颈袢主支吻合术治疗单侧声带麻痹的临床观察

采用颈袢主支与喉返神经内收肌支吻合术治疗单侧声带麻痹７例。结果表明，声音恢复满意。术后声学三参数频率微扰、振幅微扰及标化噪音能量均明显减小，平均值均在正常范围之内；喉镜检查发现术侧声带均有不同程度的内移，其中３例恢复至正中位；喉肌电图显示，发音及喉括约活动时术侧喉内收肌恢复与健侧基本同步的密集型强放电，证明术侧喉内收肌获得颈袢主支有效的神经再支配。提示该术是治疗单侧声带麻痹一种理想方法。     

颈袢主支与喉返神经内收肌支吻合术治疗喉麻痹的实验研究

建立单侧喉麻痹模型，实验组作颈袢主支与喉返神经（ＲＬＮ）内收肌支吻合术，对照组不作神经修复术。６个月后行喉镜、肌电图、组织化学检查及肌收缩力测定，证实实验组动物声带内收肌获得有效的再神经支配，声带内收为颈袢主支支配的结果。对照组无再神经支配征象。提示颈袢主支与ＲＬＮ内收肌支吻合术治疗单侧喉麻痹是一较为理想的手术方法。     

延期神经吻合术重建声带内收功能的实验研究

建立单侧喉麻痹动物模型，实验组喉麻痹后不同时间作颈袢主支与喉返神经内收肌支的延期吻合术。术后６个月，发现喉麻痹６、８、１０个月作神经吻合术的动物声带能恢复不同程度的内收功能，肌张力为健侧的６０％以上，内收肌运动终板分布、形态基本正常。喉麻痹１２、１８个月作神经吻合术的动物声带固定，肌张力为健侧的２３～５４％，内收肌运动终板分布弥散，但仍很丰富，肌纤维结构良好。行神经吻合的动物均恢复一定程度的诱发肌电图去极化幅度。结果表明，延期神经吻合术能使内收肌获得再神经支配，并恢复部分喉功能。     

延期神经吻合术重建声带内收功能的实验研究

建立单侧喉麻痹动物模型，实验组喉麻痹后不同时间作颈袢主支与喉返神经内收肌支的延期吻合术，术后６个月，发现喉麻痹６、８、１０个月作神经吻合术的动物声带能恢复不同程度的内收功能，肌张力为健侧的６０％以上，内收肌运动终板分布，形态长期基本正常，喉麻痹１２、１８个月作神经吻合术的动物志带固定，肌张力为健侧的２３－５４％，内收肌运动终板分布弥散，但仍很丰富，肌纤维结构良好，行神经吻合的动物均恢复一定程度的诱     

神经肌蒂移植同时恢复麻痹声带内收及外展功能的实验研究

目的 探索一种能同时恢复麻痹声带内收及外展功能的治疗方法。方法 对狗一侧喉返神经及喉上神经运动支联合麻痹的喉内肌,采用颈袢胸骨甲状肌肌蒂移植于麻痹环杓后肌,颈袢甲状舌骨肌肌蒂移植于麻痹侧环杓侧肌作为实验组,并仅用颈袢胸骨甲状肌肌蒂移植于麻痹侧环杓后肌作为对照组。术前及术后４个月行声带录像、喉肌电图检测、组织学检查。结果术后４个月所有动物均不同程度地恢复了麻痹声带的生物功能。实验组术侧声带内运动明显     

颈袢亚分支植入术治疗单侧喉麻痹的实验研究

用１１只狗，分成实验组（７只）及对照组（４只），均切断左侧喉返神经和左侧喉上神经外支造成单侧喉麻痹。实验组将颈袢（舌下神经袢）主支的各亚分支植入声带内收肌中，对照组不作此神经修复术，６个月后行喉镜检查，喉肌电图检查，肌收缩力测定，组织化学检查及运动终板细胞化学电镜观察，证实实验组声带内收肌获得有效的再神经支配，声带内收为颈袢亚分支再神经支配的结果，未见吸气性声带内收现象。对照组声带内收肌无再神经支     

