- Email: [email protected]
NEW PROCEDURES FOR PARALYTIC DYSPHONIA
VOICE DISORDERS AND I'HONOSURGERY I
0030-6665/00 $15.00
+ .OO
NEW PROCEDURES FOR PARALYTIC DYSPHONIA Adduction Arytenopexy, Goretex" Medialization Laryngoplasty, and Cricothyroid Subluxation Steven M. Zeitels, MD
Laryngoplastic phonosurgery has emerged as the dominant surgical intervention for paralytic dysphonia. Although medialization of the musculomembranousvocal fold by rearranging the laryngeal cartilage frame,~,~ the syswork was described by Payr12 in 1915,12I s ~ h i k i ~championed temic analysis and laryngoplastic treatment of paralytic dysphonia in the 1970s. He designed his medialization procedure of the musculomembranous vocal fold using a synthetic implant in 19745and shortly thereafter he reported the arytenoid adduction procedure6 to treat patients with large glottal gaps caused by a malpositioned arytenoid. Patients who require repositioning of the arytenoid typically have minimal or unfavorable synkinetic reinnervation of the intrinsic laryngeal musculature. Therefore, the arytenoid is antero-infero-laterally displaced, resulting in a flaccid, foreshortened vocal fold. Isshiki's classical arytenoid adduction procedure mimics contraction of the lateral cricoarytenoid muscle and achieves rotation of the arytenoid by means of a suture placed through its muscular process and directed anteriorly through the thyroid lamina. The agonist-antagonisticadductor function of the other intrinsic muscles (lateral thyroarytenoid, interary* W. L. Gore & Associates, Flagstaff, AZ From the Department of Otology and Laryngology, Harvard Medical School; and the Division of Laryngology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts OTOLARYNGOLOGICCLINICS OF NORTH AMERICA VOLUME 33 * NUMBER 4 AUGUST 2000
841
842
ZEITELS
tenoid, and posterior cricoarytenoid) is not simulated, however. Therefore, the adduction arytenopexy procedure was designed to model the synchronous function of the aforementioned muscu1ature.l8In this technique, the arytenoid is positioned on the medial aspect of the cricoid facet, simulating normal adduction of the arytenoid during phonation. Goretex is used as an implant and is placed lateral to the paraglottic muscles (the inner thyroid perichondrium) to avoid wide excursion of the glottal tissues during entrained oscillation. The denervated musculature of the paraglottic space is highly susceptible to the potential closing forces caused by Bernoulli’s effect. This fact is used to counterbalancethe loss in normal elastic-recoil closing forces resulting from the denervation. Placing the arytenoid in appropriate position posteriorly, before the placement of an implant, achieves most of the medialization necessary for the edge of the musculomembranousvocal f 0 l d . ~ ~ 3 Outcome data from patients who have undergone adduction arytenopexy and medialization laryngoplasty reveal that fairly normal conversational-level phonation was achieved.I8There are, however, remarkable limitations of maximal-range capabilities, especially in frequency variation and maximal phonation time. These limitations are thought to result from suboptimal viscoelastic tension in the denervated vocal fold soft tissues despite the improvements in three-dimensional repositioning of the vocal edge. The need to increase viscoelastic tension in the denervated vocal fold, and thereby improve aerodynamically efficient entrained oscillation, has catalyzed the development of the cricothyroid (CT) subluxation procedure.I6 SURGICAL TECHNIQUE
Unless contraindicated, patients are given 0.2 mg/kg of dexamethasone (Decadron) 1 hour before the procedure. This medication helps minimize intraoperative swelling, which can alter judgment regarding the implant size, and reduces postoperative airway swelling. A standard horizontal incision is made in a natural neck crease overlying the region of the cricothyroid space. Subplatysmal flaps are raised to expose the infrahyoid strap musculature. Gelpi retractors are placed to maintain the flaps. A transverse incision is made through the strap muscles to expose the thyroid lamina. A double-pronged skin hook is placed lateral to the edge of the thyroid lamina and rotated anteromedially to define the edge of the thyroid lamina and the inferior cornu of the thyroid cartilage. A needletipped electrocautery knife is used to separate the inferior constrictor from the thyroid lamina (Fig. 1). The inferior cornu is identified and isolated so that the cricothyroid joint can be separated with a Mayo scissors (Fig. 2). Separating the cricothyroid joint and the associated inferior constrictor muscle from the thyroid cartilage allows further anteromedial rotation of the thyroid lamina (Fig. 3). Blunt dissection is performed in a cephalad and slightly anterior direction from the cricothyroid facet along the cricoid cartilage until the superior rim of the cricoid is encountered (see Fig. 3).
NEW PROCEDURES FOR PARALYTIC DYSPHONIA
843
Figure 1. A and B,A needle-tipped electrocautery knife is used to separate the inferior constrictor from the thyroid lamina. (From Zeitels SM: Adduction arytenopexy with medialization laryngoplasty and cricothyroidsubluxation: A new approach to paralytic dysphonia. Operative Techniques in Otolaryngology-Head and Neck Surgery 10:9-16, 1999; with permission.)
In performing these maneuvers, the lateral aspect of the pyriform mucosa has been bluntly dissected from the inner aspect of the thyroid lamina, and the medial aspect of the pynform mucosa has been separated from the posterolateral aspect of the cricoid (see Fig. 3). Posterior superior dissection along the top of the cricoid separates the lateral cricoarytenoid muscle from the muscular process and ensures that the cricoarytenoid joint can be identified easily (Fig. 4). The dissection along the superior rim of the cricoid leads to the muscular process of the arytenoid. The lateral cricoarytenoid muscle is encountered and is severed from its attachment to the arytenoid. The posterior cricoarytenoid muscle is then separated from the muscular process of the arytenoid (see Fig. 4). The cricoarytenoid joint is opened widely with a Steven’s scissors, and the curved, glistening white surface of the cricoid facet is identified (Fig. 5). The posterior cricoarytenoid muscle is separated from the posterior plate of the cricoid so that the posterior aspect of the cricoarytenoid joint is well seen and so there is room to place a suture through this region (see Fig. 5). A 4-0 Prolene suture on a cutting needle is placed through the posterior plate of the cricoid just medial to the facet, and the needle is brought out through the medial aspect of the cricoarytenoid joint (Fig. 6). The needle is then passed through the body of the arytenoid, and through the inner
844
ZEITELS
Figure 2. The inferior cornu is identified and isolated so that the cricothyroid joint can be separated with Mayo scissors. (From Zeitels SM: Adduction arytenopexy with medialization laryngoplastyand cricothyroid subluxation:A new approach to paralytic dysphonia.Operative Techniques in Otolaryngology-Head and Neck Surgery 10:9-16, 1999; with permission.)
