airway management during surgical procedures within the larynx are stressed. Subsequent chapters advance the reader from the fundamental principles of laryngeal surgery to major surgical techniques such as phonomicrosurgery, laser surgery, vocal fold augmentation, and surgery of the laryngeal framework. In successive chapters, each pathologic entity is presented in detail, including the etiology, history, vocal quality, physical examination, surgical intervention, postoperative care, and potential complications. Specific microsurgical procedures are recommended for all common benign lesions and for localized neoplasms of the vocal folds. The use of lasers is described for stenosis of the vocal folds and circumscribed malignant lesions. The chapters on vocal fold augmentation include precise information on injection techniques via microlaryngoscopy, as well as peroral and percutaneous approaches. Specific chapters are devoted to the principles of operative care for laryngeal framework surgery. These procedures range from medialization laryngoplasty or arytenoid adduction to more complex problems such as cricothyroid subluxation, laryngeal fractures, sulcus deformity of the vocal fold, and stenosis of the larynx and trachea. The reader will be impressed with the clarity of the presentations, which is enhanced by the use of systematic headings and by the precision and the rich color of the illustrations within each chapter. An abundance of carefully selected references enables the prospective surgeon to pursue further detailed information from various experts as desired. It is apparent that the authors and the publisher have combined their expertise to present an outstanding educational and inspirational textbook for both the clinical otorhinolaryngologist and the experienced laryngeal surgeon. I shall cherish my own copy of this exciting edition. University of Southern California Los Angeles, CA, USA February 2008

Hans von Leden,

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Foreword to the Second Edition

Anyone entering laryngology today may be forgiven for thinking that the field has always been a full-fledged subspecialty of otolaryngology alongside otology, head and neck surgery, and others. In large part, that is because of the first edition of Operative Techniques and a handful of other, essential publications which appeared within a few years of one another, which together created the foundation of modern laryngology. Thanks to these, laryngology has a well-defined body of knowledge, robust literature, clear goals of subspecialty training, and other features that define a mature area of medicine. But the flowering of laryngology is—improbably—recent, within my professional lifetime. “Improbably,” because laryngology, along with otology, rhinology, and ophthalmology led the way to specialization more than a century ago, propelled by the opportunity to perform an array of procedures in the awake patient created by the relative accessibility of the larynx and the advent of topical mucosal anesthesia. However, the advent of the antibiotic era brought the disappearance of the bulk of the disease burden faced by early laryngologists—pick up a laryngology text from 100 years ago, and syphilis and tuberculosis take up well over half the pages. The rebirth of the field owes a great deal to the passionate practitioners who kept it alive during the decades when it was on the periphery, and who inspired a generation of residents to take up the banner. Drs. Rosen and Simpson have been notable among this group of new laryngologists. With this volume, they set out to establish the surgical canon for the renewed subspecialty, the repertoire of operations that defined the scope of practice for the twenty-first-­ century laryngologist. The first edition of Operative Techniques did that with verve. The figures themselves set the volume apart, not only carefully synchronized with the text, and in orientations that made sense surgically, but in abundant quantity and with colorful detail and a crisp line that made the volume the most aesthetically pleasing atlas since Dedo’s Surgery of the Larynx and Trachea and Johns, Price, and Mattox’s Atlas of Head & Neck Surgery of 1990. The text provided essential surgical detail in abundance and proved just as valuable the first time one performed an operation as the second or the fifth, yielding more detail and nuance each time the reader returned to it with practical experience. The second edition builds on the first, incorporating a larger cast of contributors and recent areas of surgical innovation that reflect the development of the field in the decade and a half since its predecessor. Notably, these include awake laryngeal surgery, a resurrection of early practice in laryngology which has changed the face of patient care for laryngeal disorders in an astonishingly short period of time. Gender-affirming surgery and surgery for swallowing disorders are also included. All of these are accompanied by a significant body of new artwork. Finally, the authors have made space for the increasingly sophisticated discourse in laryngology by including commentary from subject specialists alongside the main text, highlighting particularly important points, or areas in which there exists disagreement. It’s an important step away from dogma that limits innovation and original thinking, and an acknowledgment that laryngology has many voices. I’ve been fortunate to have lived and worked through an intellectually exciting period in laryngology and privileged to have shared it with colleagues like Clark and Blake, who have xi

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been energetic builders with vision and the drive to share it with others. Operative Techniques in Laryngology, Second Edition captures the depth and breadth of their achievement and cannot help but serve as an inspiration and a springboard for the future. Lucian Sulica Sean Parker Institute for the Voice New York, NY, USA Department of Otolaryngology—Head and Neck Surgery Weill Cornell Medical College New York, NY, USA January 2022

Foreword to the Second Edition

Preface

The field of laryngeal surgery for voice, swallowing, and airway pathologic conditions has dramatically changed over the last 20 years, and the impetus for this book was to reflect these major paradigm shifts and bring together in one place essential information on the rapidly growing and changing field of laryngeal surgery. The book was written to provide the laryngeal surgeon with: (1) essential background information in laryngological disorders, (2) step-by-­ step surgical information for laryngeal surgery, and (3) key pearls and pitfalls about indications, surgical steps, and (4) postoperative management of laryngeal surgeries. The essential background materials provided support our belief that a true surgeon should be a physician first, and must always approach each patient in a holistic manner, and thus understand the essential anatomy and pathology of laryngological disorders, as well as the nonsurgical treatment modalities. This supports the concept of holistic laryngology medicine, not just laryngeal surgery. The book encompasses a wide range of laryngeal procedures, and it has been organized around the broad categories of Clinical Evaluation of Laryngeal Disorders, Phonomicrosurgery, Awake Laryngeal Surgery, Laryngeal Framework Surgery, and Open Airway Reconstruction. Within phonomicrosurgery, detailed information is provided regarding surgery for a wide variety of benign vocal fold lesions, vocal fold augmentation, endolaryngeal airway surgery, and laser laryngeal surgery. The laryngeal framework surgery sections include essential chapters on “open” treatment for unilateral vocal fold paralysis, bilateral vocal fold paralysis, laryngeal trauma, airway stenosis (glottic, subglottic, and tracheal), and vocal fold scar/sulcus deformity of the vocal fold. Awake laryngologic surgery has greatly expanded the ability of the laryngologist to help our patients with voice, swallowing, and breathing difficulties. Several new chapters have been added to this edition of the book to provide guidance on these very rewarding and vital surgical procedures. Surgery for dysphagia is a rapidly growing area of our specialty, and there are five new chapters dedicated to helping our patients suffering from dysphagia. Recent advances in laryngeal care for transgender patients have been included in this edition and a chapter on performing a SLN block. All the chapters have been designed to allow the reader to understand indications, contraindications, equipment required, step-by-step aspects of the procedure, perioperative care, and management of complications. In almost every chapter, one will find important insights or pearls that, until now, have only been taught verbally by mentor to student. We hope that this book will become essential reading for all students and practitioners of laryngology, and general otolaryngologists performing laryngeal surgery. In addition to expanding the number of chapters from 48 to 67, in most surgery-specific chapters we have invited a master Laryngologist to provide a “different insight” on the topic in the form of a Commentary. The material of the Commentary has been purposely placed within the body of the chapter to allow the reader to gain perspective on the surgery and nuanced differences of opinion of the commentator. We hope that the Commentary will provide the reader with a greater breath and range on surgical decision-making, techniques, and approaches. We are deeply indebted to our wonderful and talented colleagues who provided their expertise, experience, and thought processes. xiii

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Preface

We have written or contributed to most of the chapters of this book; however, for selected chapters, we have been honored to have leaders in our field with whom we collaborated. We would like to thank all these truly gifted laryngologists for sharing their knowledge and expertise. This surgical atlas is richly illustrated with detailed, colorful artwork supplemented by clinical photographs, and new in the second edition educational video clips have been added to enhance the reader’s comprehension. In closing, we feel that this book brings together a wide variety of new and exciting surgical procedures involving the larynx, upper airway, and esophagus. We hope that this second edition assists the laryngeal surgeon in the care of patients with voice, airway, and swallowing disorders and assists with the growth of our field. San Francisco, CA, USA Birmingham, AL, USA 

Clark A. Rosen C. Blake Simpson

Acknowledgments

The authors wish to express thanks to the following companies for their financial support in the making of both the first and second editions of this book: Bryan Medical Olympus Surgical Medtronic ENT Kay Pentax Karl Storz Endoscopy America Integra LifeSciences The authors would like to thank David Baker, the senior illustrator for both the first and second editions of this book. Mr. Baker is an exceptionally talented medical illustrator and artist who has produced hundreds of outstanding illustrations for Operative Techniques in Laryngology over the past two decades. His illustrations were vital to the success of the first edition, and the authors convinced Mr. Baker to come out of retirement to complete the illustrations for the second edition. The process of producing medical illustrations is painstaking, time intensive, and required a great deal of collaboration between the illustrator and the authors of this book. We are grateful for Mr. Baker’s dedication to the project and delighted to preserve the continuity of illustration styles between the first and second editions. Other outstanding illustrators who worked on both editions include David Aten, Chris McKee, and Susan Simon. The authors would also like to thank our editor, Michael Wilt, who cajoled us to keep this project going over many years.

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Contents

Part I Clinical Evaluation of Laryngeal Disorders 1 Anatomy  and Physiology of the Larynx�������������������������������������������������������������������   3 Hagit Shoffel-Havakuk and Michael M. Johns III 2 Principles  of Clinical Evaluation for Voice Disorders���������������������������������������������  11 Phillip C. Song and VyVy N. Young 3 Videostroboscopy  and Dynamic Voice Evaluation with Flexible Laryngoscopy �������������������������������������������������������������������������������������������������������������  17 Clark A. Rosen and C. Blake Simpson 4 Pathological  Conditions of the Vocal Fold ���������������������������������������������������������������  23 Laura Dominguez, Clark A. Rosen, and C. Blake Simpson 5 Glottic  Insufficiency: Vocal Fold Paralysis, Paresis, and Atrophy�������������������������  33 C. Blake Simpson and Clark A. Rosen 6 Glottic  and Subglottic Stenosis: Evaluation and Surgical Planning ���������������������  43 C. Blake Simpson and Clark A. Rosen 7 Nonsurgical Treatment of Voice Disorders���������������������������������������������������������������  51 Priya Krishna and Clark A. Rosen 8 Laryngopharyngeal Reflux Disease���������������������������������������������������������������������������  61 Thomas L. Carroll and Matthew R. Naunheim 9 Timing,  Planning, and Decision-Making in Phonosurgery�������������������������������������  69 Clark A. Rosen and C. Blake Simpson 10 Anesthesia  and Airway Management for Laryngeal Surgery: Surgeon’s Perspective�������������������������������������������������������������������������������������������������  73 Karen J. Maresch, Clark A. Rosen, and C. Blake Simpson 11 Anesthesia  and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective�������������������������������������������������������������������������������������������������������������������  89 Karen J. Maresch, Clark A. Rosen, and George W. Pasvankas Part II Phonomicrosurgery for Benign Laryngeal Pathology: Principles 12 Principles of Phonomicrosurgery ����������������������������������������������������������������������������� 107 Clark A. Rosen and C. Blake Simpson 13 Ergonomics of Phonomicrosurgery��������������������������������������������������������������������������� 123 Libby J. Smith and Clark A. Rosen 14 Perioperative  Care for Phonomicrosurgery������������������������������������������������������������� 131 Clark A. Rosen and C. Blake Simpson xvii

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15 Management  and Prevention of Complications Related to Phonomicrosurgery����������������������������������������������������������������������������������������������������� 135 C. Blake Simpson and Clark A. Rosen 16 Principles  of Laser Microlaryngoscopy ������������������������������������������������������������������� 139 Clark A. Rosen and C. Blake Simpson 17 Principles of Vocal Fold Augmentation��������������������������������������������������������������������� 147 Clark A. Rosen and C. Blake Simpson Part III Phonomicrosurgery for Benign Laryngeal Pathology: Voice Procedures 18 Vocal  Fold Polyp and Reactive Lesion: Phonomicrosurgery ��������������������������������� 155 C. Blake Simpson and Clark A. Rosen 19 Vocal  Fold Cyst and Vocal Fold Fibrous Mass��������������������������������������������������������� 165 Clark A. Rosen and C. Blake Simpson 20 Reinke’s Edema����������������������������������������������������������������������������������������������������������� 173 C. Blake Simpson and Clark A. Rosen 21 Vocal Fold Granuloma����������������������������������������������������������������������������������������������� 179 Clark A. Rosen and C. Blake Simpson 22 Vocal  Fold Leukoplakia and Epithelial Dysplasia: Phonomicrosurgery��������������� 185 C. Blake Simpson and Clark A. Rosen 23 Surgical  Treatment of Recurrent Respiratory Papillomatosis of the Larynx������� 191 Clark A. Rosen and C. Blake Simpson 24 Vascular  Lesions of the Vocal Fold: Phonomicrosurgery��������������������������������������� 199 Robert Thayer Sataloff and Clark A. Rosen 25 Vocal  Fold Scar and Sulcus Deformities of the Vocal Fold������������������������������������� 207 Clark A. Rosen and C. Blake Simpson 26 Endoscopic  Management of Teflon Granuloma������������������������������������������������������� 219 C. Blake Simpson and Clark A. Rosen 27 Endoscopic  Excision of Saccular Cyst���������������������������������������������������������������������� 225 C. Blake Simpson and Clark A. Rosen 28 Anterior Glottic Web ������������������������������������������������������������������������������������������������� 231 Clark A. Rosen and C. Blake Simpson 29 Buccal  Mucosal Grafting in the Larynx������������������������������������������������������������������� 239 Peak Woo 30 Vocal Fold Augmentation: Phonomicrosurgery������������������������������������������������������� 247 Clark A. Rosen and C. Blake Simpson 31 Superficial Vocal Fold Injection��������������������������������������������������������������������������������� 257 Clark A. Rosen and C. Blake Simpson Part IV Phonomicrosurgery for Benign Laryngeal Pathology: Laser Microlaryngeal Surgery (Airway/Neoplastic Conditions) 32 Bilateral Vocal Fold Paralysis ����������������������������������������������������������������������������������� 263 Clark A. Rosen and C. Blake Simpson

Contents

Contents

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33 Posterior  Glottic Stenosis: Endoscopic Approach��������������������������������������������������� 275 C. Blake Simpson, Clark A. Rosen, Mark S. Courey, László Rovó, Alexander Gelbard, and Christopher T. Wootten 34 Subglottic/Tracheal  Stenosis: Endoscopic Management����������������������������������������� 289 C. Blake Simpson, Patrick O. McGarey Jr, and Clark A. Rosen 35 Carcinoma  of the Vocal Fold ������������������������������������������������������������������������������������� 305 Andrew J. McWhorter, C. Blake Simpson, and Clark A. Rosen Part V Awake Laryngeal Procedures 36 Principles  of Awake Laryngeal Procedures ������������������������������������������������������������� 319 C. Blake Simpson and Clark A. Rosen 37 Per-oral Vocal Fold Augmentation����������������������������������������������������������������������������� 327 Clark A. Rosen and C. Blake Simpson 38 Awake Percutaneous Vocal Fold Augmentation������������������������������������������������������� 335 Albert L. Merati, Clark A. Rosen, and C. Blake Simpson 39 Botulinum  Toxin Injection of the Larynx����������������������������������������������������������������� 343 C. Blake Simpson, Lucian Sulica, and Clark A. Rosen 40 Awake  Superficial Vocal Fold Injection ������������������������������������������������������������������� 353 Daniel J. Cates, C. Blake Simpson, and Clark A. Rosen 41 Awake  Laser Treatment for Benign Laryngeal Pathology ������������������������������������� 359 Kathleen M. Tibbetts, C. Blake Simpson, and Clark A. Rosen 42 Awake  Treatment of Laryngotracheal Stenosis������������������������������������������������������� 373 Peter C. Belafsky, C. Blake Simpson, and Clark A. Rosen Part VI Laryngeal Framework Surgery 43 Principles  of Laryngeal Framework Surgery����������������������������������������������������������� 387 Lucian Sulica, Clark A. Rosen, and C. Blake Simpson 44 Perioperative  Care for Laryngeal Framework Surgery����������������������������������������� 393 Lucian Sulica, C. Blake Simpson, and Clark A. Rosen 45 Silastic  Medialization Laryngoplasty for Unilateral Vocal Fold Paralysis ����������� 399 C. Blake Simpson and Clark A. Rosen 46 GORE-TEX® Medialization Laryngoplasty������������������������������������������������������������� 415 Clark A. Rosen, C. Blake Simpson, and Gregory N. Postma 47 Arytenoid Adduction ������������������������������������������������������������������������������������������������� 423 C. Blake Simpson and Clark A. Rosen 48 Adduction Arytenopexy��������������������������������������������������������������������������������������������� 431 Adam M. Klein and Anju Patel 49 Cricothyroid Subluxation������������������������������������������������������������������������������������������� 437 C. Blake Simpson and Clark A. Rosen 50 Translaryngeal  Removal of Teflon Granuloma������������������������������������������������������� 441 C. Blake Simpson and Clark A. Rosen 51 Excision  of Combined Laryngocele��������������������������������������������������������������������������� 447 C. Blake Simpson and Clark A. Rosen

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52 Repair  of Laryngeal Fracture����������������������������������������������������������������������������������� 455 C. Blake Simpson and Clark A. Rosen 53 Selective  Laryngeal Adductor Denervation and Reinnervation����������������������������� 463 Dinesh K. Chhetri 54 Laryngeal  Reinnervation for Unilateral Vocal Fold Paralysis������������������������������� 471 Randal C. Paniello 55 Hypopharyngeal Pharyngoplasty ����������������������������������������������������������������������������� 479 Peak Woo and C. Blake Simpson 56 The  Gray Minithyrotomy for Vocal Fold Scar/Sulcus Deformity of the Vocal Fold��������������������������������������������������������������������������������������� 487 Lucian Sulica, C. Blake Simpson, and Clark A. Rosen Part VII Open Airway Reconstruction 57 Glottic  and Subglottic Stenosis: Laryngotracheal Reconstruction with Grafting��������������������������������������������������������������������������������������������������������������� 497 Gregory R. Dion, Milan R. Amin, and C. Blake Simpson 58 Cricotracheal  Resection with Primary Anastomosis����������������������������������������������� 511 Alessandro de Alarcón 59 Tracheal  Stenosis: Tracheal Resection with Primary Anastomosis����������������������� 519 Albert L. Merati and C. Blake Simpson 60 Slide Tracheoplasty����������������������������������������������������������������������������������������������������� 525 Alessandro de Alarcón Part VIII Miscellaneous Laryngeal Surgery 61 Wendler Glottoplasty for Transfeminine Voice ������������������������������������������������������� 533 Joseph Chang, Mark S. Courey, and Clark A. Rosen 62 Chondrolaryngoplasty ����������������������������������������������������������������������������������������������� 541 VyVy N. Young, Rahul Seth, and Clark A. Rosen 63 Awake  Posterior Pharyngeal Wall Augmentation for Velopharyngeal Insufficiency����������������������������������������������������������������������������������������������������������������� 549 VyVy N. Young and Clark A. Rosen 64 Upper  Cervical Esophageal Dilation������������������������������������������������������������������������� 553 Daniel J. Cates and Clark A. Rosen 65 Endoscopic  Surgery for Zenker Diverticulum��������������������������������������������������������� 559 Lyndsay Leigh Madden and Clark A. Rosen 66 Open  Surgery for Zenker Diverticulum������������������������������������������������������������������� 569 Christopher M. Johnson 67 Superior  Laryngeal Nerve Block for Chronic Cough��������������������������������������������� 577 Kathleen M. Tibbetts and C. Blake Simpson Index�����������������������������������������������������������������������������������������������������������������������������������  583

Contents

Contributors and Commentators

Contributors Alessandro  de Alarcón Department of Otolaryngology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA Milan  R.  Amin, MD Department of Otolaryngology—Head and Neck Surgery, NYU Langone Medical Center, New York, NY, USA Peter  C.  Belafsky, MD, MPH, PhD Department of Otolaryngology—Head and Neck Surgery, University of California, Davis, Sacramento, CA, USA Thomas L. Carroll, MD  Otolaryngology, Harvard Medical School, Brigham and Women’s Hospital, Boston, MA, USA Daniel  J.  Cates, MD  Otolaryngology—Head and Neck Surgery, University of California, Davis, Sacramento, CA, USA Joseph  Chang, MD  Division of Laryngology, Department of Otolaryngology - Head and Neck Surgery, University of Washington, Seattle, WA, USA Dinesh  K.  Chhetri, MD  Department of Voice, Airway, and Swallowing Disorders, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA Mark  S.  Courey, MD Department of Otolaryngology, Mount Sinai Health System, New York, NY, USA Gregory R. Dion  Dental and Craniofacial Trauma Research Department, U.S. Army Institute of Surgical Research, San Antonio, TX, USA Laura  Dominguez, MD Department of Otolaryngology, Cleveland Clinic Florida, Coral Springs, FL, USA Alexander  Gelbard, MD Department of Otolaryngology—Head and Neck Surgery, Vanderbilt University Medical Center, Nashville, TN, USA Michael  M.  Johns III, MD  Otolaryngology—Head and Neck Surgery, Keck Medicine of USC, Los Angeles, CA, USA Christopher  M.  Johnson, MD Medical College of Georgia, Augusta University Medical Center, Augusta, GA, USA Adam M. Klein, MD  Department of Otolaryngology, Emory University School of Medicine, Emory Voice Center, Atlanta, GA, USA Priya  Krishna, MD, MS  Loma Linda University Health System, Loma Linda University Voice and Swallowing Center, Loma Linda, CA, USA Lyndsay  Leigh  Madden, DO Department of Otolaryngology—Head and Neck Surgery, Wake Forest School of Medicine, Winston-Salem, NC, USA xxi

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Karen J. Maresch, DNAP, CRNA  Department of Anesthesiology, University of Pittsburgh Medical Center, Pittsburgh, PA, USA Patrick  O.  McGarey Jr, MD Department of Otolaryngology—Head and Neck Surgery, University of Virginia Health System, Charlottesville, VA, USA Albert L. Merati, MD  Department of Otolaryngology—Head and Neck Surgery, University of Washington Medical Center, Seattle, WA, USA Matthew R. Naunheim, MD, MBA  Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, MA, USA Randal C. Paniello, MD, PhD  Department of Otolaryngology, Washington University, St. Louis, MO, USA George  W.  Pasvankas, MD  Department of Anesthesiology and Perioperative Care, UCSF Pain Management Center, University of California San Francisco, San Francisco, CA, USA Gregory  N.  Postma, MD Center for Voice, Airway and Swallowing Disorders, Medical College of Georgia at Augusta University, Augusta, GA, USA Clark A. Rosen  UCSF Voice & Swallowing Center, Department of Otolaryngology-Head & Neck Surgery, University of California, San Francisco, San Francisco, CA, USA László  Rovó, MD, PhD  Department of Oto-Rhino-Laryngology and Head–Neck Surgery, University of Szeged, Szeged, Hungary Robert  Thayer  Sataloff, MD Department of Otolaryngology—Head and Neck Surgery, Drexel University College of Medicine, Philadelphia, PA, USA Rahul Seth, MD  UCSF Voice & Swallowing Center, Department of Otolaryngology-Head & Neck Surgery, University of California, San Francisco, San Francisco, CA, USA Hagit  Shoffel-Havakuk, MD Otolaryngology Head and Neck Surgery, Rabin Medical Center, Tel Aviv University, Petah Tikva, Israel C. Blake Simpson  Department of Otolaryngology—Head and Neck Surgery, University of Alabama at Birmingham, Birmingham, AL, USA Libby J. Smith, DO  Department of Otolaryngology, University of Pittsburgh Medical Center, Pittsburgh, PA, USA Phillip C. Song, MD  Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, MA, USA Lucian Sulica, MD  Department of Otolaryngology—Head and Neck Surgery, Weill Cornell Medical College, New York, NY, USA Kathleen  M.  Tibbetts, MD Department of Otolaryngology—Head and Neck Surgery, University of Texas Southwestern Medical Center, Dallas, Dallas, TX, USA Peak Woo, MD  Department of Otolaryngology, Icahn School of Medicine at Mount Sinai, New York, NY, USA Christopher  T.  Wootten, MD Vanderbilt Children’s Otolaryngology—Head and Neck Surgery, Nashville, TN, USA VyVy  N.  Young, MD  UCSF Voice & Swallowing Center, Department of OtolaryngologyHead & Neck Surgery, University of California, San Francisco, San Francisco, CA, USA Department of Otolaryngology—Head and Neck Surgery, University of California, Davis, Sacramento, CA, USA

Contributors and Commentators

Contributors and Commentators

xxiii

Contributing Commentators Lee M. Akst, MD  Department of Otolaryngology—Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA Milan  R.  Amin, MD Department of Otolaryngology—Head and Neck Surgery, NYU Langone Medical Center, New York, NY, USA Robert W. Bastian, MD  Bastian Voice Institute, Downers Grove, IL, USA Peter  C.  Belafsky, MD, MPH, PhD Department of Otolaryngology—Head and Neck Surgery, University of California, Davis, Sacramento, CA, USA Joel H. Blumin, MD, FACS  Department of Otolaryngology and Communication Sciences, Medical College of Wisconsin, Milwaukee, WI, USA Paul  C.  Bryson, MD, MBA  Otolaryngology—Head and Neck Surgery, Cleveland Clinic, Cleveland, OH, USA James  Burns, MD Otolaryngology—Head and Neck Surgery, Northwestern Memorial Hospital, Chicago, Illinois, USA Guillermo Campos, MD  Department of Surgery, Fundacion Santa Fe Hospital Universitario, Bogota, D.C., Colombia Mark  S.  Courey, MD Department of Otolaryngology, Mount Sinai Health System, New York, NY, USA Roger L. Crumley, MD  Department of Otolaryngology—Head and Neck Surgery, University of California Irvine, Orange, CA, USA Seth H. Daley, MD  Department of Surgery, University Hospital, Madison, WI, USA C. Gaelyn Garrett, MD  Department of Otolaryngology—Head and Neck Surgery, Vanderbilt University Medical Center, Nashville, TN, USA Norman D. Hogikyan, MD, FACS  Department of Otolaryngology—Head and Neck Surgery, University of Michigan, Ann Arbor, MI, USA Michael  M.  Johns III, MD  Otolaryngology—Head and Neck Surgery, Keck Medicine of USC, Los Angeles, CA, USA Adam M. Klein, MD  Department of Otolaryngology, Emory University School of Medicine, Emory Voice Center, Atlanta, GA, USA Luis Leopoldo Llamas, MD  Department of Anesthesiology and Pain Management, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA Robert Roman Lorenz, MD, MBA  Head and Neck Institute, Cleveland Clinic, Cleveland, OH, USA Ted Mau, MD, PhD  Department of Otolaryngology—Head and Neck Surgery, University of Texas Southwestern Medical Center, Dallas, TX, USA Andrew  J.  McWhorter, MD Department of Otolaryngology—Head and Neck Surgery, Louisiana State University Health Sciences Center—New Orleans, Baton Rouge, LA, USA Albert L. Merati, MD  Department of Otolaryngology—Head and Neck Surgery, University of Washington Medical Center, Seattle, WA, USA Randal C. Paniello, MD, PhD  Department of Otolaryngology, Washington University, St. Louis, MO, USA

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Gregory  N.  Postma, MD Center for Voice, Airway and Swallowing Disorders, Medical College of Georgia at Augusta University, Augusta, GA, USA Marc  Remacle, MD, PhD ORL and Head and Neck Surgery, Centre Hopitalier de Luxembourg, Luxembourg, Luxembourg David  E.  Rosow, MD, FACS  Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA Guri Sandhu, MBBS, MD, FRCS, FRCS (ORL-HUS)  Department of Ear, Nose and Throat, Imperial College NHS Trust, London, UK John  T.  Sinacori, MD, FACS Department of Otolaryngology, Eastern Virginia Medical School, Norfolk, VA, USA Lucian Sulica, MD  Department of Otolaryngology—Head and Neck Surgery, Weill Cornell Medical College, New York, NY, USA Mark  C.  Weissler, MD, FACS  Department of Otolaryngology—Head and Neck Surgery, University of North Carolina, Chapel Hill, Chapel Hill, NC, USA Peak Woo, MD  Department of Otolaryngology, Icahn School of Medicine at Mount Sinai, New York, NY, USA

Contributors and Commentators

Part I Clinical Evaluation of Laryngeal Disorders

1

Anatomy and Physiology of the Larynx Hagit Shoffel-Havakuk and Michael M. Johns III

1.1

Anatomy

1.1.1

Laryngeal Cartilages

1.1.1.1 Thyroid Cartilage The laryngeal skeleton consists of several cartilaginous structures (Fig. 1.1), the largest of which is the thyroid cartilage. The thyroid cartilage is composed of two rectangular laminae that are anteriorly fused in the midline. The incomplete fusion of the two laminae superiorly forms the thyroid notch. The thyroid cartilage’s interlaminar angle ranges between 63° and 90° in men and 80° and 120° in women. Attached to each lamina posteriorly are the superior and inferior cornua. The superior cornua articulate with the greater horns of the hyoid bone, whereas the inferior cornua form a synovial joint with the cricoid cartilage (the cricothyroid joint). At the junction of each superior cornu, with its respective thyroid ala, is a cartilaginous prominence, the superior tubercle. The superior tubercle is of significance because it marks the point 1  cm below which the superior laryngeal artery and nerve cross over the lamina laterally to pierce the thyrohyoid membrane. The sternothyroid and the thyrohyoid strap muscles attach to the anterior surface of the thyroid laminae at the oblique line. The inferior pharyngeal constrictor muscles insert on the posterior edge of each thyroid lamina. The relationship of the internal laryngeal structures with the surface anatomy of the thyroid cartilage is important in surgical planning, particularly when planning the placement of the window for thyroplasty. The level of the vocal fold lies closer to the lower border of the thyroid cartilage lamina than to the upper and not at its midpoint, as is frequently (and H. Shoffel-Havakuk Department of Otolarynology Head and Neck Surgery, Rabin Medical Center, Tel Aviv University, Petah Tikva, Israel M. M. JohnsIII (*) Department of Otolaryngology—Head and Neck Surgery, Keck Medicine of USC, Los Angeles, CA, USA e-mail: [email protected]

Fig. 1.1 Cartilaginous and fibroelastic structures of the larynx

erroneously) stated. Correct placement of the window is necessary to avoid medialization of the false vocal folds or ventricular mucosa.

1.1.1.2 Cricoid Cartilage This signet ring-shaped cartilage is the only laryngeal cartilage to completely encircle the airway. The cricoid cartilage articulates with the thyroid cartilage’s inferior cornua on the cricothyroid joint facets. It joins the first tracheal ring inferiorly via membranous attachments. The face of the cricoid cartilage has a vertical height of only about 3–4 mm, whereas the lamina posteriorly stands at about 20–30 mm high. There is a steep incline from the anterior to the posterior of the

© Springer Nature Switzerland AG 2024 C. A. Rosen, C. B. Simpson, Operative Techniques in Laryngology, https://doi.org/10.1007/978-3-031-34354-4_1

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superior margin of the cricoid cartilage. This incline leaves an anterior window where the cricothyroid membrane lies.

1.1.1.3 Arytenoid Cartilage The arytenoid cartilages are paired, pyramidal cartilages that articulate with the posterior lamina of the cricoid cartilage at the cricoarytenoid joint. Each arytenoid has both a vocal process medially and a muscular process laterally. These processes act as the attachment sites for the vocal ligament and the major intrinsic muscles of vocal fold movement, respectively. 1.1.1.4 Accessory Cartilages: Cuneiform and Corniculate The cuneiform cartilages are the cricoarytenoid joint’s paired elastic cartilages that sit on top of, and move with, the corresponding arytenoid. The soft tissue of the aryepiglottic folds covers these cartilages. The corniculates are small, paired, fibroelastic cartilages that sit laterally to each of the arytenoids and are completely embedded within the aryepiglottic folds. These likely provide additional structural support to the aryepiglottic folds. 1.1.1.5 Epiglottis The epiglottis is an oblong, feather-shaped fibroelastic cartilage that is attached, at its inferior end (the petiole), to the inner surface of the thyroid cartilage laminae just above the anterior commissure. The cartilage of the epiglottis contains multiple small fenestrations. The major function of the epiglottis is to help prevent aspiration during swallowing. The epiglottis is posteriorly displaced by tongue base contraction and laryngeal elevation. This causes the superior free edge of the epiglottis to fall over the laryngeal inlet, which, in conjunction with the sphincteric closure of the larynx at the glottic and supraglottic levels, closes off the laryngeal vestibule. The epiglottis can be divided into suprahyoid and infrahyoid parts, by the horizontal plane that passes through the hyoid bone. The infrahyoid epiglottis communicates anteriorly with the pre-epiglottic space (PES), which provides a pathway for tumor spread. The PES contains fat and areolar tissue. It is posteriorly bounded by the epiglottis and the thyroepiglottic ligament, superiorly by the hyoid bone, the hyoepiglottic ligament, and the vallecula, and anteriorly by the thyroid cartilage and the thyrohyoid membrane. The PES communicates with the paraglottic space (PGS) on each side.

1.1.2 Laryngeal Joints 1.1.2.1 Cricothyroid Joint The cricothyroid joint is a synovial joint formed from the articulation of the inferior cornu of the thyroid cartilage bilaterally with facets on the cricoid lamina. The two major actions

H. Shoffel-Havakuk and M. M. Johns

at this joint are anteroposterior sliding and rotation of the inferior thyroid cornu upon the cricoid cartilage. Cricothyroid muscle contraction pulls the thyroid ala anteriorly with respect to the cricoid cartilage and closes the anterior visor angle between the thyroid and the cricoid cartilage. This motion increases the distance between the anterior commissure and the vocal processes and serves to lengthen and tense the vocal folds. This joint can be manipulated to assist in pitch control in cases of paralytic dysphonia. Cricothyroid joint subluxation, resulting in an exaggerated decrease in the anterior cricothyroid angle, can assist in traditional medialization procedures to provide vocal fold tightening.

1.1.2.2 Cricoarytenoid Joint The cricoarytenoid joint is the primary moving structure of the intrinsic larynx (Fig. 1.2). The arytenoids articulate with the cricoid cartilage and form multiaxial joints. The action of movement at the cricoarytenoid joints changes the distance between the vocal processes of the two arytenoids and between each vocal process and the anterior commissure. The combined action of the intrinsic laryngeal muscles on the arytenoid cartilages alters the position and shape of the vocal folds. Each cricoarytenoid joint sits at a surprisingly steep 45° angle with the horizontal plane on the cricoid cartilage and permits motion in a sliding, rocking, and twisting manner.

1.1.3 Laryngeal Musculature 1.1.3.1 Intrinsic Laryngeal Muscles The intrinsic muscles of the larynx are responsible for altering the length, tension, shape, and spatial position of the vocal folds by changing the orientation of the muscular and vocal processes of the arytenoids with the fixed anterior commissure (Fig. 1.3). Traditionally, the muscles are categorized into the following scheme: three major vocal fold adductors, one abductor, and one tensor muscle. Adductor Muscles of the Larynx Lateral Cricoarytenoid (LCA) Muscle

This paired laryngeal muscle is attached to the anterior part of the muscular process medially and to the superior border of the cricoid cartilage laterally. Contraction of this muscle results in movement of the muscular process anterolaterally while simultaneously forcing the vocal process downward and medially. The result is adduction and lengthening of the vocal folds. This muscle runs lateral and, in large part, is parallel to the thyroarytenoid (TA) muscle. Thyroarytenoid (TA) Muscle

The thyroarytenoid muscle consists of two main muscle bellies, the internus and the externus. The thyroarytenoid exter-

1  Anatomy and Physiology of the Larynx

5

Fig. 1.2  Cricoarytenoid joint action in abduction (left) and adduction (right). The lowering of the vocal process as adduction occurs should be noted

Fig. 1.3 Neuromuscular structures of the larynx

nus inserts anteriorly at the anterior commissure (Broyles’ ligament) and posterolaterally on the lateral surface of the arytenoid. During contraction of this portion of the muscle, the vocal process is brought closer to the anterior commissure and the vocal folds are shortened and adducted. The thyroaryte-

noid internus arises from the anterior commissure and inserts onto the vocal process of the arytenoid cartilage. During contraction, the vocal folds are shortened and thickened. This portion of the thyroarytenoid is also known as the vocalis muscle. In isolation, this action serves to lower the resonant frequency

6

of the vocal folds. In most cases, there is a significant superior extension of the TA muscle into the false vocal folds, often referred to as the ventricularis muscle. Interarytenoid (IA) Muscle

This non-paired muscle consists of both transverse and oblique fibers. The transverse fibers insert on the posterior face of each arytenoid and run horizontally, whereas the oblique fibers attach to each arytenoid apex and run obliquely to attach to the posterior face on the opposite side. Contraction of this muscle leads to arytenoid adduction, closure of the posterior glottis, and narrowing of the laryngeal inlet. Some oblique fibers extend to travel along the quadrangular membrane and are referred to as the aryepiglottic muscle. This muscle receives bilateral innervation. Abductor Muscle Posterior Cricoarytenoid (PCA) Muscle

The posterior cricoarytenoid muscle arises from the posterior face of the cricoid lamina. Its fibers run diagonally to insert on the muscular process of the arytenoid. Contraction displaces the muscular process posteriorly and caudally, whereas the vocal process moves upward and laterally. The result is vocal fold abduction. The posterior cricoarytenoid muscle is the only abductor of the vocal folds and is principally responsible for control of the glottic airway. The posterior cricoarytenoid muscle affects motion at the cricoarytenoid joint in two planes by its two separate muscle bellies. The medial portion of the posterior cricoarytenoid muscle (the horizontal belly) arises from the posterior cricoid lamina and courses obliquely in a superolateral manner to insert on the medial aspect of the muscular process. The lateral portion of the PCA muscle (the vertical belly) runs in a more vertical manner to insert on the lateral side of the muscular process. Because of slightly different positions and orientations, contraction of each muscle belly in isolation causes cricoarytenoid joint motion about a different oblique axis. The horizontal belly of the PCA muscle has been shown, in cadaver studies, to cause motion in a more vertical axis (true vocal fold abduction), whereas the vertical belly keeps the arytenoids “upright” and has a major role in vocal fold length and tension. The PCA muscle anatomy serves as a key landmark for arytenoid adduction surgery. Tensor Muscle Cricothyroid Muscle

The cricothyroid muscle is a laryngeal tensor, composed of two separate muscle bellies, located on the external surface of the laryngeal cartilages. The pars recta, the more vertical component, arises laterally from the superior rim of the cricoid cartilage and inserts on the inferior rim of the thyroid cartilage, whereas the pars obliqua runs obliquely from the superior arch of the cricoid to insert on the inferior cornu. Contraction of the cricothyroid muscle bellies affects motion

H. Shoffel-Havakuk and M. M. Johns

at the cricothyroid joint. During contraction, the cricothyroid space is narrowed anteriorly, whereas the posterior cricoid lamina and cricoarytenoid joints are forced caudally, resulting in lengthening, tightening, and thinning of the vocal folds and in increasing their resonant frequency. This action also results in vocal fold adduction.

1.1.3.2 Extrinsic Laryngeal Muscles The infrahyoid muscles, also known as strap muscles (the sternothyroid, sternohyoid, omohyoid, and thyrohyoid), as well as the mylohyoid, digastric, geniohyoid, and stylopharyngeus muscles all act in concert to provide laryngeal stabilization and play a major role in swallowing.

1.1.4 Fibroelastic Tissue of the Larynx 1.1.4.1 Quadrangular Membrane The quadrangular membrane is an accessory elastic support structure of the supraglottic larynx. It attaches anteriorly to the lateral edges of the epiglottis and wraps around posteriorly to attach to the arytenoids. The superior free edge of the quadrangular membrane is the mucosa-covered aryepiglottic fold. As the quadrangular membrane extends inferiorly, it becomes the medial wall of the piriform sinus. At its inferior extent, it is continuous with the vestibular ligament. 1.1.4.2 Conus Elasticus The thick fibroelastic support structure of the glottis and subglottis originates inferiorly along the superior border of the cricoid cartilage. It extends superiorly to attach to the anterior commissure and vocal processes. The conus elasticus rolls medially within the substance of the vocal fold; its medial extent is the vocal ligament. Anteriorly, the conus elasticus is continuous with the cricothyroid membrane.