杓状软骨内移联合喉返神经修复术治疗单侧声带麻痹

目的 探讨杓状软骨内移联合颈袢喉返神经吻合术治疗长期喉返神经损伤单侧声带麻痹的疗效.方法 病程3～22年外伤性喉返神经损伤单侧声带麻痹患者12例,行患侧杓状软骨内移的同时,作颈袢喉返神经吻合术.治疗前后以电子喉镜、频闪喉镜、声音评估、嗓音声学参数分析和喉肌电图检查等评价治疗效果.结果 所有患者杓状软骨内移术后即刻声嘶均明显好转,但无恢复正常者,声学四参数频率微扰、振幅微扰、标化噪音能量和最长发声时间分析均明显好转,差异均有显著性意义(P值均＜0.05);喉镜检查见杓状软骨明显内移,声门后裂隙消失9例,缩小3例.术后12个月时声音恢复正常、明显好转、好转、无改善分别为9、3、0、0例;声学四参数较术后即刻又有明显好转,差异均有显著性意义(P值均＜0.05);术侧声带虽未恢复运动,但肌张力和肌体积与健侧基本对称.肌电图检查显示术后12个月声带肌恢复与健侧同步的密集型自发电位.结论 杓状软骨内移联合颈袢喉返神经吻合治疗长期喉返神经损伤单侧声带麻痹能恢复患者的正常发音功能.     

单侧喉返神经损伤神经修复术式探讨

目的 探讨5种神经修复术治疗单侧喉返神经损伤声带麻痹的疗效。方法 1993年1月－2001年4月治疗外伤性单侧喉返神经损伤声带麻痹38例，病程从损伤即刻至2年不等。资料完整者35例，其中行神经减压术8例、颈襻主支喉返神经吻合术16例、喉返神经端端吻合术6例、颈襻神经肌蒂埋植术3例、颈襻神经植入术2例。手术前后喉镜、噪音声学参数、肌电图检查等评价手术效果。结果 病程4个月内神经减压5例恢复了正常的声带内收及外展功能，4个月以内1例、以上2例及颈襻主支吻合组、喉返神经端端吻合组则未恢复声带运动。但上述3例术式均能使喉内收肌获有效的再神经支配，满意地恢复声带的肌张力、肌体积、声带振动对称性及正常黏膜波，声门闭合良好，嗓音恢复正常。颈襻神经肌蒂埋植术及颈襻神经植入术均能改善声嘶，但无效复正常病例。结论 ①单侧喉返神经损伤神经修复治疗以神经减压效果最佳；②颈襻主支吻合术、喉返神经端端吻合术也能有效地恢复喉的发音功能；③喉神经修复术式选择应根据病程、神经损伤程度、类型而定。     

单侧喉返神经损伤神经修复术式探讨

目的　探讨 5种神经修复术治疗单侧喉返神经损伤声带麻痹的疗效。方法　 1993年 1月～ 2 0 0 1年 4月治疗外伤性单侧喉返神经损伤声带麻痹 38例 ,病程从损伤即刻至 2年不等。资料完整者 35例 ,其中行神经减压术 8例、颈襻主支喉返神经吻合术 16例、喉返神经端端吻合术 6例、颈襻神经肌蒂埋植术 3例、颈襻神经植入术 2例。手术前后喉镜、嗓音声学参数、肌电图检查等评价手术效果。结果　病程 4个月内神经减压 5例恢复了正常的声带内收及外展功能 ,4个月以内 1例、以上2例及颈襻主支吻合组、喉返神经端端吻合组则未恢复声带运动。但上述 3种术式均能使喉内收肌获有效的再神经支配 ,满意地恢复声带的肌张力、肌体积、声带振动对称性及正常黏膜波 ,声门闭合良好 ,嗓音恢复正常。颈襻神经肌蒂埋植术及颈襻神经植入术均能改善声嘶 ,但无恢复正常病例。结论　①单侧喉返神经损伤神经修复治疗以神经减压效果最佳 ;②颈襻主支吻合术、喉返神经端端吻合术也能有效地恢复喉的发音功能 ;③喉神经修复术式选择应根据病程、神经损伤程度、类型而定     

