ORIGINAL ARTICLE Nerve-Muscle Pedicle Flap Implantation Combined With Arytenoid Adduction Eiji Yumoto, MD; Tetsuji Sanuki, MD; Yutaka Toya, MD; Narihiro Kodama; Yoshihiko Kumai, MD Objectives: To describe a new technique of nerve- Main Outcome Measures: The maximum phonation muscle pedicle (NMP) flap implantation combined with time, mean airflow rate, pitch range, and acoustic para- arytenoid adduction (AA) to treat dysphonia due to uni- meters (jitter, shimmer, and harmonics to noise ratio) were lateral vocal fold paralysis and to examine postoperative evaluated before surgery and twice after surgery. vocal function. Results: All parameters improved significantly after sur- Study Design: Retrospective review of clinical gery (PϽ.01). The measurements for maximum phonation records. time, mean airflow rate, and harmonics to noise ratio were within normal ranges after surgery. Furthermore, the maxi- Setting: Tertiary academic center. mum phonation time and jitter were significantly improved after long-term follow-up compared with early postopera- Patients: Twenty-two consecutive patients underwent tive measurements (PϽ.01 and PϽ.05, respectively). NMP flap implantation with AA and were followed up short term over a period of 1 to 6 months (mean, 2.9 Conclusions: Precise harvest of an NMP flap and its place- months) and long term over a period of 7 to 36 months ment directly onto the thyroarytenoid muscle combined (mean, 21.4 months). with AA provided excellent vocal function. The NMP Interventions: An NMP flap was made using an ansa cer- method may have played a certain role in the improve- vicalis branch and a piece of the sternohyoid muscle. A win- ment of postoperative vocal function, although further study dow was opened in the thyroid ala at the level of the vocal with electromyographic examination is required to clarify fold. Then, AA was performed and the NMP flap was se- the innervation status of the thyroarytenoid muscle. curely implanted onto the thyroarytenoid muscle through the window under microscopic guidance. Arch Otolaryngol Head Neck Surg. 2010;136(10):965-969 MPROVEMENT IN BREATHY DYSPHO- muscle pedicle (NMP) flap implantation nia due to unilateral vocal fold pa- onto the TA muscle through a window in ralysis (UVFP) is usually achieved the thyroid ala. May and Beery4 also re- by implementing various kinds of ported positive effects of NMP implanta- phonosurgical procedures, in- tion onto the lateral cricoarytenoid muscle Icluding intracordal injection, type I thy- on breathy dysphonia. However, to our roplasty, arytenoid adduction (AA), and knowledge, no studies, except those noted combinations thereof. However, some pa- above, have reported further results regard- tients do not recover “normal” voices af- ing the use of the NMP method. Although ter surgery.1,2 Normal voices can be at- immediate reconstruction of the severed re- tained by providing the immobile vocal current laryngeal nerve (RLN) can result in fold with the median location and the excellent vocal function,5 immediate recon- struction is not feasible in most patients be- cause they usually seek treatment only af- Video available online at ter the onset of paralysis. We examined the www.archoto.com effects of an NMP method in rats and con- firmed the effectiveness of the method to re- symmetrical bulk and tension of the unaf- verse or repair atrophic changes in the long- fected vocal fold. Because the phonosurgi- term denervated TA muscle.6,7 We refined cal procedures offer “static” adjustment of the technique of NMP flap implantation these features, the thyroarytenoid muscle onto the TA muscle and have applied this Author Affiliations: Department of (TA) does not work as the body of the im- innovative method, together with AA, in the Otolaryngology–Head and Neck mobile vocal fold, resulting in little contri- treatment of breathy dysphonia due to Surgery, Graduate School of bution to voice production and tuning. UVFP since July 2002. We also refined the Medicine, Kumamoto To restore tonus of the immobile vocal original AA method of Isshiki et al.8 The University, Kumamoto, Japan. fold, Tucker3 described a method of nerve- goals of the present study were to describe (REPRINTED) ARCH OTOLARYNGOL HEAD NECK SURG/ VOL 136 (NO. 10), OCT 2010 WWW.ARCHOTO.COM 965 ©2010 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 10/01/2021 Cranial side Thyroid notch Cranial side 10-12 mm 2 mm 5-7 mm 3-5 mm Inferior tubercle Figure 3. An operative view after completion of arytenoid adduction in the same patient as in Figure 1. The dotted line indicates the estimated level of Inferior tubercle the vocal fold. The asterisks indicate the silicone shim; arrowheads, the exposed thyroarytenoid muscle. Figure 1. Location and design of the window in the thyroid ala (58-year-old man, left side). The dotted