1.1.5 Endolaryngeal Structures The division of the larynx into three regions, namely, the supraglottis, glottis, and subglottis, reflects the embryological origin, vasculature, lymphatics, and innervation. The glottis is composed of the superior and inferior surfaces of the true vocal folds. The superior border of the glottis, which separates it from the supraglottis, is the horizontal plane passing through the lateral margin of the ventricles. The estimated location of the inferior border of the glottis is 1 cm below this horizontal plane. While the true vocal folds are covered with the stratified squamous epithelium, the epithelium of the supraglottis and the subglottis is predominantly respiratory (ciliated pseudostratified columnar, enriched with goblet cells). The submucosa of the respiratory epithelium contains mixed mucous and serous glands. Specific

1  Anatomy and Physiology of the Larynx

regions of the supraglottis such as the edges of the aryepiglottic folds and the lateral borders of the epiglottis are covered with the stratified squamous epithelium. The histological transitions from the respiratory to the stratified squamous epithelium above and below the vocal folds are described as the superior and inferior arcuate lines, respectively. The laryngeal ventricles are the fossae that lie between each vocal fold and the ipsilateral vestibular fold. A saccule is an anterior–superior extension of the ventricle, and its function in humans is vocal fold lubrication. On either side of the endolarynx is the paraglottic space. The paraglottic space originates superiorly within the aryepiglottic fold. Continuing inferiorly, the medial borders of the paraglottic space are the quadrangular membrane, the ventricle, and the conus elasticus until it attaches the cricoid. Posterior to the paraglottic space is the piriform sinus. It is anteriorly bordered by the thyroid cartilage and communicates with the PES.

1.1.5.1 Microanatomy of the Vocal Folds The complex microanatomy of the true vocal fold allows the loose and pliable superficial mucosal layers to vibrate freely over the stiffer structural underlayers (Fig.  1.4). The true vocal fold can be divided into three major layers: the mucosa, the vocal ligament, and the underlying muscle. The mucosa of the vocal fold is highly specialized for its vibratory function; it can also be divided into layers. The most superficial layer is the stratified squamous epithelium. Deep to the epithelium are three layers of the lamina propria, each of increasing rigidity. The most superficial layer (superficial layer of the lamina propria or SLP) is mostly acellular and composed of extracellular matrix proteins, water, and loosely arranged fibers of collagen and elastin. The SLP is gelatinous in nature. Hyaluronic acid, as one of the glycosaminoglycans, significantly contributes to the tissue’s viscosity and

Fig. 1.4  The coronal section through the free edge of the vocal fold, demonstrating the layered microanatomical structures that allow vibration

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viscoelasticity. The potential space between the SLP and the intermediate layer of the lamina propria is Reinke’s space. The intermediate and deep layers of the lamina propria (ILP and DLP, respectively) are mostly composed of elastin and collagen. The collagen fibers (predominantly types I and III) of the lamina propria are arranged in an intertwined network; this allows the vocal folds to stretch, even though they contain non-stretchable fibers. The deepest and most dense layer (DLP) is composed of tightly arranged collagen fibers; these fibers penetrate the muscle and surround the muscle bundles. In all the layers, the lamina propria, glycosaminoglycans, and glycoproteins occupy the spaces between the reticular and elastic fibers. The ILP and DLP together form the vocal ligament. The gelatinous superficial layer of the lamina propria, together with the squamous epithelium, moves freely over the underlying vocal ligament and muscle to form the vibrations that produce sound. The maculae flavae are dense masses, located at the anterior and posterior ends of the membranous vocal folds. The vocal fold stellate cells within the maculae flavae differ from other fibroblasts morphologically and functionally. They are assumed to be responsible for the production of extracellular matrix components, for the development of the vocal ligament, and for maintaining the layered structure of the vocal fold’s lamina propria. The vocal fold mucosa and vocal ligament cover the vocalis muscle and extend from the anterior commissure to the vocal processes of the arytenoids. The mucosa and vocal ligament extend posteriorly to cover the entirety of the vocal process. The posterior third of the true vocal fold, is the respiratory or the cartilaginous portion of the vocal fold, whereas the anterior two-thirds of the vocal fold is the phonatory or the membranous portion of the vocal fold.

1.1.6 Vasculature of the Larynx The arterial supply to the larynx comes from the superior and inferior laryngeal arteries; the venous supply mirrors the arterial supply. The superior laryngeal artery is a branch of the superior thyroid artery, which arises directly from the external carotid. The superior laryngeal artery branches from the superior thyroid artery at the level of the hyoid bone. This artery then courses medially with the internal branch of the superior laryngeal nerve (SLN) and enters the thyrohyoid membrane 1 cm anterior and superior to the superior tubercle. The cricothyroid artery, one of the major branches of the superior laryngeal artery, runs along the inferior surface of the thyroid cartilage to supply its similarly named muscle and joint. Branches of this artery pierce the cricothyroid membrane and ascend on the internal surface of the thyroid cartilage, making them possible targets during the creation of a thyroplasty window. The second major arterial supply to the larynx comes from the inferior laryngeal artery, a branch

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of the inferior thyroid artery. This artery enters the larynx between fibers of the inferior constrictor muscle and anastomoses with the branches of the superior laryngeal artery.

1.1.7 Innervation of the Larynx Corticobulbar fibers from the cerebral cortex descend through the internal capsule and synapse on the motor neurons in the nucleus ambiguus, the area within the brainstem (medulla) from which the fibers contributing to the vagus nerve arise. Lower motor neurons leave the nucleus ambiguus and travel laterally, exiting the medulla between the olive and the pyramid as a series of 8–10 rootlets. These rootlets coalesce into a single nerve root, known as the vagus nerve, which then exits the skull base via the jugular foramen. The vagus nerve descends in the carotid sheath, giving off three major branches: the pharyngeal branch, the superior laryngeal nerve (SLN), and the recurrent laryngeal nerve (RLN). The SLN branches from the vagus nerve close to the inferior part of the nodose ganglion and about 4 cm above the carotid bifurcation. As it travels caudally, it divides into internal and external branches. Approximately 2–4  mm inferior to the greater cornu of the hyoid bone, the internal branch travels medially to pierce the thyrohyoid membrane and provide sensation to the glottic and supraglottic larynx. These anatomical landmarks indicate the location for SLN block (see Chapter 67—“Superior Laryngeal Nerve Block for Chronic Cough”). The external branch carries motor input to the cricothyroid muscle, which controls vocal fold lengthening and pitch. There are some recent anatomical studies that have suggested that the superior aspect of the TA muscle (the ventricularis muscle in the false vocal fold) may have SLN innervation, which could explain the presence of false vocal fold muscular contraction in cases of RLN transection. The RLN arises from the vagus nerve in the upper chest and loops under the aortic arch (left) or subclavian artery (right) and ascends back into the neck, traveling in the tracheoesophageal groove. The nerve enters the larynx posteriorly, adjacent to the cricothyroid joint (Fig.  1.3). Although there are variations in the RLN branching, there are several reliable patterns. The first motor branch, which emerges as the RLN, enters the larynx at the cricothyroid articulation and carries motor fibers to the posterior cricoarytenoid (PCA) muscle. It then often extends toward the midline to supply motor fibers to the interarytenoid (IA) muscle (an unpaired muscle). The IA muscle receives a separate branch from each RLN, resulting in bilateral innervation. The terminal branches of the RLN innervate the lateral cricoarytenoid (LCA) and

H. Shoffel-Havakuk and M. M. Johns

thyroarytenoid (TA) muscles. Thus, the RLN supplies all of the intrinsic laryngeal muscles with the exception of the cricothyroid muscle (and possibly the ventricularis muscle, as indicated above). Ipsilateral RLN transection typically results in vocal fold immobility (the ipsilateral crico-thyroid muscle does not contribute to vocal fold adduction or abduction). It is important to remember, however, that the interarytenoid muscle is unpaired and that contralateral RLN input to the IA may lead to some adduction of the vocal fold on the paralyzed side. The RLN also supplies the glottic and subglottic mucosa and the myotatic receptors of the laryngeal musculature. There are several known anastomoses between the SLN and RLN; the most studied one is Galen’s anastomosis, located over the dorsal PCA and can be found in most people. It gives off sensory branches to the pharyngeal mucosa and may also give off motor fibers to the PCA muscle. Other possible anastomoses of the SLN with the RLN may provide motor fibers to the TA or LCA muscles. The human communicating nerve arises from the external superior laryngeal nerve and pierces the cricothyroid membrane to provide innervation to the internal contents of the larynx.

1.2 Physiology 1.2.1 Major Laryngeal Functions: Airway Protection, Respiration, and Phonation The most primitive of the laryngeal functions is protection of the airways. In humans, the larynx has evolved into a highly complex and specialized organ not only for airway protection and control of respiration but also for sound and speech production. Precise control of all of these mechanisms, as well as the exact anatomical structure, is required for normal laryngeal functioning. The larynx has evolved several important reflexes for the purpose of airway protection against external stimuli and foreign bodies. These reflex mechanisms are relayed by the mucosal (sensory afferent), myotatic, and articular receptors of the larynx via both the superior and recurrent laryngeal nerves (Fig. 1.3). The strongest of the laryngeal reflexes is that of laryngospasm—a response to mechanical stimulation. The larynx has also evolved reflexes that produce cough, apnea, bradycardia, and hypotension.

1.2.1.1 Phonation The most complex and highly specialized of the laryngeal functions is sound production. The ability to couple phona-

1  Anatomy and Physiology of the Larynx

tion with articulation and resonance allows for human speech. Phonation and precisely how it relates to laryngeal vibration has undergone many evolving theories over the years. Sound production requires that several mechanical properties be met. There must be adequate breath support to produce sufficient subglottic pressure. There must also be adequate control of the laryngeal musculature to produce not only glottic closure but also the proper length and tension of the vocal folds. Finally, there must be favorable pliability and vibratory capacity of the tissues of the vocal folds. Once these conditions are met, sound is generated from vocal fold vibration. The detailed contribution, timing, and recruitment of each of the above-described laryngeal muscles in the production of sound have been studied. In a fine-wire electromyographic study of human larynges, it was found that the intrinsic laryngeal muscles are not only highly specialized for their particular vector of action but are also controlled for the timing of the onset of contraction and the degree of recruitment and fade during phonation. The thyroarytenoid and the lateral cricoarytenoid muscles have been shown to exhibit burst-like activity at the onset of phonation (as well as ­pre-­phonatory), with a measurable degree of fade during sustained phonation. The interarytenoid muscle, on the other hand, has been shown to have increased latency of contraction but regular sustained tonicity during prolonged sound production. The cricothyroid seems to exhibit the greatest measurable action with increases in pitch and volume, whereas the posterior cricoarytenoid shows its greatest degree of activation with voluntary deep inhalation and sniff functions. Actual phonation is a complex and specialized process that involves not only brainstem reflexes and the muscular actions described above but also high-level cortical control. Accessory effects such as lung capacity, chest wall compliance, pharyngeal, nasal, and oral anatomy, and subsequent mental status also play a role. The process begins with inhalation and subsequent glottal closure. An increase in subglottic pressure follows until the pressure overcomes the glottal closure force and air is allowed to escape between the vocal folds. Once air passes between the vocal folds, the body-­cover concept of phonation takes effect. The body-cover theory describes the wave-like motion of the loose mucosa of the vocal folds over the stiffer, more densely organized vocal ligament and vocalis muscle. This motion is known as the mucosal wave. The wave begins infraglottically and is propagated upward to the free edge

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Fig. 1.5  A schematic of the coronal section through the vocal folds, demonstrating mucosal wave propagation. (1) Vocal folds are completely closed as subglottal pressure (arrow) builds up. (2) Lower lips separate due to rising subglottal pressure. (3) Only the upper lips are in contact. (4) A puff of air is released as the vocal folds separate completely. (5 and 6) As airflow continues, the elastic recoil of the vocal folds, as well as Bernoulli’s forces, result in the lower lips of the vocal folds drawing inward. At the same time, the mucosal wave is superolaterally propagated. (7) Airflow is reduced, and the lower lips are completely approximated. (8) In a zipper-like closure, the free edge of the vocal folds come into contact inferiorly to superiorly

of the vocal fold and then laterally over the superior surface (Fig. 1.5). Eventually, the inferior edges become reapproximated due to both a drop in pressure at the open glottis and the elastic recoil of the tissues themselves. The closure phase is also rostrally propagated. With the vocal folds fully approximated, subglottic pressure may again build and the cycle is repeated (Fig. 1.5).

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Key Points • The relationship of the surface anatomy of the thyroid and arytenoid cartilages with the internal laryngeal structures is critical to surgical planning for laryngeal framework surgery and in-office procedures (i.e., percutaneous laryngeal injections). • The primary adductor muscles of the larynx consist of –– The lateral cricoarytenoid (LCA) –– The thyroarytenoid (TA) –– The interarytenoid (IA) • The main abductor muscle of the larynx is the posterior cricoarytenoid (PCA). • The cricothyroid and the TA/LCA muscles control vocal fold length, tension, and vocal frequency. • The microanatomy of the vocal folds is complex and consists of the following layers, from superficial to deep: –– The epithelium –– The superficial lamina propria –– The intermediate lamina propria –– The deep lamina propria –– The vocalis muscle According to the body-cover theory, the cover (vibrating tissue) comprises the first two layers and the body comprises the last two layers. • Reinke’s space is a potential space between the superficial and intermediate layers of the lamina propria. The intermediate and deep layers of the lamina propria together are referred to as the vocal ligament.

Bibliography Armstrong WB, Netterville JL.  Anatomy of the larynx, trachea, and bronchi. Otolaryngol Clin N Am. 1995;28:685.

H. Shoffel-Havakuk and M. M. Johns Bielamowicza S.  Perspectives on medialization laryngoplasty. Otolaryngol Clin N Am. 2004;37:139–60. Bryant NJ, et  al. Human posterior cricoarytenoid muscle compartments: anatomy and mechanics. Arch Otolaryngol. 1996;122:1331. Buchthal F, Faaborg-Anderson K. Electromyography of laryngeal and respiratory muscles: correlation with respiration and phonation. Ann Otol Rhinol Laryngol. 1964;73:118. Gay T, et al. Electromyography of intrinsic laryngeal muscles during phonation. Ann Otol Rhinol Laryngol. 1972;181:401. Hillel A. The study of laryngeal muscle activity in normal human subjects and in patients with laryngeal dystonia using multiple fine– wire electromyography. Laryngoscope. 2001;111:1–47. Hirano M.  Structure and vibratory behavior of the vocal fold. In: Sawashima M, Cooper F, editors. Dynamic aspects of speech production. Tokyo: University of Tokyo; 1977. p. 13–30. Hirano M, Kakita Y. Cover-body theory of vocal fold vibration. Speech science. San Diego, CA: College-Hill Press; 1985. Jones-Bryant N, Woodsen GE, Kaufman K, et al. Human posterior cricoarytenoid muscle compartments: anatomy and mechanics. Arch Otolaryngol Head Neck Surg. 1996;122:1331–6. Kempster GB, Larson CR, Distler MK. Effects of electrical stimulation of cricothyroid and thyroarytenoid muscles on voice fundamental frequency. J Voice. 1988;2:221. Kotby MN, Kirchner JA, Kahane JC, Basiouny SE, El-Samaa M. Histo-­ anatomical structure of the human laryngeal ventricle. Acta Otolaryngol. 1991;111:396–402. Ludlow C. Recent advances in laryngeal sensorimotor control for voice, speech, and swallowing. Curr Opin Otolaryngol. 2004;12:160–5. Mathew OP, Abu-Osba YK, Thach BT. Influence of upper airway pressure changes in respiratory frequency. Respir Physiol. 1982;29:223. Platzer W.  Atlas of topographic and applied human anatomy: head and neck. In: Pernkopf anatomy, vol. 1. 3rd ed. Vienna: Urban & Schwarzenberg; 1989. Sanudo JR, Maranillo E, Leon X, et al. An anatomical study of anastomoses between the laryngeal nerves. Laryngoscope. 1999;109:983–7. Schwenzer V, Dorfl J. The anatomy of the inferior laryngeal nerve. Clin Otolaryngol Allied Sci. 1997;22:362–9. Zeitels SM. New procedures for paralytic dysphonia: adduction arytenopexy, Gortex medialization laryngoplasty, and cricothyroid subluxation. Otolaryngol Clin N Am. 2000;33:841–54.

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Principles of Clinical Evaluation for Voice Disorders Phillip C. Song and VyVy N. Young

2.1

Fundamental and Related Chapters

Please see Chapter 1—“Anatomy and Physiology of the Larynx”, Chapter 3—“Videostroboscopy and Dynamic Voice Evaluation with Flexible Laryngoscopy”, Chapter 4—“Pathological Conditions of the Vocal Fold”, and Chapter 5—“Glottic Insufficiency: Vocal Fold Paralysis, Paresis, and Atrophy” for further information.

2.2

Introduction

Many processes resulting in dysphonia affect the vocal folds in subtle ways. Objective evidence of vocal pathology is not always easily discernable on physical examination, even when aided by sophisticated diagnostic instruments. It is, therefore, essential that the laryngological exam be supported by a careful review of the patient’s medical and vocal history. Perhaps more than any other aspect of otolaryngology, the information derived from a careful review of the patient’s complaints provides an invaluable context within which to interpret the findings of the physical exam and objective voice testing.

2.3

Gathering a Patient’s History

A detailed and directed questionnaire mailed to patients before their office visits can have multiple advantages. First, it enables patients to accurately record the symptoms they are experiencing and to chronicle the history of their probP. C. Song (*) Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, MA, USA e-mail: [email protected] V. N. Young UCSF Voice & Swallowing Center, Department of Otolaryngology-Head & Neck Surgery, University of California, San Francisco, San Francisco, CA, USA e-mail: [email protected]

lems. It also allows them to comprehensively and accurately document all their medications and dosages. Addresses and telephone numbers of primary care and referring physicians can also be obtained. This strategy not only increases the efficiency of an office consultation but may also allow preliminary differential diagnosis to be formulated in certain patients. Standardized, patient-based, voice-related qualityof-life instruments should also be given to the patient prior to patient evaluation (see Sect. 2.9). Although useful, the questionnaire cannot substitute for a thoughtful and thorough face-to-face interview with the patient. The classic template of history of the present illness, past medical history, past surgical history, review of systems, medications, and social history provides a reliable framework for achieving a thorough medical and voice history.

2.4

History of Present Illness

The exact nature of the voice disorder patient’s chief complaint should be reviewed with care. The term hoarseness, for instance, is often used to describe a variety of symptoms, including loss of upper register, roughness, pitch instability, difficulty in transition between singing registers, breathiness, strain, increased vocal effort, and early vocal fatigue. Each of these symptoms can have distinct implications. A rough voice is often associated with abnormalities of the free edge of the vocal fold, as seen in laryngitis or mass lesions. Breathiness, on the other hand, results from any condition preventing full approximation of the vocal folds, leading to excessive loss of air during vocalization. Conditions that may cause breathiness include vocal fold paralysis/paresis, ankylosis of the cricoarytenoid joint, arytenoid dislocation, vocal fold scar, vocal fold lesions, and vocal fold atrophy. Raspiness refers to a disruption of the vocal harmony that usually reflects perturbation of the normal mucosal wave, resulting in instability of the fundamental frequency. A strained voice is often the result of hyperfunctional glottal closure. Although primary glottal hyperfunction may be the result of neurological impairment or poor vocal

© Springer Nature Switzerland AG 2024 C. A. Rosen, C. B. Simpson, Operative Techniques in Laryngology, https://doi.org/10.1007/978-3-031-34354-4_2

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technique, this hyperfunction may also represent a supraglottic compensation for glottal insufficiency. Early vocal fatigue can similarly result from glottal incompetence secondary to vocal fold atrophy, vocal fold scar, vocal fold lesions, or paresis. Inadequate airflow production from the lungs due to pulmonary or neuromuscular pathologies or generalized weakness and deconditioning can also present with vocal fatigue and/or decreased volume. Determining the duration of each voice complaint will distinguish acute processes from chronic dysfunction. An acute process, such as an upper respiratory infection (URI), for instance, may unmask or exacerbate a separate and potentially more consequential chronic process such as a vocal lesion or a pattern of vocal misuse. In addition, upper respiratory infection (URI) symptoms frequently precede the onset of a viral vagal neuropathy. Careful attention to the duration of each patient’s symptoms will thereby allow a complex symptom picture to be segregated into its component pathologies. The exact time course of the ailment can be particularly helpful in the evaluation of rapid-onset dysphonia. Sudden development of hoarseness (occurring over seconds or minutes) should, in fact, always raise suspicion of vocal fold hemorrhage or psychogenic etiologies. The social and occupational impact relative to voice complaints is a unique and important component of the laryngeal history. A voice history should include details on specific situational communication problems as well as the impact on occupation including economic changes. The social and emotional problems associated with communication difficulties are also important to detail, and quality-of-life questionnaires can be a valuable component of the history.

2.5 Past Medical History

P. C. Song and V. N. Young

cough, sore throat, halitosis, and, occasionally, dysphagia. A frequent complaint of patients with LPR is morning hoarseness that improves as the day progresses. This pattern is not seen in most other conditions causing dysphonia. Surprisingly, most patients with LPR do not present with heartburn, indigestion, or belching—the cardinal symptoms of gastroesophageal reflux disease. Consequently, LPR is often referred to as silent reflux. The pervasive but often overlooked nature of LPR demands that the physician evaluating the dysphonic patient consider this diagnosis in almost every case. The Reflux Symptom Index (RSI) is a nineitem, patient-based outcome instrument that is useful in predicting the likelihood of LPR (Table 2.1) It is easily administered and reproducible althought it should be recognized as potentially nonspecific and is best thought of a way to quantify patient’s “throat” symptoms and not as a diagnostic tool for LPR. Some degree of reflux is present in normal individuals, and an RSI of greater than 10 is considered abnormal. Endocrinological changes can have profound effects on the voice. Many of these changes are reflected in alterations of the lamina propria. An increase in acid mucopolysaccharides in the submucosal tissues of the vocal fold has been demonstrated in an animal model of induced hypothyroidism. This increase draws fluid into Reinke’s space osmotically, resulting in edema. The patient may complain of dysphonia, vocal fatigue, muffling of the voice, loss of range, and globus. Some women report vocal changes associated with the normal menstrual cycle. Most of the adverse effects occur in the premenstrual phase, a phenomenon known as laryngopathia premenstrualis. Slight hoarseness and muffling, vocal fatigue, and loss of the highest notes in the voice characterize this vocal dysfunction. Although relatively uncommon in women without formal vocal training, as many as a third of singers report menstrual dysphonia. In addition, vocal fold varices often increase in size before and during menstruation and have been associated with an increased incidence of submucosal vocal fold hemorrhages. A few important generalized neurological disorders are characterized by specific patterns of dysphonia. Neurological

Salient points regarding the patient’s history include any condition or medications potentially affecting the pulmonary status, posture, and hydration. Chronic obstructive pulmonary disease (COPD) will adversely affect the power supply for the patient’s voice. Various rheumatological and muscuTable 2.1  The Reflux Symptom Index loskeletal ailments can alter posture, impairing voice quality. 0 = No problem Any underlying acute or chronic inflammatory conditions Within the last month, how did the following problems affect you? 5 = Severe problem can significantly affect the voice. An allergic disease mani1. Hoarseness or a problem with your voice 0 1 2 3 4 5 festing as persistent postnasal drip, for instance, may lead to 2. Clearing your throat 0 1 2 3 4 5 chronic laryngeal inflammation and vocal fold irritation. 3. Excess throat mucus or postnasal drip 0 1 2 3 4 5 Anticholinergic effects of prescription, as well as over-the-­ 4. Difficulty swallowing food, liquids, or pills 0 1 2 3 4 5 counter medications, can affect mucosal hydration and lubri- 5. Coughing after you ate or after lying down 0 1 2 3 4 5 6. Breathing difficulties or choking episodes 0 1 2 3 4 5 cation and have an adverse effect on vocal fold vibration. 0 1 2 3 4 5 It has been estimated that approximately half of the patients 7. Troublesome or annoying cough 8. S  ensations of something sticking in your 0 1 2 3 4 5 presenting with laryngeal and voice disorders have laryngophathroat or a lump in your throat ryngeal reflux (LPR) as the primary cause or as a significant etio- 9. Heartburn, chest pain, indigestion, or 0 1 2 3 4 5 logical factor. Typical symptoms include chronic or intermittent stomach acid coming up dysphonia (especially in the morning), globus or a “tickle” sen- From: Belafsky PC, Postma G, Koufman JC (2002) Validity and relisation, excessive throat mucus, frequent throat clearing, chronic ability of the Reflux Symptom Index (RSI). J Voice 16:274–277

2  Principles of Clinical Evaluation for Voice Disorders

disorders resulting in hypoadduction of the vocal folds will present with a weak, breathy voice, vocal fatigue, and an ineffective cough. Such diseases include myasthenia gravis, muscular dystrophy, Parkinson’s disease, Shy–Drager syndrome, post-polio syndrome, traumatic brain injury, and abductor spasmodic dysphonia. Hyperfunctional neurological disorders are associated with a staccato or strained voice. These disorders include adductor spasmodic dysphonia, pseudobulbar palsy, and Huntington’s disease. Other neurological disorders present with mixed adductor and abductor components, making the dysphonia more difficult to diagnose. These disorders include multiple sclerosis, ataxic (cerebellar) dysphonia, and amyotrophic lateral sclerosis. Lastly, vocal tremor can be associated with Parkinson’s disease, benign essential tremor, spasmodic dysphonia, and palatopharyngeal myoclonus. Table 2.2 provides an overview of the historical elements of particular importance when obtaining a voice history. Table  2.3 demonstrates symptoms suggestive of specific voice disorders. Table 2.2  Special topics to include within a voice history History of Upper respiratory infection History of Endotracheal intubation Time course Prior Trauma Voice usage/demands Profession Vocal abuse Tobacco, alcohol, and drug use Dietary habits Foods precipitating reflux-related symptoms Hydration Allergy history Environmental history Climate Prescence of Heating and cooling units and impact on voice

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2.6 Past Surgical History A history of prior surgery is important to elicit with laryngeal dysfunction. In addition to questions concerning otolaryngological procedures, any procedure requiring general anesthesia and endotracheal intubation—even briefly—should be identified. Injuries associated with endotracheal intubation include arytenoid dislocation, vocal process granuloma, vocal fold paralysis/paresis from cuff pressure on the recurrent laryngeal nerves, posterior glottic stenosis, and interarytenoid adhesions. Although uncommon, injury to the membranous vocal fold (e.g., tissue loss) can result from direct injury by the endotracheal tube.

2.7 Social History The larynx’s central role in swallowing, breathing, and voice exposes it to multiple environmental and social behaviors. The voice disorder patient’s personal habits, diet, smoking, substance use, lifestyle, and occupation should be detailed. Even moderate consumption of alcohol is detrimental to the voice, through dehydration and effects on judgment. Caffeine, a diuretic, can affect the voice by thickening secretions and decreasing the efficiency of vocal fold vibration. Certain foods and alcohol predispose to gastroesophageal reflux. The deleterious effects of tobacco smoke on the vocal folds are well-documented. Both the smoke and heat produced by burning tobacco appear to contribute. Other fumes, such as stage smoke—particularly oil-based ones—can be of significance to vocal performance, especially stage actors. More recently, the use of electronic cigarettes and vaporizers has significantly increased. To date, little is known about the effects of these products on either the larynx or the voice, but details regarding their use should be obtained as part of collecting a thorough vocal history.

Table 2.3  Symptoms suggestive of specific voice disorders Symptoms Breathiness

Associated diagnoses Vocal fold paralysis (unilateral), vocal fold mass lesion Vocal fatigue Vocal fold atrophy or paralysis, neurogenic dysphonia Choking Vocal fold paralysis, CVA Odynophonia Vocal fold granuloma, MTD Paralaryngeal pain or Muscle tension dysphonia (primary or tension secondary) Laryngospasm LPR, gastroesophageal reflux disease, nerve injury, PVFMD Stridor Bilateral vocal fold paralysis, laryngeal stenosis, PVFMD Vocal tremor Parkinson’s disease, spasmodic dysphonia, benign essential tremor, myoclonus Velopharyngeal Myasthenia gravis, ALS, vagal paralysis insufficiency Globus LPR, neurological disease, MTD ALS amyotrophic lateral sclerosis, CVA cerebrovascular accident, LPR laryngopharyngeal reflux, MTD muscle tension dysphonia, PVFMD paradoxical vocal fold motion disorder

2.8 Occupational History The American Academy of Otolaryngology—Head and Neck Surgery defines a voice professional as “anyone whose voice is essential to their job.” The classic examples of voice professionals have included singers, actors/actresses, and television (TV) and radio personalities, but there are countless professionals of other occupations for whom their voice is vital: teachers and professors, coaches, attorneys, cashiers, clergy, receptionists, and those in telecommunications, sales, or customer service. Voice disorders affecting vocal professionals have a considerably greater impact on function than do those affecting nonprofessional voice users. Vocal needs and function vary widely among these groups. In general, questions about the duration of voice use as well as the frequency and duration of breaks can help clarify the level of vocal demands. Environmental factors (such as

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background noise or exposure to smoke, allergens, or pollutants) may also play a role. For performers, it can be important to inquire about the number and duration of rehearsals, the number of performances and duration of rest periods between performances, the size of the venue, use of amplification, the presence of an in-ear monitor, familiarity with the role, difficulty of the role, and the presence of an understudy. Teachers should be asked about the size of their class and of their classroom, whether or not they use amplification, whether they have any aides, student teachers, or other assistants, what type of subject matter they teach (i.e., music, gym, or other subjects), and what other school duties they have (e.g., recess or bus duty). Professors at the collegiate level may have not only longer teaching periods but also longer rest periods between lectures. Aspects of the history that affect income and job performance are important to detail, including absenteeism, economic loss, and unemployment. Although the description of vocal usage is useful as a general categorization, evaluation and therapy must be individually tailored to a person’s specific voice use setting and demands.

2.9 Listening to the Voice A critical part of the clinical evaluation is a careful subjective assessment of the patient’s voice. While taking the history, one should evaluate the quality of the patient’s speaking voice. The pitch of the voice and the rate and rhythm of speech should be noted. Posture and respiratory rate are important and should be noted during the encounter. Facial movements, especially around the mouth, as well as neck and shoulder movements should be examined for evidence of excess tension, tremors, or spasms. Consideration should be given to the efficiency of breath support during speech. Evidence of excess rate, volume, or tension during speech may indicate vocal abuse, which is highly prevalent in the dysphonic population. After careful patient observation, formal vocal testing may proceed by having the patient perform several different vocal tasks. After hearing normal speech, the patient may be asked to alter his or her type of vocal output, such as hum, sing, whisper, or yell. Moreover, the patient should alter the pitch, perform glissando, and use rapid alternating speech. Such vocal tasks will help the listener gain an insight into how vocal pathology affects the different aspects of the patient’s speech and may thus provide an insight into the nature of the vocal dysfunction. Additionally, various words or sounds call upon the coordination of different phonatory elements. Asking the patient to recite certain phrases will assist the clinician in characterizing the disorder. For instance, the word “taxi” can be used

P. C. Song and V. N. Young Table 2.4  Rainbow passage When the sunlight strikes raindrops in the air, they act like a prism and form a rainbow. The rainbow is a division of white light into many beautiful colors. These take the shape of a long round arch, with its path high above, and its two ends apparently beyond the horizon. There is, according to legend, a boiling pot of gold at one end. People look, but no one ever finds it. When a man looks for something beyond his reach, his friends say he is looking for the pot of gold at the end of the rainbow. Passage reprinted from Fairbanks G (1960) Voice and articulation handbook, p. 127. Copyright 1960 by Harper Collins Publishers, Inc

to elicit signs of abductor spasmodic dysphonia. The phoneme “kaa” requires good palatal lift and closure and “maa” requires mouth closure. The /m/ and /n/ phonemes require good nasal resonance and are useful for testing hyper- and hyponasality. The rainbow passage (Table  2.4), which is composed of every phoneme in the English language, is used as a standardized method of recording voice in order to track clinical progress.

2.10 Perceptual Analysis To evaluate the voice, the “trained” ear remains the most discerning instrument. Nonetheless, a standardized, objective instrument to characterize the voice remains an important goal of voice science. To this end, Hirano (1981) proposed the GRBAS (grade, roughness, breathiness, asthenia, strain) scale—a perceptual rating instrument widely used by speech pathologists and laryngologists for the evaluation of voice quality in clinical settings. This scale is a subjective perceptual evaluation of five vocal characteristics assigned a value between 0 and 3, where 0 is normal and 3 is extreme. The five elements are grade (G), a description of the degree of hoarseness; roughness (R), the perceptual irregularity of vocal fold vibrations, which is usually the result of a change in the fundamental frequency or amplitude of vibration; breathiness (B) or the assessment of air leakage through the glottis; asthenia (A) voice denotes weakness and lack of power; and strain (S), which reflects a perception of vocal hyperfunction. Another widely used auditory-perceptual evaluation of dysphonia is the Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V) (Table 2.5). This rating scale has been recently created by the Special Interest Division 3 of the American Speech-Language-Hearing Association as a standardized tool for assessment of the auditory-perceptual ­attributes of voice. Six salient features—overall dysphonia severity, roughness, breathiness, strain, pitch, and loudness—are rated by trained listeners (speech-language pathologists (SLPs) and laryngologists) using a 100-mm visual analogue scale for each parameter, with the option for additional user-defined parameters.

2  Principles of Clinical Evaluation for Voice Disorders Table 2.5 Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V) The following parameters of voice quality will be rated upon completion of the following tasks: 1. Sustain vowels, /a/ and /i/ for 3–5 s duration each 2. Sentence production:  (a) The blue spot is on the key again. (d) We eat eggs every Easter.  (b) How hard did he hit him? (e) My mama makes lemon muffins  (c) We were away a year ago. (f) Peter will keep at the peak. 3. Spontaneous speech in response to “Tell me about your voice problem” or “Tell me how your voice is functioning.” Legend: C = Consistent I = Intermittent  MI = Mildly Deviant  MO = Moderately Deviant  SE = Severely Deviant Score C I /100 Overall severity MI MO SE C I /100 Roughness MI MO SE C I /100 Breathiness MI MO SE C I /100 Strain MI MO SE Pitch (Indicate the nature of the abnormality): C I /100 MI MO SE Loudness (Indicate the nature of the abnormality): C I /100 MI MO SE C I /100 MI MO SE C I /100 MI MO SE Comments about resonance: Normal Other (provide description):

2.11 Quality-of-Life Questionnaires Much work has been performed to codify and measure patient self-perception of vocal dysfunction in the form of standardized questionnaires and other metrics. The Voice Handicap Index (VHI) is a quality-of-life questionnaire specific to voice disorders, which has excellent reliability and reproducibility. VHI assessment is a subjective patientbased questionnaire composed of 30 questions. Rosen et al. (2004) have introduced an abridged version composed of 10 questions, the VHI-10 (Table 2.6). This instrument is both easily self-administered and scored quickly at the time of evaluation while preserving the original VHI’s utility and validity. Because vocal pathologies have different levels of handicap to different individuals, these questionnaires are

15 Table 2.6  Voice Handicap Index-10 (VHI-10) My voice makes it difficult for people to hear me. People have difficulty understanding me in a noisy room. My voice difficulties restrict my personal and social life. I feel left out of conversations because of my voice. My voice problem causes me to lose income. I feel as though I have to strain to produce voice. The clarity of my voice is unpredictable. My voice problem upsets me. My voice makes me feel handicapped. People ask, “What’s wrong with your voice?”

0

1

2

3

4

0

1

2

3

4

0

1

2

3

4

0

1

2

3

4

0 0

1 1

2 2

3 3

4 4

0 0 0 0

1 1 1 1

2 2 2 2

3 3 3 3

4 4 4 4

From: Rosen CA, Lee AS, Osborne J, Zullo T, Murry T (2004) Development and validation of the voice handicap index-10 (VHI-10) Laryngoscope 114:1549–1556

extremely important for understanding the personal impact of these disorders on daily activities. For instance, vocal nodules that are devastating to a professional voice user may only be a minor inconvenience to a nonprofessional. The Voice-Related Quality-of-Life (V-RQOL) instrument has been validated and found to be useful (see Bibliography). Voice-related, patient-based surveys are helpful in quickly and accurately judging the patient’s perception of their degree of voice handicap.

2.12 Professional Speaking/Singing Voice A comprehensive and somewhat adapted historical background is necessary for the evaluation of the singing voice. The date of the next important performance, for instance, will determine whether management of the voice problem can be conservative—designed to assure the long-term protection of the larynx—or, rather, whether a more urgent intervention is needed in view of an impending important engagement. The length of time a singer has been performing is also important, especially if his or her performance career predates their formal vocal training. Undesirable singing techniques developed by amateur singers are particularly difficult to modify. Moreover, intermittent training, or training at the hand of multiple teachers/coaches, can often result in an incompatible amalgamation of techniques, requiring significant time and expert instruction to rectify. The settings in which the singer performs are of importance. Allergies to dust and mold can become major factors in older concert halls where curtains, backstage trappings, and cramped dressing room quarters are rarely cleaned. This is especially true if stage construction is underway during rehearsals. A history of recent or frequent airplane travel suggests an alternate source of mucosal irritation. Cabin air is dry, usually at

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5% or less humidity. Singers must therefore take care to maintain adequate laryngeal moisture by maintaining nasal breathing and constant hydration. Finally, exposure to stage smoke presents a unique problem, most prevalent among stage actors. Most stage smoke preparations, especially oil-­ based ones, can result in mucosal irritation, allergy, and bronchospasm, resulting in the commonly encountered complex of hoarseness, vocal “tickle,” and vocal fatigue. Key Points • Careful history taking and clinical evaluation are essential tools in the diagnostic evaluation of the voice disorder patient. • When caring for patients with voice disorders, the clinician should pay particular attention to the level of voice use, the importance of the voice to the patient, and the impact of the voice disorder on their quality of life and occupation. • Validated instruments such as the Voice Handicap Index10 (VHI-­10) are very useful tools for the evaluation of vocal complaints and may facilitate outcome assessment and monitoring over time. • A successful surgical outcome is dependent upon a thorough clinical evaluation of the patient’s voice disorder. It therefore behooves the serious practitioner of laryngology to focus not only on his or her surgical skills but also on evaluative and perceptual skills. This will ensure proper patient selection and lead to improved surgical outcomes.

Bibliography American Speech-Language-Hearing Association Special Interest Division 3: Voice and Voice Disorders. Voice disorders: Consensus auditory-perceptual evaluation of voice (CAPE–V). 2003. http:// www.asha.org. Bassich CJ, Ludlow DL. The use of perceptual methods by new clinicians for assessing voice quality. J Speech Hear Dis. 1986;51:125. Belafsky PC, Postma GN, Koufman JA. Validity and reliability of the reflux symptom index (RSI). J Voice. 2002;16:274–7.

P. C. Song and V. N. Young Benninger MS, Ahuja AS, Gardner G, Grywalski C.  Assessing outcomes for dysphonic patients. J Voice. 1998;12:540–50. Carding PN, Horsley IA, Docherty GD.  Measuring the effectiveness of voice therapy in a group of forty-five patients with non-organic dysphonia. J Voice. 1999;13:76–113. Cooper M.  Modern trends in voice rehabilitation. Springfield, IL: Charles C. Thomas; 1973. Courey MS, Postma GN. Microvascular lesions of the true vocal folds. Curr Opin Otolaryngol Head Neck Surg. 1996;4:134. Deary IJ, Wilson JA, Carding PN, et al. VoiSS, a patient-derived voice symptom scale. J Psychosom Res. 2003;54:483–9. Dejonckere PH, et  al. Perceptual evaluation of dysphonia: reliability and relevance. Folia Phoniatr (Basel). 1993;45:76. Hirano M. Clinical examination of the voice. New York, NY: Springer; 1981. Hogikyan ND, Rosen CA.  A review of outcome measurements for voice disorders. Otolaryngol Head Neck Surg. 2002;126:562–72. Hogikyan ND, Sethuraman G. Validation of an instrument to measure voice-related quality of life (V-RQOL). J Voice. 1999;13:557–69. Jacobson BH, Johnson A, Grywalsky C, et  al. The Voice Handicap Index (VHI): development and validation. Am J Speech Lang Pathol. 1997;6:66–70. Koufman JA. The otolaryngologic manifestations of gastroesophageal reflux disease. Laryngoscope. 1991;101(Suppl 53):1–78. Koufman JA, Isaacson G.  The spectrum of vocal dysfunction. Otolaryngol Clin N Am. 1991;24:985–8. Koufman JA, Amin MR, Panetti M. Prevalence of reflux in 113 consecutive patients with laryngeal and voice disorders. Otolaryngol Head Neck Surg. 2000;123:385–8. Erratum in: Otolaryngol Head Neck Surg. 124:104. Kreiman J, et al. Perceptual evaluation of voice quality: review, tutorial, and a framework for future research. J Speech Hear Res. 1993;36:21. Ma EP-M, Yiu EM-L. Voice activity and participation profile: assessing the impact of voice disorders on daily living. J Speech Lang Hear Res. 2001;44:511–24. Ritter FN.  Endocrinology. In: Paparella M, Shumrick D, editors. Otolaryngology. Philadelphia, PA: Saunders; 1973. p. 727–34. Rosen CA, Lee AS, Osborne J, Zullo T, Murray T.  Development and validation of the Voice Handicap Index-10. Laryngoscope. 2004;114:1549–56. Sataloff RT. Vocal fold hemorrhage: diagnosis and treatment. NATS J. 1995;45:1. Sataloff RT. Professional voice–the science and art of clinical care. 2nd ed. San Diego, CA: Singular; 1997. Silverman EM, Zimmer CH.  Effect of the menstrual cycle on voice quality. Arch Otolaryngol Head Neck Surg. 1978;104:7–10. Smith ME, Ramig LO. Neurological disorders and the voice. In: Rubin JS, Sataloff RT, Korovin GS, et al., editors. Diagnosis and treatment of voice disorders. New York, NY: Igaku-Shoin; 1995. p. 203–19.

