Laryngeal Reinnervation Research Articles

A meta-analysis on the improvement of vocal function in unilateral vocal cord paralysis by reinnervation of the recurrent laryngeal nerve

Objective:To conduct a systematic description and meta-analysis of the treatment of unilateral vocal cord paralysis（UVCP） with recurrent laryngeal nerve reinnervation through literature search, and to analyze the therapeutic effect of recurrent laryngeal nerve reinnervation on improving vocal function in UVCP. Methods:Electronic databases Pubmed, Web of Science, EMBASE, Cochrane Library, CNKI, and Wanfang databases were searched using relevant keywords and screened in strict accordance with the inclusion and exclusion criteria, and quality evaluations were conducted. Reported treatment outcomes were measured by relevant data extracted from literature, such as auditory perception assessment（GRBAS）, voice handicap index（VHI）, maximal phonation time（MPT）, jitter, shimmer, and noise harmonic ratio（NHR）, etc. Meta-analysis was performed by Revman5.3 and heterogeneity was analyzed using fixed effects or random effects models. Results:Eight articles were included in this study, all of which showed that the postoperative maximum phonation time of patients was significantly prolonged compared to preoperative, while the postoperative GRBAS score, Jitter, Shimmer, and NHR decreased compared to preoperative with statistical significance. Conclusion:The innervation of the internal laryngeal muscle was obtained through the reinnervation of the recurrent laryngeal nerve, which effectively improved the patient's vocal function and had a good long-term therapeutic effect. Although there was no difference in the efficacy of surgical methods for reconstructing the recurrent laryngeal nerve, the anastomosis between ansa cervicalis nerve and the recurrent laryngeal nerve is more ideal. Further randomized controlled studies with longer follow-up periods and larger samples will increase the credibility of their effectiveness.

Paediatric recurrent laryngeal nerve reinnervation at The Children’s Hospital at Westmead: a case series

Paediatric recurrent laryngeal nerve reinnervation at The Children’s Hospital at Westmead: a case series

Effectiveness of laryngeal reinnervation compared to medialization thyroplasty in the treatment of unilateral vocal fold paralysis: A systematic review and network meta‐analysis

Effectiveness of laryngeal reinnervation compared to medialization thyroplasty in the treatment of unilateral vocal fold paralysis: A systematic review and network meta‐analysis

Iatrogenic pediatric unilateral vocal cord paralysis after cardiac surgery: a review.

Unilateral vocal cord paralysis (UVCP) is a growing area of research in pediatrics as it spans across many specialties including otolaryngology, cardiology, general surgery, respirology, and speech language pathology. Iatrogenic injury is the most common cause of UVCP, however there is a wide range of data reporting the prevalence, symptom burden, and best treatment practice for this condition. The literature included systematic reviews and meta-analyses, retrospective studies and limited prospective studies. Overall, the literature lacked consistency in the diagnosis, treatment, and long-term outcomes of patients with UVCP. Many articles conflated bilateral vocal cord paralysis (BVCP) with UVCP and had limited data on the natural history of the condition. There was no consensus on objective and subjective measurements to evaluate the condition or best indications for requiring surgical intervention. Thyroplasty, injection medialization (IM) and recurrent laryngeal nerve reinnervation (RLNR) were the reported surgical interventions used to treat UVCP, however there was limited data on short and long-term surgical outcomes in children. More research is needed to determine the true prevalence, natural history, indications for surgical intervention and long-term outcomes for pediatric patients with this condition.

Laryngeal Reinnervation as a Treatment Option for Permanent Unilateral Vocal Fold Paralysis

Laryngeal Reinnervation as a Treatment Option for Permanent Unilateral Vocal Fold Paralysis

The role of primary non-selective laryngeal reinnervation in the treatment of invasive thyroid cancer

The role of primary non-selective laryngeal reinnervation in the treatment of invasive thyroid cancer

Stimulated Vocal Fold Immobility After Vagal Nerve Stimulator Placement: A Case Series.

