- Email: [email protected]
Revision laryngoplasty
@ @
o
~, , @ @
REVISION LARYNGOPLASTY JAMES A. KOUFMAN, MD, GREGORY N. POSTMA, MD
Medialization laryngoplasty has become a widely accepted surgical treatment for rehabilitation of unilateral vocal fold paralysis, paresis, and vocal fold bowing. Revision laryngoplasty is often challenging. The most common reasons for performing revision are improper procedure selection and implant-related problems such as malposition, undercorrection, and overcorrection. Understanding the reasons why revisions are necessary may help laryngoplastic phonosurgeons avoid some of the intrinsic pitfalls and technical problems and thus improve surgical outcomes.
Among 0tolaryngologists, medialization laryngoplasty (ML) for vocal fold paralysis, paresis, and bowing is currently popular for the surgical rehabilitation of patients with symptomatic glottal insufficiency,lm The techniques of ML vary from surgeon to surgeon; however, the majority of North American otolaryngologists still use customfashioned implants, carved from a firm silastic block. Other currently used implant materials are autologous cartilage, expanded polytetrafluoroethylene (Gore-Tex [W.L. Gore and Associates, Inc, Newark, DE]) 12 and hydroxylapatite. 13 One of the advantages of ML over other vocal fold augmentation techniques, such as polytef (Mentor Ophthalmics, Inc, Santa Barbara, CA) injection, is its relative reversibility.3,7,13,14Successful revision ML requires that the surgeon replace the preexisting implant with another one that more effectively alters the internal glottal contour. Thus, revision ML depends on the presence of relatively normal soft tissue adjacent to the original ML implant. Is ML with block silastic implant material really reversible? How and to what extent is the adjacent soft tissue altered? Ideall~ when an ML implant is removed, the surrounding tissue should be normal. In reality, it is altered but not to the extent that successful revision is thwarted. The authors estimate that they eventually revise approximately 8% of their own ML surgical patients. Their experience with revision ML (when a block silastic implant was initially used) indicates that a fibrous capsule of variable thickness and stiffness forms around the implant. In performing revisions, if a significantly larger or differentshaped implant is desired, it is usually necessary to medially incise this fibrous capsule. The capsule is generally fused with the inner thyroid cartilage perichondrium so that perichondrium is also incised. Once this is done, revision can proceed almost as if a previous ML had not been performed. It is difficult to revise patients who have had ML From the Center for Voice Disorders, Department of Otolaryngology, Wake Forest University School of Medicine, Winston-Salem, NC. Address reprint requests to James A. Koufman, MD, Center for Voice Disorders, Department of Otolaryngology,Wake Forest University School of Medicine, Medical Center Blvd, Winston-Salem, NC 27157-1034. Copyright © 1999 by W.B. Saunders Company 1043-1810/99/1001-0011 $10.00/0
procedures with hydroxylapatite implants because this material becomes so well incorporated into the surrounding tissues. 13Little is currently known about the reversibility of ML with Gore-Tex. Preformed silastic implants are commercially available, but they do not appear to offer any significant advantage. We do not recommend their use but instead perform ML with custom-carved block silastic. Fig I shows the configuration / shape of the silastic implant that is currently used for ML. 7,9 The most common reasons for performing revision ML are the following: (1) inappropriate patient a n d / o r procedure selection; (2) problems related to implant size, shape, a n d / o r position; and (3) failure to recognize an open posterior commissure, ie, the need for an arytenoid adduction procedure. These topics are the focus of this article.