甲状腺手术喉返神经损伤的神经修复治疗

目的探讨甲状腺手术所致喉返神经损伤的神经修复治疗。方法选取2008年10月～2013年4月收治的甲状腺术后喉返神经损伤患者4l例,行喉返神经减压术23例,行喉返神经端端吻合术11例,行颈袢主支喉返神经吻合术7例。结果喉返神经减压组17例、喉返神经端端吻合组6例及颈袢主支喉返神经吻合组2例,于术后半年内麻痹声带恢复内收及外展运动;吸气时外展幅度基本对称;发音时声带内收于正中位,双侧声带长度及体积对称,声门闭合无裂隙。喉返神经减压组患者声带黏膜波及声带振动恢复了对称性。喉返神经端端吻合组及颈袢主支喉返神经吻合组患者声带黏膜波、声带振动基本对称。喉返神经减压组患者声音均恢复正常。喉返神经端端吻合组8例、颈袢主支喉返神经神经吻合组4患者声音恢复正常;喉返神经端端吻合组3例、颈袢主支喉返神经吻合组3患者声嘶明显改善。结论神经修复治疗甲状腺手术所致喉返神经损伤疗效确切,以神经减压术效果最佳。     

Update: Laryngeal Reinnervation for Unilateral Vocal Cord Paralysis With the Ansa Cervicalis

Eight patients underwent ansa cervicalis anastomosis to the adductor branch of the recurrent laryngeal nerve for unilateral vocal cord paralysis. They were followed long enough (at least 1 year) to determine if the procedure was successful. All cases have been subjected to preoperative and postoperative voice recording, acoustic analysis, and videolaryngoscopy. Some of them have been subjected to stroboscopy and electromyography (EMG). Data from these cases indicate that satisfactory phonatory quality may be achieved after the procedure. The reinnervated vocal cord neither abducted nor adducted, but it presented itself in midline for precise apposition with the normal cord. Synchronous mucosal waves in both vocal cords could be observed. EMG showed that the procedure produced satisfactory reinnervation of the adductory muscles. Therefore, the authors believe that the procedure could be proposed as an alternative to Teflon injection or thyroplasty in selected cases.     

Update: Ansa Cervicalis to Recurrent Laryngeal Nerve Anastomosis for Unilateral Laryngeal Paralysis

Twenty cases of unilateral laryngeal paralysis are reported. Satisfactory follow-up intervals and data (videostroboscopy and glottographic analysis) were available on 12 patients. The excellent to normal phonatory quality achieved in many of these patients indicates that the ansa cervicalis to recurrent laryngeal nerve anastomosis is the procedure of choice in selected patients with unilateral vocal cord paralysis. Excellent medialization of the paralyzed cord, as well as correction of arytenoid malposition and thyroarytenoid muscle atrophy appear to explain the technique's success, since the reinnervated cord neither abducts nor adducts. We feel that this technique is the procedure of choice in younger patients, or those who use their voices professionally, since the phonatory quality achieved is superior to Teflon® injection or Isshiki thyroplasty, and the technique is reversible.     

Experimental Study on Reinnervation of Vocal Cord Adductors With the Ansa Cervicalis

The purpose of this study was to reestablish the adduction of the paralyzed vocal cord through reinnervation of the adductor muscles for unilateral vocal cord paralysis. In nine dogs, the adductor branch of the recurrent laryngeal nerve was anastomosed to the main branch of the ansa cervicalis. Six months later, various techniques of observation showed that seven of nine cases had excellent to good adduction during whining. Adduction was caused by reinnervation of the adductor muscles from the ansa cervicalis as demonstrated by laryngeal spontaneous and evoked electromyography, contraction tension, and various histologic findings. Therefore, the new technique could be a good treatment of unilateral vocal cord paralysis.     

Inspiratory activation of the vocal cord adductor, part II: Animal study in the cat