3

Videostroboscopy and Dynamic Voice Evaluation with Flexible Laryngoscopy Clark A. Rosen and C. Blake Simpson

Commentary by Peak Woo, MD

3.1

Fundamental and Related Chapters

Please see Chapter 1—“Anatomy and Physiology of the Larynx”, Chapter 2—“Principles of Clinical Evaluation for Voice Disorders”, Chapter 4—“Pathological Conditions of the Vocal Fold”, and Chapter 5—“Glottic Insufficiency: Vocal Fold Paralysis, Paresis, and Atrophy” for further information.

3.2

Introduction

Visualization of the larynx, specifically the vocal folds, is of great importance to the evaluation and care of patients with laryngeal disorders. There are a variety of methods used for this visualization, ranging from indirect mirror laryngoscopy to high-speed photography. The most common and relevant clinical tools for modern-day voice evaluation and care include stroboscopic visualization of vocal fold vibrations and dynamic voice evaluation with flexible laryngoscopy. These two techniques, when used in a complimentary manCommentary by Peak Woo MD. Department of Otolaryngology, Icahn School of Medicine at Mount Sinai, New York, NY, USA Supplementary Information The online version contains supplementary material available at https://doi.org/10.1007/978-3-031-34354-4_3. C. A. Rosen (*) UCSF Voice & Swallowing Center, Department of Otolaryngology-Head & Neck Surgery, University of California, San Francisco, San Francisco, CA, USA e-mail: [email protected] C. B. Simpson Department of Otolaryngology—Head and Neck Surgery, University of Alabama at Birmingham, Birmingham, AL, USA e-mail: [email protected]

ner, can provide the clinician with detailed information on intricate vocal fold vibratory activity and phonatory and functional use of the entire vocal tract. This chapter focuses on these two main clinical methods. Commentary An important aspect is the complementary use of flexible laryngoscopy and videostroboscopy in evaluation of laryngeal diseases. Although flexible video laryngoscopy using Stroboscopy light is now commonly used as a single procedure, the higher magnification and improved definition with high definition 3 chip camera cannot yet be matched with a flexible endoscope. Therefore the clinician should have well-defined indications for each. Sometimes a flexible laryngoscopy with dynamic imaging of vocal fold motion should be considered versus while in other conditions a videostroboscopy should be considered first. I prefer to start with rigid videostroboscopy indications with a veiled voice quality or rough voice quality. A flexible laryngoscopy is preferred first in patients with neurological conditions. This includes: laryngeal dystonia (spasmodic dysphonia), tremor, breathy dysphonia, or paralysis. While videostroboscopy allows one to evaluate vibratory function, it is only appropriate in patients with quasi-periodic vocal fold vibration. In patients with chaotic periodic vibration, high-speed video should be considered to look for alternative sites of vocal fold vibration or aperiodic vibration.

3.3

Stroboscopy

Stroboscopy utilizes the method of “shuttering” or synchronized illumination of the vocal folds during vocal fold vibrations (Fig.  3.1). This provides “pseudo” slow motion visualization of the vocal fold vibrations. A real-time vocal

© Springer Nature Switzerland AG 2024 C. A. Rosen, C. B. Simpson, Operative Techniques in Laryngology, https://doi.org/10.1007/978-3-031-34354-4_3

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C. A. Rosen and C. B. Simpson

Fig. 3.1  A “representative” set of images from stroboscopy depicting “one” vibratory cycle

fold vibration is too rapid to visualize with the unaided eye. Stroboscopic light source illumination provides representative images from the entire vibratory cycle. A periodic or a nearly periodic vocal fold vibratory activity is required for stroboscopy to be successful. It is important to note that stroboscopy can be performed using any type of visualization instrument, including a flexible laryngoscope and a rigid perioral laryngoscope. Stroboscopy is strictly the light source and not the actual equipment used for visualization of the vocal folds (i.e., a flexible laryngoscope or a rigid telescope). The most common vocal fold vibratory characteristics that stroboscopy allows one to view are as follows: • • • • •

Vocal fold closure (pattern and duration) Mucosal wave movement (propagation) Symmetry of vibration Amplitude of vocal fold vibration Periodicity

Stroboscopy helps elucidate specific lesions of the vocal folds, especially as they relate to the closure pattern of exophytic lesions and to the defects of the lamina propria, such as those seen in the adynamic segments of the vocal folds, vocal

fold scar, and sulcus deformity of the vocal fold. A vocal fold closure pattern is typically described as the global overall pattern of vocal fold closure, as seen during the majority of the examinations, specifically at modal pitch and intensity (sustained phonation). The most commonly cited and utilized closure patterns include: complete, incomplete, hourglass, anterior glottic gap, and excessive posterior glottic gap (Fig. 3.2). A mucosal wave, as seen during stroboscopy, refers to a rippling motion traveling over the vocal fold and within the vocal fold’s mucosa. Such a wave is propagated from the subglottic area and travels from underneath the vocal fold along the free edge, then over the superior surface of the vocal fold, and is dampened in the area of the ventricle. This mucosal wave activity is crucial for assessing the pliability and functional characteristics of the lamina propria of the vocal folds. Areas of a diminished mucosal wave represent loss of pliability or viscoelasticity of the vocal fold’s lamina propria and are an important aspect of voice evaluation. Mucosal wave activity should be assessed using a variety of phonatory tasks, specifically at low, medium, and high pitches and at different levels of intensity. The duration of vocal fold closure is also an important clinical assessment parameter. At modal pitch and intensity, vocal fold vibratory closure should occur at approximately

3  Videostroboscopy and Dynamic Voice Evaluation with Flexible Laryngoscopy

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Fig. 3.2  Different vocal fold closure patterns

half of the vibratory cycle. This can be measured in a detailed manner using electroglottography but can also be estimated using a frame-by-frame review of the recorded stroboscopic images (taking care to control for pitch and intensity) (Video 3.1). Vocal fold vibration symmetry during stroboscopy is judged by comparing one vocal fold’s vibratory activity with that of another. The vibration of one vocal fold should be a mirror image of the contralateral fold. The degree of vocal fold amplitude (horizontal excursion from the midline) during vocal fold vibrations, as seen during stroboscopy, is an important assessment tool and involves both comparative and overall subjective assessments of the amount of amplitude of each vocal fold during vocal fold vibrations (Fig. 3.3). Of course, both amplitude and closure are two stroboscopic parameters that are directly affected by voice intensity and pitch during the stroboscopic examination, and these factors must be constantly monitored and taken into consideration when assessing these parameters. For example, at a high pitch, both the amplitude and mucosal wave decrease as compared to lower pitches.

Fig. 3.3  Vocal fold amplitude

Periodicity describes the regularity of a vocal fold vibration. It is based on the regularity of successive cycles of a vibration. Even though symmetry and periodicity may be the main param-

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eters used to assess similar behavior, in fact, vocal folds also exhibit distinctly different amplitudes and asymmetric activity and still be quite periodic. The converse is also true, i.e., vocal folds can demonstrate aperiodic activity with normal and symmetric amplitude (as often seen in vocal fold paresis). Stroboscopy of the vocal folds is helpful for visualization of a variety of vocal fold lesions, which are discussed in detail in Chapter 4—“Pathological Conditions of the Vocal Folds.” Stroboscopy is also extremely important for visualization of segments of the vocal folds with poor vibratory characteristics due to vocal fold scar, loss of the lamina propria tissue, or sulcus deformities of the vocal fold (see Chapter 25—“Vocal Fold Scar and Sulcus Deformities of the Vocal Fold”). Stroboscopy, to assess vocal fold vibratory activity, should be performed using a fairly consistent assessment protocol. First, it is essential to identify whether the patient has a periodic or a nearly periodic signal. A typical stroboscopic examination protocol includes: • Modal voice (most comfortable pitch and intensity) • Low pitch (soft and loud to assess the maximum pliability) • A high-pitch, soft-intensity phonatory task The latter is extremely helpful for identifying subtle lesions of the vocal folds as well as for assessing abnormalities associated with vocal fold pliability and vocal fold vibratory activities. In patients, a low-pitch loud task is helpful for assessing not only their overall vocal fold pliability but also their most aperiodic voice. When performing stroboscopy, the vocal fold vibratory activity and characteristics should be first compared internally (to each other) and then compared to the examiners experiential database and, most importantly, correlated with the amount and nature of the patient’s dysphonia. There should be a good correlation from an auditory and visual perceptual point of view. If this is not the case, then a repeat or careful examination of the other factors should be undertaken. Commentary Since videostroboscopy interpretation is a subjective interpretation based on the vibratory characteristics of the vocal folds during production of a specific vocal gesture, and we know that vocal fold vibration is capable of great variations in configuration, amplitude and mucosal wave, the examiner should be systematic in testing for each gesture. This suggested four tokens used for testing includes: Modal phonation, high pitch phonation, low pitched phonation, and loud phonation. In this way, the examiner can see the effect of Stroboscopy changes with frequency, loudness and with register transition. Separate norms for stroboscopic examina-

C. A. Rosen and C. B. Simpson

tion based on gender and age differences also exist. Therefore, standard isolation of the token is important.

3.4 Dynamic Voice Assessment with Flexible Laryngoscopy Flexible laryngoscopy is an essential evaluation technique for voice disorder-related “functional” problems such as muscle tension dysphonia, paradoxical vocal fold motion disorder, functional aphonia, neurological voice disorders (laryngeal dystonia/spasmodic dysphonia, essential tremor, etc.), and vocal fold motion impairment (paralysis, paresis, etc.). Dynamic voice assessment with flexible laryngoscopy evaluates the multiple parameters associated with phonation conducted in a dynamic and “most natural” setting. The equipment required include a nasal speculum, a decongestant and an anesthetic for the nasal cavity, a flexible laryngoscope, and illumination light source(s) (continuous halogen and preferably stroboscopy). This examination is conducted in a stepwise manner, examining each section of the vocal tract, which is outlined in Table 3.1 from an anatomical and a physiological perspective (at rest and then in activation). The specific areas of activation include vegetative functions and phonation. The subregions of the dynamic voice assessment include the nasopharynx, base of the tongue, larynx (global), and vocal folds. At each one of these specific sub-portions of the dynamic voice assessment, specific tasks are elicited from the patient to look for different pathologies in the area and to either confirm or rule out a variety of disorders (Table 3.1).

Table 3.1  Dynamic Voice Assessment tasks, findings, and correlated diagnoses: examination protocol— Velum tasks  Sustained /ee/  /koka kola/ Base of the tongue  Evaluation of symmetry and the mucosa Larynx  Quiet respiration  Sustained /ee/—comfortable pitch  Sustained /ee/—low and high pitch  /ee/ /ee/ /ee/ (with a breath between each “hee”)  Perform three sniffs in a row  “We were away a year ago.”—comfortable pitch  Example of connected speech (Ask, “What did you do yesterday?”)  Sing “Happy Birthday”  Cough  Laugh

3  Videostroboscopy and Dynamic Voice Evaluation with Flexible Laryngoscopy

3.4.1 Nasopharynx

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1. Patient task: Rest, sustained phonation (/ee/) and speech (/koka kola/), and prolonged fricative /s/ 2. Parameters of evaluation: Nasal disease, masses of the nasopharynx, tremor of the soft palate (rest and activation), and velopharyngeal insufficiency (VPI) 3. Pathology: Velopharyngeal insufficiency, vocal tremor, sinonasal disease (infectious or allergic), and nasopharyngeal neoplasms

Commentary Dynamic assessment of vocal function especially in patients suspected of neurological conditions or vocal fold paresis. Flexible laryngoscopy may be used to test for vocal fatigue by repetitive testing. This can be done with the “ee-sniff” gesture done respectively over 30–60  s to see if there is vocal fatigue. In addition, the diadochokinesis rate of vocal fold adduction followed by deep inspiration can also be recorded. This can be helpful in diagnosis of subtle vocal fold paresis.

3.4.2 Base of the Tongue

3.5 Recording of Laryngeal Examination

1. Patient task: Rest and tongue protrusion 2. Parameters of evaluation: Tremors, fasciculations, tumors, and infections 3. Pathology: Essential tremor of the vocal tract, amyotrophic lateral sclerosis (ALS), neoplasms (benign and malignant), and infection

It is highly recommended, but not absolutely necessary, that the stroboscopy and/or dynamic voice evaluation be recorded. The two most common methods of recording portions or all of these examinations are either still photography or video recording. The advantages of recording all or portions of laryngeal examinations include:

3.4.3 Larynx (Global) 1. Patient task: Quiet respiration, alternating sustained phonation and respiration (hee-hee-hee, with a breath between each “hee”), and connected speech (“We were away a year ago.”) 2. Parameters of evaluation: Vocal fold mobility and synchrony of mobility, paradoxical vocal fold motion, supraglottic constriction associated with phonation, and laryngeal tremor (pharyngeal walls, vertical motion of the larynx, and supraglottis) 3. Pathology: Paradoxical vocal fold motion disorder, primary muscle tension dysphonia, secondary muscle tension dysphonia, vocal tremor, vocal fold paralysis, vocal fold paresis, pyriform/vallecular lesion(s), and laryngopharyngeal reflux disease (LPRD) (Video 3.2)

3.4.4 Vocal Folds (Focal) 1. Patient task: Respiration, sustained phonation, and alternating speech and respiration (see Table 3.1) 2. Parameters of evaluation: Vocal fold lesions, glottic insufficiency, and tremor 3. Pathology: Focal vocal fold lesions (polyp, nodules, etc.), cancer, vocal fold atrophy, vocal fold paralysis, and vocal fold paresis

• • • •

Longitudinal comparison Preoperative planning Patient education Medical/legal uses

Further justification and use of a video recording include the ability to record an audio track in conjunction with the video examination. Both audio and video examinations can be extremely helpful for all of the abovementioned reasons, especially in a court of law. It is essential to have a baseline or preoperative audio and/or voice recording prior to and after elective surgical procedures. This is analogous to the documentation procedures for cosmetic surgical procedures. Video recordings of the vibratory parameters of the vocal folds are also extremely helpful to refer to when surgically resecting a lesion. Commentary Video laryngoscopy imaging with video stroboscopy serves as a critical control of phonosurgery techniques as the role of phonosurgery is the restoration of vocal fold vibratory function. Comparison of the rate of mucosal wave restoration in surgical techniques such as vocal fold stripping versus laser ablation for epithelial diseases services one example where video Stroboscopy performed in series can be helpful to compare surgical techniques.

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3.6 High-Speed Video (HSV) Examination of the Larynx Technological advancement in the area of imaging of the larynx has led to the development of high-speed visualization and recording of vocal fold vibrations. In the 1970s, this type of imaging was expensive, onerous, and could only be performed for an extremely short time period. Now, high-speed cameras can capture images from 2000 to 10,000 frames per second and the imaging can be digitally captured. High-­speed video (HSV) is now relatively affordable, and it is reasonable to store and review the recorded video. HSV has a potential major advantage over stroboscopy since it provides imaging of all vocal fold vibratory activities and is not dependent on a periodic signal. Despite these major advances, HSV is not ready to become a routine, clinically useful voice assessment instrument. Limitations persist in the form of an efficient and reliable methodology for review of the recorded video and interpretation of the findings. At present, HSV examination can only be carried out through a rigid, peroral “Hopkins” rod, which is another limitation. Pediatric voice care providers have advocated for HSV examination due to the short duration of the examination period frequently encountered in pediatric patients, but clinical relevance is still pending (Video 3.3). Commentary High-speed video laryngoscopy has the potential of overcoming the deficiencies a videostroboscopy, especially in patients with chaotic voice, patients with diplophonia, and patients with voice onset abnormalities such as spasmodic dysphonia and muscle tension dysphonia.

3.7 Videokymography (VKG) Videokymography (VKG) or a line-scan camera is a laryngeal imaging modality that provides “real-time” visualization of vocal fold vibrations. It can be carried out using a dedicated VKG camera or extracted from an HSV recording. VKG captures images from one active horizontal line (perpendicular to the longitudinal axis of the vocal folds) and takes the horizontal images and “stacks” them on top of each other to provide detailed information about the medial–lateral excursion and vibratory activity of the vocal folds during vibration. VKG can provide information about asymmetric vibrations, open quotient, and mucosal wave activity. It has many advantages over stroboscopy, and it is cheaper and less digital memory-consuming than HSV, but VKG has not yet become a widely used clinical tool for laryngeal evaluation (Video 3.4).

C. A. Rosen and C. B. Simpson

Commentary With the use of high-speed digital imaging, it is possible to perform digital Video kymography and transferred the Video kymography to an analyzable wave form for objective analysis. Key Points • Stroboscopy and dynamic voice assessment (DVA) with flexible laryngoscopy are the essential aspects of voice evaluation and care. • Stroboscopy and DVA are complementary and should not be viewed in isolation. • Dynamic voice assessment and evaluation allows for a natural in vivo evaluation of the entire vocal tract during rest, vegetative activities, and phonation (connected and sustained), and stroboscopy allows the examiner insights into the key vocal fold vibratory activities, specifically the physiological and pathophysiological activities related to the patient’s dysphonia. • The combination of stroboscopy and dynamic voice assessment with flexible laryngoscopy allows the clinician to correlate the patient’s voice symptoms with the related physical exam findings of any abnormality to make an accurate diagnosis, and formulate a successful treatment plan.

Bibliography Bonilha HS, Focht KL, Martin-Harris B. Rater methodology for stroboscopy: a systematic review. J Voice. 2015;29(1):101–8. Bonilha HS, Desjardins M, Garand KL, Martin-Harris B.  Parameters and scales used to assess and report findings from stroboscopy: a systematic review. J Voice. 2018;32(6):734–55. Cornut G, Bouchayer M, Carding P, Rugheimer G. Assessing dysphonia: the role of videostroboscopy. Lincoln Park, NJ: Kay Elemetrics; 2004. 3 videodiscs, 256 min. Hirano M, Bless DM.  Videostroboscopic examination of the larynx. San Diego, CA: Singular; 1993. Phadke KV, Vydrová J, Domagalská R, Švec JG. Evaluation of clinical value of videokymography for diagnosis and treatment of voice disorders. Eur Arch Otorhinolaryngol. 2017;274(11):3941–9. Roehm PC, Rosen C. Dynamic voice assessment using flexible laryngoscopy—how I do it: a targeted problem and its solution. Am J Otolaryngol. 2004;25:138–41. Rosen CA. Stroboscopy as a research instrument: development of a perceptual evaluation tool. Laryngoscope. 2005;115:423–8. Stasney CR.  Atlas of dynamic laryngeal pathology. San Diego, CA: Singular; 1996. Zacharias SRC, Deliyski DD, Gerlach TT.  Utility of laryngeal high-­ speed videoendoscopy in clinical voice assessment. J Voice. 2018;32(2):216–20.

4

Pathological Conditions of the Vocal Fold Laura Dominguez, Clark A. Rosen, and C. Blake Simpson

4.1

Fundamental and Related Chapters

Please see Chapter 2—“Principles of Clinical Evaluation for Voice Disorders”, Chapter 3—“Videostroboscopy and Dynamic Voice Evaluation with Flexible Laryngoscopy”, Chapter 12—“Principles of Phonomicrosurgery”, Chapter 18—“Vocal Fold Polyp and Reactive Lesion: Phonomicrosurgery”, Chapter 19—“Vocal Fold Cyst and Vocal Fold Fibrous Mass”, Chapter 20—“Reinke’s Edema”, Chapter 21—“Vocal Fold Granuloma”, Chapter 22—“Vocal Fold Leukoplakia and Epithelial Dysplasia: Phonomicrosurgery”, Chapter 23—“Surgical Treatment of Recurrent Respiratory Papillomatosis of the Larynx”, Chapter 24—“Vascular Lesions of the Vocal Fold: Phonomicrosurgery”, Chapter 25—“Vocal Fold Scar and Sulcus Deformities of the Vocal Fold”, and Chapter 41—“Awake Laser Treatment for Benign Laryngeal Pathology” for further information.

4.2

Introduction

The variety of pathological conditions that occur within the vocal folds can be separated into categories based on their anatomical location. In this chapter, a brief overview and disSupplementary Information The online version contains supplementary material available at https://doi.org/10.1007/978-3-031-34354-4_4. L. Dominguez (*) Department of Otolaryngology, Cleveland Clinic Florida, Coral Springs, FL, USA e-mail: [email protected] C. A. Rosen UCSF Voice & Swallowing Center, Department of Otolaryngology-Head & Neck Surgery, University of California, San Francisco, San Francisco, CA, USA e-mail: [email protected] C. B. Simpson Department of Otolaryngology—Head and Neck Surgery, University of Alabama at Birmingham, Birmingham, AL, USA e-mail: [email protected]

cussion of the key points of the epithelial pathology of the vocal folds, benign mid-membranous lesions, and miscellaneous vocal fold pathologies, especially as they relate to surgical treatment, are provided. It should be stressed that with the exclusion of carcinoma and recurrent respiratory papilloma of the vocal folds, most of the vocal fold lesions are benign and in general should be managed with a conservative approach that involves maximizing all nonsurgical treatment methods first and only then proceeding with surgical treatment if the key functional issues (i.e., voice quality and vocal function) are still persistent.

4.3

Epithelial Pathology of the Vocal Folds

4.3.1

Recurrent Respiratory Papillomatosis (RRP) of the Larynx

Recurrent respiratory papillomatosis of the larynx is an epithelial growth of the larynx most commonly seen at the level of the vocal folds (Fig. 4.1). These growths are a direct response to a human papilloma virus (HPV) infection and tend to be recurrent in nature. The most common human papilloma virus types involved with RRP of the larynx are HPV types 6 and 11. These recurrent benign lesions grow most significantly at epithelial transition sites, such as where pseudostratified columnar and stratified squamous epithelia are juxtaposed. Any time that a new epithelial transition site is created in a patient who is infected with the human papilloma virus, there is a high risk of a new papillomatous disease growth at that site(s). This is often seen when a tracheotomy is performed on a patient with recurrent respiratory papillomatosis. Malignant transformation of these types of HPV infections are extremely rare, and historical experience has demonstrated that external beam radiation therapy, tobacco exposure, pulmonary involvement, and alcohol exposure increase the risk of RRP malignant transformation. It cannot be overemphasized that the chance of curing patients with RRP using surgical excision alone is low; likewise,

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Fig. 4.1  Recurrent respiratory papillomatosis, bilateral

there is no evidence that a more aggressive operation will increase the patient’s long-term control of his or her disease. The surgical philosophical approach to RRP should be to: (1) maintain a patent airway without using a tracheotomy, (2) optimize functional results with respect to voice and swallowing, and (3) minimize the chance of operative complications and sequelae such as glottic webbing and vocal fold scar formation.

4.3.2 Leukoplakia of the Vocal Folds The term “leukoplakia” is Latin for white patch and is truly just a physical exam finding on the vocal fold. Abnormal epithelial hypertrophy or dysplasia of the vocal fold epithelium can be manifested as redundancy of the epithelial or ­keratotic layers of the vocal folds, resulting in hyperkeratosis and parakeratosis, and is clinically referred to as leukoplakia (Fig. 4.2). An important differentiation of this pathology relates to the anatomical struc-

Fig. 4.2  Keratosis of the left vocal fold

L. Dominguez et al.

ture of the cells involved in the abnormal epithelium. Often, these cells are or can become dysplastic and are believed to be a precursor to a malignancy. However, many patients who suffer from keratosis of the vocal folds show no dysplasia of these lesions and are strictly burdened by the repetitive regrowth of a hyperkeratotic epithelial covering at various locations of the vocal folds. These lesions can be singular in nature or they can be multiple and diffuse throughout the vocal folds and arytenoid cartilages. Given that the risk of transformation of this leukoplakic biological activity into a malignancy is present (statistically 50 are generally seen with clinically significant upper airway stenosis. In addition, handheld devices and smartphone apps are available for the patient to measure and keep track of their peak flow over time.

Fig. 6.5  A normal flow-volume loop

6.6.3 Radiographic Studies A fine-cut (1 mm) computed tomography (CT) scan of the airway (neck and chest) with contrast is helpful in the evaluation of suspected airway obstruction. This is especially true in cases of suspected external compression or cartilage collapse (Fig. 6.7). These conditions are often contraindications to an endoscopic laser approach. It is important to remember that radiographic studies of the airway only provide a static view of the airway. Dynamic collapse of

6  Glottic and Subglottic Stenosis: Evaluation and Surgical Planning

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Fig. 6.7  Computerized tomographic image of the trachea (axial), demonstrating collapse of the cartilaginous tracheal walls, resulting in airway narrowing. There is no evidence of intraluminal scarring or soft tissue obstruction

6.7 Glottic and Subglottic Stenosis: Surgical Planning Fig. 6.6  A flow-volume loop of a patient with subglottic stenosis, demonstrating “flattening” of the inspiratory limb. This is commonly referred to as a “fixed extrathoracic obstructive pattern”

the airway (e.g., tracheomalacia) can only be ruled out with a flexible endoscopic examination of the entire upper airway.

In most cases, the initial microlaryngoscopy/tracheobroncho scopy is planned as a therapeutic surgery. In certain instances, however, it may be appropriate to perform an airway endoscopy in the operating room strictly for diagnostic purposes. Examples include:

• Incomplete office/radiographic evaluation of the airways—in this case, additional information (via operative endoscopy) needs to be obtained before a definitive treatment plan can be implemented. In some cases, 6.6.4 Laboratory Testing patients may present with a long-standing cuffed tracheostomy tube that is difficult or dangerous to remove at a In a small handful of patients, there is no obvious traumatic/ clinic due to the risk of bleeding/loss of airway. In these iatrogenic cause of the patient’s subglottic/tracheal narrowcases, it is best to complete the airway examination in a ing. In these cases, one must have a high degree of suspicion controlled environment such as the operating room. for an underlying inflammatory/autoimmune or neoplastic • Suspicion of a malignancy or systemic disease—these cause. Those patients in whom an etiology cannot be estabcases should be evaluated with biopsy in the operating lished fall under the category of idiopathic. These patients room. Definitive treatment may need to be delayed until a are frequently perimenopausal Caucasian women with a histological and/or microbiological diagnosis is obtained recurrent stenosis that develops at the junction of the cricoid or the systemic disease is treated medically. and first tracheal ring. • Evaluation and mapping of stenosis as an aid to planning In these cases, the following protocol may be used: an external procedure—in this instance, the patient is known to have a stenosis that is not amendable to endo• Antineutrophil cytoplasmic antibody, cytoplasmic (c-ANCA) testing, autoimmune profile, angiotensin-­ scopic treatment; however, anatomic mapping of the stenosis and tracheostomy location are obtained to aid in the converting enzyme (ACE) level serum testing selection of the appropriate external surgical approach. • Biopsies of the involved tissue (histopathology and culture) (See Chapter 34—“Subglottic/Tracheal Stenosis: • Selective pH probe testing for LPR in indicated cases Endoscopic Management” for details on mapping the • Rheumatological evaluation extent of the stenosis.)

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6.7.1 Corrective Surgical Procedures for Glottic/Subglottic Stenosis

6.7.2 Criteria for Endoscopic Treatment of Subglottic Stenosis

These procedures are listed in order from the least invasive to the most invasive approach.

Criteria include:

• Endoscopic procedures (microlaryngoscopy, laser excision/radial incisions, balloon or rigid dilation) • Endoscopic procedures with indwelling stent placement –– T-tube stent with an external limb (long-term) –– Intraluminal stent (short-term, palliative) Dumon, Wall, Ultraflex, etc. • Endoscopic procedures with posterior cartilaginous graft placement • External procedures –– Laryngotracheoplasty with cartilage grafting (airway expansion) –– Tracheal or cricotracheal resection with primary anastomosis –– Slide tracheoplasty In general, the least invasive procedures are attempted first (unless contraindicated), saving the external procedures for those cases that fail to respond to an endoscopic approach. Airway stenting is a “middle ground” between endoscopic and external procedures; however, it is not widely practiced and requires experience to achieve consistent results. T-tube stenting is generally more successful in long-term stenosis treatment than are intraluminal stents, which have a tendency to migrate and incite granulation tissue formation. In general, intraluminal stents are not appropriate for long-term treatment of stenosis. These stents are better suited for palliative airway obstruction from metastatic tumor infiltration of the airways and in patients with terminal disease. External procedures are indicated when endoscopic treatments are contraindicated or are unsuccessful. In general, the morbidity and mortality of these procedures are significantly higher than those of endoscopic treatments. Patients with significant comorbidities and advanced age may not be suitable candidates for external stenosis treatment. Tracheostomy, although not a “corrective” procedure for airway stenosis, may be the appropriate treatment of extensive stenosis in patients with poor medical health or when all treatments fail.

• No external compression, tracheomalacia, or significant cartilage collapse • Length of stenosis no more than 2–3 cm • Identifiable airway lumen • If present, tracheostomy entry point not involving/adjacent to the stenotic site1

6.7.3 Criteria for T-Tube Stenting for Subglottic Stenosis • Tracheotomized patients with subglottic/tracheal narrowing (from any cause) who have failed serial CO2 radial incisions/dilation treatment. Complete stenosis is “not” a contraindication to this technique. • Proximal subglottic/infraglottic region free of stenosis –– A normal airway of 7–8 mm in length below the vocal folds –– Accommodates the proximal limb of the T-tube, without impingement on the vocal folds

6.7.4 Criteria for External Treatment of Glottic/Subglottic Stenosis • Failure of endoscopic and/or T-tube stent treatments • Extensive stenosis (no identifiable lumen, length greater than 3 cm) • Tracheomalacia, cartilage collapse It should be noted that the above recommendations are not the absolute criteria for selecting external treatment approaches; they simply represent the general guidelines. Certainly, patients with lesser degrees of stenosis have failed endoscopic management, whereas those with more extensive 1  Repetitive mechanical trauma from the tracheostomy tube postoperatively has an adverse effect on the healing of airway stenosis. Thus, if a tracheostomy tube is present, the stenotic region ideally should not extend down to the entry point of the tracheotomy.

6  Glottic and Subglottic Stenosis: Evaluation and Surgical Planning

stenosis have occasionally responded favorably to endoscopic treatment. The surgeon should use his/her judgment in determining the suitability of the endoscopic approach. Key Points • Laryngotracheal airway obstruction is generally caused by trauma to the upper airway from prolonged endotracheal intubation, which leads to pressure necrosis, ­granulation tissue, localized infection, and cicatrix formation. The risk of airway stenosis markedly increases after 10 days of intubation. • Tracheostomy can lead to delayed tracheal stenosis (typically 1–3 months after decannulation) and is typically due to collapse/contraction of the cartilaginous support. • Nontraumatic subglottic narrowing should be thoroughly investigated to rule out associated inflammatory, autoimmune, and neoplastic conditions. • Physical examination of a patient with suspected laryngotracheal stenosis should include a flexible laryngoscopy and tracheoscopy (down to the carina) in the clinic setting, using topical lidocaine for endolaryngeal/tracheal anesthesia. • Radiographic airway studies are essential if external compression is suspected but do not replace a laryngoscopic airway evaluation. • Corrective surgical procedures for laryngotracheal stenosis include endoscopic management (microlaryngoscopy with laser radial incisions with dilation), indwelling stent placement, and external treatments (cartilage expansion grafts vs. segmental resection and primary anastomosis). • In patients with laryngotracheal stenosis, the least invasive surgical procedures are attempted first (unless contraindicated), reserving external procedures for those cases that fail to respond to an endoscopic approach. • Medical comorbidities (diabetes mellitus, restrictive or obstructive pulmonary disease, and obstructive sleep apnea) may have a significant negative impact on the surgical outcome and should be carefully considered prior to undertaking these treatments.

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Bibliography Amin MR, Simpson CB. Office evaluation of the tracheobronchial tree. Ear Nose Throat J. 2004;83(Suppl):10–2. Belafsky PC, Mouadeb DA, Rees CJ, Pryor JC, Postma CN, Allen J, Leonard RJ. Validity and reliability of the Eating Assessment Tool (EAT-10). Ann Otol Rhinol Laryngol. 2008;117(12):919–24. Benjamin B.  Prolonged intubation injuries of the larynx: endoscopic diagnosis, classification, and treatment. Ann Otol Rhinol Laryngol. 1993;160(Suppl):1–15. Gardner GM, Courey MS, Ossoff RH. Operative evaluation of airway obstruction. Otolaryngol Clin N Am. 1995;1995(28):737–50. Gartner-Schmidt JL, Shembel AC, Zullo TG, Rosen CA. Development and validation of the Dyspnea Index (DI): a severity index for upper airway-related dyspnea. J Voice. 2014;28(6):775–82. Gelbard A, Francis DO, Sandulache VC, et  al. Causes and consequences of adult laryngotracheal stenosis. Laryngoscope. 2015;125(5):1137–43. Lano CF Jr, Duncavage JA, Reinisch L, Ossoff RH, Courey MS, Netterville JL.  Laryngotracheal reconstruction in the adult: a ten-­ year experience. Ann Otol Rhinol Laryngol. 1998;107:92–7. McCaffrey TV.  Management of subglottic stenosis in the adult. Ann Otol Rhinol Laryngol. 1991;100:90–4. Nouraei SA, Nouraei SM, Patel A, et al. Diagnosis of laryngotracheal stenosis from routine pulmonary physiology using the expiratory disproportion index. Laryngoscope. 2013;123(12):3099–104. Rosen CA, Lee AS, Osborne J, Zullo T, Murry T.  Development and validation of the voice handicap index-10. Laryngoscope. 2004;114(9):1549–56. Shapshay SM, Beamis JF, Hybels RL, et al. Endoscopic treatment for subglottic and tracheal stenosis by radial laser incision and dilation. Ann Otol Rhinol Laryngol. 1987;6:661–4.

7

Nonsurgical Treatment of Voice Disorders Priya Krishna and Clark A. Rosen

7.1

Fundamental and Related Chapters

Please see Chapter 2—“Principles of Clinical Evaluation for Voice Disorders”, Chapter 4—“Pathological Conditions of the Vocal Fold”, Chapter 5—“Glottic Insufficiency: Vocal Fold Paralysis, Paresis, and Atrophy”, and Chapter 8—“Laryngopharyngeal Reflux Disease” for further information.

7.2

Laryngopharyngeal Reflux Disease

In all, 4%–10% of otolaryngological visits are related to gastroesophageal reflux disease (GERD)-related laryngeal complaints. Up to 50% of voice disorder patients may have coexisting laryngopharyngeal reflux disease (LPRD). LPRD manifests in many ways: sore throat, globus, hoarseness, throat clearing, dysphagia, chronic cough, and postnasal drip. The diagnosis of LPRD is often based on patient history and laryngeal signs noted during laryngoscopy. These include edema and erythema of the larynx, pseudosulcus (infraglottic edema), Reinke’s edema, interarytenoid mucosal changes, contact ulcers, granulomas, and mucosal cobblestoning of the posterior pharynx. LPRD CAN BE associated with paradoxical vocal fold motion disorder (PVFMD) and asthma. It is also linked to the development of leukoplakia and, potentially, laryngeal cancer. Studies have alluded to the frequent association of LPRD and/or gastroesophageal reflux disease (GERD) with subglottic stenosis in adults and children. It is critical to treat LPRD after any type of airway reconstruction. Symptoms can be quantified by means of the Reflux Symptom Index, and findings can be assessed by the Reflux Finding P. Krishna Otolaryngology, Loma Linda Univ Health System, Loma Linda, CA, USA e-mail: [email protected] C. A. Rosen (*) UCSF Voice & Swallowing Center, Department of Otolaryngology-Head & Neck Surgery, University of California, San Francisco, San Francisco, CA, USA e-mail: [email protected]

Score. It is believed that both bile acids and pepsin contribute to the inflammation associated with LPRD and/or GERD. The gold standard in diagnosis remains the 24-h, multilevel (esophageal and pharyngeal) impedance pH testing. In this test, a reflux event is defined as a 5-s drop to below 4.0 of intraluminal pH levels. The addition of impedance testing to a pH probe study is the key to diagnosing nonacidic reflux. The standard of care for the treatment of LPR is usage of proton pump inhibitors (PPIs), which work to irreversibly inhibit the proton pumps of gastric parietal cells. Recent studies have shown that twice-a-day therapy appears to result in the highest symptom resolution. Most clinicians and studies support a duration of treatment of at least 4–6 months. It takes several months for the effects to be noted by the patient, so patients typically need encouragement to remain compliant with their medication for at least 2–3 months. Several controversies in the treatment of LPRD include the strength of association between cough and LPRD and duration of treatment. Long-term PPI use has its own side effects, potentially leading to an increased risk of hip fracture, chronic renal disease, community-acquired pneumonia, and dementia. An additional point of contention is the use of histamine H2 receptor antagonists (H2RAs) in combination with PPIs. A few studies have confirmed that H2RAs do not add any additional efficacy to treatment; however, many clinicians have noted a significant improvement in LPR control with H2RAs, especially when administered at night for the treatment of nocturnal acid breakthrough, and that the half-life of a “full dose of PPI” is approximately 18 h; thus, an H2RA can be used to theoretically achieve 24  h of acid reduction therapy. More detailed information on Laryngopharyngeal Reflux Disease can be found in Chapter 8—“Laryngopharyngeal Reflux Disease”.

7.3

Vocal Fold Granulomas

Vocal fold granulomas (specifically non-intubation-related) are notoriously recalcitrant to surgical therapy when the underlying causative factors (such as LPRD) are not con-

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trolled. Most vocal fold granulomas are located in the posterior third of the vocal folds either unilaterally or bilaterally. Postsurgical granulomas can occur anywhere that an ­operative site exists. LPRD may play an important role in the development of granulomata, as does phonotrauma and trauma secondary to endotracheal intubation. Intubation granulomas are more common in women, presumably because their smaller larynx is more prone to trauma from the endotracheal tube. One study found that of patients with vocal fold granulomas, up to 75% responded to clinical treatment with PPIs; however, 21% demonstrated recurrence. Microsurgical removal is rarely indicated; the indications and description of the technique is provided in Chapter 21—“Vocal Fold Granuloma.” The other treatment options for granulomas are voice therapy and a botulinum toxin type A (BTX-A) injection to the thyroarytenoid muscle. The latter causes temporary paresis of the vocal folds to reduce extensive interarytenoid contact. Vocal fold granulomas often also occur (and recur) due to an underlying glottic insufficiency. Excessive vocal fold closure pressure is applied to the arytenoids in an attempt to compensate for the glottic insufficiency, resulting in vocal fold granuloma formation or recurrence. Treatment of vocal fold granulomas due to glottic insufficiency involves vocal fold augmentation and/or medialization (see Chapter 30—“Vocal Fold Augmentation: Phonomicrosurgery,” Chapter 45—“Silastic Medialization Laryngoplasty for Unilateral Vocal Fold Paralysis,” and  Chapter 46—“GORE-TEX® Medialization Laryngoplasty”).