INAPPROPRIATE PATIENT AND/OR PROCEDURE SELECTION
Unilateral or bilateral ML has been recommended for a variety of conditions; however, at present, the most well recognized and accepted indications are unilateral paralysis, 1-7 unilateral or bilateral paresis, 1°,11 and vocal fold bowing. 2,6,7,1°,n ML cannot close the posterior commissure when it is open no matter what shape, size, or type of implant material is used. 3,7,9 A common cause of a poor result after ML is that the posterior commissure remains open. The goal of revision surgery is usually its closure. The posterior flange of an ML implant, though it can abut and medialize the vocal process, can never close the posterior larynx (Fig 2A). Only the arytenoid adduction (AA) procedure 15 can effectively do this. 7,9,15,16 In addition, the AA procedure has another major advantage over ML alone, it reestablishes vocal fold length and height. A recently reported variation of the AA procedure, arytenopexy, seems to also achieve these goals. 16 When patients present for revision ML with an open posterior commissure, we recommend removal of the previously placed implant. This is because the posterior flange of the implant may be large enough to abut the vocal process and thus prevent optimal AA (Fig 2A). In other words, in performing combined M L / A A procedures, whether for revision or as a primary procedure, it is important that the posterior flange of the ML implant not
OPERATIVE TECHNIQUES IN OTOLARYNGOLOGY--HEAD AND NECK SURGERY, VOL 10, NO 1 (MAR), 1999: PP 61-65
61
•
///
,
FIGURE 1. Medialization laryngoplasty using a custom-carved silastic implant. The ML window is relatively low on the thyroid ala, and the shape of the implant conforms to the glottal gap to be closed. Note the deep scoring of the silastic implant so that the implant folds for ease of insertion.
interfere with the subsequent arytenoid rotation achieved by placement of the arytenoid sutures (Fig 2B). Unilateral vocal fold paralysis may be associated with a contralateral bowed vocal fold. This is commonly seen in older patients with preexistent presbylaryngis. Careful fiberoptic evaluation during soft voicing, before the onset
of compensatory supraglottic hyperfunction, is essential to determine contralateral bowing or atrophy. 1°,17 Some patients with contralateral bowing have shown a suboptimal voice after unilateral ML and AA. In such cases, subsequent ML for the other (bowed) side may yield dramatic vocal improvement• The authors perform an ipsilateral
FIGURE 2. Laryngoplasty in an older patient with a right vocal cord paralysis, with an open posterior commissure, and preexisting presbylaryngis. (A) Original procedure: the patient has had a right ML procedure, but the posterior commissure remains open and the contralateral vocal cord remains bowed. Not only is the postoperative voice result probably poor, but if the patient had swallowing and aspiration problems preoperatively, they are probably no better after this ML procedure. A revision is required. Note: Although the posterior flange of the ML implant medializes the right vocal process, it does not close the posterior commissure. In addition, an AA procedure might be compromised by the posterior flange of this implant, since optimal arytenoid rotation might be impeded and/or restricted. (B) Effective revision procedure: the patient has had a right ML with AA procedure and a contralateral ML. Note that the ML implant has a short posterior flange that does not impact the vocal process. 62
REVISION LARYNGOPLASTY
M L / A A and a contralateral ML at the same sitting for patients with unilateral paralysis with presbylaryngis. This bilateral procedure usually yields superb results. 1° Fig 2B shows the completed procedure for unilateral paralysis with presbylaryngis. IMPLANT-RELATED
PROBLEMS
The most common implant-related problems requiring revision ML are implant malposition (it is almost always too high), implant extrusion, overcorrection, and undercorrection. 6,9,14The most common of these errors is placement of the implant too high, so that it abuts the laryngeal ventricle a n d / o r the false vocal cord (Fig 3A). Unfortunately, when such malposition occurs, the postoperative result is usually poor, and subsequent implant extrusion (intrusion) is relatively common. The superior most portion of the vocal fold lies just under halfway between the thyroid notch and the bottom of the thyroid cartilage (Fig 4A). 9 However, it is important to recognize that many patients have a large inferior thyroid notch that may distort the perceived level of the vocal fold (Fig 4B). If the calculation is made in the midline and an inferior thyroid notch is ignored, then it is likely that the implant will be placed too high (See point "Wrong location" in Fig 4B). 9 The surgeon should palpate the
A
bottom of the thyroid cartilage away from the inferior thyroid notch, and then make the measurement as though the inferior thyroid notch did not exist. The w i n d o w / implant should also be kept nearly parallel to the vocal fold. Good exposure, so that the inferior edge of the thyroid ala can be palpated (lateral to an inferior notch) with a Freer elevator, helps ensure proper w i n d o w placement. When the implant w i n d o w has been placed too high, Whether or not extrusion has occurred, the surgeon can remove the implant and extend the window inferiorly. The inner perichondrium is reflected with an elevator, and an oscillating saw or angled Kerrison rongeur may be used to remove cartilage in a controlled manner. The implant then must be fashioned in such a way as to eccentrically produce medialization at the proper level (Fig 3B). The management of patients with an extruding implant is highly individualized. All patients are given broad spectrum antibiotics. If the implant is extruding externally; it is removed externally. If there is an internal communication with the endolarynx, the surgeon may modify/ enlarge the window, and a strap-muscle flap may be rotated into the window to maintain medialization. If there is no internal communication, a new, eccentric, customcarved implant may be inserted (Fig 3B). In any event, an implant should not be inserted in a contaminated field. If
/
B FIGURE 3. Targeted problem: the ML implant is too high. (A) Original procedure: the implant is too high (in the "ventricle) and only covered by a thin layer of soft tissue. This situation requires revision because the voice result is poor and eventual extrusion (intrusion) of this implant is likely. (13). Effective revision procedure: the window has bee n enlarged, the shape of the revision implant is eccentric, and the implant has been secured by sutures.