aspect of the cricoid. The needle is advanced under the cricoid facet and through the posterior plate of the cricoid, where a slipknot is placed (see Fig. 6). The arytenoid is positioned so that its body is subluxed medially, just off the facet, and so that it is rocked internally in the natural plane of the curved joint. Once the arytenoid is secured, the thyroid lamina is replaced into its natural anatomic position. The position of the arytenoid is visualized with a flexible fiberoptic laryngoscope to check its position during a number of phonatory tasks. If the arytenoid is well situated, the arytenoid suture is affixed permanently. The voice is typically improved but dysphonic until the medialization is completed.*8 Subsequently, an inferiorly based thyroid perichondrial flap is developed, and a standard window is made in the thyroid lamina lateral to the musculomembranous vocal fold, as described by Isshiki (Fig. 71.5 The inner perichondrium of the thyroid lamina is preserved at the perimeter of the window. A small implant is fashioned from a thin sheet of Goretex so that it can be layered lateral to the inner perichondrium of the thyroid lamina. The Goretex can be stabilized with a 4 0 Prolene suture. The thyroid lamina window is repositioned in its original site, and it is also stabilized in position either with a Prolene suture or with its external perichondrium (Fig. 8), which can be preserved.
NEW PROCEDURES FOR PARALYTIC DYSPHONIA
845
Figure 3. Separating the cricothyroidjoint and associating the inferior constrictor muscle from the thyroid cartilage allows for further anteromedial rotation of the thyroid lamina. Blunt dissection is performed in a cephalad and slightly anterior direction from the cricothyroidfacet alongthe cricoid cartilage until the superior rim of the cricoid is encountered. The lateralaspect of the pyriform mucosa is bluntly dissected from the inner aspect of the thyroid lamina and the medial aspect of the pyriform mucosa is separated from the posterolateralaspect of the cricoid. (From Zeitels SM: Adduction arytenopexy with medialization laryngoplasty and cricothyroid subluxation: A new approach to paralytic dysphonia. Operative Techniques in Otolaryngology-Head and Neck Surgery 10:9-16, 1999; with permission.)
Figure 4. The posterior cricoarytenoidmuscle is separated from the muscular process of the arytenoid. (From Zeitels SM: Adduction arytenopexy with medialization laryngoplasty and cricothyroid subluxation: A new approach to paralytic dysphonia. Operative Techniques in Otolaryngology-Head and Neck Surgery 10:9-16, 1999; with permission.)
846
ZEITELS
Figure 5. The posterior cricoarytenoid muscle is separated from the posterior plate of the cricoid so that the posterior aspect of the cricoarytenoidjoint is well seen and there is room to place a suture through this region. (FromZeitels SM: Adduction arytenopexy with medialization laryngoplasty and cricothyroid subluxation: A new approach to paralytic dysphonia. Operative Techniques in Otolaryngology-Head and Neck Surgery 10:9-16, 1999; with permission.)
Figure 6. A, A 4-0 Prolene suture on a cutting needle is placed through the posterior plate of the cricoid just medial to the facet and the needle is brought out through the medial aspect of the cricoarytenoidjoint. 6,The needle is passed through the body of the arytenoid and then through the inner aspect of the cricoid. C,The needle is advanced under the cricoidfacet and through the posterior plate of the cricoid where a slip knot is placed. (from Zeitels SM: Adduction arytenopexy with medialization laryngoplasty and cricothyroid subluxation: A new approach to paralytic dysphonia. Operative Techniques in Otolaryngology-Head and Neck Surgery 10:9-16, 1999; with permission.)
NEW PROCEDURES FOR PARALYTIC DYSPHONIA
847
Figure 7. If a thin sheet of Goretex is used, it is layered in position and is stabilized with a 4-0 Prolene suture. (FromZeitels SM: Adduction arytenopexy with medializationlaryngoplasty and cricothyroidsubluxation: A new approach to paralytic dysphonia. Operative Techniques in Otolaryngology-Head and Neck Surgery 10:9-16, 1999; with permission.)
Figure 8. The newly described cricothyroid subluxation is accomplished by placing a 2-0 Prolene suture around the inferior cornu of the thyroid lamina. It is then passed in a submucosal fashion underneath the cricoid anteriorly. (FromZeitelsSM: Adduction arytenopexywith medialization laryngoplasty and cricothyroid subluxation: A new approach to paralytic dysphonia. Operative Techniques in Otolaryngology-Head and Neck Surgery 10:9-16, 1999; with permission.)
848
ZEITELS
Once the adduction arytenopexy and medializationlaryngoplasty are completed, a cricothyroid subluxation is performed to enhance vocal quality further. The newly described cricothyroid subluxationis accomplished by placing a 2-0 Prolene suture around the inferior cornu of the thyroid lamina. The suture is then passed in a submucosal fashion underneath the cricoid anteriorly (see Fig. 8). The suture is pulled taut (Fig. 9), which increases the distance between the cricoid facet and the attachment of the anterior commissure ligament. This suture ultimately increases the tension and length of the musculomembranous vocal fold on the paralyzed side. The tension on this suture is adjusted by using a slipknot while the patient perfoms a number of phonatory tasks, including maximal-range tasks such as use of pulse-register (vocal fry) through a falsetto register and glissando sliding scales. This cricothyroid subluxation suture simulates cricothyroid muscle contraction for countertension on the thyroarytenoid muscle and for increasing length of the musculo-membranous vocal fold. Once this procedure is completed, the strap muscles are reattached with 3-0 polyglactin (Vicryl)suture in a running fashion. The wound is irrigated, and a Penrose drain is placed. The platysma is also approximated in a running fashion with polyglactin suture, and then the skin is closed with 4-0 nylon suture.
Figure 9. The suture is pulled taut, which increases the distance between the cricoid facet and the attachment of the anterior commissure ligament. (From Zeitels SM: Adduction arytenopexy with medialization laryngoplasty and cricothyroid subluxation: A new approach to paralytic dysphonia. Operative Techniquesin Otolaryngology-Head and Neck Surgery 10:916, 1999; with permission.)
