Comparison of vocal outcome following two different procedures for immediate RLN reconstruction

Immediate Ansa cervicalis-to-recurrent laryngeal nerve low-tension anastomosis: A new technique for phonation recovery and bilateral anastomoses to avoid tracheotomy

OBJECTIVE

This case series study investigated the outcomes of an innovative approach, ansa cervicalis nerve (ACN)-to-recurrent laryngeal nerve (RLN) low-tension anastomosis.

METHODS

Patients who received laryngeal nerve anastomosis between May 2015 and September 2021 at the facility were enrolled. The inclusion criteria were patients with RLN dissection and anastomosis immediately during thyroid surgery. Exclusion criteria were cases with anastomosis other than cervical loop-RLN anastomosis or pronunciation recovery time > 6 months. Patients admitted before January 2020 were assigned to group A which underwent the conventional tension-free anastomosis, and patients admitted after January 2020 were group B and underwent the innovative low-tension anastomosis (Dong's method).

RESULTS

A total of 13 patients were included, 11 patients received unilateral surgery, and 2 underwent bilateral surgery. For patients who underwent unilateral anastomosis, group B had a significantly higher percentage of normal pronunciation via GRBAS scale (83.3 % vs. 0 %, p = 0.015) and voice handicap index (66.7 % vs. 0 %, p = 0.002), and shorter recovery time in pronunciation (median: 1-day vs. 4 months, p = 0.001) than those in group A after surgery.

CONCLUSIONS

ACNs-to-RLN low-tension anastomosis with a laryngeal segment ≤1 cm (Dong's method) significantly improves postoperative pronunciation and recovery time. The results provide clinicians with a new strategy for ACN -to-RLN anastomosis during thyroid surgery.

Modern Surgical Techniques of Thyroidectomy and Advances in the Prevention and Treatment of Perioperative Complications

Thyroid cancer is the most common cancer of the endocrine system, and, in recent years, there has been a phenomenon of overdiagnosis followed by subsequent overtreatment. This results in an increasing number of thyroidectomy complications being faced in clinical practice. In this paper, we present the current state of knowledge and the latest findings in the fields of modern surgical techniques, thermal ablation, the identification and assessment of parathyroid function, recurrent laryngeal nerve monitoring and treatment and perioperative bleeding. We reviewed 485 papers, from which we selected 125 papers that are the most relevant. The main merit of this article is its comprehensive view of the subject under discussion-both general, concerning the selection of the appropriate method of surgery, and particular, concerning the selection of the appropriate method of prevention or treatment of selected perioperative complications.

The Role of Primary Repair of the Recurrent Laryngeal Nerve during Thyroid/Parathyroid Surgery in Vocal Outcomes-A Systematic Review

Recurrent laryngeal nerve (RLN) injury is a well and long-known complication of thyroid and parathyroid surgery that significantly affects the quality of life of patients. Despite the advances in surgical techniques and technology, it still occurs in clinical practice either as temporary paresis or as permanent paralysis of the corresponding vocal cord. The purpose of the current systematic review is to examine the value of intraoperative repair of the RLN in voice restoration. A systematic review of the existing literature was conducted using PubMed, Scopus, Cochrane Library, and Google Scholar databases according to the PRISMA guidelines. The systematic review resulted in 18 studies, which met the inclusion criteria. An improvement in phonatory function and voice quality was observed in all these studies after immediate RLN reconstruction (not always statistically significant). This improvement appears to be comparable to or even higher than that achieved with other methods of repair, and in some cases, the improvement approaches levels found in normal subjects. Intraoperative RLN reconstruction is not widely used in clinical practice, but the evidence so far makes it a viable and safe alternative to traditional techniques with better long-term results, as it prevents the occurrence of atrophy of the vocal cord and should be considered in the operating room if possible.

Timing of Ansa Cervicalis-to-recurrent Laryngeal Nerve Reinnervation: A Systematic Review

BACKGROUND

Ansa cervicalis-to-recurrent laryngeal nerve anastomosis (ARA) is an established technique for the treatment of recurrent laryngeal nerve (RLN) injury after head and neck surgery. However, the optimal timing of ARA remains unclear, and the evidence bases for ARA performed at each timepoint after RLN injury have not previously been clearly distinguished. We conducted a systematic review of the literature to evaluate the efficacy of ARA performed at different timepoints on postoperative voice outcomes.