Vagal nerve stimulator (VNS) implantation is a vital therapy for epilepsy refractory to other treatments; however, it is associated with a very high rate of voice changes. Relatively few of these patients are evaluated for vocal fold motion impairments. In this series, we evaluate 5 such patients with a novel phenotype of forced abduction with VNS stimulation. Retrospective case series. Five patients with a VNS implant who underwent operative direct or in-office rigid laryngoscopy and had vocal fold motion impairment associated with VNS activation are included. All 5 patients had vocal fold mobility with VNS off and a fixed with activation. All patients exhibited vocal fold abduction with VNS activation. Patient 2 has since undergone laryngeal reinnervation, which helped her intermittent dysphonia but left a small glottic gap. A type 1 thyroplasty corrected this gap and improved her voice further. Patient 3 has undergone laryngeal reinnervation for which early results show improvement in perceptual and patient reported outcomes. Patients 4 and 5 have both undergone laryngeal reinnervation with improvement in voice. Previous reported cases of stimulated immobility associated with VNS use describe only adduction of the vocal fold. This series expands the previous work showing the VNS activation can also cause stimulated immobility in an abducted position, for which reinnervation and other medialization procedures offer promising treatment.

Long-Term Outcomes of Pediatric Laryngeal Reinnervation.

Pediatric nonselective laryngeal reinnervation (NSLR) has gained popularity in recent years; however, long-term outcomes have not been reported. Patients greater than 1 year post reinnervation were recruited. Families were asked to report Pediatric Voice-Related Quality of Life (PVRQOL) and provide an audio recording of connected speech. PVRQOL and voice measures were compared with preoperative and early postoperative outcomes (<12 months) using analysis of variance (ANOVA) for repeated measures and post hoc tests for linear trend. Sixty-six patient families were contacted. Twelve patients responded with PVRQOL; six (50%) were female. Median age at surgery was 6.4 (range 1.9-15) and at follow-up 13.5 (range 10-18), with a median of 6.8 years (range 3-9.1) since surgery at follow-up. Mean preoperative PVRQOL was 68.1 (95% CI 52.3-84.0), early postoperative 86.5 (73.2-99.7), and long-term 90 (82.7-97.3). ANOVA showed no significant difference between values (p = 0.1228), but post hoc testing showed improving outcomes over time (p-for-trend 0.0304). PVRQOL was stable between early postoperative and long-term values (p = 0.3399). Four voice samples were adequate for analysis. Mean preoperative cepstral peak prominence (CPP) was 5.2 (95% CI 3.4-7.0), early postoperative 8.5 (5.5-11.5), and long-term 6.8 (2.77-10.89, p = 0.3340, p-for-trend 0.2988) Low-to-high spectral ratio was 22.3 preoperatively (14.0-30.5), 23.0 early postoperative (17.4-28.7), and 28.8 long-term (17.4-40.2, p = 0.1174, p-for-trend 0.0364). Cepstral spectral index of dysphonia (CSID) was 83.0 preoperatively (44.1-121.8), 39.4 early postoperative (20.4-58.3), and 45.53 long-term (-0.05-91.1, p = 0.4457, p-for-trend 0.1464). Years after NSLR, PVRQOL, low-to-high spectral ratio, and CSID show no evidence of degradation over time. 4 Laryngoscope, 2024.

Utility of laryngeal electromyography for establishing prognosis and individualized treatment after laryngeal neuropathies.