line indicates the estimated level of the vocal fold. respectively. The use of a relatively thin tube allows the vocal fold to adduct passively through the anteroinferior pull of the Cranial side muscular process of the arytenoid cartilage. An incision is made horizontally from the midline to the anterior margin of the sternocleidomastoid muscle at the level of the inferior one-fourth of the thyroid cartilage. The space anterior to the sternocleidomastoid muscle is opened, expos- ing the internal jugular vein where the ansa cervicalis (AC) nerve (superior root) and its branch to the omohyoid muscle are iden- tified. The omohyoid muscle is transected, and the AC nerve is followed until it enters the sternohyoid (SH) muscle. Elec- trical stimulation is applied to confirm the presence of nerve fibers innervating the SH muscle. A relatively thick AC branch to the SH muscle is harvested together with a 3ϫ3-mm piece of the muscle at the point of nerve entrance to the muscle to form a NMP flap. The NMP flap is elevated with meticulous care, and the course is reversed cranially so that the NMP flap Nerve-muscle pedicle flap reaches the midportion of the thyroid ala with no tension. The Figure 2. A nerve-muscle pedicle flap, which reached the window without inferior root of the AC nerve is usually preserved. tension in the same patient as in Figure 1. Cartilage is not yet drilled out. Arytenoid adduction is performed according to the method of Isshiki et al.8 The cricoarytenoid joint is not opened in our technique. Care is taken to preserve the external branch of the our refined technique in detail and to report patient data superior laryngeal nerve and to avoid injury to the pyriform from vocal function tests. The study was approved by the sinus mucosa. The muscular process is grasped with a pair of institutional review board of the Graduate School of Medi- Adson forceps to confirm the passive mobility of the aryte- cine, Kumamoto University. noid. This step is necessary to estimate the degree of traction of the muscular process. Two 3-0 nylon threads are then placed METHODS through the muscular process and tied for later use. The location and design of a window in the thyroid ala is shown in Figure 1. The window base is set 2 to 3 mm cranial PATIENTS to the lower edge of the thyroid ala. Diamond-tip drills are used under microscopic control to make a window with the inner Twenty-four consecutive patients with breathy dysphonia due perichondrium intact. Figure 2 shows the NMP flap, which to UVFP underwent NMP flap implantation together with AA reaches the window without tension. After the cartilage in the between July 2002 and September 2007 at Kumamoto Univer- window is drilled out, the perichondrium is excised with elec- sity Hospital, Kumamoto, Japan. Two patients, however, were trocautery, and the TA muscle is carefully exposed as wide as excluded. One patient with left vocal fold paralysis underwent possible to secure contact of the NMP flap with the TA muscle. total thyroidectomy simultaneously; the next day, she under- The nylon thread tied to the muscular process is intro- went a tracheostomy because of paralysis of the preopera- duced to the anterior surface of the thyroid ala medially from tively mobile right vocal fold. Another patient was not fol- the inferior tubercle, with one end through the lower edge of lowed up for the requisite time. Therefore, our study included the window and the other end through the cricothyroid mem- 22 patients who were followed up for more than 6 months. brane. Another thread is also introduced in the same way, slightly more medially. These threads pull the muscular process in a SURGICAL PROCEDURE direction similar to the lateral cricoarytenoid muscle and are secured using a silicone shim. Figure 3 shows a picture after General anesthesia with endotracheal intubation is adminis- completion of AA. The TA muscle bundle is widely exposed tered. The patient lies in the supine position with a pillow un- (Figure 3, arrowheads). der the shoulder. Generally, an endotracheal tube with an in- The muscle piece of the NMP flap is positioned in the win- ner diameter of 6 or 7 mm is used for female or male patients, dow to make as wide contact as possible with the TA muscle (REPRINTED) ARCH OTOLARYNGOL HEAD NECK SURG/ VOL 136 (NO. 10), OCT 2010 WWW.ARCHOTO.COM 966 ©2010 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 10/01/2021 and is secured with the surrounding tissues using 8-0 nylon threads. This step is crucial and is performed under micro- Cranial side scopic guidance. Subsequently, the window is covered with the outer perichondium (Figure 4). Meticulous hemostasis is un- dertaken throughout the operation. Two Penrose drains are placed in the wound, one at the site of the NMP flap harvest and the other toward the paraglottic space.