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Medialization laryngoplasty with gore-tex
MEDIALIZATION LARYNGOPLASTY WITH GORE-TEX HENRY T. HOFFMAN, MD, TIMOTHY M. McCULLOCH, MD
Many techniques have been described to surgically treat symptomatic unilateral laryngeal paralysis through medialization laryngoplasty. A simplified approach that has consistently resulted in good vocal results is presented.
Although there is still no critical comparative analysis to define the best surgical approach to treating laryngeal paralysis, the best long-term phonatory results come from medialization laryngoplasty, often coupled with arytenoid adduction. Arytenoid adduction, when performed in isolation, does not consistently provide adequate glottic closure. It is best suited to position the vocal process in the phonatory position, but it does not always result in adequate medial positioning of the membranous vocal cord. A significant portion of the patients treated with arytenoid adduction alone have subsequently needed further treatment of the anterior glottis with either a fat injection or medialization laryngoplasty. As a result, most of the patients now treated with arytenoid adduction receive a concomitant medialization laryngoplasty. Those patients suitable for permanent vocal fold medialization are counseled about alternatives and generally treated with laryngeal framework surgery. The vocal fold position is assessed preoperatively to estimate if medialization laryngoplasty will be performed alone or in combination with arytenoid adduction. Regardless of the result of this assessment, patients are prepared for both procedures in the event that the medialization laryngoplasty alone is inadequate at the time of the surgery. Arytenoid adduction may then be performed through the same incision with only a few extra instruments required. A variety of implant materials may be used to help secure the vocal fold in the phonatory position during medialization laryngoplasty. 1 Although silastic (hardened silicone) is most widely used as an implant material, expanded polytetrafluoroethylene (ePTFE or Gore-Tex [W.L Gore and Associates, Inc, Newark, DE]) is used in the majority of medialization thyroplasties performed. 2
TECHNIQUE PREPARATION
Intravenous sedation is begun along with antibiotics and steroids. The patient may be heavily sedated during the beginning of the procedure but should be sufficiently awake toward the end to respond to verbal commands to permit assessment of the voice. The patient is positioned From the University of Iowa Hospitals and Clinics, Iowa City, IA. Address reprint requests to Henry T. Hoffman, MD, Department of Otolaryngology--Head and Neck Surgery, The University of Iowa Hospitals and Clinics, 200 Hawkins Dr, Iowa City, IA 52242. Copyright © 1999 by W.B. Saunders Company 1043-1810/99/1001-0003510.00/0 6
supine with a small shoulder roll used to slightly extend the neck. Oxygen is delivered by nasal cannula with attached CO2 monitor to the nostrils, which are topically decongested and anesthetized. Transnasal flexible fiberoptic laryngoscopy is performed before the neck incision is made to confirm the laterality of the paralysis and identify changes that may have occurred in the interval from the time of the last evaluation. The flexible fiberoptic laryngoscope is attached to a television monitor to permit all members of the operating team to view the larynx. The patient is then prepped and draped from the lower lip to below the clavicles. This permits intermittent nasal insertion of the fiberoptic laryngoscope during the procedure to assess vocal fold position as it is adjusted during the case. INITIATION OF PROCEDURE