Laryngeal electromyography (LEMG) is a technique used to characterize neuropathic injuries to the recurrent laryngeal nerve (RLN) and superior laryngeal nerve (SLN). The RLN and SLN innervate the laryngeal muscles to produce vocal fold (VF) motion and elongation, respectively. VF motion deficiencies can affect voice, swallowing, and breathing, which can greatly affect a patient's quality of life. Neuropathy-related VF motion deficiencies most often result from surgical interventions to the skull base, neck, or chest likely due to the circuitous route of the RLN. LEMG is ideally conducted by an electromyographer and an otolaryngologist using a team-approach. LEMG is a powerful diagnostic tool to better characterize the extent of neuropathic injury and thus clarify the prognosis for VF motion recovery. This updated review discusses current techniques to improve the positive and negative predictive values of LEMG using laryngeal synkinesis and quantitative LEMG. Synkinesis can be diagnosed by comparing motor unit potential amplitude during vocalization and sniff maneuvers when recording within adductor muscles. Quantitative turns analysis can measure motor unit recruitment to avoid subjective descriptions of reduced depolarization during vocalization, and normal values are >400 turns/s. By integrating qualitative, quantitative, and synkinetic data, a robust prognosis can help clinicians determine if VF weakness will recover. Based on LEMG interpretation, patient-centered treatment can be developed to include watchful waiting, temporary VF augmentation, or definitive medialization procedures and laryngeal reinnervation.

양측 성대 마비의 치료

Laryngeal reinnervation has been investigated as a treatment option for bilateral vocal fold paralysis (BVFP) that can restore laryngeal function while preserving laryngeal anatomy. Traditionally, BVFP treatment involves irreversible structural changes to the larynx, such as tracheostomy, arytenoidectomy, or cordectomy, which often result in impaired voice and swallowing. In contrast, laryngeal reinnervation aims to restore laryngeal muscle tone and function by providing new neural input to the paralyzed larynx. Reinnervation techniques can be broadly categorized into non-selective and selective methods. Non-selective reinnervation, such as recurrent laryngeal nerve (RLN) end-to-end anastomosis or ansa cervicalis-to-RLN anastomosis, primarily focuses on maintaining muscle bulk and tone. Selective reinnervation techniques, including nerve-muscle pedicle with the ansa cervicalis, selective reinnervation using the phrenic nerve, and bilateral selective laryngeal reinnervation, aim to restore both abduction and adduction function of the larynx. This review summarizes the current laryngeal reinnervation techniques for BVFP treatment.

Management of Pediatric Bilateral Vocal Fold Paralysis: A State-of-the-Art Review of Etiologies, Diagnosis, and Treatments.

This paper reviews the current literature about epidemiology, etiologies, diagnosis, and management of pediatric bilateral vocal fold paralysis (PBVFP). According to PRISMA statements, a narrative review of the current literature was conducted through the PubMed, Scopus, and Cochrane Library databases about the epidemiology, etiologies, diagnosis, and management of PBVFP. PBVCP is the second most common congenital laryngeal anomaly in the pediatric population, accounting for 10% to 20% of pediatric laryngeal conditions. PBVCP is related to idiopathic (42.2%), congenital (19.7%), and neurological (16.9%) conditions. A tracheotomy is required in 60% of cases regarding stridor and dyspnea, which are the most prevalent symptoms. The diagnosis is based on the etiological features, clinical presentation, laryngoscopic findings, and objective examinations. Laryngeal electromyography may be used to support the diagnosis in difficult cases, but its reliability depends on the practitioner's experience. The primary differential diagnosis is posterior glottis stenosis, which needs to be excluded regarding therapeutic and management differences with PBVCP. Transient surgical procedures consist of tracheotomy or laterofixation of the vocal fold. Current permanent procedures include uni- or bilateral partial arytenoidectomy, posterior transverse cordotomy, cricoid splits, and laryngeal selective reinnervation. There is no evidence of the superiority of some procedures over others. PBVCP is the second most common laryngeal disorder in the pediatric population. Diagnosis is based on etiological and clinical findings and may require the use of laryngeal electromyography. Therapeutic management may involve several transient or permanent surgical procedures that are associated with overall subjective improvements in symptoms, laryngeal findings, and low complication rates.