7.4 Infections and Inflammatory Disorders Acute laryngitis is an extremely common illness and is largely, though not always, viral in nature. Diagnosis is based on symptomatology, which includes hoarseness that may or may not have accompanied a viral prodrome consistent with an upper respiratory infection (URI). Several randomized trials have examined the impact of antibiotics on resolution of symptoms and have shown no significant change in objective outcomes, but there are some improvements in short-term subjective outcomes with regard to voice quality. Current data recommend no antibiotics be used and that simply supportive care (humidification, voice rest, hydration, and rest) be advocated. Any hoarseness lasting after 6  weeks, however, requires further evaluation. A brief course of corticosteroids can be highly beneficial when an earlier return to voice is needed. Fungal laryngitis is increasingly recognized as a cause of laryngitis. The widespread use of corticosteroid-based inhalers for the treatment of chronic obstructive pulmonary disease has been a major contributor to the increase in fungal laryngitis incidence. Fungal laryngitis may be mistaken for

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leukoplakia. A clinical appearance of whitish plaques surrounded by erythematous mucosa is characteristic. Predisposing factors apart from inhaler use include radiotherapy, prolonged antibiotic use, smoking, and immunosuppression. Dysphonia may occur in 5–50% of patients using inhaled steroids. There appears to be dose-dependent dysphonia in 34% of patients treated with beclomethasone dipropionate or budesonide when administered via pressurized, metered, dose inhalers. The most common organism implicated is Candida, but the presence of Aspergillus, Blastomyces, Histoplasma, and Coccidioides has also been documented in cases of fungal laryngitis. Diagnosis is based on demonstration of fungal spores, hyphae, and/or pseudohyphae within the upper epithelial layers of the laryngeal mucosa by culture or biopsy, both of which are performed via laryngoscopy or office endoscopy. However, often, the disease is treated clinically based on the characteristic findings. Inhalers used with a spacer decrease laryngeal deposition of the medication and can help in reduction or complete elimination of the offending agent. Further investigation regarding the role of the particle size of the inhaled medication on the larynx holds promise in reducing this condition. Treatment of fungal laryngitis rests on removal of the offending steroid when possible and antifungal medication. If the organism persists, then treatment with an per-oral (PO) ketoconazole agent for 3–4  weeks is commenced. Current standard of care, however, is use of an PO ketoconazole medication as the initial treatment, especially in an immunocompromised patient. Bacterial laryngitis is not frequently discussed but can be a source of dysphonia and is often overlooked. Recent studies have pointed to methicillin-resistant Staphylococcus aureus (MRSA) as the common etiology of bacterial laryngitis. Chemical laryngitis—specifically steroid inhaler (i.e., AdvairR) laryngitis—is another common cause of dysphonia in inhaler-using patients. Hoarseness is the most frequent local side effect of steroid inhalers. Several factors may contribute to this chemical irritation: the steroid, its preparation, the drug carrier, the type of inhaler device, mechanical irritation due to cough, inflammation of the upper airways, and surrounding irritating triggers such as smoke. One study noted the following mucosal changes in patients with inhaler-­ related dysphonia: vascular lesions such as dilated blood vessels, capillary ectasias and varices, and “areas of thickening, irregularity, and leukoplakia.” Often, use of the AdvairR inhaler can be stopped, and substitution therapy using two inhalers with the same drug composition as AdvairR can be administered until the laryngitis resolved. These changes appear to improve after cessation of the steroid inhaler. Some have attributed dysphonia secondary to steroid inhaler use to steroid myopathy, as both vocal folds appear atrophic and glottal closure is incomplete. The actual muscle bulk change

7  Nonsurgical Treatment of Voice Disorders

due to steroid inhalers is controversial and not supported by scientific evidence. Some findings can overlap with those of LPRD; therefore, LPRD should be optimally controlled in conjunction with reduction or discontinuation, when possible, of the inhaler. Idiopathic ulcerative laryngitis is a more recently recognized clinical entity. It typically occurs after an upper respiratory infection, but dysphonia and severe coughing lasts for more than 6 weeks, and it takes an average of 3 months for the symptoms to resolve. A laryngoscopic exam is marked by unilateral or bilateral mid-membranous vocal fold ulceration, and, if particularly severe, it can even be marked by granuloma development. Unfortunately, no pharmacological treatment has been found to hasten resolution of the disease as there is no one causative agent. Treatment of LPRD, however, is still recommended as is voice rest since ulcers occur in the striking zone of the vocal fold. In a small number of patients, the disease may be recurrent, suggesting a causative dormant infectious agent such as herpes simplex virus. Careful observation is required for this condition, and early biopsy should be avoided when possible. Autoimmune disorders are relatively rare, but several of these have effects on the vocal folds and subglottis. Rheumatoid arthritis (RA) affects 2–3% of the adult population, and 25–53% of patients have involvement of the larynx. The two main manifestations of RA at the level of the vocal folds are cricoarytenoid (CA) arthritis and rheumatoid lesions of the vocal folds, including “bamboo nodes.” Systemic treatment of RA is favored to treat rheumatoid and bamboo nodules. In addition, a localized injection of corticosteroid in the vocal folds may be helpful in the treatment of the lesions. If they persist and cause a functional voice problem, then endoscopic removal can be considered; also, this should be undertaken with great caution, as these lesions frequently involve the vocal ligament and their removal can result in a soft tissue deficit and significant postoperative scar formation. Vocal fold hypomobility associated with cricoarytenoid (CA) arthritis has resolved in some reports with systemic treatment and possibly steroid injection into or near the CA joint. Systemic lupus erythematosus (SLE) infrequently manifests itself in the larynx but can be associated with laryngeal edema in up to 28% of patients and with vocal cord paralysis in 11% of patients with SLE. Granulomatosis with polyangiitis ((GPA), formerly known as Wegener’s granulomatosis (WG)), is a relatively rare disease that principally involves three anatomical areas: the head and neck, the lower respiratory tract, and the renal system. The cause of GPA is unknown, but the disease is pathologically described by three findings: necrosis, granulomatous inflammation, and vasculitis. Signs associated with laryngeal involvement include wheezing or stridor, dyspnea, and dysphonia. Diagnosis is based on a blood test for the identification of antinuclear cytoplasmic antibody (ANCA), specifically

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c-ANCA, which is found in 90% or more of patients with active GPA. Subglottic stenosis is a major concern; the vocal folds proper are usually not involved. Systemic treatment includes use of corticosteroids and other immunosuppressive drugs, especially cyclophosphamide and rituximab. If the stenosis is critical, however, patients go on to either endoscopic or open surgical treatment, with or without tracheostomy depending on the severity of the disease (see Chapter 6—“Glottic and Subglottic Stenosis: Evaluation and Surgical Planning,” Chapter 34—“Subglottic/Tracheal Stenosis: Endoscopic Management,” Chapter 57—“Glottic and Subglottic Stenosis: Laryngotracheal Reconstruction with Grafting,” and Chapter 58—“Cricotracheal Resection with Primary Anastomosis”). The disease state should be under good medical control before performing surgical procedures for airway stenosis. Laryngeal amyloidosis is a rare and benign idiopathic disease, which presents as a primary disease or a secondary disease with other disease processes. It comprises 0.2–1.2% of all benign tumors. The disease is indolent and, when found in the larynx, can cause slowly progressive dysphonia and dyspnea; airway symptoms in general appear to predominate. When present in a secondary form, it can be associated with multiple myeloma, medullary thyroid carcinoma, and small cell carcinoma. Amyloid deposits or lesions are typically described as “firm, non-ulcerating, orange-yellow to gray epithelial nodules.” A definitive diagnosis is based on the histopathological presence of amyloid fibrils in a twisted β-pleated sheet pattern with affinity to Congo red dye. The underlying condition in the secondary form requires treatment; however, systemic treatment frequently may not eliminate the amyloid deposits. When the airway or voice is compromised, surgical intervention is warranted. Serial laser microlaryngoscopy excision is often effective at controlling symptoms. More advanced disease may require laryngofissure with partial or total laryngectomy. Primary (localized) and secondary (systemic) amyloidosis are distinguished based on physical exam (for tender bones, heart failure, hepatosplenomegaly, lymphadenopathy), blood/ serum and urine testing, chest and bone radiography, abdominal subcutaneous fat aspiration, computed tomography (CT) exam of suspicious parts of the body, and rectal biopsy.

7.5 Neurological Disorders 7.5.1 Laryngeal Dystonia (LD) (formerly known as spasmodic dysphonia) Laryngeal dystonia (LD) is a focal dystonia characterized by a vocal task-specific action or intention induced spasms. Dystonias, in general, are disorders of central motor

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p­ rocessing, and LD can be found in conjunction with other disorders, such as Meige’s syndrome, although it is typically isolated to the larynx. There are three classic types of LDs. Adductor SD (1) comprises 80% of patients with the disorder, abductor SD (2) constitutes patients with both adductor and abductor activity, and mixed LD (3) comprises the rest of the disease population. Adductor LD is marked by a “strained-strangled” speech pattern caused by premature and excessive glottic closure, whereas abductor LD is marked by breathy speech breaks and an overall hypophonia due to inappropriate glottic opening during speech. LD typically presents in female patients in their mid-30s, and, if it has been present for some time, many patients develop compensatory changes, which may mask the true diagnosis. Patients may not demonstrate speech breaks during singing or laughing tasks and find worsening of symptoms when under psychological stress. Diagnosis primarily rests on auditory-perceptual evaluation of connected speech supplemented by flexible nasopharyngolaryngeal examination. Diagnosis can be difficult, as patients may have associated essential tremor or actually have muscle tension dysphonia (MTD); both disorders can cause voice breaks. Few, if any, medications have been successful in ameliorating the symptoms of LD. Some patients find that alcohol or benzodiazepines are helpful in reducing the stress that may be the trigger for LD. The standard of care in the treatment of LD is injection of the affected muscle(s) with botulinum toxin type A (BTX-A), which causes a temporary chemical denervation of the thyroarytenoid–lateral cricoarytenoid muscle complex in adductor LD and the posterior cricoarytenoid muscle in abductor LD (see Chapter 39—“Botulinum Toxin Injection of the Larynx”). Prior to this, recurrent laryngeal nerve section was performed; however, recurrence of symptoms was typical (despite complete nerve section), and the overall voice quality worsened. Voice therapy can be used as an adjunctive therapy to treat compensatory behaviors or assist in differentiating LD from muscle tension dysphonia. Surgical treatments that heretofore have not been widely adopted include thyroarytenoid myomectomy, type II thyroplasty, and the selective laryngeal adductor denervation-reinnervation (SLAD-R) procedure. There is one long-term study of SLAD-R, which demonstrates that more than 90% of patients had favorable voice results with only 25% still exhibiting some evidence of voice breaks  (see Chapter 53—“Selective Laryngeal Adductor Denervation and Reinnervation”). A minority will experience recurrent symptoms.

7.5.2 Essential Tremor Essential tremor is the most common movement disorder, affecting 0.4–5.6% of those over the age of 40. However, the disease also appears to have a bimodal age distribution, with

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4.6–5.3% of cases occurring in the first two decades of life. There appears to be a familial association in 17–100% of individuals transmitted in an autosomal-dominant inheritance pattern with variable penetrance. Three areas of the body may be involved to varying degrees: the head, hands, and vocal tract. Essential tremor of the voice is seen in 12–30% of patients with essential tremor and a head tremor in 50%. Essential tremor of the voice is marked by a regular 4–12-kHz frequency oscillation of the affected muscles. Several drugs are associated with tremor production, and Parkinson’s disease (PD) is also considered in the differential diagnosis. Pharmacotherapy, specifically with primidone and propranolol, is employed as the first-line treatment but is more effective in treating limb-based tremor than in the vocal tract. Recently, some work has emerged concerning botulinum toxin A injections for treatment of essential  tremor  of the vocal tract. The difficulty with local treatment, however, is that multiple muscles may be involved in voice tremor (the soft palate, pharynx, and both intrinsic and extrinsic laryngeal musculature), so the benefit of a thyroarytenoid–lateral cricoarytenoid muscle complex injection is not nearly comparable to that of botulinum toxin A seen in LD treatment. Medically refractory cases are treated with thalamotomy or deep brain stimulation (DBS); bilateral thalamotomy is associated with significant vocal side effects such as hypophonia, and significant data for DBS in treatment of voice tremor are pending. However, some case reports indicate good control of vocal tremor with specific neurophysiological targeting of the ventral intermediate nucleus.

7.5.3 Parkinson’s Disease Parkinson’s disease (PD) affects nearly one million persons in the United States and, in severe forms, leads to considerable disability. The disease is caused by neurodegeneration within the nigrostriatal tracts of the basal ganglia, a neural center for motor control, which leads to decreased dopamine release. The hallmark clinical findings are bradykinesia, tremor, postural instability, and muscle rigidity. Phonatory effects include hypophonia, breathy dysphonia, and vocal tremor. The voice takes a monotonic quality. Many patients experience dysphagia and dysarthria. One study reported that 87% of PD patients demonstrated a physical exam finding of vocal fold bowing. The treatment of the voice component of PD involves a specialized voice therapy program, the Lee Silverman Voice Treatment (LSVT), with or without vocal fold augmentation to improve glottic configuration and closure. Typically, the LSVT alone is sufficient and vocal fold augmentation is not required. Treatment of PD is pharmacological, using dopamine agonists, and medically

7  Nonsurgical Treatment of Voice Disorders

r­ efractory cases may undergo DBS or pallidotomy. Currently, no data are available regarding the effect of DBS on the voice in PD, but anecdotal evidence suggests that it may have deleterious effects on voice and speech. There are also atypical parkinsonian syndromes such as progressive supranuclear palsy (PSP) and multiple system atrophy (MSA), which have additional clinical signs and widespread neuronal involvement. Early clinical signs overlap those of PD, thus making the diagnosis difficult. Patients with PSP and MSA display more pitch fluctuation, intensity variation, dysdiadochokinesia, harshness of voice, and inappropriate silences than do patients with PD. In short, patients with atypical parkinsonian syndromes have more spastic and ataxic components to their speech and voicing in addition to the hypokinetic characteristics of PD voicing.

7.5.4 Amyotrophic Lateral Sclerosis (ALS) Amyotrophic lateral sclerosis is a devastating progressive motor neuron disease involving both upper and lower motor neurons. It has features of upper motor neuron involvement, such as spasticity and hyperreflexia, and those of lower motor neuron involvement, including muscle atrophy, flaccidity, and fasciculations. Incidence is somewhere around 2 per 100,000 annually, and the average age of onset is the early sixties with a slight male preponderance. About 50% of patients complain of dysphonia characterized by a strained, rough voice. The most common findings on videostroboscopy include incomplete glottic closure, bowing of the vocal folds, hyperfunctional phonation, decreased abduction, mucous pooling, and pachyderma. Decreased vocal fold abduction can be severe enough to lead to sudden death in some patients with ALS. There is no cure for ALS; treatment is palliative.

7.5.5 Muscle Tension Dysphonia “Muscle tension dysphonia (MTD)” is a term used to describe voice disorders that are related to excessive and poorly regulated laryngeal muscle activity during speech. Many synonyms are used in clinical practice, and these include hyperfunctional dysphonia, muscle misuse, and tension-­fatigue syndrome to name a few. The “muscle tension” descriptor has been applied to muscle contraction patterns seen on flexible laryngoscopy of the endolarynx; these are classified from types I to IV, with type I being extremely mild constriction with an excessive posterior glottic chink to type IV being a concentric closure pattern of the supraglottis. Some of these patterns are seen in other disorders as well, such as adductor LD or even in normal voices, and these are not pathognomonic. There has not yet been validation of the

55

value from a prognosis nor treatment perspective of these types of MTDs. MTD can present as a primary problem often associated with post-URI onset, inappropriate pitch use, LPRD, stress reactivity, or significant voice demands. Modern-day, high-­ quality voice therapy is highly effective in treating primary muscle tension dysphonia. It can also present in a secondary form as compensation for glottic insufficiency. Circumlaryngeal massage has been used in conjunction with voice therapy to assist in reducing laryngeal height, as these patients frequently hold their larynges in an abnormally elevated position secondary to increased muscular tension. In the most severe or refractory patients, topical anesthetization of the endolarynx has assisted in decreasing laryngeal tension because of altered sensation and proprioception. “Functional dysphonia” or “aphonia” is a separate term that should be used for psychogenic dysphonia or conversion disorder. Those with conversion disorder experience significant psychological trauma from an event that causes the aphonia; as such, these patients require intense psychiatric treatment in addition to voice therapy. “Malingering” or “factitious dysphonia” would be included under this term. Some patients will develop “muscle tension aphonia” post-­ URI or noxious environment exposure and have no psychosocial etiology. This is considered to be an extreme variant of primary MTD.

7.5.6 Paradoxical Vocal Fold Motion Disorder/Inducible Laryngeal Obstruction Paradoxical vocal fold motion disorder (PVFMD) is a disorder marked by desynchronized or paradoxical adduction of the vocal folds during inspiration and/or expiration. As a result, the patient exhibits inspiratory stridor and/or experiences a sensation of airway restriction. This is often confused with the wheezing of asthma that, in contrast, occurs in the expiratory phase. Symptoms also include choking, aphonia or dysphonia, and chronic cough. Many terms have been used to describe this condition, including “vocal cord dysfunction,” “factitious asthma,” “psychogenic asthma,” “irritable larynx syndrome,” “Inducible Laryngeal Obstruction (ILO)”, and “episodic paroxysmal laryngospasm.” The differential diagnosis is bilateral vocal cord paralysis, hereditary abductor paralysis, posterior glottic stenosis, or cricoarytenoid joint fixation. PVFMD/ILO has many causes and has been classified into five organic and two nonorganic categories, based on its etiology. These include brainstem compression, severe cortical or upper motor neuron injury, nuclear or lower motor neuron injury, movement disorder, gastroesophageal reflux/LPRD, factitious or malingering PVFMD, and conversion disorder

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PVFMD.  PVFMD/ILO often occurs in primarily high-­ achieving, perfectionist adolescents who are usually athletes, as well as in young female professionals  (Excise-Induced laryngeal Obstruction). Patients complain of exercise-­ induced episodes of airway restriction, irritant-exposure triggers, or symptoms after a meal. Flow-volume loops have been used to assist in diagnosis; however, both false positives and false negatives are generated, and there is no consistent pattern. The gold standard in diagnosis is demonstration of PVFMD/ILO during flexible laryngoscopy, which may be seen at rest or after administration of a trigger (exercise, perfumes, etc.). Treatment consists of elimination or avoidance of triggers, including reflux and allergy treatment, and respiratory retraining therapy administered by a speech-language pathologist. Any coexisting asthma/reactive airway disease must also be aggressively treated. Occasionally, psychiatric treatment may also be required. Some have attempted use of heliox (80% helium and 20% oxygen) to decrease work of breathing, but the results have been mixed. Severe PVFMD/ ILO has been associated with neurological dystonia (respiratory dystonia) of the larynx and can be treated with BTX-A injections.

cific allergen. This process is associated with immunoglobulin E (IgE)-mediated anaphylaxis, but it is also seen in a non-IgE-mediated anaphylactoid response. Treatment of this disorder involves immediate airway control and injection of epinephrine with use of steroids and H2 blockers after the initial episode. More commonly, the larynx, specifically the vocal folds, can be affected by an allergic process of the unified airway causing significant dysphonia. Evaluation and treatment should be of the entire airway, especially the sinonasal airway. Many patients also suffer from chronic postnasal drip secondary to allergic rhinitis. These patients tend to frequently clear their throats, which leads to maladaptive laryngeal muscle usage and can lead to the development of vocal fold edema and/or lesions. Exposure and allergy to aerosolized irritants can also lead to muscle tension dysphonia. Mold and volatile organic compounds (VOCs) are the usual suspects. VOCs include alcohols, aldehydes, and ketones. Again, avoidance and/or removal of the source of the irritant are the mainstay of treatment. Immunotherapy is an important consideration for treatment of allergies affecting the larynx, as it avoids the drying effects of antihistamines in the endolarynx.

7.5.7 Post-viral Vagal Neuropathy (PVVN)

7.7 Medications and Their Effects on Voice

Post-viral vagal neuropathy (PVVN) is marked by chronic cough, with or without laryngospasm or PVFMD/ILO. The cough is considered to be a result of altered laryngeal sensitivity such as in post-viral neuralgias of other cranial nerves. The trigger may be an irritant or even palpation of the larynx. Laryngeal electromyography (EMG) is used to confirm neuropathic findings of the recurrent and/or superior laryngeal nerve. These patients are frequently treated for allergies, LPRD, and PVFMD and may be refractory to treatment. When faced with this situation, treatment with neuromodulator medications such as gabapentin, should be considered. Treatment success ranges from 37.5% to 80%. A starting dose of 100  mg three times a day is recommended, increasing to 300 mg three times a day for symptom control. Other medications such as amitriptyline, pregabalin, and tramadol have been used with reasonable success.

7.6 Allergy and Voice Disorders Allergic diseases can manifest in the larynx in several ways. The classic description is that of a laryngeal angioedema, an acute life-threatening process initiated by exposure to a spe-

Both allergy and post-URI patients can experience dysphonia related to persistent postnasal drip. Patients also experience cough due to direct irritation from mucus or because of altered sensitivity of the endolarynx. Severe coughing can result in phonotrauma, leading to vocal fold edema/ inflammation, vocal fold hemorrhage, and vocal fold lesion formation. As a result, many over-the-counter preparations are used for their antitussive and mucolytic properties. Guaifenesin is the most widely used expectorant and works best when the patient is well-hydrated. Codeine and dextromethorphan are added to many cold medicine preparations. Tramadol, which is a weak opiate, may have enhanced antitussive properties, without the significant opioid side effects associated with codeine. Antihistamines again should be used with caution in professional voice users with allergy, as the drying effects on the vocal folds can be detrimental. Leukotriene inhibitors, such as montelukast, and nasal corticosteroids can be used in allergic patients, with less drying. Despite widespread clinical use of oral corticosteroids for acute dysphonia in professional voice users, there is minimal scientific literature concerning this subject. The corticosteroid mechanism of action is to prevent capillary dilation and

7  Nonsurgical Treatment of Voice Disorders

decrease capillary permeability, which consequently decreases edema. Typically, oral steroids are used in short bursts, with a tapering dosage to avoid adrenocortical insufficiency and minimize long-term side effects. Intramuscular use is also reported for the acute situation. A few studies have shown improvement in objective acoustic measures with use of steroids. However, if used for a more extended period, then corticosteroids can lead to fluid imbalance, systemic muscle weakness and atrophy, gastrointestinal and neurological problems, glaucoma, electrolyte and metabolic disorders, and fungal infections. Corticosteroids have been linked to peptic ulcer development; therefore, any patient on long-term oral corticosteroids should be placed on at least one H2 blocker, preferably a PPI. Many medications have virilizing properties and should be used with great caution in professional voice users or any patient for that matter. These medications, such as Danazol, have been used for treatment of fibrocystic breast disease and endometriosis. Testosterone injections have been administered to women complaining of loss of libido or energy and have been reported in female athletes for enhanced performance. Non-phonatory side effects include acne, hirsutism, weight gain, and hairline recession. Voice effects include lowering of fundamental frequency, vocal instability with pitch breaks, loss of high-frequency vocal range, and generalized dysphonia. For Danazol, the incidence may be as high as 10% in patients on the medication. Although some reports have stated that the effects are temporary and discontinue the medication, there is potential for permanent voice change. This can be particularly damaging to voice professionals, so great caution must be exercised when considering prescribing these medications. During the premenstrual period of the menstrual cycle, many women exhibit pitch lowering secondary to presumed venous dilatation and edema of the vocal folds. Low-dose oral monophasic contraceptives have been shown to reduce this pitch variability and exhibit less androgenic side effects. One group of medications that should not be overlooked is herbal remedies. Many have anticoagulant properties and can predispose a person to vocal fold hemorrhage. These include dong quai, willow bark, primrose, garlic in high doses, vitamin E in high doses, gingko biloba, ginger, feverfew, and red root. Some may have cross-reactivity to ragweed: goldenseal, chamomile after long-term use, echinacea, St. John’s wort, yarrow, and dong quai. Some herbal medications may also have hormonal effects, e.g., dong quai may increase the effects of ovarian and testicular hormones. Yam has progesterone-like properties, and licorice root also has progesteronic in addition to estrogenic effects and can

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change vocal pitch. Primrose is a natural estrogen promoter, and melatonin in high doses acts as a contraceptive.

7.8 Vocal Hygiene A discussion of medical treatment of voice disorders would not be complete without discussing the importance of vocal hygiene. Elements of vocal hygiene include understanding that medical problems affect the voice, understanding the effects of smoking, alcohol, drugs, hydration and nutrition, vocal stress, and vocal exercise. Vocal hygiene involves knowledge, avoidance, or reduction of irritants such as gastric juices or tobacco smoke, dehydration, and control of postnasal drip of any cause. The patient should be made keenly aware of the danger of “singing sick,” as vocal injuries are more likely to occur in a sick singer than in a healthy one. The sick singer should take adequate vocal rest, fluids, and medical care as needed. Vocal fold hemorrhage and vocal fold lesions are the most significant concerns, and changing bad habits early in younger performers is critical to their long-term vocal health.

7.9 Role of the Speech-Language Pathologist in Voice Therapy A speech-language pathologist is instrumental in teaching the voice disorder patient about laryngeal anatomy and vocal biomechanics, which are central to the voice therapy process for many disorders. The speech-language pathologist, with special training in voice disorders, is an essential member of the diagnostic and therapeutic team required for high-quality voice care. The speech-language pathologist specializes in assessing and treating behavioral issues of the speaking and singing voice. Many patients with dysphonia struggle with a variety of poor behaviors and/or speaking techniques or inappropriate use of the voice, and these problems are all easily treated with the intervention of the speech-language pathologist, using the overall global term “voice therapy.” A detailed description of voice therapy treatment methods for a variety of dysphonias is outside the focus of this book, but it is essential component of the treatment of a wide variety of voice disorders is a nonsurgical approach to voice rehabilitation with voice therapy. Thus, the speech-language pathologist plays a crucial role in all phases of modern voice care (diagnostic, therapeutic, and rehabilitative).

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Key Points • A multitude of voice disorders, including LPR, vocal fold granulomas, acute laryngitis, fungal laryngitis, ulcerative laryngitis, and autoimmune laryngeal conditions, are appropriately managed primarily with medical treatment. • Corticosteroid inhalers are a common cause of dysphonia and can be due to chemical laryngitis from the irritative effect of the inhaler as well as opportunistic fungal infections of the larynx. • Neurological disorders involving the larynx are common and include laryngeal dystonia (formerly known as spasmodic dysphonia), essential tremor, Parkinson’s disease, ALS, and a multitude of other conditions. • Muscle tension dysphonia can be a primary condition or secondary—manifesting as a compensatory behavior for glottic insufficiency. Intervention with a speech-language pathologist is essential in the treatment of this condition and many other voice disorders. • Medications can have wide-ranging effects on the voice and must be considered as a primary or contributing cause of dysphonia.

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P. Krishna and C. A. Rosen Chhetri DK, Mendelsohn AH, Blumin JH, Berke GS. Long-term follow­up results of selective laryngeal adductor denervation-­reinnervation surgery for adductor spasmodic dysphonia. Laryngoscope. 2006;116:635–42. DelGaudio JM.  Steroid inhaler laryngitis: dysphonia caused by inhaled fluticasone therapy. Arch Otolaryngol Head Neck Surg. 2002;128:677–81. Devaney K, Ferlito A, Devaney SL, Hunter BC, Rinaldo A.  Clinicopathological consultation: Wegener’s granulomatosis of the head and neck. Ann Otol Rhinol Laryngol. 1998;107:439–45. Herridge MS, Pearson FG, Downey GP. Subglottic stenosis complicating Wegener’s granulomatosis: surgical repair as a viable treatment option. J Thorac Cardiovasc Surg. 1996;111:961–6. Ho AL, Erickson-DiRenzo E, Pendharkar AV, Sung CK, Halpern CH.  Deep brain stimulation for vocal tremor: a comprehensive, multidisciplinary methodology. Neurosurg Focus. 2015;38(6):1–8. Jaspersen D, Kulig M, Labenz J, et  al. Prevalence of extraesophageal manifestations in gastro-esophageal reflux disease: an analysis based on the Pro-GERD study. Aliment Pharmacol Ther. 2003;17:1515–20. Lee B, Woo P.  Chronic cough as a sign of laryngeal sensory neuropathy: diagnosis and treatment. Ann Otol Rhinol Laryngol. 2005;114:253–7. de Lima Pontes PA, De Biase NG, Gadelha ME.  Clinical evolution of laryngeal granulomas: treatment and prognosis. Laryngoscope. 1999;109(Pt. 1):289–94. Maschka D, Bauman NM, McCray PB, et al. A classification scheme for paradoxical vocal cord motion. Laryngoscope. 1997;107: 1429–35. Mehanna HM, Kuo T, Chaplin J, Taylor G, Morton RP.  Fungal laryngitis in immunocompetent patients. J Laryngol Otol. 2004;118: 379–81. Mirza N, Schwartz SK, Antin-Ozerkis DA.  Laryngeal findings in users of combination corticosteroid and bronchodilator therapy. Laryngoscope. 2004;114:1566–9. Mizoguchi K, Hatakeyama H, Yanagida S, Nishizawa N, Oridate N, Fukuda S, Homma A.  Perioperative complications and safety of type II thyroplasty (TPII) for adductor spasmodic dysphonia. Eur Arch Otorhinolaryngol. 2017;274:2215. Morrison M, Rammage L, Emami AJ. The irritable larynx syndrome. J Voice. 1999;13:447–55. Murry T, Rosen CA. Vocal education for the professional voice user and singer. Otolaryngol Clin N Am. 2000;33:967–81. Nanke Y, Kotake S, Yonemoto K, Hara M, Hasegawa M, Kamatani N.  Cricoarytenoid arthritis with rheumatoid arthritis and systemic lupus erythematosus. J Rheumatol. 2001;28:624–6. Park W, Hicks DM, Khandwala F, et al. Laryngopharyngeal reflux: prospective cohort study evaluating optimal dose of proton-pump inhibitor therapy and pretherapy predictors of response. Laryngoscope. 2005;115:1230–8. Reveiz L, Cardona AF.  Antibiotics for acute laryngitis in adults. Cochrane Database Syst Rev. 2015;23(5):CD004783. Roland NJ, Bhalla RK, Earis J. The local side effects of inhaled corticosteroids: current understanding and review of the literature. Chest. 2004;126:213–9. Roy N. Functional dysphonia. Curr Opin Otolaryngol Head Neck Surg. 2003;11:144–8. Rusz J, Bonnet C, Klempir J, et  al. Speech disorders reflect differing pathophysiology in Parkinson’s disease, progressive supranuclear palsy and multiple system atrophy. J Neurol. 2015;262: 992–1001.

7  Nonsurgical Treatment of Voice Disorders Schnoll-Sussman F, Katz PO.  Clinical implications of emerging data on the safety of proton pump inhibitors. Curr Treat Options Gastroenterol. 2017;15:1–9. Simpson CB, Sulica L, Postma GN, Rosen CA, Amin MR, Merati AL, et  al. Idiopathic ulcerative laryngitis. Laryngoscope. 2011;121:1023–6. Sinclair CF, Sulica L. Idiopathic ulcerative laryngitis causing midmembranous vocal fold granuloma. Laryngoscope. 2012;123:458–9. Stappaerts I, Van Laer C, Deschepper K, Van de Heyning P, Vermeire P.  Endoscopic management of severe subglottic stenosis in Wegener’s granulomatosis. Clin Rheumatol. 2000;19:315–7. Sulica L.  Contemporary management of spasmodic dysphonia. Curr Opin Otolaryngol Head Neck Surg. 2004;12:543–8. Sulica L.  Laryngeal thrush. Ann Otol Rhinol Laryngol. 2005;114:369–75. Sullivan KL, Hauser RA, Zesiewicz TA. Essential tremor: epidemiology, diagnosis, and treatment. Neurologist. 2003;10:250–8. Vaezi MF.  Gastroesophageal reflux disease and the larynx. J Clin Gastroenterol. 2003;36:198–203.

59 Van der Graaff MM, Grolman W, Westermann EJ, et al. Vocal cord dysfunction in amyotrophic lateral sclerosis: four cases and a review of the literature. Arch Neurol. 2009;66(11):1329–33. Walner DL, Stern Y, Gerber ME, Rudolph C, Baldwin CY, Cotton RT.  Gastroesophageal reflux in patients with subglottic stenosis. Arch Otolaryngol Head Neck Surg. 1998;124:551–5. Warrick P, Dromey C, Irish JC, Durkin L, Pakiam A, Lang A. Botulinum toxin for essential tremor of the voice with multiple anatomical sites of tremor: a crossover design study of unilateral versus bilateral injection. Laryngoscope. 2000;110:1366–74. Watts CR, Early SE.  Corticosteroids: effects on voice. Curr Opin Otolaryngol Head Neck Surg. 2002;10:168–72. Woo P.  Carbon dioxide laser-assisted thyroarytenoid myomectomy. Lasers Surg Med. 1990;10(5):438–43. Woo P, Mendelsohn J, Humphrey D. Rheumatoid nodules of the larynx. Ear Nose Throat J. 1995;113:147–50. Zesiewicz TA, Elble R, Louis ED, et al. Practice parameter: therapies for essential tremor. Neurology. 2005;53:2008–20.

8

Laryngopharyngeal Reflux Disease Thomas L. Carroll and Matthew R. Naunheim

8.1

Fundamental and Related Chapters

Please see Chapter 2—“Principles of Clinical Evaluation for Voice Disorders”, Chapter 4—“Pathological Conditions of the Vocal Fold”, Chapter 7—“Nonsurgical Treatment of Voice Disorders”, and Chapter 22—“Vocal Fold Leukoplakia and Epithelial Dysplasia: Phonomicrosurgery”, for further information.

8.2

Disease Characteristics

Laryngopharyngeal reflux disease (LPRD) is the chronic reflux of gastric contents into the upper aerodigestive tract. Its mechanism of action is the retrograde flow of stomach acids, pepsin, and bile past the upper esophageal sphincter (UES) into the pharynx and larynx, which results in a local inflammatory process. LPRD can be coexistent with gastroesophageal reflux disease (GERD), though it often occurs without frank GERD symptoms. Symptoms of LPRD can include all or some of the following: chronic cough, dysphagia, throat clearing, mucus sensation, globus sensation, laryngospasm, disordered laryngeal breathing, and dysphonia. Patients often describe worse symptoms in the morning that can improve as the day goes on, sometimes with a relapse later in the day. Often, these symptoms are vague and have significant overlap with other conditions, including allergic disease and vocal fold atrophy. Postnasal drip (PND), in the setting of a normal endonasal exam, and lack of allergic symptoms are often attributable to T. L. Carroll (*) Otolaryngology—Head and Neck Surgery, Department of Surgery, Brigham and Women’s Hospital, Boston, MA, USA e-mail: [email protected] M. R. Naunheim Department of Otolaryngology—Head and Neck Surgery, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, MA, USA e-mail: [email protected]

LPRD rather than allergy (one should specifically inquire about itchy/watery eyes, runny nose, sneezing, and other atopic symptoms before making this assumption). Although chronic exposure of the stomach contents (acids) to the mucosa of the laryngopharynx can directly contribute to LPRD, nonacidic refluxate components may play a more important role than previously realized. Most patients with LPRD do not have an acidic brash or bitter taste as is seen in GERD. Pepsin, a digestive enzyme activated by stomach acids to break down proteins into polypeptides, is a component of gastric refluxate and has been shown in in vitro models to produce inflammatory cytokines in pharyngeal mucosal cell lines at neutral pH. Therefore, even when acids are pharmacologically neutralized, nonacidic or weakly acidic reflux events may still cause inflammation and should be considered a target for treatment in LPRD. Additionally, the number of reflux events in a person remains the same despite acid suppression. When treating patients with presumed LPRD, successful progression through various diagnostic and treatment choices will be easier if acids are conceptualized as a cofactor of pepsin activation rather than the primary insult in the LPRD inflammatory process. Chronic LPRD can have a damaging effect on the laryngopharyngeal mucosa with evidence that pepsin contributes to malignant transformation. More common, and often less considered in an LPRD patient without GERD symptoms, are the risks to developing Barrett’s esophagus, which could lead to adenocarcinoma of the esophagus. Thus, screening of the distal esophagus is a consideration in patients with LPRD.

8.3

Diagnosis

History is the most important factor in diagnosing LPRD in most patients, but findings on laryngeal examination, although often correlative to the history, are sometimes accepted as being diagnostic on their own. Laryngeal findings attributed to LPRD classically include pachydermia (heaped up mucosa on the endolaryngeal surface of the inter-

© Springer Nature Switzerland AG 2024 C. A. Rosen, C. B. Simpson, Operative Techniques in Laryngology, https://doi.org/10.1007/978-3-031-34354-4_8

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arytenoid mucosa), pseudosulcus (infraglottic edema), edema of the post-cricoid area, and erythema/prominent vascular striping of the arytenoids (Fig. 8.1). LPRD-related conditions may also be seen during flexible laryngoscopy. These include vocal process granulomas (VPGs), subglottic stenosis, and generalized edema and erythema of the larynx. Keratotic lesions of the vocal folds and vocal fold carcinomas have been associated with LPRD, but no direct link has yet been established. Stroboscopy plays an important role in diagnosing other pathologies that can cause dysphonia or other throat symptoms and should not be routinely excluded in the face of a symptom that is classically attributed to LPRD. For example, glottic insufficiency (GI) and VPGs can cause LPRD-like symptoms in the absence of dysphonia. A combination of glottic insufficiency (GI) and LPRD is often the root cause of non-intubation-related VPGs. A gross VPG would be seen without stroboscopy; however, subtle GI may be missed without stroboscopy. Treatment options (such as injection augmentation (Chapter 21—“Vocal Fold Granuloma”), if voice therapy fails) could be missed. Two common options for a more definitive diagnosis are empiric medical therapy and objective reflux testing. Two other common tests often discussed as part of the suspected LPRD patient picture, namely, barium swallow and upper GI endoscopy, do not diagnose LPRD. Many patients are seen to have reflux on barium swallow, but the test only demonstrates a short segment of time and the presence of reflux, even proximal esophageal reflux, may be normal. Not all LPRD patients have esophageal changes on upper endoscopy. Although esophageal endoscopy is beneficial to rule out esophageal mucosal disease, it should not translate into the assumption that LPRD is unrelated to the patient’s symptoms. Currently, the decision to treat empirically or engage

in further testing depends on the physician’s practice patterns and the patient’s preference.

8.3.1 Empiric Medical Therapy Many practitioners advocate for empiric medical therapy using PPIs (Fig. 8.2). Empiric medical therapy is “successful” in up to 74% of suspected LPRD patients. Empiric treatment traditionally has consisted of a twice daily (bid) PPI (e.g., omeprazole 40 mg, twice daily) with or without an H2 blocker (e.g., famotidine 40  mg at bedtime (qhs)) for 3 months. An alternate dosing scheme that has been shown to be effective in two-thirds of patients, who ultimately would respond to acid suppressant therapy alone, is once daily 40-mg omeprazole or equivalent and a bedtime dose of 40-­ mg famotidine (qd/qhs dosing). Patients who experience zero or little improvement of symptoms on omeprazole 20-mg bid or qd/qhs dosing are increased to a 40-mg bid dosing. The mistake made by clinicians for a patient who has failed high-dose bid PPI dosing is then assuming that the patient does not have reflux. Approximately 36% of patients who fail empiric therapy may still have LPRD that would never have responded to acid suppression. Thus, and most

Suspected LPR

Empiric Treatment QD/QHS Treatment Success*

Treatment Failure

Connue for 6 Months Total

Increase to BID, stop QHS

Taper

Treatment Success*

Connue for 6 months total

Treatment Failure**

MII/HREM ON BID

Taper

Fig. 8.1  Pachydermia and edema of the post-cricoid area and arytenoids characteristic of LPR

Fig. 8.2  An algorithm for empiric treatment of LPR. * Treatment Success represents patients who respond to treatment. **Treatment Failure represents nonresponders. MII full column pH impedance with dual pH probes, HREM high-resolution esophageal manometry, qd/qhs 40 mg omeprazole or equivalent taken 30 min before breakfast/40 mg famotidine at bedtime or equivalent, bid 40 mg twice daily omeprazole or equivalent taken 30 min prior to breakfast and dinner

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important to understand, “treatment failure with empiric PPIs does not rule out reflux.” Patients who fail high-dose bid PPIs, those who cannot tolerate them, and those who refuse empiric PPI trials in the face of suspected LPRD should be offered objective reflux testing or at a minimum a trial that includes alginate formulations after meals and before bed. Additionally, although empiric therapy is the predominant practice pattern among otolaryngologists, it should be noted that gastroenterologists are against the use of empiric treatments for LPRD unless it is coexistent with GERD symptoms. However, the American College of Gastroenterology does support the use of reflux testing for atypical reflux symptoms (i.e., LPRD symptoms) when the patient does not present with the typical GERD symptoms.

8.3.2 Objective Testing Objective tests include pH monitoring with esophageal and pharyngeal probes, multichannel intraluminal impendence (MII) testing, and high-resolution manometry (HRM). These can be used in an up-front manner or as follow-up testing for patients who fail empiric therapy (Fig. 8.3).