KOUFMANAND POSTMA
63
A
B
Wrong location
-Z--
Thyroid notch
.ocatior ~f uppel ~uperiot 'ocal foh
FIGURE 4. Proper ML window placement: how to estimate the level (superior edge) of the vocal fold (even when there is a large inferior thyroid notch). (A) No inferior thyroid notch: the superior edge of the vocal fold (Z) is midway between the thyroid notch (X) and the inferior border of the thyroid cartilage (Y). (B) When an inferior thyroid notch is present: the superior edge of the vocal fold is still at point Z, midway between the thyroid notch (X) and the imaginary inferior border of the thyroid cartilage (Y), as if there had been no inferior thyroid notch present. If the thyroid notch was improperly used as the inferior landmark, the Wrong point would have been selected as the external landmark for the vocal fold. This might result in improper window and/or implant placement, ie, it would be too high.
an implant is intruding into the larynx, it may be removed endoscopically; however, revision ML or injection augmentation should be performed at a later time. Overcorrection is a relatively infrequent problem with ML; however, when this occurs, it most commonly occurs anteriorly. Patients with anterior overcorrection often have a strained voice and a sensation of relative airway obstruction. In such cases, no mucosal waves are seen on stroboscopy. When mucosal waves are absent, revision ML may be indicated. Undercorrection of the glottal gap is a common problem. If the patient has persistent glottal incompetence caused by incomplete glottal closure (not because of a posterior gap), then revision ML or injection augmentation are indicated. If the estimated glottal gap seen on fiberoptic laryngoscopy is estimated at less than 1.0 ram, then injection augmentation with autologous fascia, fat, or collagen is an appropriate treatment; if the glottal gap is larger, then revision ML is performed. 1° On rare occasions, the cartilage window, when left in place in the patient, may migrate. This has occurred three times in the investigators' practice, and in each case the cartilage fragment could be removed endoscopically using the CO2 laser.
this uncommon complication occurs, it is usually near the anterior commissure. When a tear is present, foreignmaterial implantation should not be performed unless the defect is completely and securely closed. If the larynx is violated, we use intraoperative antibiotics and continue their use for 7 to 10 days after surgery. Implantation should definitely be avoided in this circumstance when the patient has had previous irradiation or when the implant would lie immediately adjacent to the tear. H o w soon after ML is endotracheal intubation performed? After ML, elective surgery using general anesthesia should be postponed for 6 months. Early on, laryngeal intubation with an endotracheal tube for general anesthesia is not recommended because of the possibility of dislodging the ML implant. (In 1 patient, an emergency procedure was performed 3 days after unilateral ML, and that patient developed a laryngeal hematoma and airway obstruction requiring a tracheotomy.) There is no evidence to ensure that the ML implant will be secure at 6 months; however, our experience with revision ML surgery at 6 months shows that a good fibrous capsule has already been formed. If intubation is necessary, it is recommended that the smallest possible diameter endotracheal tube be used. As an alternative, the laryngeal mask airway may be used.