Netrin-1 as A neural guidance protein in development and reinnervation of the larynx

Neural guidance proteins participate in motor neuron migration, axonal projection, and muscle fiber innervation during development. One of the guidance proteins that participates in axonal pathfinding is Netrin-1. Despite the well-known role of Netrin-1 in embryogenesis of central nervous tissue, it is still unclear how the expression of this guidance protein contributes to primary innervation of the periphery, as well as reinnervation. This is especially true in the larynx where Netrin-1 is upregulated within the intrinsic laryngeal muscles after nerve injury and where blocking of Netrin-1 alters the pattern of reinnervation of the intrinsic laryngeal muscles. Despite this consistent finding, it is unknown how Netrin-1 expression contributes to guidance of the axons towards the larynx. Improved knowledge of Netrin-1’s role in nerve regeneration and reinnervation post-injury in comparison to its role in primary innervation during embryological development, may provide insights in the search for therapeutics to treat nerve injury. This paper reviews the known functions of Netrin-1 during the formation of the central nervous system and during cranial nerve primary innervation. It also describes the role of Netrin-1 in the formation of the larynx and during recurrent laryngeal reinnervation following nerve injury in the adult.

An Independent C1 Nerve Root Variant of the Ansa Cervicalis: A Case Report

The ansa cervicalis (AC) is a neural loop within the carotid triangle of the anterior neck. The loop is traditionally formed by nerve roots C1–C3 of the cervical plexus and extends multiple motor branches. The current case was discovered during a routine dissection as an anatomical variation of the right AC in an 86-year-old Caucasian male cadaver. In this variation, the C1 nerve root did not form the typical loop with the C2 and C3 nerve roots, but instead, remained independent, traveling deep to the superior belly of the omohyoid muscle to supply the sternothyroid muscle. Because no loop was formed, the anatomy of the current case was not an ansa according to the Latin origin of the word, meaning handle or loop. The AC is an important anatomical landmark within the neck and is implicated in laryngeal reinnervation and respiratory nerve stimulation for patients with sleep apnea. The current anatomical variant contributes to a relatively limited catalog of identified anomalies. Knowledge of new AC variations can guide future surgical interventions and further develop the current base of knowledge surrounding the neuromuscular structures of the head and neck.

Long-Term Outcomes and Revision Rates in Laryngeal Reinnervation.

Nonselective laryngeal reinnervation is an effective procedure to improve voice quality after unilateral vocal fold paralysis. Few studies have captured long-term outcome data, and the revision rate for this operation is currently unknown. The objective of this study is to describe the long-term outcomes and revision rates of unilateral, nonselective reinnervation in pediatric and adult patients. Patients who underwent laryngeal reinnervation from 2000 to 2022 with a single surgeon were identified for inclusion. Patients who underwent bilateral, super selective, deinnervation and reinnervation, and/or concurrent arytenoid adduction procedures were excluded. Outcome measures included maximum phonation time [MPT], voice handicap index score [VHI], patient-reported percent normal voice, revision procedures, and complications. Data were compiled and analyzed using paired t-tests, repeated measures analysis of covariance, and binary logistic regression analysis. One hundred thirty-two patients underwent unilateral, nonselective ansa-recurrent laryngeal nerve [RLN] laryngeal reinnervation. Reinnervation significantly improved MPT and patient-reported percentage of normal voice and significantly decreased VHI. Eleven patients underwent revision procedures, corresponding to a revision rate of 8.3%. Additional procedures included medialization laryngoplasty [n = 3], medialization laryngoplastywith arytenoid adduction [n = 3] and injection augmentation greater than 1 year after reinnervation [n = 5]. The only factor associated with the need for additional surgery was time lapse from nerve injury to reinnervation. The overall complication rate was 6.8%; no patient required reintubation or tracheostomy. Unilateral, nonselective laryngeal reinnervation can provide reliable improvement in vocal symptoms after recurrent laryngeal nerve injury. The revision rate after laryngeal reinnervation is favorable and comparable to framework surgery. 4 Laryngoscope, 134:3187-3192, 2024.