8.3.2.1 pH-Only Testing Previously considered the “gold standard” for esophageal reflux testing, dual pH probe monitoring typically consists of Fig. 8.3  An algorithm for up-front testing. MII full column pH impedance with dual pH probes, HREM high-resolution esophageal manometry

placement of a transnasal catheter with two pH sensors: one 5  cm above the lower esophageal sphincter (LES) and the other in the upper esophagus or hypopharynx. This sensor is left in place for 24 h, and events of pH change are recorded on a wearable monitoring device. Patients can report “events” on the monitoring device when they feel their reflux-related symptoms, and a correlation can be made between what the patient feels and what is happening (“Reflux Symptom Index” or “reflux symptom correlation” score). The upper pH sensor is prone to drying if placed in the pharynx, which may result in incomplete data. An older catheter type with a single distal pH probe is less commonly employed due to the limited data acquired. For those who cannot tolerate a transnasal catheter or need more than 24 h of data, a capsule pH meter is available (Bravo™, Medtronic, Minneapolis, MN). This device, placed during upper endoscopy, attaches to the luminal mucosa of the esophagus 5  cm above the LES.  This will typically transmit 48–72  h of data through a frequency modulation (FM) transmitter to a belt-­worn monitor before the probe sloughs off and the device passes through the bowel. Capsule pH meters only detect acidic events and can afford the patient the ability to report symptoms when they occur. An oropharyngeal probe (Restech Dx-pH System, Restech Technology Corporation, Houston, TX) is commonly offered by otolaryngologists because it is inexpensive, easy to place, and easy to score the test results. It is

Suspected LPR:

MII/HREM

Negave (normal MII and HREM)

Dysmolity (abnormal HREM)

Acid Reflux (abnormal MII)

GI referral

Start PPI regimen

Further symptom workup

Taper if possible

Non-Acid Reflux (abnormal MII)

Alternave therapies (alginate, an-reflux surgery)

Treatment success

Treatment failure

Connue 6 months

Alternave therapies (alginate, an-reflux surgery)

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T. L. Carroll and M. R. Naunheim

marketed as a device that records changes in oropharyngeal pH due to reflux events. This, however, is unlikely the case as simultaneous esophageal impedance and oropharyngeal pH monitoring has debunked the myth that the pH change detected by the oropharyngeal pH sensor is directly from reflux events. The oropharyngeal probe does have some benefits that other pH-only tests cannot demonstrate. The probe itself resists drying and detects changes in pH levels that approach neutral as opposed to pH 95%. Success is defined as an improvement in voice quality and function. It is important for the surgeon to make the distinction between voice improvement and restoration to the patient’s premorbid vocal capabilities. The success rate to achieve the latter goal is going to be lower and will be directly related to the pathology of the vocal folds, ability/training of the patient, and vocal demands. It is important to inform the patient that there is a risk of postoperative scarring and permanent postoperative dysphonia that could even worsen his/her condition compared to the preoperative status. This risk is quite small (1–2%), and, similarly, there is a risk that significant improvement in vocal function will not be obtained despite the surgeon’s and the patient’s best efforts (1–2% incidence of “no improvement”). Appropriate informed consent for “phonosurgeries involving patients with glottic incompetence” should involve specific expectations, voice improvements, and persistent limitations after surgery. Typically, these types of surgical procedures have an extremely high degree of success with respect to increasing volume, clarity, and endurance with normal speaking-voice use and normal speaking demands. There are often limitations after this type of surgery that persist, involving loud speech and/or singing. These limitations exist because of the persistent underlying pathological condition such as vocal fold paralysis, vocal fold scarring, and vocal fold paresis. Informed consent for surgical removal of “laryngeal cancer” should include reduction of vocal and swallowing function as well as the risk for additional surgery depending on permanent pathology results after surgery. Informed consent for “airway procedures” must involve a discussion that as the surgical procedure obtains an increased airway for the patient, the greater the likelihood of diminution of

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the patient’s vocal function. The goal of the surgery is to obtain an adequate airway while at the same time minimizing the negative impact on the voice. Due to this voice vs airway equation and the need for conservative glottic enlargement, the patient should be informed of the likelihood of the need for repeat surgery. Patients with airway problems preoperatively, that have not undergone a tracheotomy, should also consent for a possible tracheotomy depending on a variety of intraoperative situations. Key Points • Most phonosurgical procedures are elective, and, thus, the decision to proceed with surgery should be patient-driven. The surgeon serves as educator so that realistic goals of postoperative voice quality and function are clearly understood. • The key principle of decision-making with respect to phonomicrosurgery is the use of nonsurgical rehabilitative treatment options (when appropriate) prior to proceeding with surgery. • With respect to microsurgery for benign lesions of the lamina propria, the most important question that must be answered before deciding for or against proceeding with phonomicrosurgery is: “Can the patient do what they need to do with his/her voice after undergoing maximum of nonsurgical rehabilitation?” • The informed consent process for phonomicrosurgery should be individualized due to the specific pathological condition present and the surgical approach recommended.

C. A. Rosen and C. B. Simpson

Bibliography Akbulut S, Gartner-Schmidt JL, Gillespie AI, Young VN, Smith LJ, Rosen CA.  Voice outcomes following treatment of benign midmembranous vocal fold lesions using a nomenclature paradigm. Laryngoscope. 2016;126(2):415–20. Bouchayer M, Cornut G.  Microsurgical treatment of benign vocal fold lesions: indications, technique, results. Folia Phoniatr. 1992;44:155–84. Courey MS, Gardner GM, Stone RE, Ossoff RH.  Endoscopic vocal fold microflap: a three-year experience. Ann Otol Rhino Laryngol. 1995;104(Pt. 1):267–73. Dejonckere PH, Committee on Phoniatrics of the European Laryngological Society. Assessing efficacy of voice treatments: a guideline. Rev Laryngol Otol Rhinol. 2000;121:307–10. Ford CN.  G. Paul Moore lecture: lessons in phonosurgery. J Voice. 2004;18:534–44. Hess MM, Fleischer S.  Laryngeal framework surgery: current strategies. Curr Opin Otolaryngol Head Neck Surg. 2016;24(6):505–9. Netterville JL, Stone RE, Luken ES, Civantos FJ.  Silastic medialization and arytenoid adduction: the Vanderbilt experience. A review of 116 phonosurgical procedures. Ann Otol Rhino Laryngol. 1993;102:413–24. Zeitels SM, Hillman RE, Desloge R, Mauri M, Doyle PB. Phonomicrosurgery in singers and performing artists: treatment outcomes, management theories, and future directions. Ann Otol Rhino Laryngol. 2002;190(Suppl):21–40.

Anesthesia and Airway Management for Laryngeal Surgery: Surgeon’s Perspective

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Karen J. Maresch, Clark A. Rosen, and C. Blake Simpson

10.1

Fundamental and Related Chapters

Please see Chapter 11—“Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective”, Chapter 16—“Principles of Laser Microlaryngoscopy”, Chapter 32—“Bilateral Vocal Fold Paralysis”, Chapter 33—“Posterior Glottic Stenosis: Endoscopic Approach”, Chapter 34—“Subglottic/Tracheal Stenosis: Endoscopic Management”, Chapter 46—“GORE-TEX® Medialization Laryngoplasty”, Chapter 47—“Arytenoid Adduction”, Chapter 57—“Glottic and Subglottic Stenosis: Laryngotracheal Reconstruction with Grafting”, Chapter 58—“Cricotracheal Resection with Primary Anastomosis”, and Chapter 59—“Tracheal Stenosis: Tracheal Resection with Primary Anastomosis” for further information. A laryngeal surgeon needs to have detailed knowledge of the various aspects of anesthesia due to the requirement of close, coordinated care in many laryngeal surgeries. This chapter and Chapter 11—“Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective” provide a diverse range of information that will assist the laryngeal surgeon and anesthesiologist in providing optimal care for individuals undergoing laryngeal surgery. It is helpful to have both chapters available while studying these chapters, as they share many of the same figures.

K. J. Maresch (*) Department of Anesthesiology, University of Pittsburgh Medical Center, Pittsburgh, PA, USA e-mail: [email protected] C. A. Rosen UCSF Voice & Swallowing Center, Department of Otolaryngology-Head & Neck Surgery, University of California, San Francisco, San Francisco, CA, USA e-mail: [email protected] C. B. Simpson Department of Otolaryngology—Head and Neck Surgery, University of Alabama at Birmingham, Birmingham, AL, USA e-mail: [email protected]

10.2

Equipment

Airway management requires the following: 1. Large-bore laryngoscopes Examples include: (a) See Chapter 12—“Principles of Phonomicrosurgery” (b) An “anterior commissure” laryngoscope made by several companies 2. Ventilating laryngoscopes with jet ventilation compatibilities (a) An Ossoff-Pilling (OP) laryngoscope (Teleflex, Morrisville, NC) (b) A pilling subglottiscope (male + female) (Teleflex, Morrisville, NC) (c) A Garrett-modified Ossoff-Pilling laryngoscope (Teleflex, Morrisville, NC) 3. A microlaryngeal endotracheal tube (ETT) (a) A 5.0/5.5 or smaller ETT (see Chapter 11—“Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective”, Fig. 11.4) 4. A laser-safe ETT (a) A 5.0/5.5 or samller ETT (see Chapter 11—“Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective”, Fig. 11.5) (TenaxTM, Bryan Medical, Cincinnati, OH) 5. Jet ventilator devices (a) A manual, handheld ventilator (b) An automatic high-frequency ventilator (Acutronic Monsoon III, Acutronic Medical Systems, Hirzel, Switzerland) (see Chapter 11—“Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective”, Fig. 11.8) 6. Jet ventilation conduits (a) A Hunsaker Mon-Jet tube (Medtronic, Minneapolis, MN) (see Chapter 11—“Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective”, Fig. 11.7) (b) A jet venturi needle 7. Tracheostomy tubes and a surgical tray

© Springer Nature Switzerland AG 2024 C. A. Rosen, C. B. Simpson, Operative Techniques in Laryngology, https://doi.org/10.1007/978-3-031-34354-4_10

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8. Topical laryngotracheal anesthesia (LTA) (a) 4% Lidocaine 4 ml LTA prepackaged kits (b) 1, 2, or 4% lidocaine (maximum cumulative dose 5 mg/kg) with a laryngeal cannula

2. It is prudent for the surgeon to personally perform a physical assessment of each patient’s airway in the preoperative area to identify predictors of difficult laryngoscopy or intubation (see Sect. 10.4.2). Identifying a potentially challenging laryngoscopy will allow for the preparation and availability of additional equipment to aid in a diffi10.3 Team Approach to Patient cult laryngeal exposure. Management 3. Any patient who is not deemed suitable by the anesthesia team for standard intubation with direct laryngoscopy Collaboration of surgeons with their anesthesia colleagues is (DL) is a red flag for surgical laryngoscopy. A team disone of the most important and often neglected aspects of a cussion of the airway assessment and reasons for altersuccessful laryngeal surgery. Lack of preoperative planning nate airway management plans is warranted. between the surgical and anesthesia teams can turn an other- 4. Although conscientious laryngologists are present for all wise simple microlaryngoscopy case into a chaotic, life-­ laryngeal instrumentation of their operative patients, threatening airway crisis. potentially difficult intubations require not only surgeon The following principles should be observed: presence but also vigilance during induction and plans to assist in securing the airway if necessary. 1. In routine cases with no anticipated airway issues, the 5. In case of a higher likelihood of difficult intubation, patients anesthesia team can proceed with a standard intravenous should be informed about the plan to convert to an awake induction followed by routine intubation. intubation or a tracheostomy and their consent should be 2. In difficult or unknown airway situations, a team approach (airobtained preoperatively. This may help an unexpectedly way huddle) to initial airway management is required. awakened patient cooperate with further procedures. 3. All patients should be assessed for predictors of difficult laryngoscopy or intubation (see Sect. 10.4.2). 4. If there are space-occupying lesions, such as large polyps 10.4.2 Preoperative Airway Evaluation or laryngeal stenosis that may impede laryngoscopy or ETT insertion, then preoperative videos should be Preoperative evaluation of the airway includes 11 assessment reviewed by the surgical and anesthesia teams prior to the points from the upper incisors to the larynx. These predict surgery. the Cormack–Lehane laryngoscopic view, which classifies 5. A primary management plan along with several alternate the view obtained by direct laryngoscopy based on the strucoptions should be discussed and agreed upon by all mem- tures seen: bers of the team. Operating room (OR) personnel such as the circulating nurse and scrub technician should also be included in this discussion as they are integral to the • Grade 1: Full view of the glottis, including the antesmooth management of a difficult airway. rior commissure 6. All routine and emergency airway equipment should be • Grade 2a: Partial view of the glottis immediately available and functional (see Sect. 10.2). • Grade 2b: Partial view of the posterior commissure Emergency airway management, whether planned or or arytenoids unexpected, should be automatic and algorithmic, as • Grade 3: Only the epiglottis opposed to chaotic and reactive. • Grade 4: No view of the glottis or epiglottis

10.4 Preoperative Preparation 10.4.1 Key Principles The key principles of preoperative preparation include: 1. Microlaryngoscopy patients should receive standard preoperative care (see Chapter 11—“Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective”, Sect. 11.3.2), including glycopyrrolate 0.2  mg intravenous (IV) to decrease airway secretions and improve visualization.

The visual airway exam focuses on four areas: the teeth, pharynx, mandibular space, and neck. It assesses the likelihood of aligning the oral, pharyngeal, and laryngeal axes to obtain an instrumentable glottic view (see Chapter 11—“Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective”, Fig. 11.1). 1. Teeth (a) Length of the upper incisors • Long incisors limit the ability to lift up the proximal end of the laryngoscope.

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• This is assessed by having the patient insert two of their knuckles between their incisors. • MAC and Miller laryngoscopes require a minimum of 3-cm inter-incisor distance to insert a blade into the mouth. • A less than 3-cm opening requires consideration of alternatives to DL intubation and/or smaller peroral instrumentation equipment. 2. Pharynx (a) The Mallampati (MP) score • This assesses tongue size in relation to the oropharynx based on structures visualized with maximal mouth opening (Fig. 10.1). • A large tongue is more difficult to displace with a laryngoscope. • This mainly assesses anterior–posterior (A-P) oropharyngeal volume.

• • • •

Fig. 10.1  The Mallampati score assesses tongue size in relation to the oropharynx based on structures visualized with maximal mouth opening. (Reprinted with permission of Springer Nature from Irefin S, Kopyeva T. Perioperative Airway Management. In: Sikka PK, Beaman ST, Street JA, eds. Basic Clinical Anesthesia. New  York: Springer-­ Verlag; 2015)

• It creates an unequal position of the fulcrum and decreased movement at the distal end of the laryngoscope. (b) Overriding upper incisors or “overbite” • This forces the laryngoscope blade to enter the mouth in the cephalad direction. (c) Temporal mandibular joint (TMJ) mobility • The ability to bring the mandibular teeth in front of the maxillary teeth by biting the upper lip with the lower teeth is assessed. • Good mobility indicates that the mandible and tongue will displace anteriorly with the laryngoscope improving the alignment of the axes. (d) Mouth opening • This is ideally 5–6  cm (approximately 2–3 fingerbreadths).

MP 1: Soft palate, uvula, and pillars MP 2: Soft palate and most of the uvula MP 3: Soft palate with/without the base of the uvula MP 4: Hard palate only

(b) Palate shape • This mainly assesses lateral oropharyngeal volume. • A high or narrow arched palate does not allow room for an ETT to lie beside the laryngoscope in the oropharynx such that the ETT insertion obscures the glottic view and increases the risk of esophageal intubation. • This may impact the choice of surgical laryngoscope and make manipulating the scope around the ETT in the oral cavity difficult. 3. Mandibular space (a) Thyromental distance (TMD) • An optimal TMD is >6  cm or approximately 3 fingerbreadths. • An optimal TMD likely indicates a straight line from the upper incisors to the larynx. • TMD indicates whether the mandibular space is available to allow anterior displacement of the tongue. • This indicates the likelihood of the anteriorly positioned larynx relative to other upper airway structures.

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Fig. 10.2  An illustration of anatomic features in a patient with an anticipated, difficult glottic view

(b) Mandibular space compliance • Compliant space allows easier displacement of the tongue. • Previous radiation raises concerns of fibrosis and decreased tissue compliance. • This may be decreased with infection, inflammation, masses, or hematoma. 4. Neck (a) Short neck • This is characterized by a shorter longitudinal distance with a more acute curve from the upper incisors to the larynx (Fig. 10.2). (b) Thick neck • This is not an independent risk factor for a poor glottic view. This is associated with a short neck and a higher MP score. (c) Cervical spine range of motion • This assesses the ability to flex and extend the head and neck. • Here, the patient assumes a sniffing position with the chin flexed on the neck and the head extended at the atlanto-occipital joint. • Existing cervical spine disease, previous surgeries, fusions, or osteoarthritis are considered. Favorable 11-point assessment: • Normal upper incisor length • Normal bite indicated by meeting of the first molars • Able to bite the upper lip with the lower teeth • Able to insert two knuckles between the incisors (5–6-cm opening) • Uvula visible on MP exam • Normal shape and width of the palate • TMD > 6 cm or 3 fingerbreadths • No concerns with mandibular tissue compliance

• Appropriate neck length for patient’s height • No concerns with neck thickness • Full cervical spine range of motion

10.5 Initial Airway Management 10.5.1 Intubation Options Microlaryngoscopy generally employs one of the following methods for establishing and maintaining an airway: 1. Oral intubation (a) 5.0 or 5.5 microlaryngeal ETTs (MLTs) (Medtronic, Minneapolis, MN). MLTs have an extended length to allow small-diameter ETTs to adequately span the distance between the oral commissure and mid-­ trachea (see Chapter 11—“Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective”, Fig. 11.4). (b) Laser-resistant ETT (see Chapter 11—“Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective”, Fig. 11.5) in all cases in which a surgical laser will be used, with the exception of ventilation through the laryngoscope with no ETT in place. The laser-resistant ETT chosen needs to be approved for use with the specified laser (potassium–titanyl–phosphate (KTP), CO2, neodymium-­ doped yttrium aluminum garnet (Nd/YAG)) as indicated in the manufacturer’s guidelines (see Sect. 10.7.1) (TenaxTM, Bryan Medical, Cincinnati, OH) 2. Jet ventilation using the following: (a) A laryngoscope with a ventilating cannula (see Chapter 11—“Anesthesia and Airway Management

10  Anesthesia and Airway Management for Laryngeal Surgery: Surgeon’s Perspective

for Laryngeal Surgery: Anesthesia’s Perspective”, Fig. 11.6) (b) A jet venturi needle attached to the laryngoscope (c) A Hunsaker Mon-Jet tube (Medtronic, Minneapolis, MN) (see Chapter 11—“Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective”, Fig. 11.7) 3. Preexisting tracheostomy allowing stomal intubation (a) A cuffed tracheostomy tube (b) A cuffed ETT of an appropriate size to allow stomal insertion (c) A laser-resistant ETT of an appropriate size to allow stomal insertion (see Sect. 10.7)

10.5.2 Laryngeal Factors Impacting Airway Management The location of a laryngeal lesion will be a factor in the method chosen to establish and maintain the airway. For example, 1. Lesions located in the anterior two-thirds of the membranous vocal folds (a) A 5.0 or 5.5. ETT generally allows adequate exposure and treatment. 2. Lesions on the posterior third of the larynx, vocal process, posterior commissure, and arytenoid region (a) An anteriorly displaced ETT (b) Intermittent apnea (see Sect. 10.6.3) (c) Require high-frequency jet ventilation (HFJV) • Through a laryngoscope • Through a subglottic catheter (Husaker tube)

10.5.3 Patient Positioning for Laryngoscopy For optimal laryngoscopic exposure, the following guidelines are followed: 1. Patients are positioned in a Boyce Jackson or classic sniffing position with the tragus of the ear aligned with the sternal notch (see Chapter 11—“Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective”, Fig. 11.2). 2. In a patient of normal size, the head is extended at the atlanto-occipital joint and the neck flexed along the cervicothoracic vertebrae (see Chapter 11—“Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective”, Fig. 11.1). 3. Obese patients may require ramping to achieve this position with blankets placed under their upper back and head along with a donut-shaped head stabilizer (see Chapter 11—“Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective”, Fig. 11.2). A special

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positioning pillow may also be used such as the Troop Elevation Pillow (Mercury Medical, Clearwater, FL) (see Chapter 11—“Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective”, Fig. 11.2).

10.5.4 Principles of Establishing the Airway In addition to the usual laryngoscopy tools, emergency airway equipment should be readily available, even in patients for whom routine, easy airway instrumentation is expected.

10.5.4.1 Anticipated Easily Instrumented Airway 1. Optimal patient positioning is verified. 2. Arterial oxygen saturation (SaO2) is maximally increased by pre-oxygenating with 100% O2 through a well-fitting mask. 3. A short-acting induction agent such as propofol is administered. 4. Immediately after loss of the lash reflex, the ability to ventilate the uninstrumented airway, with/without oral/ nasal airways, is verified. 5. If the patient is easily ventilated, then an appropriate dose of paralytic is administered and time allowed for effectiveness. 6. Direct laryngoscopy and insertion of an MLT or an appropriate endotracheal tube is completed. (a) Topical lidocaine laryngotracheal anesthesia (LTA) is sprayed immediately prior to ETT insertion. This may reduce laryngeal sensation and laryngospasm. (b) If a reasonable amount of time has elapsed, then a second LTA may be administered at case completion prior to removal of the laryngoscope. To prevent toxicity in short cases or low-weight patients, the total lidocaine dose must be considered. Care must be taken by the surgeon to avoid suctioning the airway and removing the LTA lidocaine after it has been administered. 7. ETT position is verified through end-tidal carbon dioxide (EtCO2) and audible bilateral breath sounds on auscultation.

10.5.4.2 Anticipated or Known Difficult Airway Multiple factors may predict a difficult laryngoscopy or intubation (see Sect. 10.4.2). In some patients, despite the likelihood of poor intubating conditions, the surgeon may choose to assess laryngeal exposure under general anesthesia with direct laryngoscopy or bronchoscopy. An “Airway Huddle” should be done prior to starting induction to clarify the potential issues and agree on the type and sequence of airway options. 1. In addition to routine anesthesia equipment, anticipated difficult airway situations require laryngoscopes and air-

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way adjuncts to be ready on the surgical field, in close proximity to the surgeon, prior to the induction of anesthesia. This includes the immediate availability of a tracheostomy tray and cricothyrotomy/jet ventilation supplies. 2. Anesthesia airway adjuncts such as oral and nasal airways, laryngeal mask airways (LMAs), gum elastic bougie intubating stylets, and a videolaryngoscope should be immediately available. 3. All members of the surgical team should be aware of the anticipated difficult exposure along with the airway management plan and alternatives. 4. Everyone in the OR, including the attending surgeon and additional staff as indicated, must be attentive and available at the time of anesthesia induction to ensure the best outcome possible. 5. The patient is pre-oxygenated and anesthesia induction proceeds in a conservative manner, being sure to verify the ability to ventilate prior to administering a paralytic. 6. In an “unable to ventilate” situation, anesthesia may decide to administer a short acting paralytic and reattempt ventilation and/or direct laryngoscopy (see Sect. 10.5.4.2.3). Note: In an anticipated or known difficult airway, the provider with the most intubation experience should attempt direct laryngoscopy, regardless of title or role. Difficult airways are not appropriate for trainees, as the first attempt at a glottic view is often the best opportunity for successful intubation. Airway trauma and edema from inexperienced or multiple laryngoscopy attempts can significantly complicate the management of these patients.

Successful Ventilation; Successful Intubation If mask ventilation is successful, then a muscle relaxant is administered and direct laryngoscopy with standard intubation proceeds.

Successful Ventilation; Unable to Intubate If mask ventilation is successful, then a muscle relaxant is administered and direct laryngoscopy proceeds. If the larynx cannot be exposed through the oral route using direct laryngoscopy or videolaryngoscopy, then alternate methods of securing the airway must be employed. If the patient is able to be ventilated and maintains an acceptable SaO2, other techniques of securing the airway can be tried while general anesthesia is maintained. Advanced methods that may be tried by the laryngologist include:

K. J. Maresch et al.

Fig. 10.3  Intubation through an Ossoff-Pilling laryngoscope. A 5.0 or smaller ETT should be used

1. An Ossoff-Pilling (OP) laryngoscope (Teleflex, Morrisville, NC) (a) The OP laryngoscope is extremely valuable in patients with difficult, rigid, transoral airway exposure. (b) The OP laryngoscope is passed perorally and advanced to the level of the supraglottis. (c) A 5.0 MLT is placed directly through the laryngoscope. The balloon is inflated, position confirmed, and ventilation established until the patient is stabilized. (d) The laryngoscope can then be removed over the ETT with this approach (Figs. 10.3, 10.4, 10.5, 10.6, and 10.7). • The plastic connector is removed from the proximal end of the ETT. • The proximal ETT is grasped with a large laryngeal cup forceps. • The ETT is held stationary to prevent extubation while the OP laryngoscope is backed out of the oral cavity. • When the ETT can be visualized intraorally, it is secured by an assistant while the cup forceps are released and the OP laryngoscope is pulled back until the entire ETT and trailing cuff inflation tubing are passed through the lumen of the OP laryngoscope. 2. A Sliding Jackson (SJ) laryngoscope (Teleflex, Morrisville, NC) Note: Substantial experience with intubation in difficult laryngeal exposure patients is required before attempting this technique. This is not a preferred method of securing the airway and should only be used when all other options have failed.

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Fig. 10.4  Removal of the connector from the ETT to facilitate passage of the ETT through the laryngoscope

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Fig. 10.5  Laryngeal cup forceps are used to grasp the ETT

Fig. 10.6  As the laryngoscope is removed, the intraoral portion of the ETT is manually secured by an assistant

Fig. 10.7  The cup forceps are released as the entire laryngoscope is removed





(a) In select patients, when viewing the glottis with an OP laryngoscope is impossible, an SJ laryngoscope can be used for oral intubation. (b) Although an SJ laryngoscope does not provide superior visualization of the glottis in difficult patients with an anterior larynx for surgical procedures, it can be used as an intubating laryngoscope and then replaced with a more appropriate operative scope. (c) An SJ laryngoscope is used to displace the base of the tongue upward and provide a pathway for ETT placement. (d) A nonstyleted ETT is inserted through the laryngoscope and is guided through the scope and through the glottis.

(e) If the ETT can still not be advanced through the glottis, then a gum elastic bougie or cook catheter can be passed through the scope in an attempt to locate the glottis and advance the pliable stylet into the larynx. Then, an ETT can be passed over the bougie and into the trachea.

Unable to Ventilate If the patient cannot be mask ventilated, then the options are as follows (Fig. 10.8): 1. Insert an oral or nasal airway or both and reattempt ventilation. 2. Insert a laryngeal mask airway (LMA) or another supraglottic device and reattempt ventilation.

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Fig. 10.8  The ASA Difficult Airway Algorithm. (Reprinted with permission of Wolters Kluwer from Apfelbaum JL, Hagberg CA, Caplan RA, Blitt CD, Connis RT, Nickinovich DG, et al. Practice guidelines for

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management of the difficult airway: an updated report by the American Society of Anesthesiologists Task Force on Management of the Difficult Airway. Anesthesiology. 2013;118(2):251–70)

10  Anesthesia and Airway Management for Laryngeal Surgery: Surgeon’s Perspective

3. Abort the induction by administering no further medications, and allow the patient to breathe spontaneously and awaken. Proceed with alternate plans such as awake fiberoptic intubation or awake tracheostomy. 4. Consider administering a rapid and short-acting paralytic and reattempting ventilation or proceed to direct laryngoscopy. 5. Attempt direct laryngoscopy with a anesthesia laryngoscope (i.e., MAC, Miller, or Phillips blade) to assess the glottic view and potential for immediate intubation or 6. Attempt videolaryngoscopy for immediate intubation or 7. Attempt direct laryngoscopy with surgical laryngoscopes to assess the glottic view and potential for immediate intubation. Note: The ability to proceed with steps 5–7 will depend on maintenance of oxygen saturation during attempted laryngoscopies. If the patient critically desaturates, then proceed to an emergency invasive or surgical airway (see the section “Unable to Ventilate; Unable to Intubate”). Unable to Ventilate; Unable to Intubate If the above measures are unsuccessful and the patient critically desaturates, then proceed to an emergency invasive or surgical airway as per the American Society of Anesthesliogists (ASA) difficult airway algorithm (www. anesthesiology.org) 1. Needle cricothyrotomy with jet ventilation 2. An emergency cricothyrotomy catheter Bloomington, IN) 3. Tracheostomy

(Cook,

10.5.4.3 Subglottic or Tracheal Stenosis Securing an airway with subglottic or tracheal stenosis presents a unique challenge. 1. Ideally, the airway is not instrumented by the anesthesia team in the standard manner, as endotracheal intubation may result in traumatic injury to the subglottic mucosa. This could precipitate an emergency in a marginal but otherwise stable airway. 2. In this setting, the surgeon performs the initial direct laryngoscopy and then decides whether to proceed with a standard ETT, use jet ventilation, or awaken the patient for an elective tracheostomy before continuing with the planned procedure. 3. Due to the higher likelihood of conversion to an awake tracheostomy, the preoperative consent process should include this possibility. The use of local anesthesia at the tracheostomy site with minimal to no sedation should be discussed, including the possibility of intraoperative recall.

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Non-urgent Subglottic or Tracheal Stenosis 1. Preinduction preparation (a) The OR table is turned prior to induction, with the patient’s head directed toward the surgeon. This eliminates the problem of repositioning the bed with an unsecured and unproven airway. (b) All laryngoscopes, rigid bronchoscope, and instruments necessary for the planned airway management and alternatives must be ready and in close proximity to the surgeon. (c) The scrub technician or assistant must be attentive and ready to assist. (d) If jet ventilation is a possibility, then a handheld or automatic HFJV should be prepared and be in close proximity to the field for immediate use. If the jet is used, then the anesthesia team will need a non-­inhalational means of maintaining general anesthesia such as a propofol infusion, also prepared and ready to infuse. (e) Optimal positioning for laryngoscopy is verified (see Sect. 10.5.3). 2. Induction of anesthesia (a) Anesthesia induction in patients with subglottic stenosis with an unsecured airway must be carried out in an especially conservative manner. (b) Patients are maximally pre-oxygenated with 100% FiO2 prior to administration of induction agents and verification of the ability to mask ventilate. 3. Initial laryngoscopy and ventilation (a) When the patient is at an appropriate anesthetic depth, laryngoscopy is initiated, with placement of the scope tip just proximal to the stenotic region. (b) If necessary, jet ventilation is employed through the laryngoscope or with a ventilating tube such as the Hunsaker tube (see Chapter 11—“Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective”, Fig. 11.7). (c) If oxygenation cannot be maintained with jet ventilation alone, or if CO2 retention is excessive, then a small-diameter ETT can be intermittently inserted through the laryngoscope. This allows standard ventilation between working periods with apnea or HFJV as tolerated. 4. Emergence and extubation After treatment of the stenotic region, a decision is made regarding airway management for emergence from anesthesia. Although patient safety is of primary importance, reintubation with an ETT is preferably avoided due to the risk of unnecessary mucosal trauma or reactive airway edema in the subglottis. Options include: (a) Mask ventilation of an uninstrumented airway • Avoids trauma to the surgical site. • Requires dedication of one anesthesia provider to maintain mask seal and ventilate.

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(b) Insertion of an LMA • As an LMA is a supraglottic device, it does not traumatize the surgical site. • Allows mechanical or one-handed ventilation for the anesthesia provider. • Usually a mutually agreeable option for both the surgeon and anesthesiologist. (c) An ETT of appropriate diameter considering the posttreatment diameter of the stenotic area Urgent or Emergent Subglottic or Tracheal Stenosis The surgical approach to the treatment of urgent or emergent subglottic stenosis should be individualized to each patient. 1. An awake tracheostomy is the safest and the most conservative option, especially in a patient with a difficult surgical airway due to coexisting anatomic conditions. 2. If expert anesthesia and intensive care monitoring are available, then endoscopic treatments are generally preferable and a tracheostomy can be avoided. 3. The location and nature of the stenosis are critical in determining the method of securing and maintaining the airway during surgical treatment. (a) With severe subglottic stenosis confined to the infraglottis or cricoid, jet ventilation without endotracheal intubation can be used. Tracheostomy under local anesthesia is also a reasonable choice. (b) Subglottic or cervical tracheal narrowing due to cartilaginous collapse cannot always be anticipated preoperatively. Once recognized, an airway should be obtained by performing an awake tracheostomy under local anesthesia. An alternate method, if general anesthesia has been induced, is to secure the airway with a rigid bronchoscope. If ventilation is adequate, then proceed with a tracheostomy. • The tracheotomy entry point should be through the collapsed segment (Fig. 10.9). • This step minimizes the length of the trachea that must be excised when a tracheal or cricotracheal resection is performed at a later date.

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10.6.2 High-Frequency Jet Ventilation 1. Jet ventilation is a modality using higher-than-normal respiratory rates with extremely low tidal volumes (see Chapter 11—“Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective”, Sect. 11.3.4.2). 2. The advantages in airway surgery include an unobstructed surgical field and the ability to adequately ventilate through stenotic areas without an ETT or a tracheostomy. 3. Jet ventilation can be used through a laryngoscope with a ventilating channel or a specially designed small diameter airway catheter such as the Hunsaker tube. 4. Jet ventilation can be performed from a subglottic or supraglottic position (see Chapter 11—“Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective”, Sect. 11.3.4.2). (a) Supraglottic advantages • A clear surgical field with no ETT • Decreased risk of barotrauma because of more reliable egress above the stenotic area or lesion (b) Supraglottic disadvantages • Interference with precise surgical movements due to passive movement of the vocal folds with ventilatory air movement • Desiccation of tissues

10.6 Options for Intraoperative Ventilation 10.6.1 Endotracheal Tube with Traditional Ventilation 1. Traditional ventilation can be used with an ETT or a ventilating bronchoscope, with an ETT being the safer and preferred method of securing the airway. 2. A 5.0 or 5.5 microlaryngeal tube (MLT) is preferred.

Fig. 10.9  Illustration of an ideal tracheostomy entry point for cartilaginous collapse of the airway (indicated by arrow A). The length of the tracheal resection is reduced (segment A), compared with the amount requiring resection (segment B1) if the tracheostomy was placed more distally (arrow B)

10  Anesthesia and Airway Management for Laryngeal Surgery: Surgeon’s Perspective





• Possibility of repeated interruption or misdirection of airflow through the stenotic lesion. Jet flow occurs in a straight line, so it may be obstructed by surgical instruments or inadvertent movement of the jet venturi conduit, which requires the surgeon to repeatedly interrupt the procedure to reestablish a direct pattern of air movement through the narrowed airway. (c) Subglottic advantages • The jet conduit is below the level of the lesion, so ventilation is more reliable. • Less disruptive to surgery because the flow is less likely to be interrupted or misdirected. • Less vocal fold movement as compared to the supraglottic technique. (d) Subglottic disadvantages • Increased risk of air trapping below the level of the lesion. • Increased risk of barotrauma if egress is obstructed. • Small area of the airway is obstructed by the jet ventilation tube.

10.6.3 Intermittent Apnea In patients who are unsuited for or do not tolerate jet ventilation (i.e., morbid obesity, poor lung compliance), intermittent apnea may be an option. 1. This is especially useful in brief procedures that do not merit the risks of jet ventilation or in procedures below the level of a preexisting tracheostomy. 2. The apneic technique involves the repeated removal and reinsertion of an oral or stomal ETT.  Standard hand or mechanical ventilation is used between apneic intervals to reoxygenate with 100% FiO2. 3. The operating time between intubations will vary depending on how long an acceptable SaO2 can be maintained. 4. High flow nasal oxygen (THRIVE) can be used to supplement the airway in these situations.

10.6.4 Difficult-to-Ventilate Patients In certain cases, when an uninstrumented surgical field would be ideal, patients with significant comorbidities may poorly tolerate jet ventilation or intermittent apnea. 1. In these situations, it may be prudent to alter the originally planned surgical sequence to complete enough work to make space for the insertion of a small ETT, allowing the procedure to continue with standard mechanical ventilation. 2. For posterior glottic work, an ETT can be placed in the anterior glottis so that it rests on top of the laryngoscope.

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10.7 Surgical Fires and Risk Factors A surgical fire is defined as a fire that occurs on or in a patient during surgery and is estimated to occur 550–650 times annually in the United States. In otolaryngology, the most commonly reported surgical fires occur during endoscopic airway surgery and oropharyngeal procedures. The Joint Commission offers that virtually all surgical fires are preventable and that their impact can be lessened through an understanding of fire and how to fight it. The occurrence of a surgical fire requires three components: an oxidizer, an ignition source, and a fuel (fire triangle). A high-risk procedure is one in which an ignition source can come in proximity to an oxidizer-enriched atmosphere, thereby increasing the risk of fire (Fig. 10.10). 1. Oxidizer (a) An oxidizer-enriched atmosphere includes any oxygen level greater than room air and/or the addition of nitrous oxide in any amount, both of which increase the likelihood and intensity of combustion. (b) An oxygen-enriched environment can exist with closed, semi-closed, and open breathing systems. (c) Increased risk can also be created locally when drape configuration and an open oxygen source promote trapping or pooling of oxygen. (d) Although room air contains enough oxygen to support combustion, oxygen-enriched environments greatly enhance the risk of ignition and combustion. (e) Oxygen-enriched atmospheres lower the temperature at which fuels ignite and cause fires to burn more intensely and spread more quickly. 2. Ignition sources (a) Electrocautery (b) Laser • Surgical lasers are cited to be the second most frequent ignition source in OR fires. • Some have advocated for the use of instruments without a reflective surface during laser surgery to minimize the risk of laser energy being reflected to the surrounding locations. How there is little evidence to support the value of these instrument coatings. (c) Drills and burrs (d) Fiberoptic light cables 3. Fuel (a) Equipment • Gauze, pledgets, and sponges • Polyvinyl chloride (PVC) ETTs and suction tubing • Drapes and towels • Nasal cannulas and oxygen masks (b) Patient-related items • Head or body hair • Gowns • Blankets

84 Fig. 10.10  The ASA Operating Room Fires Algorithm. (Reprinted with permission of Wolters Kluwer from Apfelbaum JL, Caplan RA, Barker SJ, Connis RT, Cowles C, Ehrenwerth J, et al. Practice advisory for the prevention and management of operating room fires: an updated report by the American Society of Anesthesiologists Task Force on Operating Room Fires. Anesthesiology. 2013;118:271–90)

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10  Anesthesia and Airway Management for Laryngeal Surgery: Surgeon’s Perspective

10.7.1 Airway Fires An airway fire is a specific type of surgical fire that occurs in a patient’s airway or the attached breathing circuit. Although rare, it is a feared complication in laryngoscopic surgery. High-risk procedures include any case involving activations of a laser or electrocautery unit in the airway, especially if a non-laser-safe ETT or other flammable material is in place.

10.7.2 Laser Fires A laser fire is a specific type of fire that is ignited from a laser pulse. Due to an increased risk of airway fires with laryngeal lasering in microlaryngoscopy procedures, particular attention must be paid to the assessment of fire risk and fire prevention measures in this setting.

10.7.3 Assessment of Fire Risks Fire risk mitigation and prevention include predetermining whether a high-risk situation will exist (Fig. 10.10). With an experienced surgical and anesthesia team, this assessment will become routine and algorithmic. Points to consider include: • Does the planned procedure include use of electrocautery, laser, or a similar ignition source? • Will an oxygen-enriched environment exist? • Will the oxygen-enriched environment involve an open, closed, or semi-closed oxygen delivery device? • Which fuels will be available at the laser, cautery, or fire risk site?

10.7.4 Principles of Fire Prevention The following principles should be observed: 1. Minimize or avoid an oxidizer-enriched environment near the surgical site. (a) FiO2 should be kept as low as the patient will tolerate. • Decreasing the FiO2 can be guided by patient SaO2. (b) Use of nitrous oxide should be avoided. (c) Closed systems are preferable in situations where the patient is unable to be weaned to a safe FiO2. • Even with closed systems, recognition of a breach in the ETT cuff may not be instantaneous, so FiO2 must be decreased in the event of continued laser firing while cuff breach is recognized. (d) The surgeon must be aware of FiO2 and the current oxygen delivery method.