METHODS

A review of English-language journal articles published in the last 20 years was undertaken on three electronic databases: Ovid MEDLINE, PubMed and Embase. Studies with a focus on paediatric RLN injury, bilateral RLN injury, ansa cervicalis anatomy and non-ARA techniques alone were excluded.

RESULTS

Twenty eight articles were included in the review. ARA was performed as a delayed surgery in 16/28 studies (57%), while immediate ARA was utilized in 14/28 studies (50%). On qualitative synthesis, delayed ARA was shown to be effective in improving patient-reported, subjective observer-reported and objective observer-reported voice outcomes. Likewise, a substantial body of evidence was identified demonstrating postoperative voice improvement with immediate ARA. On direct comparison of timepoints, some benefit was shown for early delayed ARA relative to late delayed operations, while no comparative data for immediate versus delayed repair were available in the literature.

CONCLUSIONS

ARA at both delayed and immediate timepoints is effective in the treatment of patients with RLN injury after head and neck surgery. The timing of ARA may have some influence on its efficacy, with early delayed repair potentially associated with superior outcomes to late delayed operations, and immediate ARA offering several practical advantages relative to delayed repair. Further comparative studies are required to better characterize the optimal timing of ARA after RLN injury.

A novel method to reconstruct right recurrent laryngeal nerve by transforming into nonrecurrent laryngeal nerve: The end-to-free vagal laryngeal branch end anastomosis

The objective of this study is to demonstrate a novel method for the reconstruction of right recurrent laryngeal nerve (RLN) by transforming into nonrecurrent RLN: the end-to-free vagal laryngeal branch end anastomosis. Here we report a case of locally advanced thyroid carcinoma. The patient underwent radical thyroid surgery with inevitably partial RLN resection and immediate right RLN reconstruction at our institution. With the guidance of intraoperative neuromonitoring (IOMN), we completed a novel end-to-free vagal laryngeal branch end anastomosis. The whole procedure was deliberately monitored by IOMN. Surgeons can procure adequate free nerve for tension-free anastomosis by transforming the right RLN into nonrecurrent nerve. Follow-up laryngoscope showed improved adductory movement of the right arytenoid. The end-to-free vagal end anastomosis is an effective way to reconstruct segmental nerve resection of right RLN. Its long-term postoperative result needs to be further warranted.

Optimal Management of the Unilateral Recurrent Laryngeal Nerve Involvement in Patients with Thyroid Cancer

Simple Summary

Recurrent laryngeal nerve (RLN) is the second most common structure invaded by primary or metastatic thyroid cancer. However, little is known about the optimal procedure for maintaining vocal function in patients with unilateral RLN involvement in thyroid cancer. This study aimed to evaluate various parameters of vocal function to establish the optimal management of thyroid cancer patients with unilateral RLN involvement. Based on our findings, we propose that for optimal management of unilateral RLN involvement in thyroid cancer, first, sharp dissection should be performed, and if this is impossible, a simultaneous RLN reconstruction procedure should be adopted whenever possible. These findings may help improve management of RLN involvement in patients with thyroid cancer and ensure vocal function preservation.

Abstract

We aimed to determine the optimal management of recurrent laryngeal nerve (RLN) involvement in thyroid cancer. We enrolled 80 patients with unilateral RLN involvement in thyroid cancer between 2000 and 2016. Eleven patients with preoperatively functional vocal folds (VFs) underwent sharp tumor resection to preserve the RLN (shaving group). Thirty-three patients underwent RLN reconstruction with RLN resection (reconstruction group). We divided the reconstruction group into two subgroups based on preoperative VF mobility (normal-reconstruction and paralyzed-reconstruction subgroups). In the cases where RLN reconstruction was difficult, phonosurgeries including arytenoid adduction (AA), with or without thyroplasty type I, or nerve muscle pedicle implantation with AA were performed later (phonosurgery group). We evaluated and compared vocal function among the evaluated periods and different groups. Postoperative vocal function in the shaving and normal-reconstruction subgroups was favorable. There were no significant differences between the two groups. In the paralyzed-reconstruction and phonosurgery groups, postoperative vocal function was significantly improved, and vocal function in the paralyzed-reconstruction subgroup was significantly better than that in the phonosurgery group. For optimal management of unilateral RLN involvement in thyroid cancer, first, sharp dissection should be performed, and if this is impossible, a simultaneous RLN reconstruction procedure should be adopted whenever possible.