Systematic review and meta-analysis of laryngeal reinnervation techniques in adults with unilateral and bilateral vocal fold palsies.

To evaluate the outcomes of reinnervation techniques for the treatment of adult unilateral vocal fold paralysis and bilateral vocal fold paralysis. A literature review was conducted in the Embase and Medline databases in English, with no limitations on the publication date. The outcome parameters of interest included visual, subjective perceptual, acoustic, aerodynamic analysis and electromyography. A meta-analysis with a random-effects model and inverse variance was calculated. The systematic Preferred Reporting Items for Systematic Reviews and Meta-Analyses approach resulted in 27 studies, totalling 803 patients (747 unilateral cases and 56 bilateral cases). Thyroid cancer and/or surgery had caused unilateral vocal fold paralysis in 74.8 per cent of cases and bilateral vocal fold paralysis in 69.6 per cent of cases. Statistically significant improvements in patients were observed for voice, deglutition and decannulation (bilateral vocal fold paralysis). Meta-analysis of 10 reinnervation techniques was calculated for the maximum phonation time of 184 patients. Reinnervation was shown to improve voice, swallowing and decannulation, but studies lacked control groups, limiting generalisability. Larger studies with controls are needed.

Contralateral laryngeal reinnervation in the patient with the right-sided vocal cord paralysis – case-report

Introduction: Paralysis of the nerves supplying the larynx leading to the vocal fold paralysis may have iatrogenic, proliferative, idiopathic or post-traumatic etiology. The most common etiology is iatrogenic, including a complication of the removal of paraganglioma tumors. One of the therapeutic options for vocal cord paralysis in the course of nerve damage is reinnervation of the larynx. One of the most frequently used reinnervation techniques is the anastomosis of the recurrent laryngeal nerve with the cervical ansa, usually ipsilateral or, less often, contralateral. Case presentation: The description concerns a 41-year-old patient with right-sided laryngeal paralysis after removal ofa paraganglioma of the parapharyngeal space, the area of the jugular foramen and the skull base who underwent laryngeal reinnervation using a contralateral cervical ansa. Conclusion: Laryngeal reinnervation procedure involving anastomosis of the recurrent laryngeal nerve with the contralateral cervical ansa allows recovery of the vocal fold function in a situation when the ipsilateral cervical ansa is damaged. This reinnervation involves taking a much longer section of the cervical ansa than in cases of ipsilateral reconstruction. Moreover this method requires creating a tunnel under the prelaryngeal muscles and passing the cervical ansa over the trachea or larynx.

Effect of Aging on Vocal Outcomes After Laryngeal Reinnervation Combined With Arytenoid Adduction

To evaluate the impact of aging on vocal function following laryngeal reinnervation combined with arytenoid adduction (AA) in the treatment of paralytic dysphonia. Sixty-eight patients with unilateral vocal fold paralysis who underwent refined nerve-muscle pedicle flap (NMP) implantation and AA were classified into four groups according to age: under 50 years (-50), in their 50s, 60s, and 70 years and older (70+). These groups consisted of 15, 14, 22, and 17 patients, respectively. Their vocal function was followed periodically for 24 months after surgery. Vocal function in all groups showed significant improvement after surgery. Significant improvements in vocal function were observed during a 24-month follow-up period: maximum phonation time in the -50 and 50seconds groups; pitch range and voice handicap index-10 in the -50, 50s, and 60s groups; "Grade" in the -50, 50s, and 70+groups; and "Breathiness" and voice-related quality of life in all groups. There were no significant differences in vocal function among the four groups, except for pitch range, at the 24-month postoperative assessment. Although the younger groups tended to exhibit better vocal function compared to the older groups 24 months postoperatively, the refined NMP+AA proved effective in the treatment of breathy dysphonia resulting from unilateral vocal fold paralysis, not only in the younger population but also in the older population.