NEW PROCEDURES FOR PARALYTIC DYSPHONIA
849
A pressure dressing is applied, and the drain is removed on the first postoperative morning. The patient has a liquid diet on the first postoperative morning and advances to a normal diet as tolerated. Fiberoptic laryngoscopy is performed before discharge to ensure that there is not an excessive amount of edema that would warrant further observation. Typically, patients can be discharged on the first postoperative day. DISCUSSION
The ideal procedure for treating aerodynamic glottal incompetence, and, in turn,paralytic dysphonia, should attempt to simulate the normal vocal fold position during phonation with regard to the following interdependent parameters? 1. Position of the musculo-membranousregion in the axial plane 2. Position of the arytenoid in the axial plane 3. Height of the vocal fold 4. Length of the vocal fold 5. Contour of the vocal fold edge in the musculomembranousregion 6. Contour of the vocal fold edge in the arytenoid region 7. Mass and viscoelasticity of the vocal fold (augmentation versus medialization)
Furthermore, the ideal procedure would be easy to perform, associated with few complications, reliable, reversible, and not threaten the airway.15 The adduction arytenopexy procedurela most closely models the synchronous agonist-antagonist function of the lateral cricoarytenoid, interarytenoid, lateral thyroarytenoid, and posterior cricoarytenoid muscles during phonatory adduction. The cricothyroid subluxation techniqueI6is the first phonosurgical procedure for paralytic dysphonia that is primarily designed to increase unilateral length and tension of the vocal fold by simulating cricothyroid muscle function. Goretex medialization' has a number of unique qualities, but like many previously reported techniques, it is a modification of Isshiki's conventional implant approach. Adduction Arytenopexy
Adduction arytenopexy18is a modification of Isshiki's arytenoid adduction procedure: which was developed approximately 20 years ago. Arytenoid adduction simulated only the lateral cricoarytenoid muscle, whereas adduction arytenopexy simulates the synchronous adductor contraction of all of the intrinsic musculature. This arytenopexy procedure results in a longer vocal fold, which is appropriately aligned in all three dimensions with a well-conformed medial edge of the glottal aperture. Unlike the classic arytenoid adduction, in which an anteriorly directed suture is used, adduction arytenopexy achieves a longer vocal fold by posteriorly displacing the arytenoid and
850
ZEITELS
maintaining its position with a posteriorly based suture. This clinical observation was confirmed in a cadaver study.1sIn the same study, adduction arytenopexy was shown to be more effective than the classic arytenoid adduction in closing interarytenoid gaps. Adduction arytenopexy does not result in excessive hyperrotation of the vocal process. During adduction arytenopexy, the body of the arytenoid is medialized to the limit of the medial cricoarytenoid joint capsule in a normal, gliding fashion along the cricoid facet. It is clear from the convex contour of the cricoid facet and the precisely accommodating concave contour of the arytenoid base that hyperrotation (simulating the lateral cricoarytenoid muscle) on an axial plane is not characteristic of normal arytenoid adduction. Furthermore, pathologic hyperrotation of the arytenoid and hyperfunction of the lateral cricoarytenoid is typically observed in patients who present with vocal fold granuloma^.'^ Both Koufman’s diagrammatic depiction of a typical arytenoid adductionsand cadaver studies by Neuman et all1 reveal an abnormally contoured medial arytenoid that results in an abnormal interarytenoid chink. In many patients, the clinical significance of this chink may be minimized by reflux-induced redundant interarytenoid and periarytenoid soft tissue. The adduction arytenopexy dissection method which expose^^^,'^ the cricoarytenoid joint was found to be simpler than other techniques. Also, using the anatomical configuration of the cricoid facet to select the ideal position of the arytenoid has not been reported previously. These factors allowed placement of the arytenoid in a more normal adduction position for effective glottal closure during laryngeal sound production. Despite ideal positioning of the arytenoid during the arytenopexy procedure, intraoperative observations revealed that optimal vocal quality required an accompanying medialization laryngoplasty. The medialization laryngoplasty is needed because of the flaccidity of the denervated glottis, which results in valvular incompetence. Atrophy and fibrosis impair the elastic-recoil closing forces in the denervated glottal tissues. Stroboscopic examination reveals an abnormally wide excursion of the vocal edge and a long open phase quotient during vibratory cycles. . A well-positioned arytenoid obviates the need for complex implant shapes that are required to close the posterior glottis from an anteriorly positioned thyroid lamina window. There are also a number of technical advantages to performing medialization laryngoplasty with adduction arytenopexy rather than with arytenoid adduction. Because there is not an anterior thyroid lamina suture, the implant is unencumbered by the adduction of the arytenoid. Furthermore, adduction arytenopexy is performed before medialization, so the implant can be sized more accurately with the structural positioning of the posterior glottis already established. Finally, complex implant shapes that violate the thyroid lamina inner perichondrium are unnecessary. Adduction arytenopexy, which positions the arytenoid for normal phonation, allows a simple, smaller implant to be placed lateral to the thyroid perichondrium, because posterior glottic tissues are already aligned. With arytenopexy, the primary goal of the implant is to prevent
NEW PROCEDURES FOR PARALYTIC DYSPHONIA
851
lateral excursion of the flaccid paraglottic tissue during oscillatory cycles rather than to medialize the vocal edge, which is primarily accomplished by the adduction arytenopexy. The technique for implant medialization becomes similar to that required for patients with easily corrected vocal muscle atrophy. Goretex Medialization
The use of Goretex as a medialization implant was introduced by Hoffman and McCullochl and has been employed by the author for 2 years. The primary advantages of Goretex are its ease of handling, placement, and adjustability. The position of the Goretex can even be adjusted extensively while the implant remains within the patient rather than removing it for alteration, as is necessary with silicone (Silastic).These factors enhance the speed in which the operation can be performed. Goretex is also well suited to restore aerodynamic glottal competence when there are complex anatomic deformities, such as those encountered with trauma and cancer resection. In the author’s experience, there have been minimal complications in more than 60 cases. Cricothyroid Subluxation