SPECIAL
CONCLUSIONS
CONSIDERATIONS
When performing ML with AA, it is advisable to perform the ML first. The combination of ML / AA produces the best results in most patients with unilateral paralysis when the posterior commissure is open, and in our practice, a combined ML with AA is performed in approximately 2 out of 3 cases. What does one do when the piriform sinus is violated? When this occurs, it must be identified, closed, and the w o u n d drained. To ensure that this has not occurred, we have the patients whistle after filling the surgical site with saline and look for a stream of bubbles. After repair, we place a feeding tube and do not feed the patient for 2 days. What does one do when the larynx is violated? When 64
Before starting revision ML, careful fiberoptic examination as well as stroboscopy is critical to determine what errors occurred at the initial procedure or, potentially, what diagnosis has been overlooked. Knowledge of the common reasons for revision ML will allow all laryngoplastic surgeons to avoid such errors and, thus, decrease the need for revision surgery. REFERENCES
1. IsshikiN, Morita H, Okamura H: Thyroplastyas a new phonosurgical technique. ActaOtolaryngo178:451-457,1974 REVISION LARYNGOPLASTY
2. Isshiki N, Okamura H, Ishikawa T: Thyroplasty type I (lateral compression) for dysphonia due to vocal cord paralysis or atrophy. Acta Otolaryngol (Stockh) 80:465-473, 1975 3. Koufman JA: Laryngoplasty for vocal cord medialization:An alternative to Teflon. Laryngoscope 96:726-731, 1986 4. Wanamaker JR, Netterville JL, Ossoff RH: Phonosurgery. Silastic medializationfor unilateral vocal fold paralysis. Op Tech Otolaryngol Head Neck Surg 4:207-217, I993 5. Maves MD, McCabe BF, Gray S: Phonosurgery: Indications and pitfalls. Ann Otol Rhinol Laryngo198:577-580,1989 6. Koufman JA: Surgical correction of dysphonia due to bowing of the vocal cords. Ann Otol Rhinol Laryngo198:41-45,1989 7. Koufman JA, Isaacson G: Laryngoplastic phonosurgery. Otolaryngol Clin North Am 24:1151-1177,1991 8. Isshiki N, Shoji K, Kojima H, et ah Vocal fold atrophy and its surgical treatment. Ann Otol Rhinol Laryngo1105:182-188,1996 9. Koufman JA: Management of the paralyzed vocal cord, in Myers EN (ed): Operative Otolaryngology, chapter 43. Philadelphia, PA, Saunders, 1997, pp 380-395 10. Postma GN, Blalock PD, KoufmanJA: Bilateral medializationlaryngoplasty. Laryngoscope 108:1429-1434,1998
KOUFMANAND POSTMA
11. Koufman JA, Blalock PD, Postma GN: Vocal fold paresis. Presented at the annual meeting of the American Academy of Otolaryngology-Head and Neck Surger~ San Antonio, TX, September 15, 1998 12. McCulloch TM, Hoffman HT: Medialization laryngoplasty with expanded polytetrafluoroethylene. Ann Otol Rhinol Laryngo1107:427432, 1998 13. Flint PW, Corio RL, Cummings CW: Comparison of soft tissue response in rabbits following laryngeal implantation with hydroxylapatite, silicone rubber, and teflon. Ann Otol Rhinol Laryngol 106:399-407, 1997 14. Paniello RC, Dahm JD: Reversibility of medialization laryngoplasty. Ann Otol Rhinol Laryngo1106:902-908,1997 15. Isshiki N, Tanabe M, Sawada M: Arytenoid adduction for unilateral vocal cord paralysis. Arch Otolaryngo1104:555-558,1978 16. Zeitels SM, Hochman I, Hillman RE: Adduction arytenopexy: A new procedure for paralytic dysphonia with implications for implant medialization. Ann Otol Rhinol Laryngol 107:1-24, 1998 (suppl 173) 17. Koufman JA: Evaluation of laryngeal biomechanics by flberoptic laryngoscopy, in Rubin JS, Sataloff RT, Korovin GS, et al (eds): Diagnosis and Treatment of Voice Disorders, chapter 8. New York, NY, Igaku-Shoin, 1995, pp 122-136
65
o
~, , @ @
REVISION LARYNGOPLASTY JAMES A. KOUFMAN, MD, GREGORY N. POSTMA, MD
Medialization laryngoplasty has become a widely accepted surgical treatment for rehabilitation of unilateral vocal fold paralysis, paresis, and vocal fold bowing. Revision laryngoplasty is often challenging. The most common reasons for performing revision are improper procedure selection and implant-related problems such as malposition, undercorrection, and overcorrection. Understanding the reasons why revisions are necessary may help laryngoplastic phonosurgeons avoid some of the intrinsic pitfalls and technical problems and thus improve surgical outcomes.