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(e) One should be wary of any unrecognized open oxygen sources such as an unconnected breathing circuit or a flow meter delivering extra oxygen to the room. For example, cases with intermittent reintubation could result in an open breathing circuit delivering a high flow of oxygen to the room during apneic or HFJV laser periods. This creates an unrecognized oxygen-enriched environment. During laser use, oxygen to flow meters or breathing adjuncts should be occluded or turned off when not connected to the patient. 2. Safely manage ignition sources (a) Place the electrosurgical device safely in its holster between uses. (b) Place the laser in standby mode when not in use. (c) Allow the laser to be activated only by the person using it. (d) Limit the laser operator to one pedal to avoid inadvertent laser firing. 3. Safely manage fuels (a) ETTs • Laser-resistant ETTs are used when lasering in or near the airway. • An ETT must be resistant to the specific laser in use based on the manufacturer’s recommendations. • A cuffed ETT is preferred over an uncuffed one. • Ideally, laser-resistant ETT has a double cuff. –– If the proximal cuff is violated, then the distal cuff provides continued isolation of airway gases and oxygen from the ignition source. –– If the proximal cuff is violated, then the ETT should be replaced with a new laser-resistant ETT with both cuffs intact. • An ETT cuff is filled with saline. • NSS is tinted with a colored dye such as methylene blue or fluorescenin to act as a visual marker for cuff puncture. (b) Prep solutions • Allow sufficient drying time for prep solutions, especially prior to draping. • Avoid pooling or spills. (c) Drapes • Arrange drapes to minimize oxygen buildup underneath. (d) Sponges, pledgets, etc. • Any material in or near the area being lasered should be moistened (this should include the string portion of a cottonoid). • Moistened materials should be periodically evaluated to assess the need for remoistening. 4. OR team members (a) Every team member is important in the event of a fire.

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3. O—One pedal (a) Verify that only one pedal is available to the laser operator. 4. P—Patient protection (a) Areas in close proximity to the laser are covered in wet towels or gauze. (b) Patient eye protection is facilitated with laser goggles, wet-soaked towels, or as per hospital policy or laser manufacturer recommendations. (c) Saline-soaked cottonoid/gauze is placed in the subglottis to protect the ETT cuff if there is an ETT. 5. S—Staff protection (a) All staff have laser-appropriate eyewear. (b) Display “Laser in Use” signs on all doors of entry. Fig. 10.11  Microlaryngoscopy laser safety measures, including a bulb syringe filled with saline within reach of the surgeon, a closed O2 delivery system, one pedal, patient protection with saline-soaked towels, and staff protections





(b) Every team member must be familiar with appropriate fire response, especially if they are not frequently involved in cases with the potential for airway fires. (c) Every team member should take immediate action in case of a fire without waiting for direction from others.

10.7.5 Safety Measures Safety checks should be completed in any case with a surgical or airway fire risk. In microlaryngoscopy cases, special attention is given to laser airway fire prevention (Fig. 10.11). Having a standard checklist that is used consistently and methodically on every fire risk case is the most sensible way to mitigate this risk. An example of a laser safety checklist that covers the relevant points is the pneumonic “SOOPS”: 1. S—Saline (a) A basin or bulb syringe of saline should be available on the surgical field. (b) Owing to the risk of airway fires (i.e., microlaryngoscopy with laser), an saline-filled bulb syringe should be within the reach of the surgeon to allow immediate action when a fire is recognized. 2. O—Oxygen level (a) Assess the current FiO2 levels and the possibility of lowering it to below 30% or to room air. (b) Assess the current oxygen delivery method. • Open (jet ventilation, face mask, nasal cannula) • Closed (ETT with cuff, LMA) • Semi-closed (ETT without cuff)

10.7.6 Special Situations 10.7.6.1 Sedation Cases Sedation cases require the same principles of laser safety as do general anesthesia cases. 1. Oxidizers should be minimized by eliminating or decreasing oxygen delivery near the surgical site. (a) Drape configuration must not allow pooling or trapping of oxygen in pockets. If drapes are required, then they should be flat against their underlying surface. (b) If patients are receiving intermittent oxygen, care must be taken to ensure that the oxygen delivery device is completely turned off or removed from the field so that an unrecognized oxygen-rich environment does not occur. For example, removing a face mask delivering oxygen at 10 L/min and laying it on the patient’s lap does not remove the oxidizer. It must be completely turned off and removed from the field for maximum safety. 2. Ignition sources must be safely stored or in a standby mode when not in use. 3. Fuels must be isolated with saline-soaked towels. 4. Special attention must be given to patient-related fuel sources such as hair and gown. Although it may be unpleasant to isolate these fuel sources in an awake or lightly sedated patient, priority must be given to fire safety and attempts should made to create a safe environment. Placing a waterproof drape between the patient’s skin or gown and wet towels may be a more comfortable option. 5. Saline should be readily available on the field even with non-intubated patients, as this is the quickest and easiest way to respond to a fire. (a) If there is potential for an airway fire in a sedated patient, then the surgeon may request saline in a bulb syringe within reach.

10  Anesthesia and Airway Management for Laryngeal Surgery: Surgeon’s Perspective

(b) Likewise, if the fire potential is drapes or external matter, requesting the saline in a basin or bowl may be a better choice. 6. Patients must also wear laser-approved eye protection.

10.7.6.2 Jet Ventilation with an Open Airway Jet ventilation poses a dilemma in terms of fire risk. If the jet stream is delivered through a laryngoscope, then there is technically no flammable foreign matter (fuel)  in the airway to catch fire. Unfortunately, there have been reports of airway fires in or near uninstrumented airways, with increased oxygen concentration believed to be a factor. One notable publication involved a surgeon’s glove being hit by an errant laser strike and the burning vapors being entrained into the patient’s airway and causing an oxygenenriched mixture to ignite the patient’s mustache and cause facial burns under the wet draping. The authors cited the high concentration of oxygen in the airway as a contributor to the incident. They later attempted to ignite the same surgical gloves with the same laser setting in room air but were not successful. Important considerations in laser use during jet ventilation include: 1. Many of the subglottic catheters currently available are laser-resistant but can degrade, puncture, deform, or fracture if their tolerance is exceeded. 2. Even when flammable materials are not in the path of the laser, charred tissue and laser plume can ignite in an oxygen-­enriched environment. 3. The lowest tolerated FiO2 should be used even in the uninstrumented airway. 4. All laser and fire safety principles should be followed, even in the uninstrumented airway.

10.7.6.3 Preexisting Tracheostomy Patients with a preexisting tracheostomy must have their stomal tube exchanged with a laser-safe ETT. Colored dye saline-filled ETT cuffs, decreased oxygen delivery, and all other standard fire prevention steps must be applied.

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10.7.7 Surgical Fire Management Management of an airway fire includes: 1. Recognize early signs of fire. (a) Flame or flash (b) Unusual sounds (c) Unusual odors (d) Smoke (e) Heat (f) Discoloration of the breathing circuit 2. Halt the procedure. 3. Immediately and loudly announce “fire” to all in room. 4. Stop the flow of all airway gases by disconnecting the breathing circuit or the delivery device. Remove ETT. Removing the ETT prior to stopping the flow of oxygen and other gases can result in a torch-like situation with flames continuing to flare from the distal end of the ETT. This endangers not only the surgeon holding the burning ETT but also the patient and others by increasing the risk of fire spreading to other objects. It is critical to disconnect the flow of gases prior to removing a burning ETT. 5. Remove sponges or other burning or flammable materials from the airway. 6. Pour saline in the airway or on the fire area. 7. Reestablish ventilation with a mask, avoiding supplemental oxygen or nitrous oxide. (a) If there are burning or smoldering fragments in the airway, then supplemental oxygen can support and worsen continued burning. (b) Mask ventilate with room air until confirmation that the fire is extinguished and no burning fragments remain in the airway. 8. Assess the airway for the remaining ETT fragments, assess the injury, and remove residual debris. (a) Consider bronchoscopy, preferably rigid. 9. Reintubate and continue ventilatory support. 10. Plan for ongoing care.

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Key Points • Lack of preoperative planning between the surgical and anesthesia teams can turn an otherwise simple microlaryngoscopy case into a chaotic, life-threatening airway crisis. All members of the OR team should be aware of potential difficult airway situations and be included in alternative and emergency airway plans. A preoperative “huddle” is a great tool to enhance patient safety. • A physical assessment of each patient’s airway in the preoperative area to identify predictors of difficult laryngoscopy or intubation is a vital step. Identifying a potentially challenging laryngoscopy will allow for the preparation and availability of additional equipment to aid in a difficult laryngeal exposure. • Any patient who is not deemed suitable by the anesthesia team for standard intubation with direct laryngoscopy is a red flag for surgical laryngoscopy. A team discussion of the airway assessment and reasons for alternate intubation plans are warranted. • Generally, lesions in the anterior two-thirds of the vocal folds can be adequately exposed and treated with a microlaryngeal ETT in place. Lesions on the posterior third of the larynx, vocal process, posterior commissure, or arytenoid regions may require jet ventilation or intermittent apnea. • In some patients, despite the likelihood of poor intubating conditions, the surgeon may choose to assess laryngeal exposure under general anesthesia with direct laryngoscopy or bronchoscopy. • An Ossoff-Pilling laryngoscope or an anterior commissure laryngoscope is an anterior scope that allows exposure of the glottis in 99% of surgical patients. It is extremely valuable in patients with difficult, rigid, transoral airway exposure. A Sliding Jackson laryngoscope can also be used as an intubating laryngoscope for placement of an ETT. • If a patient cannot be mask ventilated after induction of anesthesia, then options include oral airway, nasal airways, supraglottic devices such as laryngeal mask airway, allowing the patient to awaken, or attempting direct laryngoscopy for immediate intubation. If both ventilation and intubation are unsuccessful and the patient critically desaturates, then proceed to an emergency invasive or surgical airway. • With subglottic or tracheal stenosis, the airway should not be instrumented in the standard manner by the anesthesia

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team because of the potential for injury to the subglottic mucosa. This could precipitate an emergency in a marginal but otherwise stable airway. • In cases in which an uninstrumented surgical field would be ideal, patients with significant comorbidities may poorly tolerate jet ventilation or intermittent apnea. In these situations, it may be prudent to alter the original planned surgical sequence to complete enough work to make space for the insertion of a small ETT, allowing the procedure to continue with standard mechanical ventilation. • Virtually all surgical fires are preventable, and their impact can be lessened through an understanding of fire and how to fight it. Minimizing oxidizers, safely managing ignition sources, and limiting fuels are critical.

Bibliography AORN. Recommended practices for laser safety in perioperative practice settings. In: Perioperative standards and recommended practices for inpatient and ambulatory settings. Denver: AORN Publications; 2014. p. 125–40. Apfelbaum JL, Caplan RA, Barker SJ, Connis RT, Cowles C, Ehrenwerth J, et al. Practice advisory for the prevention and management of operating room fires: an updated report by the American Society of Anesthesiologists Task Force on Operating Room Fires. Anesthesiology. 2013a;118:271–90. Apfelbaum JL, Hagberg CA, Caplan RA, Blitt CD, Connis RT, Nickinovich DG, et  al. Practice guidelines for management of the difficult airway: an updated report by the American Society of Anesthesiologists Task Force on Management of the Difficult Airway. Anesthesiology. 2013b;118(2):251–70. ECRI Institute. New clinical guide to surgical fire prevention. Patients can catch fire—here’s how to keep them safer. Health Devices. 2009;38(10):314–32. Hagberg K, editor. Benumof’s airway management: principles and practice. 2nd ed. Philadelphia: Mosby Elsevier; 2013. Mehta S, Bhanaker S, Posner K, Domino K.  Operating room fires: a closed claims analysis. Anesthesiology. 2013;118:1133–9. Roy S, Smith L.  Surgical fires in laser laryngeal surgery: are we safe enough? Otolaryngol Head Neck Surg. 2015;152(1): 67–72. Santos P, Ayuso A, Luis M, Martinez G, Sala X. Airway ignition during CO2 laser laryngeal surgery and high frequency jet ventilation. Eur J Anaesthesiol. 2000;17(3):204–7. Smith L, Roy S.  Operating room fires in otolaryngology: risk factors and prevention. Am J Otolaryngol. 2011;32(2): 109–14. Wegrzynowicz E, Jensen N, Pearson K, Wachtel R, Scamman F. Airway fire during jet ventilation for laser excision of vocal cord papillomata. Anesthesiology. 1992;76:468–9.

Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective

11

Karen J. Maresch, Clark A. Rosen, and George W. Pasvankas

Commentary by Luis Leopoldo Llamas, MD

11.1

Fundamental and Related Chapters

Please see Chapter 10—“Anesthesia and Airway Management for Laryngeal Surgery: Surgeon’s Perspective”, Chapter 14—“Perioperative Care for Phonomicrosurgery”, Chapter 15—“Management and Prevention of Complications Related to Phonomicrosurgery”, Chapter 16—“Principles of Laser Microlaryngoscopy”, Chapter 36—“Principles of Awake Laryngeal Procedures”, Chapter 37—“Per-oral Vocal Fold Augmentation”, Chapter 43—“Principles of Laryngeal Framework Surgery”, and Chapter 44—“Perioperative Care for Laryngeal Framework Surgery” for further information.

11.2

Introduction

Laryngeal surgery can present unique challenges for anesthesia providers. Laryngology patients are more likely to present with complex airways or space-occupying lesions that may Commentary by Luis Leopoldo Llamas, MD. Department of Anesthesiology and Pain Management, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA K. J. Maresch (*) Department of Anesthesiology, University of Pittsburgh Medical Center, Pittsburgh, PA, USA e-mail: [email protected] C. A. Rosen UCSF Voice & Swallowing Center, Department of Otolaryngology-Head & Neck Surgery, University of California, San Francisco, San Francisco, CA, USA G. W. Pasvankas Anesthesiology and Perioperative Care, UCSF Pain Management Center, University of California San Francisco, San Francisco, CA, USA e-mail: [email protected]

complicate ventilation and airway management. Even minor glottic trauma on initial anesthesia laryngoscopy and intubation may alter surgical options or lead to an inability to perform the planned procedure. The airway is shared with the laryngeal surgeons who may require alternate means of ventilation or periods of endotracheal tube (ETT) removal and apneic work time. This population is also at an increased risk for postoperative laryngospasm, respiratory distress, glottic edema, and vocal fold dysfunction after airway manipulation.

11.3

Microsuspension Laryngoscopy

11.3.1 Team Preparations Prior to meeting each patient, a thorough review of old records, including prior laryngology procedures and airway management should be carried out. Important information to note include: 1. Ease of mask ventilation, supraglottic airway placement, and/or glottic view and intubation in non-airway surgeries as well as laryngology procedures. 2. Method of initial airway management for prior laryngology procedures. 3. Intraoperative airway issues such as ease of surgeon’s laryngeal exposure, alternative ventilation techniques used, periods of ETT removal, and tolerance of apnea. 4. Postoperative events such as laryngospasm or respiratory distress. 5. Operative reports and office notes may offer insights into previous surgical events and plans for the current procedure, and may prove more detailed and informative than standard presurgical documentation.

© Springer Nature Switzerland AG 2024 C. A. Rosen, C. B. Simpson, Operative Techniques in Laryngology, https://doi.org/10.1007/978-3-031-34354-4_11

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90 Table 11.1  Anesthesia checklist for laryngeal surgery Anesthesia checklist 1. Microsuspension laryngoscopy General anesthesia (GA) Preoperative: • Steroids (10–20 mg dexamethasone IV) • Glycopyrrolate (0.2 mg IV) • Acetaminophen (1000 mg PO) • Peripheral nerve stimulation monitor (automated Electromyography based neuromuscular transmission (E-NMT)) • Depth of anesthesia monitor (e.g., SedLine or BIS) if TIVA planned Intraoperative: • Paralytic agent • PONV prophylaxis • Laryngeal application of topical lidocaine 2. Laryngeal framework surgery (thyroplasty/arytenoid adduction) Preoperative: • Airway topicalization (e.g., nebulized 4% lidocaine 2 mg/kg and/or 1% tetracaine 0.5 mg/kg) • Steroids (10–20 mg dexamethasone IV) • Glycopyrrolate (0.2 mg IV) • Anxiolysis/amnesia—midazolam • Antibiotics • Acetaminophen (1000 mg PO) Intraoperative: • Sedation/anxiolysis/analgesia—prn • Remifentanil • Dexmedetomidine (bolus and/or infusion) • Midazolam • Fentanyl 3. “Awake” laryngeal surgery (trans-oral vocal fold injection, laser, etc.) Preoperative: • Airway topicalization (e.g., nebulized 4% lidocaine 2 mg/kg) • Steroid (10 mg dexamethasone IV, prn) • Glycopyrrolate (0.2 mg IV) • Anxiolytic, prn • Steroids, prn Intraoperative: • Sedation/anxiolysis/analgesia—prn • Remifentanil • Dexmedetomidine (bolus and/or infusion) • Midazolam  – Fentanyl

The surgical and anesthesia teams take a few minutes prior to each case to discuss the planned procedure (airway huddle). See Table 11.1. 1. The surgical team provides information on the patient’s pathology, surgical procedure, and any anticipated special airway needs or concerns, along with any problems during prior surgeries. 2. The anesthesia team provides information from old anesthesia records such as difficulties in ventilation or laryngoscopy during airway or non-airway surgery, along with any concerning medical history.

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3. If significant airway lesions are present such as Reinke’s edema, abnormal glottic appearance, or subglottic or tracheal stenosis, then the surgeon reviews office laryngoscopy videos with the anesthesia team to provide an additional insight into potential airway challenges. 4. The operating room (OR) circulator and scrub technician are included in these discussions so that everyone is aware of the potential areas of concern during the case, needed equipment and support, and planned sequence of airway management and surgical therapy. 5. An airway management plan is developed and agreed upon. This should include primary and backup airway options as well as a clear delineation of roles.

Commentary Certainly laryngology and anesthesiology have overlapping areas of expertise. Knowing the level of training and experience of the surgeon is most important. Most fellowship-­ trained laryngologists have good working knowledge of anesthesia techniques for airway surgery. The goal of these procedures is for the patient to have a better voice or more patent airway. As mentioned in the previous chapter, close collaboration and open communication should exist in a collegial fashion to ensure a successful outcome. Specifically, for the anesthesiologist, we must always respect the fundamentals of our practice. A good preoperative evaluation and a thorough pre-anesthetic machine check should be performed prior to proceeding. First, always check your pipeline and backup oxygen supply. Ensure that you have a self-inflating resuscitation bag mask (ambu bag), an adult and pediatric bougie, quality suction, a 4.0 MLT endotracheal tube with a pediatric stylet, a plugged in glidescope, and a functioning jet ventilation setup available. Have a discussion about what type of airway needs to be established. Are we going to share the airway with jet ventilation? Do we need a small MLT endotracheal tube? Will the endotracheal tube need to be laser protected? Is the airway so altered that ENT needs to intubate the patient instead after induction? Are there any delicate masses on the glottis opening that need to be carefully negotiated on intubation and are at risk of being dislodged and advanced into the trachea? Do we need to perform an awake tracheostomy, or an awake fiberoptic intubation on a spontaneously breathing patient? Coordinate with the ENT service to make sure every tool and instrument is ready such as a tracheotomy tray, telescope, light source, laser, hot water, etc. prior to induction of anesthesia. Get good at managing difficult airways, but always be ready to recognize the moment when it is necessary to turn the airway over to ENT before things go poorly. Be willing to “check your ego” in these scenarios and be thankful that at least you are doing difficult airways with surgeons that are very experienced at performing tracheostomies.

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11.3.2 Preoperative Care Preoperative care for laryngeal surgery cases includes: 1. A thorough patient interview with special attention to previous anesthetic experiences and airway procedures as above. (a) In some cases, patients are especially anxious because of their glottic injuries or other trauma from previous surgeries or intubations. (b) Patients may be singers, teachers, or in other professions, which require heavy voice use, and may be specifically concerned about damage from endotracheal intubation. 2. A standard American Society of Anesthesiologists (ASA) preoperative airway evaluation is conducted on every patient to assess the likelihood of an adequate glottic view (see Chapter 10—“Anesthesia and Airway Management for Laryngeal Surgery: Surgeon’s Perspective” Sect. 10.4.2). (a) Special attention is paid to the quality of dentition, given that laryngoscopy for intubation and/or the surgical portion of laryngoscopy can put significant stress on the teeth and occasionally lead to dental injury. (b) Any tooth damage must be noted prior to extubation to prevent aspiration of a broken fragment. (c) Some patients who have had cervical spine surgery or head and neck radiation (among other medical or surgical comorbidities) may display limited neck extension or decreased tissue pliability. 3. Postoperative airway concerns and plans should also be discussed and agreed upon prior to the start of the procedure. (a) Patients who undergo glottic enlargement procedures may awaken with the sensation that they are not moving air because of the unfamiliar decreased work of breathing. (b) Likewise, patients receiving glottic injections may feel an increased work of breathing because of a smaller glottic opening. (c) This is often an issue only in the immediate post-­ extubation period and usually responds well to reassurance. (d) In rare cases, patients may need judicious sedation due to severe anxiety. (e) Discussing these possibilities prior to surgery may make postoperative reassurances more effective. 4. Prior to laryngoscopy procedures, patients should receive glycopyrrolate 0.2  mg Intravenous push (IVP), unless contraindicated. (a) The anti-sialagogue action decreases airway secretions, which can improve surgical view and working ability. (b) The onset of action is approximately 10–15 min and the duration of action is around 2 h, so glycopyrrolate should be administered to the preoperative area or as early as is reasonable based on comorbidities and monitoring needs after administration.

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(c) Relative contraindications to glycopyrrolate include glaucoma and obstructive uropathy. (d) Cardiovascular comorbidities need to be considered prior to administering glycopyrrolate to patients, particularly those with a history of tachyarrhythmias. The baseline heart rate should be evaluated as well as the ability to tolerate tachycardia. 5. Short-acting intravenous (IV) anxiolytics such as midazolam are administered to most patients prior to OR transport. (a) Caution is advised in elderly/cognitively impaired patients and in those with sleep apnea or concern for significant airway compromise in the setting of mild sedation. Commentary In contrast with the outline, I am less inclined to use glycopyrrolate prophylactically to prevent bradycardia since it may cause more tachycardia than I care for in patients with coexisting coronary artery disease. Also, glycopyrrolate may excessively dry out the mouth making intraoperative repositioning of the suspension laryngoscope difficult for the surgeons.

11.3.3 Intraoperative Care 11.3.3.1 Positioning 1. Patients are positioned supine on the OR table in a classic sniffing position, with the tragus of the ear in line with the sternal notch (see Chapter 10—“Anesthesia and Airway Management for Laryngeal Surgery: Surgeon’s Perspective” Sect. 10.5.3). (a) This allows optimal alignment of the oral, pharyngeal, and laryngeal axes (Fig. 11.1). (b) There are special ramping pillows such as the Troop Elevation Pillow (Mercury Medical, Clearwater, FL) available to obtain a sniffing position, but these pillows may be longer than a patient’s torso and create a situation in which the patient slowly slides away from the surgeon during the procedure (Fig. 11.2a). (c) In short-torso patients, the optimal position for direct laryngoscopy (neck flexion, head extension) can be achieved with blankets and a foam pillow (Fig. 11.2b).

11.3.3.2 Monitors 1. Standard anesthesia monitors are applied, including electrocardiogram (ECG), noninvasive blood pressure (NIBP), pulse oximeters, and skin temperature monitors.

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a

2. A depth of anesthesia monitor may also be helpful, especially in cases in which their may be a limited or interrupted delivery of inhalational anesthetics or when using a Total Intravenous Anesthesia (TIVA) approach (e.g., intermittent apnea, jet ventilation). 3. In jet ventilation cases without the ability to monitor endtidal carbon dioxide (EtCO2), a transcutaneous CO2 monitor (SenTec, Fenton, MO) can be used to assess the adequacy of ventilation (Fig. 11.8).s

b

11.3.3.3 Induction

c

Fig. 11.1 Alignment of the oral, pharyngeal, and laryngeal axes. (a) The head in neutral position. None of the three visual axes align. (b) Elevation of the head approximates the laryngeal and pharyngeal axes. (c) Extension at the atlanto-occipital joint brings the visual axis of the mouth into better alignment with those of the larynx and pharynx. (Used with permission from Stone DJ, Gal TJ: Airway management. In Miller RJ (Ed.):Anesthesia 5th ed. Philadelphia, Churchill Livingstone, 2000, p 1419)

a

1. Patients are pre-oxygenated to obtain an end-tidal oxygen level >90%, and general anesthesia is induced. 2. Adequate mask ventilation is verified before any muscle relaxant is administered, unless a rapid sequence induction without mask ventilation is indicated. The increased potential for airway compromise in this population needs to be considered when balancing the risks of mask ventilation with those of rapid sequence induction. 3. If procedure length is potentially extremely short, a shortacting muscle relaxant such as succinylcholine may be warranted for induction and initial laryngoscopy; otherwise, intermediate-duration muscle relaxants may be used (e.g., rocuronium, cisatracurium). 4. After the return of twitches on train-of-four (TOF) monitoring, intermediate-duration muscle relaxants can be titrated to a goal based on TOF. One twitch indicates that the patient is >95% paralyzed, whereas two twitches indicate >90% paralysis.

11.3.3.4 Intubation 1. Anesthesia providers generally have a preferred blade for direct laryngoscopy. In laryngology cases, however, preb

Fig. 11.2 Classic sniffing position with the tragus of the ear aligned to the sternal notch using (a) a Troop Elevation Pillow and (b) blankets and a foam donut

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existing glottic pathology should be considered during blade selection. (a) The Miller is a straight blade and is placed under the epiglottis and lifted upward, so it may disrupt delicate tissues or fragile lesions if it comes in contact with the supraglottis or glottis. It is more similar in shape and technique to those used by laryngeal ­surgeons, however, and may provide a better preview of the impending visualization for the surgical team. (b) The Macintosh (aka “Mac”) is a curved blade and is placed in the vallecula with its tip protected by soft tissues, so, ideally, it should never come in direct contact with laryngeal pathology. For this reason, it may be preferred for friable lesions such as Reinke’s edema, papilloma, carcinoma, or exophytic polyps. 2. The ETT should be gently inserted and under the best visualization possible, especially with the diagnoses noted above. (a) Any damage caused by a difficult or traumatic intubation could lead to worsening of a preexisting condition or cancellation of surgery. (b) Debate exists over the prudence of using a stylet in every ETT.  The risk of glottic injury from a stiffer ETT with a stylet must be weighed against the potential for an anterior or difficult-to-instrument glottis and the better directional control obtained with a stylet. 3. Video laryngoscopes (VLs) are an excellent airway adjunct for cases with anticipated difficult laryngeal exposure. (a) In laryngeal pathologies, VLs are best used by experienced providers with good eye/hand coordination. (b) Poor aim of an ETT, particularly if a rigid VL stylet is used, can result in palatal, pharyngeal, and glottic trauma. (c) Using a VL for training purposes in laryngology may not be prudent, and the above risks must be weighed against the benefits of a potentially easier view and the ability for others to visualize what the anesthesia provider is seeing. (d) If a VL or fiberoptic bronchoscopy is needed for initial intubation, then the laryngologist needs to consider the potential difficulties in obtaining a workable laryngeal view for the planned surgery. The patient may need to be consented for other surgical options or outcomes, and a workable glottic view should be confirmed prior to any extensive preparations. 4. Under direct visualization of the glottis, laryngotracheal anesthesia (LTA) with 4 ml of 4% lidocaine is topically sprayed immediately prior to ETT insertion.

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5. With the exception of laser cases, laryngology patients are generally intubated with a 4.5 or 5.0 microlaryngeal tube (MLT) (Medtronic, Minneapolis, MN). (a) This small-diameter tube has an extended length for adults and allows maximal working space for the surgeon (Fig. 11.3). (b) Adequate tidal volumes are generally achievable, sometimes requiring permissiveness in higher airway pressures due to the small-diameter tube. In some patients, such as those who are morbidly obese or prone to retaining CO2, there may be challenges with adequate ventilation and hypercapnia may develop. (c) On emergence, patient-generated tidal volumes with a small-diameter tube in place will be smaller than expected and patients may have to be prompted to take in a deep breath “like you’re sucking through a straw” in order to adequately assess effort. (d) Tidal volumes generally improve greatly after extubation as long as patient strength and effort are adequate. 6. For laser cases, an appropriate laser-safe ETT is used, with a size of 4.5 or 5.0 (Fig. 11.4). (a) All standard laser precautions are put into place immediately prior to laser use (see Chapter 10—“Anesthesia and Airway Management for Laryngeal Surgery: Surgeon’s Perspective” Sect. 10.7). (b) Methylene blue-tinted saline should be used to inflate the ETT cuff(s) to allow early recognition of an intraoperative cuff rupture (Fig. 11.4). (c) Laser-safe ETTs with two cuffs are preferable because rupture of the saline with the methylene blue-filled proximal cuff alerts the surgeon to the breach while the distal cuff remains inflated to prevent an oxygen-enriched laser field. (d) Recognition of a breach in the ETT cuff is not immediate, as the blue dye may take several seconds to leak into the surgeon’s microscopic view and the source of changes in tidal volume or ventilation may take several breaths to become apparent. This slight delay in recognition can allow multiple laser pulses to the surgical site prior to identification of the cuff breach. 7. After verification of proper ETT placement: (a) An index finger is used to sweep the ETT to the left base of the tongue level to allow insertion of the laryngoscope from the right. (b) The ETT is secured at the left corner of the mouth. (c) Patient head and neck position is changed during laryngoscopy and suspension, so proper ETT depth should be reassessed by the surgeon after final positioning. • An ETT cuff that is visible immediately below the vocal folds can be a target for instruments such as the microdebrider or laser, and may need to be advanced. • Likewise, if the ETT cuff is not visible, then it may be prudent to pull back until it is visualized, to avoid a mainstem intubation.

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Fig. 11.3  Standard 5.0 ETT above and 5.0 MLT below. The increased length and larger cuff diameter of the MLT should be noted

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(b) The decision to stop laryngoscopy until heart rate (HR) recovers and whether to administer a chronotropic agent, along with dosing, is patient-specific. (c) Bradycardia-associated changes in blood pressure (BP) and arterial oxygen saturation (SaO2), along with preexisting cardiac comorbidities will guide the aggressiveness of treatment. 4. Once the scope is positioned and suspended in place, most patients exhibit significantly decreased stimulation and usually require minimal doses of intraoperative opioids. (a) Large doses of opioids during this early period can lead to delayed emergence and longer postanesthesia care unit (PACU) stay, so short-acting cardiovascular medications may be an alternative to control BP and/ or HR in an adequately anesthetized patient. (b) IV acetaminophen 15  mg/kg up to 1000  mg and/or ketorolac 15–30  mg IV are also administered for analgesia, if not contraindicated. Alternatively, administration of preoperative acetaminophen orally (PO) can be considered.

11.3.3.6 Muscle Relaxation Muscle relaxation is required for most laryngoscopy procedures, especially if the laryngoscope is rigidly suspended in a fixed position with a suspension system.

Fig. 11.4  Laser-safe ETTs (Tenax Laser Resistant Endotracheal Tube, Bryan Medical)

11.3.3.5 Surgical Laryngoscopy The most stimulating part of microlaryngoscopy cases is the initial surgical laryngoscopy and positioning. 1. If laryngeal exposure is easy, then this stimulation may be brief. 2. With a difficult exposure, there may be a significant amount of time with multiple attempts and laryngoscope changes before a workable view is obtained. 3. Bradycardia during laryngoscopy is less often seen in patients receiving glycopyrrolate 0.2  mg IV preoperatively due to its vagolytic activity. (a) If bradycardia does occur, then it can be treated with additional glycopyrrolate 0.2  mg IV or atropine 0.5–1 mg IV.

1. A nonparalyzed patient is at risk for laryngeal laceration and trauma or a laryngeal fracture if they cough or move while in rigid suspension. 2. Sugammadex is an IV agent used to reverse profound neuromuscular blockade by selectively binding and inactivating rocuronium and vecuronium. (a) Since doses vary considerably based on the density of blockade and the time and dose of the paralytic agent, readers are referred to current prescribing information for sugammadex, with the trade name Bridion (Merck & Co., Whitehouse, NJ). (b) It is noteworthy that females of reproductive age using hormonal contraceptives may have decreased contraceptive effects after receiving sugammadex due to a decrease in free plasma concentration. These patients should be counseled to use an additional, nonhormonal method of contraception for 7 days following sugammadex administration.

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Commentary It helps to give reversal agent to improve breathing effort immediately postoperatively. Familiarize yourself with sugammadex as a reversal agent. In my experience, patients have markedly improved return of strength with sugammadex as the reversal agent. If the patient is to be extubated at the end of the procedure, a smooth or deep extubation is preferred. Sometimes that is not possible with patients that were difficult to ventilate or intubate. In these cases, a wide awake extubation is indicated. Remember that these patients undergo sustained suspension laryngoscopy. Therefore, these patients are at high risk of laryngospasm at the end of surgery. Be ready to break laryngospasm with a two handed jaw thrust and positive pressure mask ventilation. IV lidocaine bolus or intraoperative administration of 2 g of Magnesium Sulfate IV may help to prevent laryngospasm. Rarely, a small dose of succinylcholine or non-depolarizing muscle relaxant is needed to break severe laryngospasm. Make sure that the patient is awake, strong, and breathing comfortably at the end of the procedure. I like to place a racemic epinephrine nebulizer mask on the patient for transport to the PACU. A racemic epinephrine nebulizer mask has three benefits: it reduces airway edema by acting as a vasoconstrictor, it is a bronchodilator, and it delivers 10  l of oxygen per minute.

11.3.3.7 Postoperative Nausea and Vomiting (PONV) Prophylaxis Postoperative nausea and vomiting (PONV) prophylaxis is indicated for all laryngology patients. 1. Vomiting with resultant gastric acid on a newly disrupted laryngeal tissue can lead to poor healing and further tissue damage. 2. Heaving and vomiting after vocal fold injections can contribute to extrusion of the injectate and essentially negate the procedure. 3. Patients should be well-hydrated to replace fluid deficits. 4. Ondansetron 4  mg IV is routinely administered to all patients. 5. Measures may be taken to reduce gastric content acidity in patients with a history of PONV, such as Bicitra (sodium citrate) orally preoperatively and/or H2 blockers such as famotidine 20 mg IV intraoperatively. 6. Scopolamine 1.5-mg transdermal patch and/or aprepitant 40 mg PO can be added preoperatively for patients with a history of PONV. 7. Dexamethasone also plays an antiemetic role but is administered in higher doses of 10–20 mg IV to prevent airway edema.

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(a) Ideally, dexamethasone should be administered prior to the initiation of surgical laryngoscopy or any manipulation that may initiate edema or inflammation. (b) If administered in the awake patient, it should be given slowly and incrementally to avoid the possibility of perineal pain/pruritus.

11.3.3.8 Antibiotics Antibiotics are not routinely given for microsuspension laryngoscopy procedures unless indicated by the American Heart Association (AHA) guidelines.

11.3.4 Ventilation Options There are several options for intraoperative ventilation: 1. Conventional ventilation 2. Jet ventilation (hand or high frequency) 3. Intermittent apnea

11.3.4.1 Conventional Ventilation Most microsuspension laryngoscopies are managed with a standard 4.5 or 5.0 MLT or a laser-safe ETT and conventional ventilation. In cases in which an ETT will obscure the surgeon’s working view, high-frequency jet ventilation (HFJV) or an intermittent apneic technique can be used. 11.3.4.2 High-Frequency Jet Ventilation 1. High-frequency jet ventilation (HFJV) pairs higher-than-­ normal respiratory rates with extremely low tidal volumes (see Chapter 10—“Anesthesia and Airway Management for Laryngeal Surgery: Surgeon’s Perspective” Sect. 10.6.2). 2. It allows ventilation through a laryngoscope with a jet or suction channel (Fig. 11.5) or a specially designed small-­ diameter airway catheter such as the Hunsaker Mon-Jet tube (Medtronic, Minneapolis, MN) (Fig. 11.6). 3. Jet cannula delivery can be supraglottic or mid-tracheal. 4. This provides an unobstructed surgical field and is an effective method for ventilating patients with high-grade laryngeal stenosis or lesions. 5. HFJV can be delivered via a manually triggered handheld device or an automatic jet ventilator (Acutronic Monsoon III, Hirzel, Switzerland) (Fig. 11.7).

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Fig. 11.7  An Acutronic Monsoon III jet ventilator (Hirzel, Switzerland)

Fig. 11.5  Jet ventilation setup via surgical scope with suction channel (arrow indicates jet catheter)

a

b

Fig. 11.6  Jet ventilation setup using the Hunsaker Mon-Jet tube (Medtronic, Minneapolis, MN). (a) A Hunsaker tube with a stylet as packaged; (b) A Hunsaker tube attached to jet tubing

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Handheld Jet Ventilators Handheld jet ventilators are frequently used for extremely short procedures such as rigid bronchoscopy.



1. A handheld jet requires a high degree of attention from the anesthesia provider, making distractions or interruptions such as medication administration, equipment preparation, or charting challenging. 2. Jet pulse strength, duration, and frequency will vary with the comfort level of the jet operator and the duration of jet time, meaning that the longer one is activating the hand jet, the more likely the jetting hand will fatigue and weaken and jet pulses will be increasingly inconsistent. 3. A great disadvantage of the handheld jet is the lack of automatic alarms for progressively increasing or sustained positive end-expiratory pressure (PEEP) and risk of barotrauma.



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(c) This entrained air causes the FiO2 reaching the distal airways to likely be lower than the set value, although this is not measurable. (d) If necessary, then this drop in FiO2 can be offset by delivering supplemental oxygen in or near the oral opening, allowing entrainment of oxygen-enriched air. (e) Supplemental oxygen should not be used during laser or electrocautery due to the creation of an oxygen-­ enriched environment not only in the airway but also around the surgical field and surgeon, with a resultant increased risk of surgical fire if a flammable item is hit by the laser or electrocautery (see Chapter 10—“Anesthesia and Airway Management for Laryngeal Surgery: Surgeon’s Perspective” Sect. 10.7).

HFJV Delivery Automatic High-Frequency Jet Ventilation Automatic HFJV is more consistent, precise, and reliable than is manual jet ventilation (Fig.  11.7). Each HFJV provides manufacturer recommendations for initial settings and acceptable ranges. Adjustable settings include: 1. Driving pressure (DP) (a) DP is the pressure at which jet pulses are delivered. (b) It is initially adjusted to obtain visible chest excursion and may be manipulated to obtain better oxygenation or elimination of CO2. (c) A reasonable initial DP is 20–25 depending on patient size. (d) This may be increased quickly in large or obese patients requiring significantly higher pressures to elevate the chest wall. 2. Pulse delivery rate (R) (a) R is generally started at 100–120 pulses per minute. 3. Inspiratory time (IT) (a) IT can be compared to the I:E ratio in conventional ventilation, with only the inspiratory portion programmed. (b) An IT of 40% is equivalent to an I:E of 1:2.5. 4. FiO2 (a) FiO2 is initially set at 100% but may be decreased as tolerated. (b) Due to the open nature of HFJV in laryngology cases, room air is entrained with each jet pulse due to the Venturi effect.

1. The jet ventilates in a coaxial flow pattern, with active inflow moving in a straight line from the jet cannula into the airway, ideally aimed at the center of the airway. 2. Passive outflow or egress happens along the periphery of the airway. 3. Because of this flow pattern, the ventilating cannula must be centrally positioned. (a) If the jet stream is angled, then it will reflect off of the lateral airway tissue, vocal folds, or stenosis and not flow down the airway in a smooth, linear pattern. (b) Turbulent flow decreases effective ventilation and can be disruptive to the surgeon if it increases movement of the working area. (c) If jet delivery is performed using a laryngoscope, then great care should be taken to make sure that the jet is centered over the airway. This should be remembered when the laryngoscope is repositioned intraoperatively. 4. HFJV can be delivered through a ventilating cannula in a supraglottic or subglottic position attached to the laryngoscope or through a Hunsaker Mon-Jet tube (mid-trachea). (a) One advantage of the Hunsaker Mon-Jet tube is its distal basket, which is designed to center the jet cannula in the airway lumen, allowing central delivery of jet pulses and decreasing obstruction against the lateral wall or trauma to the tracheal mucosa.

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Supraglottic Jetting 1. Supraglottic jetting has the advantage of an uninstrumented surgical field and a decreased risk of barotrauma. 2. Disadvantages include: (a) Surgical instruments may intermittently obstruct inflow, especially with a narrow working space. (b) Ventilatory air movement may create vocal fold movement, which can interfere with precise surgical movements. (c) Air inflow across the glottis may result in tissue desiccation and cause vocal fold vibration. 3. Surgeons must remain vigilant so that loose items such as pledgets are not placed below the jet stream because they may be jetted into the distal airways.

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2. To prevent or minimize these complications, vigilance by both the surgeon and the anesthesia provider in monitoring and addressing HFJV alarms is critical. It is also prudent to have equipment for emergent chest decompression and subsequent chest tube insertion readily available during any HFJV case. CO2 Monitoring Although the Hunsaker Mon-Jet tube has a side port for CO2 sampling, displayed values have proven to be unpredictable and inaccurate. In our experience, this measurement does not correlate with arterial blood gas CO2 values or reliably follow CO2 trends. In lieu of inserting an arterial line to check partial pressure of carbon dioxide (PaCO2) values, a transcutaneous carbon dioxide (TcCO2) monitor (SenTec, Fenton, MO) (Fig.  11.8) may be used during jet cases.