The cricothyroid subluxation procedureI6has further enhanced postoperative vocal quality, because it is an easily adjustable method of increasing and varying the tension and length of the paralyzed and denervated musculomembranousvocal fold. Cricothyroidsubluxation is unlike all prior operations, which were designed primarily to treat paralytic dysphonia by repositioning the vocal fold edge.2,5-8*18 Those procedures that alter the tension and length of the vocal fold were designed to modify pitch rather than to treat paralytic d y ~ p h o n i a . 3 ,The ~ , ~cricothyroid -~~ subluxation suture (see Figs. 8,9) (1)models cricothyroid muscle contraction, (2) produces countertension on the thyroarytenoid muscle, and (3) increases the length of the musculomembranous vocal fold. Cricothyroid subluxation is easy to perform, is free from complications, and improves the acoustical outcome of other laryngoplastic phonosurgical procedures. The modified biomechanical properties from cricothyroid subluxation resulted in improved vocal outcome in all patient@ and was most remarkable in maximal-range capabilities. Cricothyroid subluxation enhanced the postoperative voice of patients whether they require medialization laryngoplasty alone or with adduction arytenopexy. Adduction arytenopexy had been shown to result in improvements in a number of objective measures of vocal function18by simulating normal glottal closure and reproducing the synchronous adductor-contractile characteristics of all of the intrinsic muscles. Vocal outcome measures, however, revealed limitations in maximal-range tasks, especially in dynamic frequency range.I8 This finding probably resulted from persistent
852
ZEITELS
flaccidity of the denervated thyroarytenoid musculature. Both Isshiki's2r6 and Zeitels'*6adducting arytenoid techniques separate the cricothyroid joint to expose the cricoarytenoid joint. During a collaborative cadaver dissection, Sataloff observed that separation and destabilization of the ipsilateral cricothyroid joint impairs the function of the contralateral cricothyroid muscle (Robert Sataloff, personal communication, 1998).Based on a similar observation, other authors have exposed the cricoarytenoid joint during arytenoid adduction by removing a posterior window of the thyroid lamina and leaving the cricothyroid joint intact.l0 Clinical observations revealed that after the cricothyroid joint was opened, the inferior cornu of the thyroid lamina became retrodisplaced with relation to the cricoid. This displacement meant that the previously fixed vocal fold length was shortened, and the tension of the thyroarytenoid muscle was reduced. Essentially, there was a decrease in the normal distance between the cricoarytenoid joint and the insertion of the anterior commissure tendon into the thyroid lamina. Foreshortening of the paralyzed vocal fold, induced by separating the cricothyroid joint, probably led to compensatoryhyperfunctional foreshortening of the normal vocal fold. This hyperfunctional adaptation occurs to align the vocal processes, which is a prerequisite for normal entrained oscillation during phonation. The decreased phonatory length of both vocal folds and the decreased viscoelastic tension of the paralyzed vocal fold resulted in limitations in acoustical maximal-range capabilities. Even though the paralyzed vocal fold was surgically placed under higher tension than in its preoperative state, after cricothyroid subluxation alThis paradox is probmost all patients could reach a lower freq~ency.'~,'~ ably explained by the fact that the vocal fold lengthened by subluxation facilitates less contralateral vocal fold hyperfunction. The cricothyroid subluxation procedure was designed to rechfy mechanical impediments, which were partially precipitated by disruption of the cricothyroid joint during laryngoplastic phonosurgical correction of paralytic dysphonia. Cricothyroid subluxation also improved the vocal outcome of patients who, because of somewhat favorable synlunesis, did not require an arytenoid procedure. In both scenarios, the objective measurements show that cricothyroid subluxation improved the aerodynamic efficiency of the glottal valve with a commensurate enhancement of the maximal-range acoustical characteristics of the voice. Subjective perceptions revealed that most patients demonstrated a register transition between modal and falsetto, an observation not previously reported. The author and co-workers are currently developing measurement techniques to demonstrate this passaggio. SUMMARY
The postoperative vocal outcome from the combined use of adduction arytenopexy, Goretex medialization laryngoplasty, and cricothyroid subluxation is such that most patients will have a normal phonation time
NEW PROCEDURES FOR PARALYTIC DYSPHONIA
853
and more than two octaves of dynamic range with minimal acoustic perturbation.I6With the addition of the adduction arytenopexy and cricothyroid subluxation procedures to the armamentarium of the phonosurgeon, all parameters for static reconstruction of the paralyzed vocal fold have been addressed. These new procedures have all been performed for more than 2 years with reliable results and with minimal complications. Future developments should primarily address dynamic reconstruction (reinnervation and electrical pacing) of the intrinsic laryngeal musculature. References 1. Hoffman HH, McCulloch TM: Medialization laryngoplasty with expanded polytetraflu-
oroethylene: Surgical technique and preliminary results. Ann Otol Rhinol Laryngol 107427-432,1998 2. Isshiki N Phonosurgery:Theory and Practice. Tokyo, Springer-Verlag, 1989 3. Isshiki N Recent advances in phonosurgery. Folia Phoniatrica 32:119-154,1980 4. Isshiki N: Surgery to elevate vocal pitch. In Isshiki N: Phonosurgery:Theory and Practice. Tokyo, Springer-Verlag, 1989, pp 141-155 5. Isshiki N, Morita H, Okamura H, et al: Thyroplasty as a new phonosurgical technique. Acta Otolaryngol (Stockh)78:451-457, 1974 6. Isshiki N, Tanabe M, Sawada M: Arytenoid adduction for unilateral vocal cord paralysis. Archives of Otolaryngology 104:555-558, 1978 7. Koufman J A Laryngoplasty for vocal cord medialization: An alternative to Teflon. Laryngoscope 96726-731,1986 8. Koufman JA, Isaacson GL Laryngoplastic phonosurgery. Otolaryngol Clin North Am 241151-1 177,1991 9. Le Jeune FE, Guice CE, Samuels PM Early experiences with vocal ligament tightening. Ann Otol Rhinol Laryngol92475-477,1983 10. Miller FR, Bryant GL, Netterville JL: Arytenoid adduction in vocal fold paralysis. Operative Techniques in Otolaryngology-Head and Neck Surgery, 10:36-41,1999 11. Neuman TR, Hengesteg A, Lepage MS, et al: Three-dimensional motion of the arytenoid adduction procedure in cadaver larynges. Ann Otol Rhinol Laryngol103:265-270,1994 12. Payr E: Plastik am schildknorpel zur Behebung der Folgen einseitiger Stimmbandlahmung. Dtsch Med Wochenschr 43:1265-1270,1915 13. Tucker H M Anterior commissure laryngoplasty for adjustment of vocal fold tension. Ann Otol Rhinol Laryngol94547-549,1985 14. Zeitels SM: Adduction arytenopexy with medialization laryngoplasty and crico-thyroid subluxation: A new approach to paralytic dysphonia. Operative Techniques in Otolaryngology-Head and Neck Surgery 109-16,1999 15. Zeitels SM Phonosurgery. Compr Ther 22:222-230,1996 16. Zeitels SM, Hillman RE: Crico-thyroid subluxation for enhancing laryngoplasticphonosurgery. Ann Otol Rhinol Laryngol, 1081126-1131,1999 17. Zeitels SM, Hillman RE, Radu A: Salient characteristics of patients with posterior laryngeal granulomas and ulcerations. Presented at the Voice Symposium, Philadelphia,June, 1997 18. Zeitels SM, Hochman I, Hillman RE: Adduction arytenopexy:A new procedure for paralytic dysphonia and the implicationsfor medialization laryngoplasty. Ann Otol Rhinol Laryngol1071-24,1998 Address reprint requests to Steven M. Zeitels, MD Division of Laryngology MassachusettsEye and Ear Infirmary 243 Charles Street Boston, MA 02114