Among 0tolaryngologists, medialization laryngoplasty (ML) for vocal fold paralysis, paresis, and bowing is currently popular for the surgical rehabilitation of patients with symptomatic glottal insufficiency,lm The techniques of ML vary from surgeon to surgeon; however, the majority of North American otolaryngologists still use customfashioned implants, carved from a firm silastic block. Other currently used implant materials are autologous cartilage, expanded polytetrafluoroethylene (Gore-Tex [W.L. Gore and Associates, Inc, Newark, DE]) 12 and hydroxylapatite. 13 One of the advantages of ML over other vocal fold augmentation techniques, such as polytef (Mentor Ophthalmics, Inc, Santa Barbara, CA) injection, is its relative reversibility.3,7,13,14Successful revision ML requires that the surgeon replace the preexisting implant with another one that more effectively alters the internal glottal contour. Thus, revision ML depends on the presence of relatively normal soft tissue adjacent to the original ML implant. Is ML with block silastic implant material really reversible? How and to what extent is the adjacent soft tissue altered? Ideall~ when an ML implant is removed, the surrounding tissue should be normal. In reality, it is altered but not to the extent that successful revision is thwarted. The authors estimate that they eventually revise approximately 8% of their own ML surgical patients. Their experience with revision ML (when a block silastic implant was initially used) indicates that a fibrous capsule of variable thickness and stiffness forms around the implant. In performing revisions, if a significantly larger or differentshaped implant is desired, it is usually necessary to medially incise this fibrous capsule. The capsule is generally fused with the inner thyroid cartilage perichondrium so that perichondrium is also incised. Once this is done, revision can proceed almost as if a previous ML had not been performed. It is difficult to revise patients who have had ML From the Center for Voice Disorders, Department of Otolaryngology, Wake Forest University School of Medicine, Winston-Salem, NC. Address reprint requests to James A. Koufman, MD, Center for Voice Disorders, Department of Otolaryngology,Wake Forest University School of Medicine, Medical Center Blvd, Winston-Salem, NC 27157-1034. Copyright © 1999 by W.B. Saunders Company 1043-1810/99/1001-0011 $10.00/0
procedures with hydroxylapatite implants because this material becomes so well incorporated into the surrounding tissues. 13Little is currently known about the reversibility of ML with Gore-Tex. Preformed silastic implants are commercially available, but they do not appear to offer any significant advantage. We do not recommend their use but instead perform ML with custom-carved block silastic. Fig I shows the configuration / shape of the silastic implant that is currently used for ML. 7,9 The most common reasons for performing revision ML are the following: (1) inappropriate patient a n d / o r procedure selection; (2) problems related to implant size, shape, a n d / o r position; and (3) failure to recognize an open posterior commissure, ie, the need for an arytenoid adduction procedure. These topics are the focus of this article.