After injection of local anesthetic, a 4- to 5-cm incision along a relaxed skin tension line is centered over the ipsilateral thyroid ala and extended slightly past midline. Subplatysmal flaps are elevated and the strap muscles are separated in the midline and retracted laterally. The local anesthetic is reinjected as the dissection is deepened. The perichondrium is elevated in a medial to lateral direction over the ipsilateral thyroid lamina. This plane of dissection permits bloodless elevation of musculature off the oblique line and inferior tubercle. If an arytenoid adduction is to be performed, the dissection is made around the posterior edge of the thyroid lamina. Medialization laryngoplasty alone may be performed without dissecting around the posterior lamina, but it is best performed with wide exposure to permit assessment of the full extent of the external cartilaginous anatomy. Placement of a tracheotomy hook or heavy suture through the laryngeal prominence permits medial retraction and rotation of the larynx to improve exposure. MEDIALIZATION LARYNGOPLASTY WITH EXPANDED POLYTETRAFLUOROETHYLENE
Like other medialization techniques, a window is created in the thyroid cartilage lateral to the membranous vocal fold to permit its medial displacement. A rotating cutting bur is used to remove a segment of thyroid cartilage positioned 1 cm posterior to the midline and 3 m m above the inferior border of the thyroid cartilage (Fig 1). A compromise is made in determining the amount of thyroid cartilage to remove The window should be sufficiently large to permit manipulation of the expanded polytetrafluoroethylene to accurately position it in the paraglottic space. A window that is too large will impair
OPERATIVE TECHNIQUES IN OTOLARYNGOLOGY--HEAD AND NECK SURGERY, VOL 10, NO 1 (MAR), 1999: PP 6-8
B
Hl_m
C
D
FIGURE 1. (A) Location of cartilage window. (B) Elevation of inner perichondrium around inferior cartilage strut. (C) Insertion of expanded polytetrafluoroethylene (ePTFE; Gore-Tex). (D) Final placement and retention around inferior strut. (Reprinted with permission from McCulloch TM, Hoffman HT: Medialization laryngoplasty with expanded polytetrafluoroethylene: Surgical technique and preliminary results. Ann Oto Rhinol Laryngo1107:427-432, 1998.)
the ability to secure the ePTFE appropriately. The thyroid cartilage surrounding the window is used as a lateral buttress to help maintain the position of the ePTFE implant. A window that is between 5 to 7 m m in vertical dimension and 10 to 12 m m in horizontal dimension is usually appropriate. The inner perichondrium is bluntly elevated circumferentially from the undersurface of the thyroid cartilage. The inferior elevation allows direct communication between the window and the cricothyroid space while an elevator is passed underneath the inferior cartilage strut. The inner perichondrium is judiciously incised to permit accurate vocal fold medialization without lateral tethering. Temporary medialization is effected by depressing the vocal fold medially with a blunt instrument placed in the window. The voice is assessed and vocal fold position reevaluated by flexible fiberoptic laryngeal examination during this trial, which helps indicate the correct location for implant placement. The implant is a 5-mm to 1-cm continuous strip (or ribbon) of ePTFE fashioned from a 0.6-mm thick cardiac patch graft (Fig 2). The implant is soaked in antibiotic solution before placement. To assure adequate implant stabilization and to maximize medialization at the appropriate inferior level, the ePTFE ribbon is wrapped once around the inferior strut of cartilage. The tail of the ribbon is then incrementally placed in the window as vocal fold position and voice are continuously assessed. This ribbon is partially secured by tucking it under the thyroid cartilage forming the edges of the window. Wedging the implant between the soft tissue of the paraglottic space medially and the thyroid cartilage laterally provides the majority of the stability to implant position. Additionally, HOFFMAN AND McCULLOCH
the implant is fixated though a 4-0 monofilament suture placed through the ePTFE circumferentially around the inferior strut and then tied on itself. The upper aspect of the implant is secured by two separate 4-0 monofilament sutures placed through the ribbon and the unossified thyroid cartilage above the window. A final endoscopic exam is then performed to confirm accurate medialization and adequate airway. The w o u n d is irrigated and closed in layers after placement of a 0.25-in Penrose drain. POSTOPERATIVE CONSIDERATIONS