What Is the Role of Laryngeal Reinnervation Surgery for Adults With Unilateral Vocal Fold Paralysis?

The LaryngoscopeEarly View Triological Society Best Practice What Is the Role of Laryngeal Reinnervation Surgery for Adults With Unilateral Vocal Fold Paralysis? Pranati Pillutla MD, Pranati Pillutla MD orcid.org/0000-0001-5765-2761 Department of Head and Neck Surgery, University of California Los Angeles, Los Angeles, California, USASearch for more papers by this authorKirsten Meenan MD, Kirsten Meenan MD Department of Head and Neck Surgery, University of California Los Angeles, Los Angeles, California, USASearch for more papers by this authorDinesh K. Chhetri MD, Corresponding Author Dinesh K. Chhetri MD [email protected] Department of Head and Neck Surgery, University of California Los Angeles, Los Angeles, California, USA Send correspondence to Dinesh K. Chhetri, Department of Head and Neck Surgery, 62-132 CHS, UCLA Medical Center, 10833 Le Conte Ave, Los Angeles, CA 90095, USA. Email: [email protected]Search for more papers by this author Pranati Pillutla MD, Pranati Pillutla MD orcid.org/0000-0001-5765-2761 Department of Head and Neck Surgery, University of California Los Angeles, Los Angeles, California, USASearch for more papers by this authorKirsten Meenan MD, Kirsten Meenan MD Department of Head and Neck Surgery, University of California Los Angeles, Los Angeles, California, USASearch for more papers by this authorDinesh K. Chhetri MD, Corresponding Author Dinesh K. Chhetri MD [email protected] Department of Head and Neck Surgery, University of California Los Angeles, Los Angeles, California, USA Send correspondence to Dinesh K. Chhetri, Department of Head and Neck Surgery, 62-132 CHS, UCLA Medical Center, 10833 Le Conte Ave, Los Angeles, CA 90095, USA. Email: [email protected]Search for more papers by this author First published: 09 February 2023 https://doi.org/10.1002/lary.30614 Editor's Note: This Manuscript was accepted for publication on January 25, 2023. The authors have no other funding, financial relationships, or conflicts of interest to disclose. Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Early ViewOnline Version of Record before inclusion in an issue RelatedInformation

성대 마비의 치료

Vocal fold paralysis can occur for various reasons, and vocal fold paralysis treatment is important to improve the quality of life and secure airway according to voice. There are several methods of unilateral and bilateral vocal fold paralysis; voice therapy, injection laryngoplasty, laryngeal framework surgery, reinnervation procedures, tracheostomy, arytenoidectomy, cordotomy, cordectomy, and laterofixation of vocal cord. This review paper aims to discuss the treatment principles of unilateral and bilateral vocal fold paralysis.

A New Animal Model of Laryngeal Transplantation.

Only three laryngeal transplants have been described in the literature to date, and none of the techniques has enabled a completely satisfactory functional result to be obtained. This article presents a new model of laryngeal transplantation, with quality of revascularisation of the transplant being the principal objective and optimisation of the various steps of the procedure, with the integration of a new reinnervation technique as a secondary objective. We present a preclinical animal study. Three pig larynges removed in vivo underwent allotransplantation according to the same protocol. The quality of the revascularisation was examined immediately after the surgery as well as by endoscopy for one animal on the fourth day after the operation. The mean time of cold ischaemia was 3 h 15 min. The anaesthetic tolerance of the pigs was excellent. Revascularisation was achieved and judged to be excellent for the three transplants immediately after the operation and the endoscopy performed for one pig on the fourth day after the operation confirmed this result. The anatomical similarities also enabled the application and integration of an innovative technique of laryngeal reinnervation into the various phases of the operation. We describe a reliable and reproducible animal model for laryngeal transplantation. Its application in humans can be envisaged.