INAPPROPRIATE PATIENT AND/OR PROCEDURE SELECTION
Unilateral or bilateral ML has been recommended for a variety of conditions; however, at present, the most well recognized and accepted indications are unilateral paralysis, 1-7 unilateral or bilateral paresis, 1°,11 and vocal fold bowing. 2,6,7,1°,n ML cannot close the posterior commissure when it is open no matter what shape, size, or type of implant material is used. 3,7,9 A common cause of a poor result after ML is that the posterior commissure remains open. The goal of revision surgery is usually its closure. The posterior flange of an ML implant, though it can abut and medialize the vocal process, can never close the posterior larynx (Fig 2A). Only the arytenoid adduction (AA) procedure 15 can effectively do this. 7,9,15,16 In addition, the AA procedure has another major advantage over ML alone, it reestablishes vocal fold length and height. A recently reported variation of the AA procedure, arytenopexy, seems to also achieve these goals. 16 When patients present for revision ML with an open posterior commissure, we recommend removal of the previously placed implant. This is because the posterior flange of the implant may be large enough to abut the vocal process and thus prevent optimal AA (Fig 2A). In other words, in performing combined M L / A A procedures, whether for revision or as a primary procedure, it is important that the posterior flange of the ML implant not
OPERATIVE TECHNIQUES IN OTOLARYNGOLOGY--HEAD AND NECK SURGERY, VOL 10, NO 1 (MAR), 1999: PP 61-65
61
•
///
,
FIGURE 1. Medialization laryngoplasty using a custom-carved silastic implant. The ML window is relatively low on the thyroid ala, and the shape of the implant conforms to the glottal gap to be closed. Note the deep scoring of the silastic implant so that the implant folds for ease of insertion.
interfere with the subsequent arytenoid rotation achieved by placement of the arytenoid sutures (Fig 2B). Unilateral vocal fold paralysis may be associated with a contralateral bowed vocal fold. This is commonly seen in older patients with preexistent presbylaryngis. Careful fiberoptic evaluation during soft voicing, before the onset
of compensatory supraglottic hyperfunction, is essential to determine contralateral bowing or atrophy. 1°,17 Some patients with contralateral bowing have shown a suboptimal voice after unilateral ML and AA. In such cases, subsequent ML for the other (bowed) side may yield dramatic vocal improvement• The authors perform an ipsilateral
FIGURE 2. Laryngoplasty in an older patient with a right vocal cord paralysis, with an open posterior commissure, and preexisting presbylaryngis. (A) Original procedure: the patient has had a right ML procedure, but the posterior commissure remains open and the contralateral vocal cord remains bowed. Not only is the postoperative voice result probably poor, but if the patient had swallowing and aspiration problems preoperatively, they are probably no better after this ML procedure. A revision is required. Note: Although the posterior flange of the ML implant medializes the right vocal process, it does not close the posterior commissure. In addition, an AA procedure might be compromised by the posterior flange of this implant, since optimal arytenoid rotation might be impeded and/or restricted. (B) Effective revision procedure: the patient has had a right ML with AA procedure and a contralateral ML. Note that the ML implant has a short posterior flange that does not impact the vocal process. 62
REVISION LARYNGOPLASTY
M L / A A and a contralateral ML at the same sitting for patients with unilateral paralysis with presbylaryngis. This bilateral procedure usually yields superb results. 1° Fig 2B shows the completed procedure for unilateral paralysis with presbylaryngis. IMPLANT-RELATED
PROBLEMS
The most common implant-related problems requiring revision ML are implant malposition (it is almost always too high), implant extrusion, overcorrection, and undercorrection. 6,9,14The most common of these errors is placement of the implant too high, so that it abuts the laryngeal ventricle a n d / o r the false vocal cord (Fig 3A). Unfortunately, when such malposition occurs, the postoperative result is usually poor, and subsequent implant extrusion (intrusion) is relatively common. The superior most portion of the vocal fold lies just under halfway between the thyroid notch and the bottom of the thyroid cartilage (Fig 4A). 9 However, it is important to recognize that many patients have a large inferior thyroid notch that may distort the perceived level of the vocal fold (Fig 4B). If the calculation is made in the midline and an inferior thyroid notch is ignored, then it is likely that the implant will be placed too high (See point "Wrong location" in Fig 4B). 9 The surgeon should palpate the
A
bottom of the thyroid cartilage away from the inferior thyroid notch, and then make the measurement as though the inferior thyroid notch did not exist. The w i n d o w / implant should also be kept nearly parallel to the vocal fold. Good exposure, so that the inferior edge of the thyroid ala can be palpated (lateral to an inferior notch) with a Freer elevator, helps ensure proper w i n d o w placement. When the implant w i n d o w has been placed too high, Whether or not extrusion has occurred, the surgeon can remove the implant and extend the window inferiorly. The inner perichondrium is reflected with an elevator, and an oscillating saw or angled Kerrison rongeur may be used to remove cartilage in a controlled manner. The implant then must be fashioned in such a way as to eccentrically produce medialization at the proper level (Fig 3B). The management of patients with an extruding implant is highly individualized. All patients are given broad spectrum antibiotics. If the implant is extruding externally; it is removed externally. If there is an internal communication with the endolarynx, the surgeon may modify/ enlarge the window, and a strap-muscle flap may be rotated into the window to maintain medialization. If there is no internal communication, a new, eccentric, customcarved implant may be inserted (Fig 3B). In any event, an implant should not be inserted in a contaminated field. If
/
B FIGURE 3. Targeted problem: the ML implant is too high. (A) Original procedure: the implant is too high (in the "ventricle) and only covered by a thin layer of soft tissue. This situation requires revision because the voice result is poor and eventual extrusion (intrusion) of this implant is likely. (13). Effective revision procedure: the window has bee n enlarged, the shape of the revision implant is eccentric, and the implant has been secured by sutures.