The patient is observed overnight and discharged the following morning after drain removal. Oral antistaphylococcal antibiotics are continued for I week postoperatively, at which point the sutures are removed. It is not k n o w n if voice rest is critical to a good result. Our practice has been to suggest 48 hours of complete voice rest postoperatively, followed by 2 weeks of voice conservation. Repeat videostroboscopy is performed approximately 6 weeks after surgery to assess the intermediate result, focusing on the need for ancillary voice therapy. DISCUSSION
The ePTFE thyroplasty offers several advantages compared with other described techniques of medialization laryngoplasty. Use of a malleable ribbon as an implant permits incremental placement or removal as the voice and vocal cord position are dynamically assessed. Unlike preformed prostheses and segments of silastic that require modification through carving, the ePTFE implant is posi7
3 FIGURE 2. Modificationof expanded polytetrafluoroethylene
patch (ePTFE; Gore-Tex) spiral cut to form 5- to 10-ram wide ribbon. (Reprinted with permission from McCulloch TM,
Hoffman HT: Medialization laryngoplasty with expanded polytetrafl uoroethylene: Surgical technique and preliminary results. Ann Oto Rhinol Laryngol
J
J
tioned without the need to modify or change the prosthesis size. The degree of medialization is readily altered by adding or removing a portion of the continuous ribbon. Accurate positioning of the ribbon is not dependent on precise placement of the window in the thyroid cartilage. Most other techniques of medialization laryngoplasty depend on accurate location of the window directly over the segment of the vocal fold to be medialized. The technique using a ribbon of ePTFE as an implant is more flexible. Regardless of the position of the window, the implant may be placed anywhere in the paraglottic space, because it can be positioned into regions that do not immediately underlie the window. Like all medialization laryngoplasties, some edema is expected from manipulation of the vocal fold. We have
8
107:427-432, 1998.)
J
found it best to medialize the vocal fold slightly past midline in anticipation that approximately 2 to 3 mm will relapse over the ensuing months as the edema subsides. The patient is counseled preoperatively that a gradual evolution in vocal quality is expected after surgery as this edema resolves and as adaptation occurs to the new vocal fold configuration. REFERENCES 1. HoffmanHT, McCullochTM: Anatomic considerations in the surgical treatment of unilateral laryngeal paralysis. Head Neck 18:174-186,1996 2. McCulloch TM, Hoffman HT: Medialization laryngoplasty with expanded polytetrafluoroethylene:Surgical technique and preliminary results. Ann OtolRhinol Laryngo1107:427-432,1998
MEDIALIZATION LARYNGOPLASTYWITH GORE-TEX
Many techniques have been described to surgically treat symptomatic unilateral laryngeal paralysis through medialization laryngoplasty. A simplified approach that has consistently resulted in good vocal results is presented.
Although there is still no critical comparative analysis to define the best surgical approach to treating laryngeal paralysis, the best long-term phonatory results come from medialization laryngoplasty, often coupled with arytenoid adduction. Arytenoid adduction, when performed in isolation, does not consistently provide adequate glottic closure. It is best suited to position the vocal process in the phonatory position, but it does not always result in adequate medial positioning of the membranous vocal cord. A significant portion of the patients treated with arytenoid adduction alone have subsequently needed further treatment of the anterior glottis with either a fat injection or medialization laryngoplasty. As a result, most of the patients now treated with arytenoid adduction receive a concomitant medialization laryngoplasty. Those patients suitable for permanent vocal fold medialization are counseled about alternatives and generally treated with laryngeal framework surgery. The vocal fold position is assessed preoperatively to estimate if medialization laryngoplasty will be performed alone or in combination with arytenoid adduction. Regardless of the result of this assessment, patients are prepared for both procedures in the event that the medialization laryngoplasty alone is inadequate at the time of the surgery. Arytenoid adduction may then be performed through the same incision with only a few extra instruments required. A variety of implant materials may be used to help secure the vocal fold in the phonatory position during medialization laryngoplasty. 1 Although silastic (hardened silicone) is most widely used as an implant material, expanded polytetrafluoroethylene (ePTFE or Gore-Tex [W.L Gore and Associates, Inc, Newark, DE]) is used in the majority of medialization thyroplasties performed. 2