OBJECTIVES/HYPOTHESIS: The authors have shown previously that the vocal cord adductor is activated during inspiration in patients with vocal cord abduction impairment and that this adductor inspiratory activity is abolished by relief from inspiratory tracheal negative pressure by opening the tracheostoma. (Shiba K. Isono S, Sekita Y, Tanaka A. Inspiratory activation of the vocal cord adductor, Part I: human study in patients with restricted abduction of the vocal cords. Laryngoscope 2004;114:372-375). The authors hypothesized that insufficient opening of the glottis during inspiration generates strong negative pressure in the trachea and that this negative pressure triggers an airway reflex that activates the adductor. STUDY DESIGN: Experimental study of the mechanism of laryngeal obstruction using an animal model of restricted abduction of the vocal cords. METHODS: To identify such an airway reflex, the authors recorded the adductor electromyogram in anesthetized cats whose vocal cords were mechanically adducted by stitching both cords together. To determine whether this reflex modulation of adductor activity is induced through afferents from the larynx or from the lower airway, the authors applied negative pressure to the subglottic space and lower airway separately. RESULTS: The adductor was activated during inspiration with powerful negative pressure in the trachea. Negative pressure in the subglottic space had a more marked effect on the adductor activity than did pressure in the lower airway. The adductor inspiratory activity was virtually abolished by laryngeal deafferentation. CONCLUSION: Glottal narrowing during inspiration reflexly activates the vocal cord adductor. This paradoxical inspiratory-related adductor activation is induced by an airway reflex triggered mainly through afferents from the larynx and probably contributes to stridor and dyspnea in patients with laryngeal obstruction.     

Nerve transfer versus Teflon injection for vocal cord paralysis: a comparison

Teflon injection for unilateral vocal cord paralysis frequently produces an improved yet breathy voice. Ansa hypoglossi-recurrent laryngeal nerve anastomosis has been performed in five patients. In the four patients discussed in this paper, excellent phonatory quality has been achieved. Electroacoustic analysis indicates that this technique may produce normal phonatory function in paralyzed larynges. There have been no serious side effects or complications in our first five patients. Denervation of the sternothyroid muscle, which results from sectioning its nerve in preparation for suture to the RLN, appears to further improve the voice by medially positioning the vocal cord. Gelfoam paste is injected at the time of nerve transfer to rehabilitate the voice during the 2 months required for nerve regeneration. For younger patients, or those with professional use of their voices, this technique offers superior speech results when compared with Teflon injection.     

Laryngeal electromyographic activity in adductor and abductor spasmodic dysphonia

Vocal symptoms in spasmodic dysphonia (SD) range from strain-strangle phonation and glottal-stop phonatory breaks of adductor SD to breathy phonation and aspirate phonatory breaks of abductor SD. Many SD subjects show both symptom types. Heterogeneity in vocal symptoms contributes to controversy surrounding the etiology(s) of SD. Acoustic/perceptual analyses of vocal symptoms are inconclusive in resolving this controversy. This investigation moves the search for distinguishing features of adductor and abductor SD to the level of neuromuscular control and analysis of intrinsic laryngeal muscle (adductor and abductor) activity. Subjects rated perceptually as primarily adductor or abductor SD sustained production of vegetative gestures and isolated speech sounds (/i/ and /s/). Qualitative and quantitative analyses of electromyographic signals recorded from thyroarytenoid (TA) failed to differentiate SD subjects by symptom type. Analysis of TA and posterior cricoarytenoid (PCA) activity in one abductor SD revealed high levels in both muscles during production of the voiced vowel. Data suggest that a possible explanation for symptom heterogeneity in SD is the relation between disrupted neuromotor input to laryngeal muscles and reflexive or conscious compensations constrained by laryngeal biomechanics.     

Experimental study on simultaneous selective reinnervation of the adductors and the abductor muscle for the treatment of the laryngeal paralysis

OBJECTIVE: The aim of this study is to estimate the value of a new surgical procedure in the treatment of the chronic unilateral laryngeal paralysis. METHODS: The recurrent laryngeal nerve of the left side of the dog was totally cut and served as a model of unilateral laryngeal paralysis at the first step of the research. The adductor and abductor branches of the recurrent laryngeal nerve were then, selected and cut. Afterwards, they were micro-sutured respectively with one branch of ansa cervicalis and phrenic nerve immediately (group 1) and 4 months later (group 2). Six months after this reinnervation, the laryngeal physiologic function of the lateral crico-arytenoid muscle (LCA) and the posterior crico-arytenoid muscle (PCA) have been checked by the methods of electromyography (EMG) and direct laryngoscopy. All the data have been analysed by the statistic methods. RESULTS: Among all the data of EMG, only the wave amplitude of action potential of the LCA muscle of the group 2 was diminished (p < 0.05). Under the direct laryngoscopy, the adductor movement of the left vocal cord of the group 2 was also lightly reduced. But the adductor and abductor movements of the left vocal cord were synchronous with the mouvements of the right vocal cord. CONCLUSION: Though the result of nervous reinnervation of a four month's laryngeal paralysis was not so good by comparison with that of an immediate reinnervation, this surgical procedure can however on the clinical point of view, reach a satisfactory level. The duration maximum of the reinnervation operation after laryngeal paralysis, is, at the present, not clear. It is necessary for us to make further studies.     