KOUFMANAND POSTMA
63
A
B
Wrong location
-Z--
Thyroid notch
.ocatior ~f uppel ~uperiot 'ocal foh
FIGURE 4. Proper ML window placement: how to estimate the level (superior edge) of the vocal fold (even when there is a large inferior thyroid notch). (A) No inferior thyroid notch: the superior edge of the vocal fold (Z) is midway between the thyroid notch (X) and the inferior border of the thyroid cartilage (Y). (B) When an inferior thyroid notch is present: the superior edge of the vocal fold is still at point Z, midway between the thyroid notch (X) and the imaginary inferior border of the thyroid cartilage (Y), as if there had been no inferior thyroid notch present. If the thyroid notch was improperly used as the inferior landmark, the Wrong point would have been selected as the external landmark for the vocal fold. This might result in improper window and/or implant placement, ie, it would be too high.
an implant is intruding into the larynx, it may be removed endoscopically; however, revision ML or injection augmentation should be performed at a later time. Overcorrection is a relatively infrequent problem with ML; however, when this occurs, it most commonly occurs anteriorly. Patients with anterior overcorrection often have a strained voice and a sensation of relative airway obstruction. In such cases, no mucosal waves are seen on stroboscopy. When mucosal waves are absent, revision ML may be indicated. Undercorrection of the glottal gap is a common problem. If the patient has persistent glottal incompetence caused by incomplete glottal closure (not because of a posterior gap), then revision ML or injection augmentation are indicated. If the estimated glottal gap seen on fiberoptic laryngoscopy is estimated at less than 1.0 ram, then injection augmentation with autologous fascia, fat, or collagen is an appropriate treatment; if the glottal gap is larger, then revision ML is performed. 1° On rare occasions, the cartilage window, when left in place in the patient, may migrate. This has occurred three times in the investigators' practice, and in each case the cartilage fragment could be removed endoscopically using the CO2 laser.
this uncommon complication occurs, it is usually near the anterior commissure. When a tear is present, foreignmaterial implantation should not be performed unless the defect is completely and securely closed. If the larynx is violated, we use intraoperative antibiotics and continue their use for 7 to 10 days after surgery. Implantation should definitely be avoided in this circumstance when the patient has had previous irradiation or when the implant would lie immediately adjacent to the tear. H o w soon after ML is endotracheal intubation performed? After ML, elective surgery using general anesthesia should be postponed for 6 months. Early on, laryngeal intubation with an endotracheal tube for general anesthesia is not recommended because of the possibility of dislodging the ML implant. (In 1 patient, an emergency procedure was performed 3 days after unilateral ML, and that patient developed a laryngeal hematoma and airway obstruction requiring a tracheotomy.) There is no evidence to ensure that the ML implant will be secure at 6 months; however, our experience with revision ML surgery at 6 months shows that a good fibrous capsule has already been formed. If intubation is necessary, it is recommended that the smallest possible diameter endotracheal tube be used. As an alternative, the laryngeal mask airway may be used.