0030-6665/00 $15.00
+ .OO
NEW PROCEDURES FOR PARALYTIC DYSPHONIA Adduction Arytenopexy, Goretex" Medialization Laryngoplasty, and Cricothyroid Subluxation Steven M. Zeitels, MD
Laryngoplastic phonosurgery has emerged as the dominant surgical intervention for paralytic dysphonia. Although medialization of the musculomembranousvocal fold by rearranging the laryngeal cartilage frame,~,~ the syswork was described by Payr12 in 1915,12I s ~ h i k i ~championed temic analysis and laryngoplastic treatment of paralytic dysphonia in the 1970s. He designed his medialization procedure of the musculomembranous vocal fold using a synthetic implant in 19745and shortly thereafter he reported the arytenoid adduction procedure6 to treat patients with large glottal gaps caused by a malpositioned arytenoid. Patients who require repositioning of the arytenoid typically have minimal or unfavorable synkinetic reinnervation of the intrinsic laryngeal musculature. Therefore, the arytenoid is antero-infero-laterally displaced, resulting in a flaccid, foreshortened vocal fold. Isshiki's classical arytenoid adduction procedure mimics contraction of the lateral cricoarytenoid muscle and achieves rotation of the arytenoid by means of a suture placed through its muscular process and directed anteriorly through the thyroid lamina. The agonist-antagonisticadductor function of the other intrinsic muscles (lateral thyroarytenoid, interary* W. L. Gore & Associates, Flagstaff, AZ From the Department of Otology and Laryngology, Harvard Medical School; and the Division of Laryngology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts OTOLARYNGOLOGICCLINICS OF NORTH AMERICA VOLUME 33 * NUMBER 4 AUGUST 2000
841
842
ZEITELS
tenoid, and posterior cricoarytenoid) is not simulated, however. Therefore, the adduction arytenopexy procedure was designed to model the synchronous function of the aforementioned muscu1ature.l8In this technique, the arytenoid is positioned on the medial aspect of the cricoid facet, simulating normal adduction of the arytenoid during phonation. Goretex is used as an implant and is placed lateral to the paraglottic muscles (the inner thyroid perichondrium) to avoid wide excursion of the glottal tissues during entrained oscillation. The denervated musculature of the paraglottic space is highly susceptible to the potential closing forces caused by Bernoulli’s effect. This fact is used to counterbalancethe loss in normal elastic-recoil closing forces resulting from the denervation. Placing the arytenoid in appropriate position posteriorly, before the placement of an implant, achieves most of the medialization necessary for the edge of the musculomembranousvocal f 0 l d . ~ ~ 3 Outcome data from patients who have undergone adduction arytenopexy and medialization laryngoplasty reveal that fairly normal conversational-level phonation was achieved.I8There are, however, remarkable limitations of maximal-range capabilities, especially in frequency variation and maximal phonation time. These limitations are thought to result from suboptimal viscoelastic tension in the denervated vocal fold soft tissues despite the improvements in three-dimensional repositioning of the vocal edge. The need to increase viscoelastic tension in the denervated vocal fold, and thereby improve aerodynamically efficient entrained oscillation, has catalyzed the development of the cricothyroid (CT) subluxation procedure.I6 SURGICAL TECHNIQUE
Unless contraindicated, patients are given 0.2 mg/kg of dexamethasone (Decadron) 1 hour before the procedure. This medication helps minimize intraoperative swelling, which can alter judgment regarding the implant size, and reduces postoperative airway swelling. A standard horizontal incision is made in a natural neck crease overlying the region of the cricothyroid space. Subplatysmal flaps are raised to expose the infrahyoid strap musculature. Gelpi retractors are placed to maintain the flaps. A transverse incision is made through the strap muscles to expose the thyroid lamina. A double-pronged skin hook is placed lateral to the edge of the thyroid lamina and rotated anteromedially to define the edge of the thyroid lamina and the inferior cornu of the thyroid cartilage. A needletipped electrocautery knife is used to separate the inferior constrictor from the thyroid lamina (Fig. 1). The inferior cornu is identified and isolated so that the cricothyroid joint can be separated with a Mayo scissors (Fig. 2). Separating the cricothyroid joint and the associated inferior constrictor muscle from the thyroid cartilage allows further anteromedial rotation of the thyroid lamina (Fig. 3). Blunt dissection is performed in a cephalad and slightly anterior direction from the cricothyroid facet along the cricoid cartilage until the superior rim of the cricoid is encountered (see Fig. 3).
NEW PROCEDURES FOR PARALYTIC DYSPHONIA
843
Figure 1. A and B,A needle-tipped electrocautery knife is used to separate the inferior constrictor from the thyroid lamina. (From Zeitels SM: Adduction arytenopexy with medialization laryngoplasty and cricothyroidsubluxation: A new approach to paralytic dysphonia. Operative Techniques in Otolaryngology-Head and Neck Surgery 10:9-16, 1999; with permission.)
In performing these maneuvers, the lateral aspect of the pyriform mucosa has been bluntly dissected from the inner aspect of the thyroid lamina, and the medial aspect of the pynform mucosa has been separated from the posterolateral aspect of the cricoid (see Fig. 3). Posterior superior dissection along the top of the cricoid separates the lateral cricoarytenoid muscle from the muscular process and ensures that the cricoarytenoid joint can be identified easily (Fig. 4). The dissection along the superior rim of the cricoid leads to the muscular process of the arytenoid. The lateral cricoarytenoid muscle is encountered and is severed from its attachment to the arytenoid. The posterior cricoarytenoid muscle is then separated from the muscular process of the arytenoid (see Fig. 4). The cricoarytenoid joint is opened widely with a Steven’s scissors, and the curved, glistening white surface of the cricoid facet is identified (Fig. 5). The posterior cricoarytenoid muscle is separated from the posterior plate of the cricoid so that the posterior aspect of the cricoarytenoid joint is well seen and so there is room to place a suture through this region (see Fig. 5). A 4-0 Prolene suture on a cutting needle is placed through the posterior plate of the cricoid just medial to the facet, and the needle is brought out through the medial aspect of the cricoarytenoid joint (Fig. 6). The needle is then passed through the body of the arytenoid, and through the inner
844
ZEITELS
Figure 2. The inferior cornu is identified and isolated so that the cricothyroid joint can be separated with Mayo scissors. (From Zeitels SM: Adduction arytenopexy with medialization laryngoplastyand cricothyroid subluxation:A new approach to paralytic dysphonia.Operative Techniques in Otolaryngology-Head and Neck Surgery 10:9-16, 1999; with permission.)