Inspiratory activation of the vocal cord adductor, part I: human study in patients with restricted abduction of the vocal cords

OBJECTIVES/HYPOTHESIS: In patients with restricted abduction of the vocal cords, it has generally been accepted that glottis narrowing with laryngeal stridor during inspiration is attributed to static and passive obstruction of the glottis. However, active glottis narrowing can also be contributory. We tested the hypothesis that the vocal cord adductor is activated during inspiration in patients with restricted abduction of the vocal cords. STUDY DESIGN: Electromyographic evaluation of vocal cord adductor activity in patients with restricted abduction of the vocal cords. METHODS: Five patients with restricted abduction of the vocal cords who had stridor with mild to severe dyspnea during wakefulness were anesthetized with propofol. We recorded the adductor muscle electromyogram during breathing through a laryngeal mask airway while observing the vocal cord movement endoscopically. In three patients who had undergone tracheostomy, we also recorded adductor firing patterns not only while closing but also while opening the tracheostoma. RESULTS: The adductor was activated during inspiration, and the glottis was narrowed in accordance with inspiratory stridor. This adductor inspiratory activity was abolished by opening the tracheostoma in the tracheostomized patients. CONCLUSION: Not only static or passive glottis narrowing but also active narrowing may contribute to inspiratory flow limitation in patients with restricted abduction of the vocal cords. This active glottis narrowing is probably induced by an airway reflex.     

Lidocaine block of the recurrent laryngeal nerve in adductor spasmodic dysphonia: a multidimensional assessment

OBJECTIVES/HYPOTHESIS: Lidocaine block of the recurrent laryngeal nerve (RLN) has been reported as a procedure for surgical selection of patients with adductor spasmodic dysphonia (ADSD). However, its effects on phonation have not been rigorously assessed in a prospective fashion using strict entry criteria and multiple measures of phonatory function. This investigation assessed the phonatory effects of RLN lidocaine block in ADSD to explore its potential as a diagnostic tool. STUDY DESIGN: Single group, pre/postexperimental trial. METHODS: Twenty-one consecutive patients with suspected ADSD underwent unilateral RLN block, causing temporary ipsilateral vocal fold paralysis. Voices were recorded before and during the block. Patients completed self-ratings of overall level of dysphonia severity, vocal effort, and laryngeal tightness. Blinded listeners completed auditory-perceptual ratings, and the frequency of phonatory breaks was acoustically analyzed. RESULTS: During the block, patients reported significant reductions on overall severity (P = .045), vocal effort (P < .001), and laryngeal tightness (P = .002). Listeners rated the voices during the block as significantly more breathy (P < .001), less strained (P < .001), and less severe (P = .059). Acoustic analysis confirmed significantly fewer phonatory breaks during the block (P < .001). Patient-based ratings of improvement were more consistent than listener ratings, and reduction in overall severity correlated with perceived breathiness. CONCLUSIONS: Although individuals varied in their outcomes, group results suggest that response to RLN lidocaine block warrants further study as a possible diagnostic tool in ADSD.     

Laryngeal synkinesis: its significance to the laryngologist

Basic research and surgical cases have shown that the injured recurrent laryngeal nerve (RLN) may regenerate axons to the larynx that inappropriately innervate both vocal cord adductors and abductors. Innervation of vocal cord adductor muscles by those axons that depolarize during inspiration is particularly devastating to laryngeal function, since it produces medial vocal cord movement during inspiration. Many patients thought to have clinical bilateral vocal cord paralysis can be found to have synkinesis on at least one side. This will make the glottic airway smaller, particularly during inspiration, than would true paralysis of all the intrinsic laryngeal muscles. Patients with bilateral vocal cord paralysis should undergo laryngeal electromyography. If inspiratory innervation of the adductor muscles is present, simple reinnervation of the posterior cricoarytenoid muscle will fail. The adductor muscles also must be denervated by transection of the adductor division of the regenerated RLN.