SPECIAL
CONCLUSIONS
CONSIDERATIONS
When performing ML with AA, it is advisable to perform the ML first. The combination of ML / AA produces the best results in most patients with unilateral paralysis when the posterior commissure is open, and in our practice, a combined ML with AA is performed in approximately 2 out of 3 cases. What does one do when the piriform sinus is violated? When this occurs, it must be identified, closed, and the w o u n d drained. To ensure that this has not occurred, we have the patients whistle after filling the surgical site with saline and look for a stream of bubbles. After repair, we place a feeding tube and do not feed the patient for 2 days. What does one do when the larynx is violated? When 64
Before starting revision ML, careful fiberoptic examination as well as stroboscopy is critical to determine what errors occurred at the initial procedure or, potentially, what diagnosis has been overlooked. Knowledge of the common reasons for revision ML will allow all laryngoplastic surgeons to avoid such errors and, thus, decrease the need for revision surgery. REFERENCES
1. IsshikiN, Morita H, Okamura H: Thyroplastyas a new phonosurgical technique. ActaOtolaryngo178:451-457,1974 REVISION LARYNGOPLASTY
2. Isshiki N, Okamura H, Ishikawa T: Thyroplasty type I (lateral compression) for dysphonia due to vocal cord paralysis or atrophy. Acta Otolaryngol (Stockh) 80:465-473, 1975 3. Koufman JA: Laryngoplasty for vocal cord medialization:An alternative to Teflon. Laryngoscope 96:726-731, 1986 4. Wanamaker JR, Netterville JL, Ossoff RH: Phonosurgery. Silastic medializationfor unilateral vocal fold paralysis. Op Tech Otolaryngol Head Neck Surg 4:207-217, I993 5. Maves MD, McCabe BF, Gray S: Phonosurgery: Indications and pitfalls. Ann Otol Rhinol Laryngo198:577-580,1989 6. Koufman JA: Surgical correction of dysphonia due to bowing of the vocal cords. Ann Otol Rhinol Laryngo198:41-45,1989 7. Koufman JA, Isaacson G: Laryngoplastic phonosurgery. Otolaryngol Clin North Am 24:1151-1177,1991 8. Isshiki N, Shoji K, Kojima H, et ah Vocal fold atrophy and its surgical treatment. Ann Otol Rhinol Laryngo1105:182-188,1996 9. Koufman JA: Management of the paralyzed vocal cord, in Myers EN (ed): Operative Otolaryngology, chapter 43. Philadelphia, PA, Saunders, 1997, pp 380-395 10. Postma GN, Blalock PD, KoufmanJA: Bilateral medializationlaryngoplasty. Laryngoscope 108:1429-1434,1998
KOUFMANAND POSTMA
11. Koufman JA, Blalock PD, Postma GN: Vocal fold paresis. Presented at the annual meeting of the American Academy of Otolaryngology-Head and Neck Surger~ San Antonio, TX, September 15, 1998 12. McCulloch TM, Hoffman HT: Medialization laryngoplasty with expanded polytetrafluoroethylene. Ann Otol Rhinol Laryngo1107:427432, 1998 13. Flint PW, Corio RL, Cummings CW: Comparison of soft tissue response in rabbits following laryngeal implantation with hydroxylapatite, silicone rubber, and teflon. Ann Otol Rhinol Laryngol 106:399-407, 1997 14. Paniello RC, Dahm JD: Reversibility of medialization laryngoplasty. Ann Otol Rhinol Laryngo1106:902-908,1997 15. Isshiki N, Tanabe M, Sawada M: Arytenoid adduction for unilateral vocal cord paralysis. Arch Otolaryngo1104:555-558,1978 16. Zeitels SM, Hochman I, Hillman RE: Adduction arytenopexy: A new procedure for paralytic dysphonia with implications for implant medialization. Ann Otol Rhinol Laryngol 107:1-24, 1998 (suppl 173) 17. Koufman JA: Evaluation of laryngeal biomechanics by flberoptic laryngoscopy, in Rubin JS, Sataloff RT, Korovin GS, et al (eds): Diagnosis and Treatment of Voice Disorders, chapter 8. New York, NY, Igaku-Shoin, 1995, pp 122-136
65