TECHNIQUE PREPARATION
Intravenous sedation is begun along with antibiotics and steroids. The patient may be heavily sedated during the beginning of the procedure but should be sufficiently awake toward the end to respond to verbal commands to permit assessment of the voice. The patient is positioned From the University of Iowa Hospitals and Clinics, Iowa City, IA. Address reprint requests to Henry T. Hoffman, MD, Department of Otolaryngology--Head and Neck Surgery, The University of Iowa Hospitals and Clinics, 200 Hawkins Dr, Iowa City, IA 52242. Copyright © 1999 by W.B. Saunders Company 1043-1810/99/1001-0003510.00/0 6
supine with a small shoulder roll used to slightly extend the neck. Oxygen is delivered by nasal cannula with attached CO2 monitor to the nostrils, which are topically decongested and anesthetized. Transnasal flexible fiberoptic laryngoscopy is performed before the neck incision is made to confirm the laterality of the paralysis and identify changes that may have occurred in the interval from the time of the last evaluation. The flexible fiberoptic laryngoscope is attached to a television monitor to permit all members of the operating team to view the larynx. The patient is then prepped and draped from the lower lip to below the clavicles. This permits intermittent nasal insertion of the fiberoptic laryngoscope during the procedure to assess vocal fold position as it is adjusted during the case. INITIATION OF PROCEDURE
After injection of local anesthetic, a 4- to 5-cm incision along a relaxed skin tension line is centered over the ipsilateral thyroid ala and extended slightly past midline. Subplatysmal flaps are elevated and the strap muscles are separated in the midline and retracted laterally. The local anesthetic is reinjected as the dissection is deepened. The perichondrium is elevated in a medial to lateral direction over the ipsilateral thyroid lamina. This plane of dissection permits bloodless elevation of musculature off the oblique line and inferior tubercle. If an arytenoid adduction is to be performed, the dissection is made around the posterior edge of the thyroid lamina. Medialization laryngoplasty alone may be performed without dissecting around the posterior lamina, but it is best performed with wide exposure to permit assessment of the full extent of the external cartilaginous anatomy. Placement of a tracheotomy hook or heavy suture through the laryngeal prominence permits medial retraction and rotation of the larynx to improve exposure. MEDIALIZATION LARYNGOPLASTY WITH EXPANDED POLYTETRAFLUOROETHYLENE
Like other medialization techniques, a window is created in the thyroid cartilage lateral to the membranous vocal fold to permit its medial displacement. A rotating cutting bur is used to remove a segment of thyroid cartilage positioned 1 cm posterior to the midline and 3 m m above the inferior border of the thyroid cartilage (Fig 1). A compromise is made in determining the amount of thyroid cartilage to remove The window should be sufficiently large to permit manipulation of the expanded polytetrafluoroethylene to accurately position it in the paraglottic space. A window that is too large will impair
OPERATIVE TECHNIQUES IN OTOLARYNGOLOGY--HEAD AND NECK SURGERY, VOL 10, NO 1 (MAR), 1999: PP 6-8
B
Hl_m
C
D
FIGURE 1. (A) Location of cartilage window. (B) Elevation of inner perichondrium around inferior cartilage strut. (C) Insertion of expanded polytetrafluoroethylene (ePTFE; Gore-Tex). (D) Final placement and retention around inferior strut. (Reprinted with permission from McCulloch TM, Hoffman HT: Medialization laryngoplasty with expanded polytetrafluoroethylene: Surgical technique and preliminary results. Ann Oto Rhinol Laryngo1107:427-432, 1998.)
