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Reviewing and Refining Surgical Interventions for Glottic Insufficiency

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Reviewing and Refining Surgical Interventions for Glottic Insufficiency Reviewing and Refining Surgical Interventions for Glottic Insufficiency By Matthew R. Hoffman A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy (Communication Sciences and Disorders) at the UNIVERSITY OF WISCONSIN-MADISON 2013 Date of final oral examination: 4/25/13 The dissertation is approved by the following members of the Final Oral Committee: Jack J. Jiang, Professor, Surgery Timothy M. McCulloch, Associate Professor, Surgery Gary Weismer, Professor, Communication Sciences and Disorders Michelle R. Ciucci, Assistant Professor, Communication Sciences and Disorders Michael H. McDonald, Surgery Charles N. Ford, Professor Emeritus, Surgery i ACKNOWLEDGEMENTS Thank you to my committee members, Drs. Jack Jiang, Timothy McCulloch, Gary Weismer, Michelle Ciucci, Michael McDonald, and Charles Ford. They gave me their time and an opportunity when I was a young undergraduate student and had nothing to offer and challenged me to pursue new directions once I did. I am particularly grateful to: Dr. Jiang, for teaching me how to conduct research and think scientifically over the last eight years; Dr. McCulloch, for allowing me to help him pursue a new research interest and then helping me on any and all of mine; Dr. Weismer, for guiding me through the doctoral program; Dr. Ciucci, for the time she dedicated to helping me write this dissertation; Dr. McDonald, for revealing the wonders of the Eustachian tube and serving as my first clinical otolaryngology mentor; and Dr. Ford, for his constant willingness to work with and teach me, from our aerodynamic assessment of spasmodic dysphonia to our device for identifying the thyroplasty window position, and for allowing me to scrub in on an operation for the first time, a medialization thyroplasty. I would also like to thank: the past and present “Voice Lab All-Stars”, for their help on numerous projects and for making it a pleasure to go to work every day; my parents, Paul and Kathy Hoffman, for their constant support; and my fiancée, Marisa Kahler, for saying, “yes.” ii TABLE OF CONTENTS Chapter 1: Introduction ............................................................................................................................. 1 Introduction to and motivation for study .................................................................................................. 1 General structure of and innervation to the larynx.................................................................................... 2 Glottic insufficiency .................................................................................................................................. 7 Vocal fold paralysis ................................................................................................................................ 12 Quantitative analysis of voice production ............................................................................................... 21 Vocal fold vibration ................................................................................................................................ 25 Statement of the problem ........................................................................................................................ 28 Gaps in knowledge and studies to address them ..................................................................................... 29 References ............................................................................................................................................... 33 Chapter 2: Multi-parameter comparison of injection laryngoplasty, medialization laryngoplasty, and arytenoid adduction in an excised larynx model ............................................................................ 44 Chapter 3: Multi-parameter analysis of titanium vocal fold medializing implant in an excised larynx model .............................................................................................................................................. 65 Chapter 4: Optimal arytenoid adduction based on quantitative real-time voice analysis ................. 83 Chapter 5: Preliminary investigation of adjustable balloon implant for type I thyroplasty ........... 102 Chapter 6: Classification of glottic insufficiency and tension asymmetry using a multilayer perceptron ................................................................................................................................................ 119 Chapter 7: Initial investigation of anterior approach to arytenoid adduction in excised larynges . 139 Chapter 8: Excised larynx evaluation of wedge-shaped adjustable balloon implant for type I thyroplasty ............................................................................................................................................... 156 Chapter 9: Conclusion ............................................................................................................................ 172 Introduction to conclusion .................................................................................................................... 172 Summary of key findings ...................................................................................................................... 174 Review of work in context of current literature .................................................................................... 181 Clinical context ..................................................................................................................................... 188 Scientific context................................................................................................................................... 196 Limitations ............................................................................................................................................ 198 Areas for future study ........................................................................................................................... 201 Unanswered questions in otolaryngology ............................................................................................. 205 References ............................................................................................................................................. 216 Appendix .................................................................................................................................................. 227 Excised larynx bench apparatus ............................................................................................................ 227 Differences between canine and human larynx .................................................................................... 228 Mechanism of anterior arytenoid adduction ......................................................................................... 228 References ............................................................................................................................................. 229 iii ABSTRACT Glottic insufficiency is the primary anatomic etiology of dysphonia and a central abnormality of disorders such as vocal fold paralysis, presbylaryngis, and vocal fold scar. Treatment is primarily surgical and directed towards placing the affected fold in a midline position conducive to glottic closure and vocal fold vibration. Two open procedures offering permanent medialization include type I thyroplasty and arytenoid adduction. Thyroplasty uses an implant to medialize the affected vocal fold while arytenoid adduction uses a suture technique to accomplish the same goal. Though valuable and capable of providing a good outcome, both procedures are technically challenging and highly invasive. This series of seven studies used the excised larynx bench apparatus to perform a systematic, multiparametric assessment of current treatments and evaluate new devices which could simplify the procedures. Specifically, an adjustable silicone balloon implant which can be inserted via a minimally invasive minithyrotomy and a suture-wire complex which can be used to perform arytenoid adduction from a less invasive anterior approach were investigated. Experiments were performed using excised canine larynges and treatments were compared to both simulated unilateral vocal fold paralysis as well as normal conditions. Additionally, a range of aerodynamic, acoustic, and videokymographic parameters were employed and their ability to describe changes in phonation due to vocal fold medialization individually and collectively was determined. Vocal efficiency and perturbation parameters were demonstrated to be particularly effective at describing changes in laryngeal function as the arytenoid is rotated during arytenoid adduction. The wedge-shaped adjustable balloon implant provided effective medialization, closing the glottic gap and restoring normal vocal fold vibration. The suture-wire complex was effective for performing arytenoid adduction from an anterior aspect, thus eliminating the most challenging aspect of the procedure iv while not sacrificing outcome quality as judged by comparison to the traditional procedure. Further studies evaluating host response and long-term stability of these devices in living animals and human subjects are warranted. Adviser signature: __________________________ Jack Jiang, M.D., Ph.D. 1 CHAPTER 1 Introduction A. INTRODUCTION TO AND MOTIVATION FOR STUDY The larynx plays a crucial role in numerous physiological processes,
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