aspect of the cricoid. The needle is advanced under the cricoid facet and through the posterior plate of the cricoid, where a slipknot is placed (see Fig. 6). The arytenoid is positioned so that its body is subluxed medially, just off the facet, and so that it is rocked internally in the natural plane of the curved joint. Once the arytenoid is secured, the thyroid lamina is replaced into its natural anatomic position. The position of the arytenoid is visualized with a flexible fiberoptic laryngoscope to check its position during a number of phonatory tasks. If the arytenoid is well situated, the arytenoid suture is affixed permanently. The voice is typically improved but dysphonic until the medialization is completed.*8 Subsequently, an inferiorly based thyroid perichondrial flap is developed, and a standard window is made in the thyroid lamina lateral to the musculomembranous vocal fold, as described by Isshiki (Fig. 71.5 The inner perichondrium of the thyroid lamina is preserved at the perimeter of the window. A small implant is fashioned from a thin sheet of Goretex so that it can be layered lateral to the inner perichondrium of the thyroid lamina. The Goretex can be stabilized with a 4 0 Prolene suture. The thyroid lamina window is repositioned in its original site, and it is also stabilized in position either with a Prolene suture or with its external perichondrium (Fig. 8), which can be preserved.
NEW PROCEDURES FOR PARALYTIC DYSPHONIA
845
Figure 3. Separating the cricothyroidjoint and associating the inferior constrictor muscle from the thyroid cartilage allows for further anteromedial rotation of the thyroid lamina. Blunt dissection is performed in a cephalad and slightly anterior direction from the cricothyroidfacet alongthe cricoid cartilage until the superior rim of the cricoid is encountered. The lateralaspect of the pyriform mucosa is bluntly dissected from the inner aspect of the thyroid lamina and the medial aspect of the pyriform mucosa is separated from the posterolateralaspect of the cricoid. (From Zeitels SM: Adduction arytenopexy with medialization laryngoplasty and cricothyroid subluxation: A new approach to paralytic dysphonia. Operative Techniques in Otolaryngology-Head and Neck Surgery 10:9-16, 1999; with permission.)
Figure 4. The posterior cricoarytenoidmuscle is separated from the muscular process of the arytenoid. (From Zeitels SM: Adduction arytenopexy with medialization laryngoplasty and cricothyroid subluxation: A new approach to paralytic dysphonia. Operative Techniques in Otolaryngology-Head and Neck Surgery 10:9-16, 1999; with permission.)
846
ZEITELS
Figure 5. The posterior cricoarytenoid muscle is separated from the posterior plate of the cricoid so that the posterior aspect of the cricoarytenoidjoint is well seen and there is room to place a suture through this region. (FromZeitels SM: Adduction arytenopexy with medialization laryngoplasty and cricothyroid subluxation: A new approach to paralytic dysphonia. Operative Techniques in Otolaryngology-Head and Neck Surgery 10:9-16, 1999; with permission.)
Figure 6. A, A 4-0 Prolene suture on a cutting needle is placed through the posterior plate of the cricoid just medial to the facet and the needle is brought out through the medial aspect of the cricoarytenoidjoint. 6,The needle is passed through the body of the arytenoid and then through the inner aspect of the cricoid. C,The needle is advanced under the cricoidfacet and through the posterior plate of the cricoid where a slip knot is placed. (from Zeitels SM: Adduction arytenopexy with medialization laryngoplasty and cricothyroid subluxation: A new approach to paralytic dysphonia. Operative Techniques in Otolaryngology-Head and Neck Surgery 10:9-16, 1999; with permission.)
NEW PROCEDURES FOR PARALYTIC DYSPHONIA
847
Figure 7. If a thin sheet of Goretex is used, it is layered in position and is stabilized with a 4-0 Prolene suture. (FromZeitels SM: Adduction arytenopexy with medializationlaryngoplasty and cricothyroidsubluxation: A new approach to paralytic dysphonia. Operative Techniques in Otolaryngology-Head and Neck Surgery 10:9-16, 1999; with permission.)
Figure 8. The newly described cricothyroid subluxation is accomplished by placing a 2-0 Prolene suture around the inferior cornu of the thyroid lamina. It is then passed in a submucosal fashion underneath the cricoid anteriorly. (FromZeitelsSM: Adduction arytenopexywith medialization laryngoplasty and cricothyroid subluxation: A new approach to paralytic dysphonia. Operative Techniques in Otolaryngology-Head and Neck Surgery 10:9-16, 1999; with permission.)
848
ZEITELS
Once the adduction arytenopexy and medializationlaryngoplasty are completed, a cricothyroid subluxation is performed to enhance vocal quality further. The newly described cricothyroid subluxationis accomplished by placing a 2-0 Prolene suture around the inferior cornu of the thyroid lamina. The suture is then passed in a submucosal fashion underneath the cricoid anteriorly (see Fig. 8). The suture is pulled taut (Fig. 9), which increases the distance between the cricoid facet and the attachment of the anterior commissure ligament. This suture ultimately increases the tension and length of the musculomembranous vocal fold on the paralyzed side. The tension on this suture is adjusted by using a slipknot while the patient perfoms a number of phonatory tasks, including maximal-range tasks such as use of pulse-register (vocal fry) through a falsetto register and glissando sliding scales. This cricothyroid subluxation suture simulates cricothyroid muscle contraction for countertension on the thyroarytenoid muscle and for increasing length of the musculo-membranous vocal fold. Once this procedure is completed, the strap muscles are reattached with 3-0 polyglactin (Vicryl)suture in a running fashion. The wound is irrigated, and a Penrose drain is placed. The platysma is also approximated in a running fashion with polyglactin suture, and then the skin is closed with 4-0 nylon suture.
Figure 9. The suture is pulled taut, which increases the distance between the cricoid facet and the attachment of the anterior commissure ligament. (From Zeitels SM: Adduction arytenopexy with medialization laryngoplasty and cricothyroid subluxation: A new approach to paralytic dysphonia. Operative Techniquesin Otolaryngology-Head and Neck Surgery 10:916, 1999; with permission.)