the ability to secure the ePTFE appropriately. The thyroid cartilage surrounding the window is used as a lateral buttress to help maintain the position of the ePTFE implant. A window that is between 5 to 7 m m in vertical dimension and 10 to 12 m m in horizontal dimension is usually appropriate. The inner perichondrium is bluntly elevated circumferentially from the undersurface of the thyroid cartilage. The inferior elevation allows direct communication between the window and the cricothyroid space while an elevator is passed underneath the inferior cartilage strut. The inner perichondrium is judiciously incised to permit accurate vocal fold medialization without lateral tethering. Temporary medialization is effected by depressing the vocal fold medially with a blunt instrument placed in the window. The voice is assessed and vocal fold position reevaluated by flexible fiberoptic laryngeal examination during this trial, which helps indicate the correct location for implant placement. The implant is a 5-mm to 1-cm continuous strip (or ribbon) of ePTFE fashioned from a 0.6-mm thick cardiac patch graft (Fig 2). The implant is soaked in antibiotic solution before placement. To assure adequate implant stabilization and to maximize medialization at the appropriate inferior level, the ePTFE ribbon is wrapped once around the inferior strut of cartilage. The tail of the ribbon is then incrementally placed in the window as vocal fold position and voice are continuously assessed. This ribbon is partially secured by tucking it under the thyroid cartilage forming the edges of the window. Wedging the implant between the soft tissue of the paraglottic space medially and the thyroid cartilage laterally provides the majority of the stability to implant position. Additionally, HOFFMAN AND McCULLOCH
the implant is fixated though a 4-0 monofilament suture placed through the ePTFE circumferentially around the inferior strut and then tied on itself. The upper aspect of the implant is secured by two separate 4-0 monofilament sutures placed through the ribbon and the unossified thyroid cartilage above the window. A final endoscopic exam is then performed to confirm accurate medialization and adequate airway. The w o u n d is irrigated and closed in layers after placement of a 0.25-in Penrose drain. POSTOPERATIVE CONSIDERATIONS
The patient is observed overnight and discharged the following morning after drain removal. Oral antistaphylococcal antibiotics are continued for I week postoperatively, at which point the sutures are removed. It is not k n o w n if voice rest is critical to a good result. Our practice has been to suggest 48 hours of complete voice rest postoperatively, followed by 2 weeks of voice conservation. Repeat videostroboscopy is performed approximately 6 weeks after surgery to assess the intermediate result, focusing on the need for ancillary voice therapy. DISCUSSION
The ePTFE thyroplasty offers several advantages compared with other described techniques of medialization laryngoplasty. Use of a malleable ribbon as an implant permits incremental placement or removal as the voice and vocal cord position are dynamically assessed. Unlike preformed prostheses and segments of silastic that require modification through carving, the ePTFE implant is posi7
3 FIGURE 2. Modificationof expanded polytetrafluoroethylene
patch (ePTFE; Gore-Tex) spiral cut to form 5- to 10-ram wide ribbon. (Reprinted with permission from McCulloch TM,
Hoffman HT: Medialization laryngoplasty with expanded polytetrafl uoroethylene: Surgical technique and preliminary results. Ann Oto Rhinol Laryngol
J
J
tioned without the need to modify or change the prosthesis size. The degree of medialization is readily altered by adding or removing a portion of the continuous ribbon. Accurate positioning of the ribbon is not dependent on precise placement of the window in the thyroid cartilage. Most other techniques of medialization laryngoplasty depend on accurate location of the window directly over the segment of the vocal fold to be medialized. The technique using a ribbon of ePTFE as an implant is more flexible. Regardless of the position of the window, the implant may be placed anywhere in the paraglottic space, because it can be positioned into regions that do not immediately underlie the window. Like all medialization laryngoplasties, some edema is expected from manipulation of the vocal fold. We have
8
107:427-432, 1998.)
J
found it best to medialize the vocal fold slightly past midline in anticipation that approximately 2 to 3 mm will relapse over the ensuing months as the edema subsides. The patient is counseled preoperatively that a gradual evolution in vocal quality is expected after surgery as this edema resolves and as adaptation occurs to the new vocal fold configuration. REFERENCES 1. HoffmanHT, McCullochTM: Anatomic considerations in the surgical treatment of unilateral laryngeal paralysis. Head Neck 18:174-186,1996 2. McCulloch TM, Hoffman HT: Medialization laryngoplasty with expanded polytetrafluoroethylene:Surgical technique and preliminary results. Ann OtolRhinol Laryngo1107:427-432,1998
MEDIALIZATION LARYNGOPLASTYWITH GORE-TEX