Tracheal Jetting 1. Tracheal jetting is a more reliable means of inflow because the jet port is located below the level of the lesion. 2. Inflow is less likely to be misdirected, and there is less potential for movement of the surgical field. 3. The disadvantage is an increased risk of air trapping and barotrauma if egress is obstructed. 4. Some sources suggest that a tracheal location of the jet cannula may entrain less room air and deliver a more reliable FiO2, but converting to a tracheal jet position rarely improves oxygenation in patients with a poor SaO2 during supraglottic jetting. Humidification

1. This monitor is applied to the skin and correlates well with EtCO2 in most patients, especially if HR and SaO2 values as measured by the TcCO2 sensor correlate as well. 2. Accuracy in individual patients can be correlated with EtCO2 while mask ventilating, prior to laryngoscopy, or with intermittent insertions of an ETT, prior to apneic working periods.

11.3.4.3 Intermittent Apnea Those patients who do not tolerate HFJV (i.e., morbid obesity, decreased lung compliance, significant pulmonary disease with a ventilation/perfusion (V/Q) mismatch) or in cases in which jet pulsations create disruptive movement of the surgical field, intermittent apnea may be an option.

1. Humidification can be delivered through automatic HFJV. 2. Sterile water is delivered in a programmed concentration of 30–100% with each jet pulse. 3. The surgeon can assist in obtaining the best humidification setting for each patient by noting the dryness or hydration of the airway tissues. 4. Humidification can be increased or decreased based on visual observations and working conditions. Pause Pressure Alarm The Acutronic Monsoon III jet ventilator has a “pause pressure” alarm, which detects end-expiratory pressure from the jet delivery aperture. 1. This alarm detects increasing or sustained PEEP, indicating a risk for barotrauma, which may result in unilateral or bilateral pneumothoraces, pneumomediastinum, or emergent ventilatory compromise.

Fig. 11.8  A transcutaneous CO2 monitor (SenTec, Fenton, MO)

11  Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective

1. This involves the repeated removal and reinsertion of an ETT through the laryngoscope. 2. This technique is also used to complete work below the level of a tracheostomy stoma where the stomal tube obstructs visualization. 3. Patients are conventionally ventilated with 100% oxygen to an end-tidal oxygen >90%. 4. The ETT is then removed to allow surgical working time. 5. When the SaO2 decreases to a predetermined level, the ETT is reinserted and the patient is conventionally ventilated with 100% oxygen. 6. Surgical working intervals will vary depending on how long an acceptable SaO2 can be maintained while apneic. 7. In patients requiring recurrent procedures (i.e., papilloma), it is helpful to document tolerated apneic time and time to achieving full resaturation for future reference. 8. High flow of nasal oxygen may assist in apneic periods.

11.3.4.4 Surgical Plan Alteration Some patients do not tolerate HFJV, have rapid oxygen desaturation with apnea, require lengthy resaturation time between apneic working periods, or have comorbidities that make recurrent desaturations undesirable or contraindicated (e.g., severe pulmonary hypertension). In these cases, the original surgical plan or sequence may need to be altered or adjusted to allow early insertion of a small ETT. 1. Completing enough work to allow ETT placement and conventional ventilation will allow the remaining surgical procedure to proceed uninterrupted with stable oxygen delivery to the patient. 2. This may also be considered in patients who have significant CO2 retention and require recurrent interruption of surgery to conventionally ventilate them back to safe CO2 levels.

11.3.5 Emergence 1. At the completion of surgery, the surgeon should be encouraged to administer an additional 4% lidocaine LTA before the laryngoscope is removed. (a) To prevent toxicity in short or low-weight patients, the total amount of intratracheal and intravenous lidocaine administered must be considered. (b) Since this LTA is administered above the ETT with the cuff inflated, it may help anesthetize the glottis and decrease laryngospasm. (c) Care must be taken by the surgeon to avoid suctioning the airway and removing the laryngotracheal lidocaine after it has been administered.

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2. Prior to completely removing the laryngoscope, the surgeon passes an orogastric tube (OGT) under direct visualization. (a) This evacuates stomach contents and intragastric air, which may contribute to PONV or reflux onto laryngeal tissues. (b) It is preferable to pass the OGT with a laryngoscopic view of the esophageal inlet, as a blindly passed tube may traumatize laryngeal tissues. 3. A smooth emergence and extubation with minimal to no coughing or bucking is vital. (a) Coughing during emergence can increase glottic trauma and edema and extrude any injectate or disrupt the surgical site. (b) In cases in which the sole purpose of surgery is to augment the vocal folds with an injectate, a vigorous wake up with coughing, bucking, and gagging can entirely negate the procedure. (c) A gentle emergence should be the goal without vigorous suctioning or stimulation. (d) Unfortunately, a smooth extubation can be especially challenging in smokers and in other patients with hyperactive airways.

11.3.6 Post-extubation Concerns Collaboration between the surgeon and the anesthesia provider is essential in assessing and treating post-extubation issues, including the following: 1. Partial or complete laryngospasm 2. Glottic edema 3. Subjective dyspnea 4. Glottic or vocal fold dysfunction 5. Post-obstructive pulmonary edema

11.3.6.1 Laryngospasm 1. Just prior to removing the laryngoscope, an LTA is administered by the surgeon to decrease the likelihood of post-­ extubation laryngospasm. In some cases, partial or complete laryngospasm still occurs. 2. Patients can be completely awake and responsive while experiencing a partial laryngospasm, usually complaining of dyspnea with high pitched inspiratory stridor and much anxiety. (a) Lidocaine 40–50 mg IV will frequently resolve partial laryngospasm almost immediately. (b) Partial laryngospasm may also break if the patient is cooperative enough to sniff through the nose with a closed mouth. Slowly sniffing through the nose is theorized to create a reflex opening of the vocal folds.

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3. Complete laryngospasm is usually preceded or followed by a decreased level of consciousness with no sign from the patient that they are in distress. (a) If the SaO2 is maintained, then this is treated with positive airway pressure followed by lidocaine 40–50  mg IV while ventilation is supported as needed. (b) In refractory cases with desaturation, small doses of IV propofol or succinylcholine are administered, with airway support continuing until the patient regains consciousness and adequate respiratory effort.

11.3.6.2 Glottic Edema Glottic edema is a rare postoperative finding. In patients with stridor or dyspnea in PACU, a flexible laryngoscopy can be expediently performed by the surgeon to assess the airway. 11.3.6.3 Subjective Dyspnea After glottic manipulation, patients may experience subjective dyspnea despite the objective appearance of good air exchange. 1. An anatomic reason can be ruled out with a flexible laryngoscopy in the PACU. 2. Rarely will patients receiving LTAs at the completion of surgery have decreased laryngeal sensation of breathing and interpret this as dyspnea. 3. After glottic enlargement procedures, patients may awaken with the sensation of not moving air because of an unfamiliar decreased work of breathing. 4. Patients receiving glottic injections may feel an increased work of breathing because of a smaller glottic opening. 5. This is often an issue only in the immediate post-­extubation period and usually responds well to reassurance. 6. In rare cases, patients may need careful sedation for severe anxiety. 7. Discussing the possibility of changes in glottic sensation prior to surgery can make post-extubation reassurances more effective.

11.3.6.4 Glottic or Vocal Fold Dysfunction A rare but serious problem encountered in the immediate postoperative period is post-procedure vocal fold dysfunction (also referred to as “paradoxical vocal fold motion” or PVFM), especially in patients with preexisting bilateral vocal fold pathology.

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1. Surgical manipulation may result in altered function and the need for urgent reintubation and mechanical ventilation until this resolves. 2. A trial with noninvasive positive pressure ventilation such as CPAP or BiPAP may also be considered. 3. Having the patient breathe through a short 3–4-inch straw may redirect the constriction to the oral cavity, which often breaks the pattern.

11.3.6.5 Post-obstructive Pulmonary Edema 1. Post-obstructive or negative pressure pulmonary edema (POPE) is a form of noncardiogenic pulmonary edema resulting from the generation of highly negative intrathoracic pressures in an attempt to overcome airway obstruction. 2. Highly negative inspiratory intrathoracic pressures against an obstructed airway is theorized to be a factor. (a) Changes in pulmonary pressures draw fluid from the interstitial space into the alveoli. (b) When the airway obstruction is relieved, pulmonary edema remains. 3. This can occur in patients undergoing balloon dilation of the trachea. It is a result of inspiratory effort by an incompletely anesthetized patient against an occluded trachea. The surgeons must be vigilant to insure there is no chest rise during balloon dilation. 4. This can follow post-extubation laryngospasm or obstruction of an ETT by patient biting during emergence. POPE can also be seen after removal of an obstructing glottic or pharyngeal mass. 5. Interestingly, it is more commonly seen in young, healthy, and muscular patients who are capable of generating highly negative inspiratory efforts. 6. Unexpectedly low and persistently poor SaO2 or respiratory difficulties in PACU, especially in otherwise healthy patients, warrant suspicion for POPE. 7. Lung auscultation and a chest X-ray generally reveal rales and pulmonary infiltrates indicative of edema. 8. Quick recognition and intervention in laryngospasm or acute airway obstruction are the key to preventing POPE. 9. Treatment goals include treating hypoxia with supplemental oxygen and decreasing fluid volume in the lungs. 10. In refractory cases, noninvasive positive pressure ventilation, such as Continuous positive airway pressure (CPAP) or Bilevel positive airway pressure (BIPAP), or reintubation with positive pressure ventilation and PEEP may be necessary.

11  Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective

11.4 Abdominal Fat Harvest and Lipoinjection of the Vocal Folds Abdominal fat harvest with vocal fold lipoinjection (see Chapter 30—“Vocal Fold Augmentation: Phonomicrosurgery”) has unique postoperative concerns. 1. Fat is harvested from the abdomen and then prepared for injection into the vocal folds. 2. This special preparation includes bathing the fat in a large dose of regular insulin, rinsing with several liters of saline, and then injecting a variable quantity of the prepared fat into the vocal folds. 3. This insulin bath is postulated to improve lipocyte survival and the success of the injection. 4. The amount of insulin, saline, and fat harvested varies with each patient and surgeon’s protocol, so it is difficult to reliably estimate the amount of exogenous insulin in the injection. 5. This lipoinjection may mimic a subcutaneous (SQ) insulin injection and occasionally leads to persistent postoperative hypoglycemia. (a) This is especially apparent in patients with a delayed oral intake in the PACU. 6. Since it is not possible to predict who will become hypoglycemic, all lipoinjection patients are monitored for 4 h in the PACU with serial glucose measurements. 7. PO intake is encouraged as soon as possible, and additional IV dextrose boluses are administered as needed. 8. Baseline glucose is measured preoperatively, on arrival to the PACU, 1, 2, and 4 h post-arrival and additionally as needed in hypoglycemic patients. 9. It is important to inform the patient and family in advance of the 4-h postoperative monitoring period to establish reasonable expectations.

11.5 Laryngeal Framework Surgery: Medialization Laryngoplasty and Arytenoid Adduction 11.5.1 Monitored Anesthesia Care (MAC) 1. Patients must be calm and still during open neck surgery yet intermittently respond and cooperate to phonate on request. 2. Historically, these cases were often conducted like many other monitored anesthesia care (MAC) cases with agents such as midazolam, fentanyl, and/or a pro-

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pofol infusion. This often resulted in a well-sedated patient with frequent upper airway collapse and in a disoriented, temporarily uncooperative patient when sedation was discontinued for phonation. 3. Dexmedetomidine (Precedex) is highly effective in achieving the desired sedation level with minimal airway collapse and a still, cooperative patient. (a) Dexmedetomidine is a selective alpha-2 agonist with unique properties of sedation, anxiolysis, and analgesia with minimal respiratory depression. (b) It has a predictable distribution half-life of 6  min and an elimination half-life of 2 h. (c) It has sympatholytic and vagomimetic effects, which may result in hypotension and bradycardia, although rapid injection of the drug may cause transient hypertension through binding of the alpha-2 receptors on vascular smooth muscle. (d) The main disadvantages are its lack of amnestic effect (as compared to benzodiazepines) and its lessened analgesic effect/airway reflex suppression (as compared to opioids). Patients will appear comfortable and sedated yet have total awareness and recall of intraoperative events. (e) To aid in amnesia, analgesia, and airway reflex suppression, repeated small doses of benzodiazepines and/or opioids (such as midazolam and fentanyl) may be warranted throughout the case as a supplement, although the overall goals of cooperation and airway stability must be prioritized for the best surgical outcome. Remifentanil infusion can be used as an alternate or supplemental option. This can provide sedation as well as the beneficial analgesic and airway suppressive effects of opioids but with a rapid offset and infusion titratability not seen with IV bolus opioids such as fentanyl. 4. Laryngoplasty patients must be agreeable and prepared for intraoperative awareness of events. (a) Most patients agree to this type of anesthetic if they understand that visualizing vocal fold movement and hearing phonation during surgery achieves the best possible voice. (b) They must be reassured that an additional local anesthetic will be administered as needed at the surgical site and small doses of analgesia or anxiolytics as appropriate. (c) They will be able to talk and communicate with staff during the procedure to verbalize pain or other concerns.

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5. Preoperatively, laryngoplasty patients need: (a) Topical anesthesia of the airway to allow intraoperative flexible laryngoscopy down to the level of the glottis. • This also helps decrease discomfort with external laryngeal manipulation. • Nebulized local anesthetic dose is 4% lidocaine 2 mg/kg and 1% tetracaine 0.5 mg/kg delivered through a standard airway nebulizer. • Depending on the volume, this usually takes 10–20 min to administer. (b) Glycopyrrolate 0.2 mg IV to decrease airway secretions (see Sect. 11.3.2). (c) Antibiotics at the surgeon’s discretion and as per the AHA guidelines. 6. En route to the OR, small doses of midazolam and/or fentanyl may be administered to provide mild sedation, as phonation is not needed until later in the procedure. 7. Patients are positioned in a supine recliner position with the head of bed elevated, knees bent, and shoulders roll back to provide neck extension and exposure of the thyroid cartilage (Fig. 11.9). 8. In the OR, after patient positioning and application of standard monitors and oxygen, patients receive: (a) Dexmedetomidine bolus of 0.5–1  μg/kg administered over 10 min via an infusion pump as per manufacturer recommendations or initiation of infusion without bolus. (b) A local anesthetic injection to the incision site when the patient is comfortable and supplemented as needed throughout the procedure. (c) Fentanyl boluses carefully titrated for overall patient comfort, as they may remain in the same position for several hours.

Fig. 11.9  Patient positioning for medialization laryngoplasty

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(d) Midazolam boluses carefully titrated for mild sedation and possible amnesia. (e) Acetaminophen 15 mg/kg up to 1000 mg IV. (f) Dexamethasone 10–20 mg IV prior to incision to decrease edema from surgical airway manipulation. 9. If an arytenoid adduction is also planned, then the surgeon may perform a unilateral superior laryngeal nerve block on the side of the planned adduction. (a) This significantly decreases patient discomfort when the larynx is rotated to identify the muscular process of the arytenoid cartilage. (b) This block is easily performed at the time of local injection at the planned incision site. 10. To provide sedation for the remainder of the case, a dexmedetomidine infusion may be utilized. (a) The initial infusion rate is 0.2–0.7 μg/kg/h and can be titrated to obtain an optimal level of comfort and cooperation with careful boluses of anxiolytics or analgesics if needed. (b) If pain can be addressed by the surgeon with an additional local anesthetic, then this is the best option to limit sedation. 11. Because of the close proximity of the surgical site and electrocautery use to the uninstrumented airway, fire prevention measures must be employed for all patients (see Chapter 10—“Anesthesia and Airway Management for Laryngeal Surgery: Surgeon’s Perspective”) Sect. 10.7).

11.5.2 Sequential Anesthesia Technique Sequential anesthesia technique is general endotracheal anesthesia followed by sedation analgesia for arytenoid surgery associated with laryngeal framework surgery (see Chapter 47—“Arytenoid Adduction” and Chapter 48—“Adduction Arytenopexy”). Recently, an alternative to MAC for laryngeal framework surgery has been advocated using a sequential anesthesia approach (Rosero et al., 2016). This technique involves starting the surgery under general anesthesia with an ETT followed by the surgeon performing all the aspects of the arytenoid surgery other than the final assessment of vocal fold positioning. This final portion is performed under MAC, which requires the anesthesia team to coordinate with the surgeon to transition from general anesthesia (GA) to MAC at the proper time to allow voice and vocal fold position assessment by the surgeon under MAC.

11  Anesthesia and Airway Management for Laryngeal Surgery: Anesthesia’s Perspective

11.6 “Awake” Laryngeal Surgery Involving Sedation Awake airway procedures such as vocal fold injections or laryngeal laser treatment may not be successful with only topical anesthesia in patients with a strong cough or gag or high levels of anxiety. Historically, these patients were offered a microsuspension laryngoscopy with general endotracheal anesthesia as their only choice. Topical airway anesthesia with mild sedation has increasingly proven to be a viable option for these cases. 1. Patients of advanced age, with significant comorbidities, or abnormal baseline vital signs (i.e., hypertension) may also benefit from monitoring and mild sedation during their “awake” procedures. 2. Preoperative care includes: (a) Standard preoperative preparation, including the nil per os (NPO) guidelines. (b) Consent and clearance for sedation as well as general anesthesia, allowing immediate conversion to MSL if the “awake” procedure is not successful. Being able to proceed immediately to General endotracheal anesthesia (GETA) and microsuspension laryngoscopy (MSL) prevents the patient from needing to return on a different day. (c) Patient counseling that this will be a conscious procedure with likely recollection of intraoperative events. Vital sign monitoring and mild sedation will be provided, but patients will remain conscious and will be aware to allow cooperation with the surgeon. (d) Airway topicalization with 4% lidocaine 2  mg/kg delivered via a standard airway nebulizer 10–15 min prior to OR transport. (e) Anti-sialagogues as needed (prn). (f) Antiemetics, prn. (g) No antibiotics. (h) No steroids unless requested by the surgeon.

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3. Patients are positioned on the OR table or on a narrow transport cart that allows the easiest access to the patient. Intraoperative care includes: (a) Head of bed elevated to 90° with a foam pillow placed behind the head to provide support and stability. Arms resting in a comfortable position (seated upright position). (b) Standard monitors, including ECG, NIBP, and SaO2. (c) Supplemental oxygen can be used when appropriate. (d) Assessment of initial in-OR vital signs and treatment as needed prior to procedure start. Hypertension or tachycardia may be treated with mild sedation or cardiovascular medications at the discretion of the anesthesia provider. (e) Mild sedation, anxiolysis, and analgesia may be provided with varying combinations of midazolam, fentanyl, and/or dexmedetomidine in conservative doses. (f) Coughing and gagging may be directly treated by the surgeon with additional lidocaine via a flexible laryngoscope or topical benzocaine to the posterior pharynx and the base of the tongue. (g) IV sedation or IV lidocaine is incrementally added to decrease cough and gag reflex, with medication choices and doses individualized, depending on patient comorbidities and response. (h) Acetaminophen 15 mg/kg up to 1000 mg IV and/or ketorolac 15–30 mg IV may be added for postoperative analgesia, if not contraindicated. 4. Patients should remain NPO post-procedure until the return of strong airway protective reflexes. (a) Two hours after the final airway topicalization, likely performed intraoperatively by the surgeon, is a safe window for resumption of oral intake. (b) Patients and families should be aware of this restriction prior to OR transport, and a reasonable amount of IV fluid should be administered to offset this additional NPO time.

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Key Points • Even minor glottic trauma on initial laryngoscopy and intubation by the anesthesia provider may alter surgical options or lead to an inability to perform the planned procedure. • Patients are positioned on the OR table in a classic sniffing position with the tragus of the ear in line with the sternal notch. This provides optimal alignment of the oral, pharyngeal, and laryngeal axes and improves the glottic view on laryngoscopy. • High-frequency jet ventilation allows ventilation through a laryngoscope with a jet or suction channel or a specially designed small-diameter catheter. This provides an unobstructed surgical field and is an effective method of ventilating patients with high-grade laryngeal stenosis or lesions. • A smooth emergence with minimal to no coughing or bucking is important to prevent glottic trauma and edema. Vigorous coughing can lead to extrusion of the vocal fold injectate, which may completely negate glottic augmentation procedures. • Post-extubation concerns include laryngospasm, glottic edema, glottic or vocal fold dysfunction, and post-­ obstructive pulmonary edema. A collaboration between the surgeon and the anesthesia provider is essential for assessing and treating these issues. • The amount of insulin injected with vocal fold lipoinjections varies with each patient and surgeon, so it is difficult to reliably predict who is at increased risk for postoperative hypoglycemia. • Dexmedetomidine is a selective alpha-2 agonist with unique properties of sedation, anxiolysis, and analgesia with minimal respiratory depression. The main disadvantage is its lack of amnestic effect. Patients will appear comfortable and sedated yet have total recall of intraoperative events. • Patients who have significant comorbidities, do not tolerate in-office injections or laser procedures due to hyperactive gag or anxiety, or those who do not meet vital sign criteria may benefit from having the same in-office procedures performed in the OR with mild sedation and topical airway anesthesia.

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Commentary As an anesthesiologist, these are challenging yet very fulfilling cases that also serve to greatly improve airway management skills.

Bibliography Abdelmalak B, Gutenberg L, Lorenz R, et al. Dexmedetomidine supplemented with local anesthesia for awake laryngoplasty. J Clin Anesth. 2009;21:442–3. Atkins J, Mirza N. Anesthetic considerations and surgical caveats for awake airway surgery. Anesthesiol Clin. 2010;28:555–75. Biro P.  Jet ventilation for surgical interventions in the upper airway. Anesthesiol Clin. 2010;28:397–409. Evans E, Biro P, Bedforth N. Jet ventilation. Continuing Educ Anesth Crit Care Pain. 2007;7:2–5. Hu A, Weissbrod P, Maronian N, et al. Hunsaker Mon-Jet tube ventilation: a 15-year experience. Laryngoscope. 2012;122:2234–9. Jense R, Souter K, Davies J, et  al. Dexmedetomidine sedation for laryngeal framework surgery. Ann Otol Rhinol Laryngol. 2008;117:659–64. Lemyze M, Mallat J.  Understanding negative pressure pulmonary edema. Intensive Care Med. 2014;40:1140. Modanlou S, Marie Giglio N, Carroll T, Pancaro C. Unexplained profound hypoglycemia after vocal fold lipoinjection. AA Case Rep. 2016;6(3):45–7. Putz L, Mayne A, Dincq A. Jet ventilation during rigid bronchoscopy in adults: a focused review. Biomed Res Int. 2016;2016:4234861. Restrepo R, Hirst K, Wittnebel L, Wettstein R. AARC clinical practice guideline: transcutaneous monitoring of carbon dioxide and oxygen 2012. Respir Care. 2012;57(11):1955–62. Rosero EB, Ozayar E, Mau T, Joshi GP. A sequential anesthesia technique for surgical repair of unilateral vocal fold paralysis. J Anesth. 2016;30(6):1078–81. Wilson W, Taubert KA, Gewitz M, et  al. Prevention of infective endocarditis: guidelines from the American Heart Association. Circulation. 2007;116(15):1736–54.

Part II Phonomicrosurgery for Benign Laryngeal Pathology: Principles

Principles of Phonomicrosurgery

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Clark A. Rosen and C. Blake Simpson

12.1

Fundamental and Related Chapters

Please see Chapter 1—“Anatomy and Physiology of the Larynx”, Chapter 4—“Pathological Conditions of the Vocal Fold”, Chapter 9—“Timing, Planning, and Decision-Making in Phonosurgery”, Chapter 14—Perioperative Care for Phonomicrosurgery, Chapter 15—“Management and Prevention of Complications Related to Phonomicrosurgery”, Chapter 18—“Vocal Fold Polyp and Reactive Lesion: Phonomicrosurgery”, Chapter 19—“Vocal Fold Cyst and Vocal Fold Fibrous Mass”, Chapter 20—“Reinke’s Edema”, Chapter 24—“Vascular Lesions of the Vocal Fold: Phonomicrosurgery”, and Chapter 25—“Vocal Fold Scar and Sulcus Deformities of the Vocal Fold” for further information.

12.2

Introduction

Phonomicrosurgery encompasses a variety of operations that have the primary goal of improving voice quality. These are elective operations that involve precision microsurgical removal of benign vocal fold pathology—most often from the subepithelial space of the vocal fold. The surgical procedures and principals are based on vocal fold physiology, specifically Hirano’s cover-body theory of vocal fold vibration (see Chapter 1—“Anatomy and Physiology of the Larynx”). Given the importance of the interaction between the epithelium– superficial layer of the lamina propria (cover) and the underlying deep layer of the lamina propria and muscle (body),

C. A. Rosen (*) UCSF Voice & Swallowing Center, Department of Otolaryngology-Head & Neck Surgery, University of California, San Francisco, San Francisco, CA, USA e-mail: [email protected] C. B. Simpson Department of Otolaryngology—Head and Neck Surgery, University of Alabama at Birmingham, Birmingham, AL, USA e-mail: [email protected]

phonomicrosurgery was born and has evolved to advocate for the minimal disruption to the normal microarchitecture of the vocal fold while removing dysphonia-inducing pathology. The overarching goal is to limit dissection to the most superficial plane possible and maximize epithelial and lamina propria preservation. The latter tenet is important to facilitate primary wound healing versus secondary wound healing. This is theorized to allow maximal functional recovery (vocal fold mucosal vibration and voice quality) after surgery.

12.3

Surgical Indications and Contraindications

Phonomicrosurgery is an elective surgery, and thus, pressure should not be placed on the patient to proceed with surgery. The risks and benefits of the surgery should be detailed to the patient, and, most importantly, a realistic and thorough evaluation of the patient’s functional voice limitations and abilities (speech and singing) should be reviewed. Often, this review process is conducted over several weeks and involves the patient, physician, family members, a speech-language pathologist, and possibly a singing voice specialist. When all nonsurgical treatment modalities have been exhausted and significant vocal functional limitations have been identified, the setting is deemed appropriate for proceeding with phonomicrosurgery (see Chapter 9—“Timing, Planning, and Decision-Making in Phonosurgery”). Important preoperative measures before phonomicrosurgery include: • Avoiding aspirin, nonsteroidal anti-inflammatory medications, or other anticoagulation medications • Avoiding significant vocal use, abuse and misuse immediately before surgery • Avoiding operating during the premenstrual period of a woman’s menstrual cycle, due to the concern of  edema occurring at this time as well as some increased fragility of the microvasculature of the vocal fold

© Springer Nature Switzerland AG 2024 C. A. Rosen, C. B. Simpson, Operative Techniques in Laryngology, https://doi.org/10.1007/978-3-031-34354-4_12

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Voice therapy prior to phonomicrosurgery  (one to two sessions) is extremely important in the preparation for phonomicrosurgery for a variety of reasons: • Psychological preparation for surgery • Education regarding postoperative voice rest and voice use • Modification of and improvement in improper speaking techniques and habits • Laying the foundation for postoperative voice therapy, both psychologically and from a behavioral perspective Voice therapy prior to phonomicrosurgery stresses to the patient the importance of changing inappropriate vocal techniques and implementing healthy voice behaviors in the postoperative period. Prior to phonomicrosurgery, the patient must realize that he/she will be on voice rest and reduced voice use for a variable period (from 3 to 30  days). This is to ensure that the patient has adjusted his/her voice use to be compliant with the surgeon’s voice rest and reduced voice use limitations. Preoperative consent for phonomicrosurgery should involve the risks of general anesthesia, temporal mandibular joint injury, dental injury, and injury to the lingual nerve. The latter has been shown to be predominantly temporary in nature and lasts for 2 weeks on average, with most symptoms resolving within 1  month. A discussion regarding postoperative voice quality after phonomicrosurgery should be taken seriously and personally communicated by the surgeon. The discussion should involve the small but real risk of either no improvement in the voice quality (~1–2% incidence) or a reduction in vocal function or voice quality (~1–2% incidence). The surgeon should review the patient’s most recent stroboscopy (the last exam should have been within the previous 15–20 days) prior to phonomicrosurgery. The surgeon's review of the stroboscopy should be carried out on the day of surgery or 1–2 days before the surgery. The optimal situation for this preoperative stroboscopy review is to have the stroboscopic examination available for review in the operating room immediately before and during the procedure. This allows the surgeon to correlate the stroboscopic findings with the surgical findings and make important decisions on the location of the pathology, the location of placement of incisions, and the degree of dissection and excision using the preoperative stroboscopy findings and the operative findings as guides. The equipment/vendors utilized by the authors are listed below; however, this is by no means a complete list of all the vendors who make these products: Endocraft (Boston, MA), Karl Storz (Culver City, CA), Instrumentarium (Montreal, Quebec, Canada), Integra LifeSciences (Princeton, NJ), Pilling Surgical (Research Triangle, NC), and Richard Wolf (Vernon Hills, IL).

12.4 Equipment for Phonomicrosurgery Specialized laryngoscopes are required for phonomicrosurgery. The larger the laryngoscope, the better it is for phonomicrosurgery, given that this results in significantly improved

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exposure and access to the surgical site(s). Multiple large and specialized laryngoscopes exist, and a wide variety of laryngoscopes are necessary to manage all different types of phonomicrosurgical lesions and procedures. Specialized laryngoscopes for individualized laryngoscopy needs are important, e.g., a posterior commissure laryngoscope is required for difficult posterior glottic exposure and an Ossoff-Pilling laryngoscope is needed for microlaryngeal surgery in patients with restricted upper aerodigestive tract anatomy (Table 12.1). Table 12.1  Standard microlaryngeal instrumentation A high-quality operating microscope with a 400-mm lens on a variable focal length operating microscope A large-bore laryngoscope (largest diameter possible) Examples include: • A universal modular glottiscope (Endocraft, Warwick, RI) • A Sataloff laryngoscope (Integra LifeSciences, Princeton, NJ) • A Lindholm laryngoscope (Karl Storz, Culver City, CA) • An operating laryngoscope for anterior commissure (model #8458.011, Richard Wolf, Vernon Hills, IL) Specialized laryngoscopes for unique situations • An Ossoff-Pilling laryngoscope for difficult exposure (Teleflex, Morrisville, NC) • A posterior commissure laryngoscope (Teleflex, Morrisville, NC) Suspension system • Boston University suspension (Teleflex or Endocraft) (see Fig. 12.1) • Fulcrum suspension: Lewy suspension and a table-mounted Mayo stand (see Fig. 12.2) An operating chair with arm supports (see Fig. 12.3) Instrumentation (Karl-Storz, Integra LifeSciences, Instrumentarium) • Specialized blunt microelevators (see Fig. 12.4) • Microcup forceps (1–2 mm in diameter) (see Fig. 12.5) • Up-angled and right and left micro-ovoid cup forceps (see Fig. 12.6) • Microscissors (see Fig. 12.7) • Curved alligator forceps (left and right) (see Fig. 12.8) • Curved (left and right) • Up angled • Straight alligator forceps • Microlaryngeal suctions (3, 5, and 7 French) • Triangular (Bouchayer) forceps (left and right) (see Fig. 12.9) • A microlaryngeal knife (sickle or spear) Miscellaneous equipment • Cotton pledgets— (multiple sizes: 0.5 × 2 cm, ½ × ½ inch, and ¼ × ¼ inch) • 1:10,000 epinephrine • A Velcro strap or cloth/silk tape 1 inch in width • A mouth guard (maxillary ± mandibular) • Acrylic mouth guard—custom-made by dentist • An Aquaplast nasal split—requires molding (see Fig. 12.10) • A plastic “anesthesiologist” tooth guard, reinforced with layers of cloth tape (see Fig. 12.11) • High-density foam (edentulous patients only) (see Fig. 12.12) Optical telescope • Diameter: 4–5 mm, length: 20 cm or more • 0, 30, and 70° telescopes A microdebrider—a skimmer blade (Integra LifeSciences, Princeton, NJ) A subepithelial infusion needle (25 or 27g) • An orotracheal injector (Integra LifeSciences, Princeton, NJ) with disposable 27-g needles A small-diameter, extended-length endotracheal tube (5.0 or 5.5) designed for microlaryngoscopy A tracheal jet ventilation tube (Hunsaker jet ventilation tube)

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Fig. 12.1  A gallows-type suspension device. A patient positioned for phonomicrosurgery. The neck flexion, head extension, and angle of the Velcro strap positioning the larynx into the optimal viewing path of the laryngoscope should all be noted

Fig. 12.3  An alternative method of supporting the surgeon’s arms, using a padded Mayo stand

Fig. 12.2  A fulcrum-type suspension device (a Lewy apparatus suspended from a table-mounted Mayo stand)

The core set of instruments utilized for phonomicrosurgery include specialized blunt microelevators, cup forceps, scissors, curved alligators, and small suctions (3, 5, and 7 French). These elevators are often used to palpate the submucosal pathology at the start of surgery. In addition, a specialized set of instruments have been developed for microflap retraction. These are called triangular forceps or Bouchayer forceps. Most of the instruments described below are available from several manufacturers of phonomicrosurgery equipment, including Integra LifeSciences (Princeton, NJ), Karl Storz (Culver City, CA), and Instrumentarium (Montreal, Quebec, Canada). The key microlaryngoscopy instruments utilized for phonomicrosurgery involve:

• Specialized blunt microelevators (Fig. 12.4) –– The microelevators should be blunt and have several different angles and sizes to allow the surgeon to work at various angles in different positions within the vocal fold, specifically, when dissecting the vocal fold lesion off the overlying microflap. • Microcup forceps (Fig. 12.5) –– Several small special cup forceps have been developed to facilitate several specific situations that are encountered in phonomicrosurgery. These forceps have a sharp cutting edge but an extremely limited cutting surface, with only the most distal 180° of the forceps cut. The most useful microcup forceps is angled-up and has a 1-mm diameter. • Micro-ovoid cup forceps (Fig. 12.6) –– Ovoid-shaped microcup forceps are also essential for removing small pieces of pathological mucosa and papilloma (see Chapter 18—“Vocal Fold Polyp and Reactive Lesion: Phonomicrosurgery”  and  see Chapter 23—“Surgical Treatment of Recurrent Respiratory Papillomatosis of the Larynx”). This instrument comes in two sizes and is valuable for precision removal of small amounts of tissue. These instruments are made by Instrumentarium (Rusty and Baby Rusty).

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Fig. 12.4  Angled elevators for phonomicrosurgery Fig. 12.5  Microcup forceps (1 mm), with the cutting surface limited to a distal 180°

Fig. 12.6  Micro-ovoid cup forceps (“Rusty” instruments)

Fig. 12.7  Microscissors, curved and angled up

• Microscissors (Fig. 12.7) –– The most commonly used microscissors are right- and left-curved as well as “straight up” or angled scissors. These scissors should be maintained at all times to appropriate surgical precision and sharpness, given that they are the primary cutting tools for phonomicrosurgery. • Curved alligators (Fig. 12.8) • Epinephrine (1:10,000) and cotton pledgets (0.5 × 2 cm, ½ × ½ inch, and ¼ × ¼ inch) • Microlaryngeal suctions (3, 5, and 7 French) • Triangular forceps or Bouchayer forceps (for microflap retraction) (Fig. 12.9) –– These instruments are designed to retract the microflap to allow vocal fold visualization and dissection while minimizing trauma to the microflap. They are made in a variety of sizes and designs for different situations.

• A sickle knife (or a spear-shaped knife) –– These knives tend to become dull very quickly, and, thus, it is recommended that this knife be replaced with every case or at least on a highly frequent basis. A dull knife can result in tearing of the mucosa and can significantly limit the efficacy of phonomicrosurgery. –– Fine gauge injection needle for epinephrine and steriod injection. Orotracheal injector (Integra LifeScience) uses a disposable 27g needle. An alternative injector can involve a butterfly needle with the wings of the needle removed and a cup forceps is used to pass needle down laryngoscope for injection. • A microdebrider –– A microdebrider is a powered instrument that provides simultaneous suction and cutting activity and is used for rapid removal of exophytic lesions in the larynx such as recurrent respiratory papillomatosis (RRP) (see Chapter 23—“Surgical Treatment of Recurrent

12  Principles of Phonomicrosurgery

Fig. 12.8  Curved alligators for phonomicrosurgery

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Fig. 12.9  Triangular (Bouchayer) forceps

Fig. 12.10  Aquaplast/Thermoplast sheeting used to form a dental protective device Fig. 12.11  A tooth protector fashioned from a plastic tooth guard and layers of cloth tape

Fig. 12.12  High-density foam for protecting the alveolar ridge in an edentulous patient during suspension laryngoscopy

Respiratory Papillomatosis of the Larynx”). There are two different types of cutting blades: Conservative (i.e., a “skimmer blade”) A conservative blade is the most commonly used for laryngeal surgery. The advantages of a microdebrider are expedient removal of a significant amount of laryngeal pathology, less pain after surgery (compared to that of a CO2 laser), less expensive than laser, and potentially even safer, given the risks of laser laryngeal surgery. The disadvantages of microdebrider for laryngeal surgery include the powered instrument shaft is relatively large, and sometimes visualization can be limited, and the risk that the powered instrument may be too strong and injure delicate subepithelial tissues of the vocal fold or other endolaryngeal structures.

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Aggressive (i.e., “tri-cut”) This blade should be used with great care, given how quickly it can remove both disease (RRP) and normal structures. The majority of laryngeal diseases do not need the level of aggressive surgical removal that this blade offers. This blade may be helpful in extremely severe keratotic disease that is not able to be removed with a skimmer blade. Suspension of a laryngoscope is a fundamental aspect of phonomicrosurgery. A laryngoscope can be held in a fixed and stable position using two basic devices, namely, a gallows suspension device and a rotation/fulcrum device. The gallows suspension laryngoscope is favorable, given that there is a more appropriate upward vector of the laryngoscope, which can provide optimal exposure of the endolarynx with minimal risk of dental injury, especially to the maxillary teeth. This device is not the most common due to traditional and historical use of rotation/fulcrum devices (i.e., Lewy suspension). Long Hopkins rod telescopes with various visualization angulations are an essential component of phonomicrosurgery. Rarely is a surgery performed utilizing these telescopes, but these telescopes are used to provide the surgeon with a “three-dimensional visualization” of the vocal folds and their related pathology. The 30° and 70° telescopes, which are approximately 4–5  mm in diameter and 30-cm long, should be utilized immediately prior to phonomicrosurgical incision and also during and after phonomicrosurgery to ensure that all appropriate pathologies have been removed. These angled telescopes are readily available in most operating rooms, given that they are regularly used for cystoscopy. Telescopes used for sinus surgery are too short to be effectively used for laryngeal imaging. The microscope used for phonomicrosurgery should be of the highest quality and provide the surgeon with stable visualization of the endolarynx. There should be significant adjustment as well as control over many different articulated angles of the microscope. This microscope should be the same as that used for precision otologic procedures such as stapes surgery and other middle ear operations. A microscope that is routinely used for the placement of pressure-­ equalizing tubes is typically not appropriate for phonomicrosurgery. Furthermore, the microscope should have the capability to be compatible with the CO2 laser micromanipulator attachment and the potassium–titanyl– phosphate (KTP) laser shutter. The typical length of the lens used in the surgical microscope for phonomicrosurgery is 400 mm. This allows adequate space between the proximal end of the laryngoscope and the microscope for handheld instruments to be used for phonomicrosurgery. Many recent models of operating microscopes now have variable focal length designs. This allows the surgeon to use a range of focal lengths with varying levels of magnification. These devices are excellent for phonomicrosurgery, but the surgeon must keep in mind the direct relationship of focal length with

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maximum magnification. The longer the focal length, the less maximum magnification afforded. Thus, when using a variable focal length operating microscope for phonomicrosurgery, it is best to use as short a focal length as possible to allow the highest level of magnification to optimize surgical precision. Typically, this involves using a focal length between 375 and 415 mm. Another important feature of the surgical microscope is articulated eyepieces; these allow for optimal surgeon ergonomics, which is important for lengthy phonomicrosurgery cases and for the long-term health of the phonomicrosurgeon (see Chapter 13—“Ergonomics of Phonomicrosurgery”). Lasers have a limited role in phonomicrosurgical procedures (see Chapter 16—“Principles of Laser Microlaryngoscopy”). The most commonly used laser is the CO2 laser. The CO2 laser with a micromanipulator can be used for making vocal fold incisions or removing free-edge lesions. However, there are no distinct advantages to using this laser in this setting, and the risks of thermal injury and costs of the instrument outweigh any potential benefits. The majority of phonomicrosurgery can and should be performed with “cold-steel” instrumentation. Recently, pulsed dye lasers (PDLs) and pulsed KTP lasers have been advocated for phonomicrosurgery. However, their benefits over cold-­steel surgery have not yet been demonstrated, but they may be complementary when dealing with vascular lesions associated with other vocal fold lesions (cysts, polyps, etc.). The CO2 laser does offer an “instrument-free” approach to surgery of the vocal folds, and, in an extremely small, crowded surgical space, this can be an advantage. However, for most phonomicrosurgical situations, this is not a major problem, and, thus, the CO2 laser is rarely indicated for this reason alone.