NEW PROCEDURES FOR PARALYTIC DYSPHONIA
849
A pressure dressing is applied, and the drain is removed on the first postoperative morning. The patient has a liquid diet on the first postoperative morning and advances to a normal diet as tolerated. Fiberoptic laryngoscopy is performed before discharge to ensure that there is not an excessive amount of edema that would warrant further observation. Typically, patients can be discharged on the first postoperative day. DISCUSSION
The ideal procedure for treating aerodynamic glottal incompetence, and, in turn,paralytic dysphonia, should attempt to simulate the normal vocal fold position during phonation with regard to the following interdependent parameters? 1. Position of the musculo-membranousregion in the axial plane 2. Position of the arytenoid in the axial plane 3. Height of the vocal fold 4. Length of the vocal fold 5. Contour of the vocal fold edge in the musculomembranousregion 6. Contour of the vocal fold edge in the arytenoid region 7. Mass and viscoelasticity of the vocal fold (augmentation versus medialization)
Furthermore, the ideal procedure would be easy to perform, associated with few complications, reliable, reversible, and not threaten the airway.15 The adduction arytenopexy procedurela most closely models the synchronous agonist-antagonist function of the lateral cricoarytenoid, interarytenoid, lateral thyroarytenoid, and posterior cricoarytenoid muscles during phonatory adduction. The cricothyroid subluxation techniqueI6is the first phonosurgical procedure for paralytic dysphonia that is primarily designed to increase unilateral length and tension of the vocal fold by simulating cricothyroid muscle function. Goretex medialization' has a number of unique qualities, but like many previously reported techniques, it is a modification of Isshiki's conventional implant approach. Adduction Arytenopexy
Adduction arytenopexy18is a modification of Isshiki's arytenoid adduction procedure: which was developed approximately 20 years ago. Arytenoid adduction simulated only the lateral cricoarytenoid muscle, whereas adduction arytenopexy simulates the synchronous adductor contraction of all of the intrinsic musculature. This arytenopexy procedure results in a longer vocal fold, which is appropriately aligned in all three dimensions with a well-conformed medial edge of the glottal aperture. Unlike the classic arytenoid adduction, in which an anteriorly directed suture is used, adduction arytenopexy achieves a longer vocal fold by posteriorly displacing the arytenoid and
850
ZEITELS
maintaining its position with a posteriorly based suture. This clinical observation was confirmed in a cadaver study.1sIn the same study, adduction arytenopexy was shown to be more effective than the classic arytenoid adduction in closing interarytenoid gaps. Adduction arytenopexy does not result in excessive hyperrotation of the vocal process. During adduction arytenopexy, the body of the arytenoid is medialized to the limit of the medial cricoarytenoid joint capsule in a normal, gliding fashion along the cricoid facet. It is clear from the convex contour of the cricoid facet and the precisely accommodating concave contour of the arytenoid base that hyperrotation (simulating the lateral cricoarytenoid muscle) on an axial plane is not characteristic of normal arytenoid adduction. Furthermore, pathologic hyperrotation of the arytenoid and hyperfunction of the lateral cricoarytenoid is typically observed in patients who present with vocal fold granuloma^.'^ Both Koufman’s diagrammatic depiction of a typical arytenoid adductionsand cadaver studies by Neuman et all1 reveal an abnormally contoured medial arytenoid that results in an abnormal interarytenoid chink. In many patients, the clinical significance of this chink may be minimized by reflux-induced redundant interarytenoid and periarytenoid soft tissue. The adduction arytenopexy dissection method which expose^^^,'^ the cricoarytenoid joint was found to be simpler than other techniques. Also, using the anatomical configuration of the cricoid facet to select the ideal position of the arytenoid has not been reported previously. These factors allowed placement of the arytenoid in a more normal adduction position for effective glottal closure during laryngeal sound production. Despite ideal positioning of the arytenoid during the arytenopexy procedure, intraoperative observations revealed that optimal vocal quality required an accompanying medialization laryngoplasty. The medialization laryngoplasty is needed because of the flaccidity of the denervated glottis, which results in valvular incompetence. Atrophy and fibrosis impair the elastic-recoil closing forces in the denervated glottal tissues. Stroboscopic examination reveals an abnormally wide excursion of the vocal edge and a long open phase quotient during vibratory cycles. . A well-positioned arytenoid obviates the need for complex implant shapes that are required to close the posterior glottis from an anteriorly positioned thyroid lamina window. There are also a number of technical advantages to performing medialization laryngoplasty with adduction arytenopexy rather than with arytenoid adduction. Because there is not an anterior thyroid lamina suture, the implant is unencumbered by the adduction of the arytenoid. Furthermore, adduction arytenopexy is performed before medialization, so the implant can be sized more accurately with the structural positioning of the posterior glottis already established. Finally, complex implant shapes that violate the thyroid lamina inner perichondrium are unnecessary. Adduction arytenopexy, which positions the arytenoid for normal phonation, allows a simple, smaller implant to be placed lateral to the thyroid perichondrium, because posterior glottic tissues are already aligned. With arytenopexy, the primary goal of the implant is to prevent
NEW PROCEDURES FOR PARALYTIC DYSPHONIA
851
lateral excursion of the flaccid paraglottic tissue during oscillatory cycles rather than to medialize the vocal edge, which is primarily accomplished by the adduction arytenopexy. The technique for implant medialization becomes similar to that required for patients with easily corrected vocal muscle atrophy. Goretex Medialization
The use of Goretex as a medialization implant was introduced by Hoffman and McCullochl and has been employed by the author for 2 years. The primary advantages of Goretex are its ease of handling, placement, and adjustability. The position of the Goretex can even be adjusted extensively while the implant remains within the patient rather than removing it for alteration, as is necessary with silicone (Silastic).These factors enhance the speed in which the operation can be performed. Goretex is also well suited to restore aerodynamic glottal competence when there are complex anatomic deformities, such as those encountered with trauma and cancer resection. In the author’s experience, there have been minimal complications in more than 60 cases. Cricothyroid Subluxation
The cricothyroid subluxation procedureI6has further enhanced postoperative vocal quality, because it is an easily adjustable method of increasing and varying the tension and length of the paralyzed and denervated musculomembranousvocal fold. Cricothyroidsubluxation is unlike all prior operations, which were designed primarily to treat paralytic dysphonia by repositioning the vocal fold edge.2,5-8*18 Those procedures that alter the tension and length of the vocal fold were designed to modify pitch rather than to treat paralytic d y ~ p h o n i a . 3 ,The ~ , ~cricothyroid -~~ subluxation suture (see Figs. 8,9) (1)models cricothyroid muscle contraction, (2) produces countertension on the thyroarytenoid muscle, and (3) increases the length of the musculomembranous vocal fold. Cricothyroid subluxation is easy to perform, is free from complications, and improves the acoustical outcome of other laryngoplastic phonosurgical procedures. The modified biomechanical properties from cricothyroid subluxation resulted in improved vocal outcome in all patient@ and was most remarkable in maximal-range capabilities. Cricothyroid subluxation enhanced the postoperative voice of patients whether they require medialization laryngoplasty alone or with adduction arytenopexy. Adduction arytenopexy had been shown to result in improvements in a number of objective measures of vocal function18by simulating normal glottal closure and reproducing the synchronous adductor-contractile characteristics of all of the intrinsic muscles. Vocal outcome measures, however, revealed limitations in maximal-range tasks, especially in dynamic frequency range.I8 This finding probably resulted from persistent
852
ZEITELS
flaccidity of the denervated thyroarytenoid musculature. Both Isshiki's2r6 and Zeitels'*6adducting arytenoid techniques separate the cricothyroid joint to expose the cricoarytenoid joint. During a collaborative cadaver dissection, Sataloff observed that separation and destabilization of the ipsilateral cricothyroid joint impairs the function of the contralateral cricothyroid muscle (Robert Sataloff, personal communication, 1998).Based on a similar observation, other authors have exposed the cricoarytenoid joint during arytenoid adduction by removing a posterior window of the thyroid lamina and leaving the cricothyroid joint intact.l0 Clinical observations revealed that after the cricothyroid joint was opened, the inferior cornu of the thyroid lamina became retrodisplaced with relation to the cricoid. This displacement meant that the previously fixed vocal fold length was shortened, and the tension of the thyroarytenoid muscle was reduced. Essentially, there was a decrease in the normal distance between the cricoarytenoid joint and the insertion of the anterior commissure tendon into the thyroid lamina. Foreshortening of the paralyzed vocal fold, induced by separating the cricothyroid joint, probably led to compensatoryhyperfunctional foreshortening of the normal vocal fold. This hyperfunctional adaptation occurs to align the vocal processes, which is a prerequisite for normal entrained oscillation during phonation. The decreased phonatory length of both vocal folds and the decreased viscoelastic tension of the paralyzed vocal fold resulted in limitations in acoustical maximal-range capabilities. Even though the paralyzed vocal fold was surgically placed under higher tension than in its preoperative state, after cricothyroid subluxation alThis paradox is probmost all patients could reach a lower freq~ency.'~,'~ ably explained by the fact that the vocal fold lengthened by subluxation facilitates less contralateral vocal fold hyperfunction. The cricothyroid subluxation procedure was designed to rechfy mechanical impediments, which were partially precipitated by disruption of the cricothyroid joint during laryngoplastic phonosurgical correction of paralytic dysphonia. Cricothyroid subluxation also improved the vocal outcome of patients who, because of somewhat favorable synlunesis, did not require an arytenoid procedure. In both scenarios, the objective measurements show that cricothyroid subluxation improved the aerodynamic efficiency of the glottal valve with a commensurate enhancement of the maximal-range acoustical characteristics of the voice. Subjective perceptions revealed that most patients demonstrated a register transition between modal and falsetto, an observation not previously reported. The author and co-workers are currently developing measurement techniques to demonstrate this passaggio. SUMMARY
The postoperative vocal outcome from the combined use of adduction arytenopexy, Goretex medialization laryngoplasty, and cricothyroid subluxation is such that most patients will have a normal phonation time
NEW PROCEDURES FOR PARALYTIC DYSPHONIA
853
and more than two octaves of dynamic range with minimal acoustic perturbation.I6With the addition of the adduction arytenopexy and cricothyroid subluxation procedures to the armamentarium of the phonosurgeon, all parameters for static reconstruction of the paralyzed vocal fold have been addressed. These new procedures have all been performed for more than 2 years with reliable results and with minimal complications. Future developments should primarily address dynamic reconstruction (reinnervation and electrical pacing) of the intrinsic laryngeal musculature. References 1. Hoffman HH, McCulloch TM: Medialization laryngoplasty with expanded polytetraflu-
oroethylene: Surgical technique and preliminary results. Ann Otol Rhinol Laryngol 107427-432,1998 2. Isshiki N Phonosurgery:Theory and Practice. Tokyo, Springer-Verlag, 1989 3. Isshiki N Recent advances in phonosurgery. Folia Phoniatrica 32:119-154,1980 4. Isshiki N: Surgery to elevate vocal pitch. In Isshiki N: Phonosurgery:Theory and Practice. Tokyo, Springer-Verlag, 1989, pp 141-155 5. Isshiki N, Morita H, Okamura H, et al: Thyroplasty as a new phonosurgical technique. Acta Otolaryngol (Stockh)78:451-457, 1974 6. Isshiki N, Tanabe M, Sawada M: Arytenoid adduction for unilateral vocal cord paralysis. Archives of Otolaryngology 104:555-558, 1978 7. Koufman J A Laryngoplasty for vocal cord medialization: An alternative to Teflon. Laryngoscope 96726-731,1986 8. Koufman JA, Isaacson GL Laryngoplastic phonosurgery. Otolaryngol Clin North Am 241151-1 177,1991 9. Le Jeune FE, Guice CE, Samuels PM Early experiences with vocal ligament tightening. Ann Otol Rhinol Laryngol92475-477,1983 10. Miller FR, Bryant GL, Netterville JL: Arytenoid adduction in vocal fold paralysis. Operative Techniques in Otolaryngology-Head and Neck Surgery, 10:36-41,1999 11. Neuman TR, Hengesteg A, Lepage MS, et al: Three-dimensional motion of the arytenoid adduction procedure in cadaver larynges. Ann Otol Rhinol Laryngol103:265-270,1994 12. Payr E: Plastik am schildknorpel zur Behebung der Folgen einseitiger Stimmbandlahmung. Dtsch Med Wochenschr 43:1265-1270,1915 13. Tucker H M Anterior commissure laryngoplasty for adjustment of vocal fold tension. Ann Otol Rhinol Laryngol94547-549,1985 14. Zeitels SM: Adduction arytenopexy with medialization laryngoplasty and crico-thyroid subluxation: A new approach to paralytic dysphonia. Operative Techniques in Otolaryngology-Head and Neck Surgery 109-16,1999 15. Zeitels SM Phonosurgery. Compr Ther 22:222-230,1996 16. Zeitels SM, Hillman RE: Crico-thyroid subluxation for enhancing laryngoplasticphonosurgery. Ann Otol Rhinol Laryngol, 1081126-1131,1999 17. Zeitels SM, Hillman RE, Radu A: Salient characteristics of patients with posterior laryngeal granulomas and ulcerations. Presented at the Voice Symposium, Philadelphia,June, 1997 18. Zeitels SM, Hochman I, Hillman RE: Adduction arytenopexy:A new procedure for paralytic dysphonia and the implicationsfor medialization laryngoplasty. Ann Otol Rhinol Laryngol1071-24,1998 Address reprint requests to Steven M. Zeitels, MD Division of Laryngology MassachusettsEye and Ear Infirmary 243 Charles Street Boston, MA 02114