12.5 Phonomicrosurgical Procedures, Techniques, and Methods 12.5.1 Anesthesia A working relationship between the phonomicrosurgeon and the anesthesia colleague(s), based on mutual respect, communication, and teamwork, is essential for a successful phonomicrosurgery (see Chapter 10—“Anesthesia and Airway Management for Laryngeal Surgery: Surgeon’s Perspective”). Phonomicrosurgery involves general anesthesia, and complete muscle relaxation should be implemented after the induction of general anesthesia and continuously monitored throughout the surgery. Preoperatively, one should administer intravenous (IV) steroids (10–20 mg dexamethasone) and glycopyrrolate (unless contraindicated). Placement of the endotracheal tube is extremely important, given that a misplaced or traumatic placement of the endotracheal tube can cause injury to the vocal folds and may result in cancellation of surgery and/or injury to the vocal folds. The endotracheal tube should be placed under completely controlled conditions, and, ideally, no stylet should be used during direct

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laryngoscopy intubation. Furthermore, the otolaryngologist should be present during the intubation to monitor the situation and be available to assist in intubation as required. In certain cases of difficult laryngeal exposure, a GlideScope (Verathon, Bothell, Washington) or C-MAC (Karl Storz) videolaryngoscope can be used by the anesthesiology team to facilitate visualization by the entire surgical team during intubation. Similarly, controlled extubation at the end of phonomicrosurgery is another important aspect of the necessary teamwork between the anesthesia team and the phonomicrosurgeon. Extubation should be performed in a controlled manner, and all measures should be used to reduce the likelihood of the patient coughing after extubation. The ventilation options for phonomicrosurgery are endotracheal intubation, jet ventilation, or apneic methods. The large majority of phonomicrosurgery is best performed using endotracheal intubation with a small (5.0 or 5.5), specialized endotracheal tube. This provides a still operating field and complete control of the airway. Sometimes the endotracheal tube can be in the way of the surgical procedure and may need to be repositioned or removed in its entirety. Jet ventilation for phonomicrosurgery should be performed only on an as-needed basis and is best done when the jet ventilation is delivered from a small jet ventilation catheter (Hunsaker jet tube) placed in the mid-tracheal region. Tracheal jet ventilation is preferred over supraglottic jet ventilation, given that the former provides the surgeon with less vibration and desiccation of the vocal fold tissues while phonomicrosurgery is being performed and allows end-tidal CO2 monitoring. Appropriate and successful phonomicrosurgery can rarely be performed using an apneic technique for anesthesia, given that the time between ventilations is too short for most phonosurgical procedures. An exception to this may be for bronchoscopy (flexible or rigid), vocal fold injection, and diagnostic laryngoscopy prior to the placement of an endotracheal tube. High flow nasal oxygen (THRIVE) can supplement during apnea anesthesia and expand the periods of apnea.

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Fig. 12.13  The optimal patient position for suspension laryngoscopy (the neck flexion and head extension should be noted)

Fig. 12.14  An alternative method of positioning a patient without the use of an articulated head of bed (the neck flexion due to the pillow underneath the head should be noted)

12.5.2 Patient Position Patients undergoing phonomicrosurgery are placed in a supine position on the operating room table. The optimal head and neck position for exposure of the endolarynx with the laryngoscope is neck flexion on the body and the head extension on the neck. A shoulder roll typically places the patient in a suboptimal position for proper laryngoscope placement (neck extension) and thus should “not” be used. Neck flexion can be achieved using an articulated head of the operating table and displacing it upward (i.e., lifting the head). Head extension on the neck is facilitated by the surgeon during laryngoscopy and secured with the suspension device (Fig.  12.13). Another

method of obtaining neck flexion is to use a pillow under the head to flex the neck on the body (Fig. 12.14).

12.5.3 Laryngoscope Placement Laryngoscope placement is crucial to the success of phonomicrosurgery and can be quite daunting to the novice phonomicrosurgeon. An adequate amount of time and patience should be allocated for this important step, ensuring that a proper head and neck position during laryngoscopy placement is a key step, as described above. The overall goal is to place the largest-

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Fig. 12.15 Laryngoscope advancement causing “folding” of the epiglottis

Fig. 12.17  Placement of a laryngoscope into the endolarynx below the non-folded epiglottis while the endotracheal tube is positioned anteriorly with the nondominant hand’s finger (it should be noted that initially the laryngoscope will be posterior to the endotracheal tube)

diameter laryngoscope into the endolarynx. A frequent impediment to this goal is the inward folding of the epiglottis (Fig. 12.15). When this occurs, the potential space to place the distal aspect of the laryngoscope into the endolarynx is significantly reduced and the epiglottis can be traumatized (Fig. 12.16). With the use of a large-diameter laryngoscope, the positioning of the laryngoscope can be quite difficult. Instead of aborting the use of the large-­diameter laryngoscope, patience and persistence should be judiciously applied. As the laryngoscope is placed into the oral cavity, the lips and tongue should be retracted with the nondominant hand.

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Fig. 12.16  A “folded” epiglottis above the laryngoscope limits space for the placement of a large-diameter laryngoscope

The laryngoscope is then slid along the ventral surface of the tongue and advanced down toward the base of the tongue and posterior pharyngeal wall. At this juncture, there are a variety of techniques to place the laryngoscope under the epiglottis without folding or traumatizing the epiglottis. First, if there is adequate space, then the laryngoscope can be passed under direct vision underneath the epiglottis and advanced into the endolarynx. This direct approach may result in the folding of the epiglottis when attempted with a large-diameter laryngoscope (Fig.  12.16). At this stage, it best to use one of the other laryngoscope placement techniques (see below) instead of resorting to the use of a smaller laryngoscope. The second option for laryngoscope placement is to place the laryngoscope between the posterior pharyngeal wall and the endotracheal tube and to continue advancing the laryngoscope along the posterior pharyngeal wall (underneath the endotracheal tube). Once the laryngoscope is at the approximate level of the endolarynx infraglottically, it can be drawn anteriorly into the endolaryngeal space, thus allowing the endotracheal tube to slip around the side of the laryngoscope and be positioned in the posterior glottis. Alternately, the endotracheal tube can be manually displaced around the side of the laryngoscope, into a posterior position. The third method to place a large-diameter laryngoscope into the endolarynx without damage or malposition of the epiglottis is to place the nondominant hand’s index finger into the oral cavity and oropharynx toward the endotracheal tube and pick the endotracheal tube up off the posterior pharyngeal wall. With the endotracheal tube secured underneath the index fingertip, the laryngoscope can then be advanced along the posterior pharyngeal wall and drawn up into the endolarynx (Fig. 12.17). Using this technique, the endotra-

12  Principles of Phonomicrosurgery

Fig. 12.18  Anterior deflection of the endotracheal tube with the nondominant hand to allow placement of the laryngoscope into the endolarynx

Fig. 12.20  Cup forceps placed outside the laryngoscope to control the position of the epiglottis, allowing placement of the laryngoscope into the endolarynx without “folding” of the epiglottis

cheal tube may be initially positioned anterior to the laryngoscope. When the laryngoscope is successfully placed in the endolarynx but the endotracheal tube is anterior to the laryngoscope, the endotracheal tube can be drawn gently and carefully down into the more appropriate posterior glottic position, without too much difficulty, using the upward pressure of the suspended laryngoscope or the nondominant hand’s index finger (Fig. 12.18). The fourth technique for the placement of a large-­diameter laryngoscope in a patient with a difficult epiglottic anatomy

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Fig. 12.19  A laryngoscope positioned above the epiglottis, which is resting directly on the endotracheal tube

(i.e., large, floppy) starts with positioning the laryngoscope immediately above the tip of the epiglottis (Fig. 12.19). With this visualization, large cup forceps are passed outside the laryngoscope, down toward the proximal tip of the laryngoscope and used to firmly grab the tip of the epiglottis. With firm control of the epiglottis, the cup forceps can be used to pull or direct the epiglottis in the anterior direction (Fig.  12.20). As the epiglottis is being held anteriorly, the laryngoscope is then advanced into the endolarynx on top of the endotracheal tube. Once the laryngoscope is successfully placed in the endolarynx, the forceps are opened and the epiglottis is released. The fifth option for laryngoscope placement involves placement of a temporary suture through the epiglottis. A large-diameter laryngoscope is positioned by hand or suspension above the epiglottis. Working through the microscope, a 4.0 silk suture (CV 23 needle (taper), Covidien) is placed through the tip of the epiglottis, and the two ends of the suture are brought out through the laryngoscope. The laryngoscope is completely removed from the oral cavity and then replaced above the epiglottis, with the suture through the epiglottis being kept external to the laryngoscope. Tension can be applied to the epiglottic suture to control and stabilize the epiglottis as the laryngoscope is passed underneath it into position. Once a good position of the laryngoscope is achieved, the suture is removed from the epiglottis. (Alternatively, the suture can be removed at the end of the case.) The optimal position of the laryngoscope within the endolarynx is determined by the vocal fold pathology and pending surgical procedure. However, in general, the laryngoscope should be positioned immediately above (superior to) the vocal fold pathology, specifically resulting in retrac-

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tion of the false vocal fold tissues. Care should be taken to avoid the laryngoscope contacting the superior surface of the vocal fold, given that this will significantly alter the anatomic orientation and nature of the vocal fold and often distort the vocal fold pathology.

12.5.4 Suspension Device A gallows suspension device (Fig. 12.1), if used, should be positioned to provide upward and slightly forward (caudal) suspension of the laryngoscope in the endolarynx. This special angulation of the laryngoscope will provide optimal laryngoscopy visualization and cause minimal adjacent tissue injury or damage. For a rotation/ fulcrum laryngoscope device holder (a Lewy laryngoscope holder with a table-­mounted Mayo stand; Fig. 12.2), it is of the utmost importance to remember to provide special care and attention to the maxillary teeth as the laryngoscope holder is put into place. This is especially important given that as the fulcrum holder is adjusted, each amount of upward rotation at the distal tip of the laryngoscope results in an equal amount of downward pressure at the proximal aspect of the laryngoscope on the maxillary alveolar ridge.

12.5.5 Dental/Alveolar Arch Protection

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dentition, then a dental protector for these teeth may be fashioned as well. Aquaplast/Thermoplast sheeting is used to form a dental protective device (Thermosplint singles— Medtronic ENT). A medium or large sheeting is typically used (Fig. 12.10). The backing is removed from the sheet, and it is placed in a Styrofoam cup filled with hot water that is near boiling temperature. Warm water does not heat up the sheet enough to mold it properly. Once the sheet turns clear, it is removed from the water and folded in half lengthwise (Fig. 12.21). It is then molded to the maxillary dentition, taking care not to thin the material excessively. As it cools, the sheet gradually hardens. Pouring ice-cold water over the sheet during the molding process hastens this process (Fig. 12.22). If Aquaplast/Thermoplast is not available, then a tooth protector can be fashioned using a standard thin plastic tooth guard commonly found in anesthesiology carts and reinforcing it with multiple layers of cloth tape (Fig. 12.11). For patients with an edentulous maxilla, the best way to protect the mucosa and the underlying alveolar ridge from laryngoscope placement and suspension injury is to place a small, high-density foam pad between the laryngoscope and the alveolar ridge. This foam padding is present in most operating rooms in the form of a headrest or pillow material (Fig. 12.12).

12.5.6 External Counterpressure

Dental and alveolar ridge protection prior to insertion of a laryngoscope is important. Maxillary dentition, especially the central and lateral incisors, is at the highest risk for injury. In all cases, a maxillary dental protector should be placed. If there is excessive contact with the mandibular

A Velcro strap or cloth/silk tape can be applied to the external neck (in the area of the cricoid or trachea) in a downward and slightly cephalad vector to improve the endolaryngeal exposure on an as-needed basis (Fig. 12.23). The surgeon should look down the laryngoscope while applying external counterpressure to judge the location and

Fig. 12.21  The material is heated in hot water until it turns clear. It is then removed and folded in half lengthwise

Fig. 12.22  The material is molded over the maxillary dentition until hardened

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Fig. 12.23  A Velcro strap applied to the anterior neck region (near the cricoid) to optimize vocal fold visualization during suspension laryngoscopy

the amount of the external counterpressure required. A small amount of gauze or a foam pad can be positioned between the tape or strap and the neck skin to prevent any injury to the overlying skin of the larynx (Fig. 12.1). It is extremely important that the surgeon remembers this type of external counterpressure, which is often essential to optimal exposure of the endolarynx, as it puts the patient at risk if the patient were to move unexpectedly as the anesthesia wears off. If this occurs, then the first duty of the surgeon is to release the external counterpressure and, second, take the patient out of suspension laryngoscopy. In addition, it is imperative to release the tension during intraoperative repositioning of the laryngoscope.

12.5.7 Telescopic Evaluation of Vocal Fold Pathology

Fig. 12.24  Visualization of vocal fold pathology during suspension laryngoscopy with angled telescopes

Using the 0o, 30o, and 70° (and as needed, 120°) telescopes for visualization of the endolarynx in a “three-dimensional” manner is of great value. This is done after the laryngoscope is suspended. This allows for unique visualization of the vocal fold pathology, photodocumentation, and surgical planning (Fig. 12.24). Specifically, decisions are often made

about the optimal location for an incision when evaluating the vocal fold pathology, specifically when using the 30 and 70° angled telescopes. In addition, these telescopes provide great visualization of the ventricles, subglottis, and anterior and posterior commissure.

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12.5.8 Operating Microscope and Surgeon Ergonomics After suspension of the laryngoscope and telescopic examination, the surgical microscope is brought into position and attention should be drawn to the position of the laryngoscope in relation to the microscope and the surgeon. Optimal hand control of instrumentation during phonomicrosurgery occurs when the forearms can be supported with a stable device, such as an operating room chair with arm supports. The wrists are the best location for precise control, and, thus, some type of surgical support should be identified (an ophthalmology or plastic surgery operating room chair with arm supports or a Mayo stand) that will allow the steadiest and stable hand and wrist motions while supporting the arms at the level of the forearms (Fig.  12.25). Patient positioning should allow the surgeon’s upper arms to be held in a vertical position, with the elbows and hands as low as possible to the surgeon’s lap. An alternative to these custom surgical chairs is to use a Mayo stand with pillows/foam padding. The Mayo stand is placed between the surgeon and the head of the bed (Fig. 12.3). Paying attention to the surgeon’s neck, head, and back positions during the surgical procedure is important for his/ her long-standing neck and back health. Often, to facilitate optimal phonomicrosurgery ergonomics, the operating room table should be placed in the reverse Trendelenburg position. This brings the laryngoscope lower—into the surgeon’s lap—and the eye pieces of the surgical microscope should be utilized to allow the surgeon to sit with his/her back completely straight and upright, avoiding expressive neck flexion (See Chapter 13—“Ergonomics of Phonomicrosurgery”) (Fig. 12.25). Binocular vision at high-power magnification must be achieved at all aspects of the procedure. This will require minor but important adjustments of the position of the micro-

Fig. 12.25  Proper support of surgeon’s arms for phonomicrosurgery

C. A. Rosen and C. B. Simpson

scope and laryngoscope to ensure that the viewing access of the microscope is perfectly coaxial with the longitudinal aspect of the laryngoscope, thus allowing binocular vision. This is an extremely important component of phonomicrosurgery, and it should not be overlooked. A novice phonomicrosurgeon will initially struggle with this task, but patience and practice will allow success. The majority of phonomicrosurgical procedures should be carried out using the microscope’s highest magnification setting.

12.5.9 Microflap Approach to Submucosal Pathology The microflap approach to a submucosal pathology is a key aspect of most phonomicrosurgery operations. The core principles of the microflap approach to a submucosal pathology include: • Making an incision through the epithelium at the closest possible location to the submucosal pathology • Minimally disrupting the tissue surrounding the vocal fold pathology • Staying as much as possible in the most superficial plane • Preserving the overlying normal mucosa (the epithelium plus superficial lamina propria) Prior to surgery on the vocal fold, careful, intentional and thoughtful vocal fold palpation should be performed (bilaterally). This can be done with a small guage suction or the back of a curved instrument. This provides the surgery with tactile feedback of the lesion(s) at hand and improves localization. At this point, if one is confident that the lesion at hand is a one of the following: SE-cyst, lig-Cyst, SE-fibrous mass, lig-fibrous mass and a microflap approach is planned, a sub-epithelial injection of 1:10,000 epinephrine can be performed. This injection is usually done with an orotracheal injector (Integra LifeSciences). The injection is done in an area adjacent to the lesion, usually 1 mm posterior and lateral. This creates a sub-epithelial plane for surgical dissection and enhances hemostasis for the microflap. There are multiple descriptions of various forms of microflaps, specifically lateral microflaps, medial microflaps, and mini-microflaps. Over the years, many of these microflap approaches have merged into a single, philosophical microflap approach to submucosal pathology, which is described below. The incision for a microflap should be directly overlying or immediately lateral to the vocal fold pathology. This results in minimal disruption of the normal adjacent vocal fold mucosa. After the vocal fold pathology is palpated and an incision is planned, an incision is made with a sharp sickle knife. It is important to note that the tip of the sickle knife

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should be used to penetrate the epithelium and then it can be drawn slightly superiorly, tenting up the epithelium as the incision is made in an anterior or posterior direction (Fig. 12.26). This prevents the sickle knife from accidentally causing any type of injury to the submucosal pathology or deep vocal fold tissues. After the incision is made, the vocal fold pathology may be able to be palpated and directly visualized through the incision and a small curved elevator can be used to begin the elevation of the microflap in the plane between the vocal fold pathology and the overlying epithelium (i.e., medial to the lesion). This plane is the single most difficult step of phonomicrosurgery, and it should be performed with great patience and caution. It is often the easiest to initiate and develop this plane anteriorly and posteriorly to the vocal fold lesion. Often, various angulated or curved elevators will be required to perform this aspect of the procedure, given that at the very start of the development of the microflap, the surgeon initially works on the upper lip of the free edge of the vocal fold medially. Then, as the microflap is carefully elevated and dissected from the submucosal pathology, the surgeon works in the exact opposite direction on the inferior lip of the vocal fold laterally, and, thus, different curved elevators are often required to work in different directions, especially to ensure minimal risk of microflap penetration or injury. Once a plane is developed anteriorly and posteriorly to the lesion, a careful submucosal dissection with a small, fine blunt elevator (curved or angled) is performed to complete the elevation and create the microflap (Fig. 12.27). There may be

instances in which small, microcurved scissors need to be used to release fibrous bands off the overlying microflap in adherent areas of the submucosal pathology or, in a similar manner, when the submucosal pathology is adherent to the deeper aspects of the vocal fold in the area of the vocal ligament (see Chapter 19—“Vocal Fold Cyst and Vocal Fold Fibrous Mass”). Hemostasis is extremely important, and if bleeding causes an obstruction of visualization, then the surgery should be temporarily stopped and epinephrine (1:10,000)-soaked, small cotton pledgets should be applied to quickly and successfully provide surgical hemostasis without much difficulty. Suctioning blood and secretions from this area should be performed with a 3-French suction, usually without covering the thumb port. Great care should be taken not to tear or fenestrate the microflap as it is carefully elevated off the submucosal pathology. The majority of benign vocal fold submucosal pathologies are located in the immediate subepithelial plane and is often, to varying degrees, adherent to the overlying epithelium. This is the case in approximately 80–90% of cases; however, there will be situations in which the pathology is not adherent to the overlying microflap and, instead, is located deeper within the vocal fold (in the area of the vocal fold ligament) (Fig.  12.28). This is true for ligamentous vocal fold cysts and fibrous masses (see Chapter 4—“Pathological Conditions of the Vocal Fold”). When these pathologies are encountered, the surgeon will notice that the microflap elevation is quite easy; however, the deeper aspect of the dissection,

Fig. 12.26  A microflap incision placed lateral to the lesion with the epithelium tented up by a sickle knife

Fig. 12.27  Elevation of the microflap off the vocal fold lesion beneath

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Fig. 12.28  An elevated microflap reveals that the pathology (fibrous mass) is on the vocal ligament and not in the subepithelial space

creating a plane between the vocal fold pathology and the vocal ligament, is quite difficult. In this situation, great care should be taken to use either a blunt dissection technique or microscissors to release the adherent bands between the vocal fold ligament and the pathology, always erring on the side of the pathology (in a superficial manner). After the superficial and deep planes around the submucosal pathology are elevated, there may be some additional connections to the vocal fold pathology within the vocal fold anteriorly and posteriorly. These bands can be released with blunt dissection or microcurved scissors. This allows the submucosal pathology to be removed and sent for pathological examination. The microflap is then redraped with a curved elevator (Fig. 12.29). It is often helpful to place an epinephrine (1:10,000)-soaked cottonoid over the operative site for 1–2 min to reduce edema before making further surgical decisions. After the microflap is redraped, palpation of the vocal fold should be performed to determine whether there is any residual submucosal pathology that can be palpated and subsequently require removal. The free edge of the vocal fold should be straight after the pathology is removed; if not, further investigation into either the undersurface of the microflap or the deeper aspect of the vocal fold should be performed. If there is any residual pathological tissue such as a fibrous material or a scar, then this tissue should be removed in a conservative and reasonable manner. This material can be removed with a microelevator or microcup forceps. Extreme care is required at this juncture of the surgery because overly aggressive removal of this material can result in significant scar formation and in a per-

C. A. Rosen and C. B. Simpson

Fig. 12.29  A redraped microflap after removal of the vocal fold lesion. Coaptation of the mucosa at the incision site and the smooth free edge of the vocal fold should be noted

manent deformity of the free edge of the vocal fold. At the completion of the vocal fold lesion(s) excision, the free edge of each vocal fold should ideally be completely straight without exophytic mucosal tags and without a soft tissue defect at the free edge of the surgical site.

12.6 Postoperative Care and Complications Almost all phonomicrosurgical procedures are followed by some period of voice rest. This period can range from as short as 2 days and extend to possibly 14 days, depending on the specific nature of the surgery, compliance of the patient, the surgeon’s philosophy, and experience. In addition to voice rest, the patient should be encouraged to stay well-­ hydrated, continue treatment for laryngopharyngeal reflux disease if on therapy prior to surgery, and maintain gastroesophageal reflux disease (GERD) behavior modification. At the end of the prescribed strict voice rest period, stroboscopy should be performed to evaluate the recovery and healing process of the vocal fold. If there is adequate epithelial coverage, then the patient can be transitioned to “light voice use,” which is usually defined as speaking using a breathy, “airy” type of voice (not a whisper) for 5–10 min per hour. Light voice use is often used for an additional 7–10  days after the period of strict voice rest. There is rarely an indication for antibiotics associated with phonomicrosurgery or long-term steroid use. Some surgeons may use immediate intravenous, intramuscular, or intralesional steroids perioperatively to minimize postoperative edema.

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It is advisable to involve a speech-language pathologist to assist the patient in transitioning from strict voice rest to light voice use to ensure that the patient is using the optimal postoperative voice technique to facilitate healing and prevent injury in this important time period. Complications from phonomicrosurgery include failure of the microflap to appropriately redrape and adhere to the vocal fold. When this occurs, epithelial ingrowth underneath the microflap occurs, and surgical excision of the microflap is mandated. This is a rare complication. Excessive edema and even necrosis can occur to a microflap; this typically occurs when the microflap is overly traumatized or injured during the surgical procedure. Often, when this occurs, the vocal fold will heal adequately on its own with appropriate time and care. Dental injuries after phonomicrosurgery should be repaired to the patients’ satisfaction in a prompt manner to minimize negative feelings of the patient toward the surgeon. Lingual nerve injuries such as numbness of the tongue and/or a change in taste sensation occur in approximately 10–20% of patients after phonomicrosurgery. These symptoms are usually transitory, and, thus, the patient should be informed that these postoperative changes usually resolve on their own within the first month after surgery. Additional complications related to phonomicrosurgery are discussed in Chapter 14—“Perioperative Care for Phonomicrosurgery” and Chapter 15—“Management and Prevention of Complications Related to Phonomicrosurgery”). Key Points • Phonomicrosurgery is an elective, precise surgical procedure aimed to improve vocal function based on the principles of vocal fold physiology. • Phonomicrosurgery utilizes small, delicate surgical instrumentation and is performed with maximum control via high-powered microlaryngoscopy for optimal results. • Conservative removal of a submucosal pathology with preservation of the overlying normal epithelium and superficial lamina propria allows healing by primary intention and optimal voice quality after phonomicrosurgery. • The microflap approach to submucosal pathology of the vocal folds is an essential component of most phonomicrosurgical procedures and is a challenging surgical task that requires patience, appropriate instrumentation, surgical skill, and experience.

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Bibliography Akbulut S, Gartner-Schmidt JL, Gillespie AI, Young VN, Smith LJ, Rosen CA.  Voice outcomes following treatment of benign midmembranous vocal fold lesions using a nomenclature paradigm. Laryngoscope. 2016;126(2):415–20. Andrea M, Dias O. Rigid and contact endoscopy in microlaryngeal surgery: technique and atlas of clinical cases. Philadelphia: Lippincott Williams & Wilkins; 1995. Bastian RW.  Vocal fold microsurgery in singers. J Voice. 1996;10:389–404. Bouchayer M, Cornut G.  Microsurgical treatment of benign vocal fold lesions: indications, technique, results. Folia Phoniatr. 1992;44:155–84. Courey MS, Stone RE, Gardner GM, Ossoff RH.  Endoscopic vocal fold microflap: a three year experience. Ann Otol Rhinol Laryngol. 1995;104:267–73. Courey MS, Garrett CG, Ossoff RH. Medial microflap for excision of benign vocal fold lesions. Laryngoscope. 1997;107:340–4. Domanski M, Lee P, Sadeghi N. Cost-effective dental protection during rigid endoscopy. Laryngoscope. 2011;121:2590–1. Ford CN. Advances and refinements in phonosurgery. Laryngoscope. 1999;109:1891–900. Hirano M.  Structure and vibratory behavior of the vocal fold. In: Sawashima M, Cooper F, editors. Dynamic aspects of speech production. Tokyo: University of Tokyo; 1977. p. 13–30. Rosen CA, Andrade Filho PA, Scheffel L, Buckmire RA. Oropharyngeal complications of suspension laryngoscopy: a prospective study. Laryngoscope. 2005;115:1681–4. Sataloff RT, Spiegel JR, Heuer RJ, Barody MM, Emerich KA, Hawkshaw MJ, Rosen DC.  Laryngeal mini-microflap: a new technique and reassessment of the microflap saga. J Voice. 1995;9:198–204. Shapshay SM, Healy GB. New microlaryngeal instruments for phonatory surgery and pediatric applications. Ann Otol Rhinol Laryngol. 1990;98:821–3. Thekdi AA, Rosen CA. Surgical treatment of benign vocal fold lesions. Curr Opin Otolaryngol Head Neck Surg. 2003;10:492–6. Zeitels SM, Vaughan CW. External counter-pressure and internal distension for optimal exposure of the anterior glottal commissure. Ann Otol Rhinol Laryngol. 1994;103:669–75. Zeitels SM, Hillman RE, Desloge R, Mauri M, Doyle PB. Phonomicrosurgery in singers and performing artists: treatment outcomes, management theories, and future directions. Ann Otol Rhinol Laryngol. 2002;190(Suppl):21–40.

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13.1

Fundamental and Related Chapters

Please see Chapter 12—“Principles of Phonomicrosurgery”, Chapter 13—“Ergonomics of Phonomicrosurgery”, Chapter 18—“Vocal Fold Polyp and Reactive Lesion: Phonomicrosurgery”, Chapter 19—“Vocal Fold Cyst and Vocal Fold Fibrous Mass”, Chapter 20—“Reinke’s Edema”, Chapter 21—“Vocal Fold Granuloma”, Chapter 22—“Vocal Fold Leukoplakia and Epithelial Dysplasia: Phonomicrosurgery”, Chapter 23—“Surgical Treatment of Recurrent Respiratory Papillomatosis of the Larynx”, Chapter 24—“Vascular Lesions of the Vocal Fold: Phonomicrosurgery”, Chapter 25—“Vocal Fold Scar and Sulcus Deformities of the Vocal Fold”, Chapter 26—“Endoscopic Management of Teflon Granuloma”, Chapter 27—“Endoscopic Excision of Saccular Cyst”, Chapter 28—“Anterior Glottic Web”, Chapter 29—“Buccal Mucosal Grafting in the Larynx”, Chapter 30— “Vocal Fold Augmentation: Phonomicrosurgery”, and Chapter 31—“Superficial Vocal Fold Injection”

for musculoskeletal injury and possibly limiting their surgical precision.

13.3

Background and Literature Review

L. J. Smith (*) Department of Otolaryngology, University of Pittsburgh Medical Center, Pittsburgh, PA, USA e-mail: [email protected]

There has been growing interest on ergonomics in otolaryngology, showing that a majority (68–72%) of otolaryngologists experience musculoskeletal symptoms (i.e., back pain, neck pain). Specific to microlaryngeal surgery, a national survey of otolaryngologists revealed that 83% of respondents reported having musculoskeletal symptoms during microlaryngeal surgery, usually of the neck, upper back, shoulder, and lower back. Furthermore, musculoskeletal symptoms can persist up to 48 h after surgery (19% and 28% for surgeries 30 min, respectively). Shoulder pain (anterior and posterior) was also improved during a simulated laryngeal microsurgical task when in a more ergonomically favorable position. The long-term effect of repetitive musculoskeletal injury from a lifetime of microlaryngeal surgery is unknown at this time. We will describe what we, as surgeons, can do to improve surgical ergonomics during microlaryngeal surgery, thus mitigating the musculoskeletal effects on the surgeon. The National Institute of Occupational Safety and Health has critically reviewed work-related musculoskeletal disorders. Microlaryngeal surgery is an inherently at-risk maneuver due to its static nature with fixed work postures at a ~400-mm microscopic focal length, limb extension, and potential for neck flexion greater than 15°. A more favorable ergonomic position during microlaryngeal surgery was determined using the Rapid Upper Limb Assessment (RULA) tool, which is a validated method of estimating the risk of musculoskeletal injury in an occupational setting. Regardless of surgeon height, several factors that remain consistent to achieve a more favorable ergonomic posture include:

C. A. Rosen UCSF Voice & Swallowing Center, Department of Otolaryngology-Head & Neck Surgery, University of California, San Francisco, San Francisco, CA, USA e-mail: [email protected]

• Neck flexion between 0 and 10° • Laryngoscope angle ~40° from the horizon • Arm support

13.2

Introduction

Microlaryngeal surgery is a foundation in the care of patients with laryngeal pathologies, ranging from vocal fold augmentation and delicate microflap lesion excision to laser treatments of benign and malignant laryngeal lesions. It requires manual dexterity with refined movements. Unfortunately, surgeons often neglect their own surgical ergonomics when performing these surgeries, thus putting themselves at risk

© Springer Nature Switzerland AG 2024 C. A. Rosen, C. B. Simpson, Operative Techniques in Laryngology, https://doi.org/10.1007/978-3-031-34354-4_13

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A proper neck angle was optimized with use of a chair with built-in arm supports. The neck angle was consistently >10° flexion when using a Mayo stand or no arm support at all. Moreover, the L5/S1 compression forces were nearly fourfold greater without an arm support. With an optimized surgical position, the musculoskeletal risk of microlaryngeal surgery, as measured by RULA, was reduced from “poor posture with increased risk, thus necessitating changes in the near future” to “a potential risk to injury from the posture, which should be investigated further and corrected if possible.” In ergonomic research, muscle fatigue is defined as an increase in electromyographic amplitude and a decrease in median frequency over time. When performing a simulated microsurgical task in a more “favorable” rather than an “unfavorable” ergonomic position, muscle fatigue is reduced. Increased muscle fatigue is believed to result in microbreaks. Microbreaks are unconscious or conscious restorative measures to relieve muscle fatigue. An increased frequency of microbreaks was identified while in “unfavorable” ergonomic positions.

13.4 “Optimal” Surgical Ergonomics for Phonomicrosurgery • • • • •

Laryngoscope angle ~40° off the horizon Neck—0–10° flexion, never extension Forearm support Shoulders relaxed Laryngoscope height at the level of the mid-abdomen of the surgeon • Foot support to hip angle ~90° • Take microbreaks • Vertical alignment of the head, neck, shoulders, and hips

There are four factors to consider for optimizing surgeon ergonomic positioning: patient position, microscope features, surgeon positioning, and surgeon support. All of these can be manipulated to accomplish a more favorable ergonomic position. This is the recommended order to build good ergonomic positioning for microlaryngeal surgery.

13.4.1 Laryngoscope Angle Each patient’s unique anatomy dictates the largest size and shape of laryngoscope that can be safely placed. For example, laryngeal exposure is more challenging when patients have an anteriorly displaced larynx, elongated upper teeth, a small oral cavity, an enlarged tongue, and/or large mandibular tori. In these situations, after the laryngoscope is properly positioned for laryngeal visualization, the laryngoscope angle from the horizon is often greater than the desired 40° (Fig. 13.1). Placing the bed in the

Fig. 13.1  Laryngoscope angle of ~40°. A proper laryngoscope angle is achieved by modulating the bed angle, usually at the Trendelenburg position. In edentulous patients, sometimes reverse Trendelenburg positioning is used. This patient was placed on a ramp to facilitate laryngeal exposure related to large body habitus. Once the laryngoscope was suspended, the bed was placed in the Trendelenburg position until the laryngoscope angle was about 40° from the horizon. This step becomes much easier when the suspension device is affixed to the bed and not to a Mayo stand

Trendelenburg position (head down) until the laryngoscope angle is ~40° is facilitated by attaching the laryngoscope device to the bed frame itself. If the suspension device is placed on a Mayo stand, then suspension needs to be released every time the bed is moved and then resuspended. Laryngoscope suspension on the patient’s chest is discouraged due to the risk of injury to the patient’s chest. In rare occasions, reverse Trendelenburg is needed. This sometimes occurs with edentulous patients. Regardless, once the laryngoscope and desired laryngeal exposure is obtained, the bed should be tilted to achieve a laryngoscope angle of ~40° from the horizon. This laryngoscope angle results in the most comfortable wrist position for the surgeon and in improved ergonomic surgeon positioning.

13.4.2 Surgeon Neck Angle A proper surgeon neck position is critical to reducing musculoskeletal injury. The neck should never be extended, as

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Fig. 13.2  Surgeon neck angle. By changing the bed height and the surgeon chair height, a neutral surgeon neck position is achieved. Neck extension (a) is “never” proper positioning. In this case, by lowering the

patient bed and raising the surgeon chair height, a neutral neck position is achieved (b)

poses a high risk for musculoskeletal injury (Fig.  13.2a). Surgeon neck flexion is optimal between 0 and 10°. After the proper laryngoscope angle is achieved, the next step is to bring the operating table “to the surgeon” by altering the bed height (usually lowering it). Surgical microscopes with articulated eyepieces can be switched to a more superior or inferior position, which is extremely helpful to realign the surgeon’s neck closer to the neutral position. The placement of articulated eyepieces tends to be in a more superior position for surgeons with longer torsos and in a more inferior position if the surgeon’s torso is shorter. However, sometimes the patient’s anatomy and resultant laryngoscope angle, and thus bed positioning, is a contributing factor. The surgeon chair height is also raised or lowered, again, to facilitate a proper surgeon neck angle. This is the most challenging, but important, consideration. With several factors to consider in order to optimize surgeon neck angle (bed height, surgeon chair height, articulated microscope eyepieces), the surgeon should incorporate each of these factors during surgeon positioning, with regard to neck positioning (Fig. 13.2b). The surgeon chair and patient bed heights will vary from one surgeon to another, based upon each surgeon’s anthropomorphic stature in relation to leg and torso lengths.

13.4.3 Arm Support Arm support is critical for stabilization during fine motor maneuvers and optimal surgeon musculoskeletal positioning. Arm support on the chair itself is essential, as it optimizes the surgeon’s shoulder flexion angle (Fig. 13.3). There are several types of surgical chairs with arm supports, often used by ophthalmologists and neurosurgeons. These specialty surgeon chairs allow for the arm supports to move up and down and swing in and out. Some combination of these should allow for comfortable arm support for the surgeon. Using a Mayo stand can increase the shoulder flexion angle, and, with that, the risk of musculoskeletal injury increases as determined by RULA. The optimal contact point of the forearm support is unknown, but it is reasonable to suggest this is at the surgeon’s discretion of comfort and may also be related to the microsurgical task to be completed. Regardless, wrist freedom of motion is advocated, in order to allow for unimpeded rotation of microsurgical instruments. Likewise, using the elbow as a fulcrum requires use of large muscles such as the biceps and triceps for stabilization. Using the forearm as the fulcrum, there should be less activation of those large muscle groups, which should result in greater precision of motion.

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Fig. 13.3  Shoulder position and arm support. Comfortable shoulder positioning is needed. Often, the shoulders are positioned too high, resulting in a “cramped” feeling in the shoulder–neck region (Fig 13.3a). With nonoptimal arm support, the fulcrum of the arm support is incor-

rect. In this case, by raising the surgeon’s chair, a neutral neck position can be achieved (Fig 13.3b). The arm support height was also lowered, resulting in better mid-forearm support, with free motion at the wrists

The surgeon’s supported forearms should be at the lowest, yet comfortable, level possible to minimize stress on the shoulder and neck. The shoulders should be relaxed and not elevated or depressed. A common mistake is to have the forearm support too high, which increases the strain on the shoulder musculature, resulting in increased musculoskeletal discomfort. The distance of the proximal laryngoscope aperture to the surgeon is dictated by the microscope’s focal distance for laryngeal visualization and the type of surgical microscope. With that in mind, surgeon’s shoulder flexion will vary based upon arm length. Surgeons with longer arms will have less shoulder flexion, whereas those with shorter arms will have greater shoulder flexion. This is one of the ergonomic factors that needs special attention, in order to identify the most comfortable ergonomic shoulder position for a particular surgeon for each unique patient. Each surgeon should strive for the least amount of shoulder flexion,

based upon the factors discussed above. Too much shoulder flexion should be avoided, as this increases musculoskeletal risk.

13.4.4 Laryngoscope Height/Chair Height The optimal placement of the proximal laryngoscope in relation to the surgeon’s body is in the upper abdominal region. This will result in the arm–forearm angle to be the recommended at ~100°. Elevation of the laryngoscope to the level of the surgeon’s shoulders will result in too much shoulder flexion. Rarely can the laryngoscope be “too low” once the abovelisted ergonomic factors are accomplished. In order to accomplish neutral (possible slight flexion) positioning of the wrists, both bed and surgeon chair heights are manipulated. When properly positioned, the surgeon’s hands will be around the “lap” and the upper arm will be close to the torso (Fig. 13.4).

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A proper spine position will result from optimal bed and chair placements. These alterations are dictated by laryngoscope angle, resultant bed tilting, and the surgeon’s torso height.

13.4.5 Foot Support The surgeon’s chair height should allow for foot support, slight knee flexion, and hip joint flexion (~95°–100° recommended). This creates an anterior pelvis tilt, which reduces compression forces at the L5/S1 joint (Fig. 13.5a, b). If the surgeon’s chair height results in the lack of a proper hip joint flexion and foot support, then placement of a “step” for each foot should be utilized.

13.4.6 Microbreaks

Fig. 13.4  Laryngoscopy height/chair height. Keeping the “working area” in the mid-chest to the upper abdomen, in relation to the surgeon, will result in favorable arm flexion and thus less risk for injury. A common mistake is to “work too high,” with the laryngoscope height at the upper chest/shoulder area. This leads to increased arm flexion and thus increased wrist flexion, usually with an increased laryngoscope angle. Neutral-to-slight wrist extension is the best, whereas extreme wrist flexion is painful. A proper “working area” height is accomplished by altering bed and chair heights. The lower position of the surgeon’s hands and the minimal extension of the upper arm from the torso should be noted

Surgical microbreaks are effective in reversing muscle fatigue. It is unknown whether this results in enhanced surgeon precision, but it likely leads to reduced musculoskeletal discomfort. The length of time and the frequency of restorative microbreaks are unknown. The conscious addition of “micropauses” has been advocated to prevent surgeon fatigue associated with prolonged surgery. Although laryngeal microsurgery is usually of a fairly short duration,