Immediate Intraoperative Repair of the Recurrent Laryngeal Nerve in Thyroid Surgery

OBJECTIVES

Recurrent laryngeal nerve (RLN) injury is a recognized risk during thyroid and parathyroid surgery and can result in significant morbidity. The aim of this review paper is to consider the optimal approach to the immediate intraoperative repair of the RLN during thyroid surgery.

METHODS

A PubMed literature search was performed from inception to June 2020 using the following search strategy: immediate repair or repair recurrent laryngeal nerve, repair or reinnervation recurrent laryngeal nerve and immediate neurorraphy or neurorraphy recurrent laryngeal nerve.

RESULTS

Methods of immediate intraoperative repair of the RLN include direct end-to-end anastomosis, free nerve graft anastomosis, ansa cervicalis to RLN anastomosis, vagus to RLN anastomosis, and primary interposition graft. Techniques of nerve repair include micro-suturing, use of fibrin glue, and nerve grafting. Direct micro-suture is preferable when the defect can be repaired without tension. Fibrin glue has also been proposed for nerve repair but has been criticized for its toxicity, excessive slow reabsorption, and the risk of inflammatory reaction in the peripheral tissues. When the proximal stump of the RLN cannot be used, grafting could be done using transverse cervical nerve, supraclavicular nerve, vagus nerve, or ansa cervicalis.

CONCLUSIONS

Current evidence is low-level; however, it suggests that when the RLN has been severed, avulsed, or sacrificed during thyroid surgery it should be repaired intraoperatively. The immediate repair has on balance more advantages than disadvantages and should be considered whenever possible. This should enable the maintenance of vocal cord tone, better and prompter voice recovery and avoidance of aspiration. Laryngoscope, 131:1429-1435, 2021.

Novel surgical methods for reconstruction of the recurrent laryngeal nerve: Microscope-guided partial layer resection and intralaryngeal reconstruction of the recurrent laryngeal nerve

BACKGROUND

The optimal strategy for surgical management of papillary thyroid carcinoma invasion of the recurrent laryngeal nerve remains controversial. Our aim was to evaluate the efficacy of 2 surgical methods and provide detailed descriptions of microscope-guided partial layer resection and intralaryngeal reconstruction of the recurrent laryngeal nerve.

METHODS

This retrospective study enrolled 85 patients with papillary thyroid carcinoma who underwent initial surgical excision for invasion of the recurrent laryngeal nerve. Twenty-seven patients (28 recurrent laryngeal nerve sites) underwent partial layer resection, and 11 patients (11 recurrent laryngeal nerve sites) underwent intralaryngeal reconstruction of the recurrent laryngeal nerve. The remaining patients underwent either only resection or resection with immediate reconstruction of the recurrent laryngeal nerve. Pre and postoperative phonetic function and rates of locoregional recurrence were extracted from medical charts for analysis.

RESULTS

Isolated locoregional recurrence specific to the aerodigestive tract was identified in 1 patient (3.7%) in the partial layer resection group and 1 patient (9.1%) in the intralaryngeal reconstruction group. Seventy-five percent of patients in the partial layer resection group recovered or had preserved vocal cord function, and the mean maximum phonation time of the patients with postoperative complete vocal cord palsy was 15.3 seconds. The mean maximum phonation time of the patients, excluding 4 patients with permanent stoma in the intralaryngeal reconstruction group, was 22.3 seconds. The mean maximum phonation time of either group was longer than that of patients with recurrent laryngeal nerve resection only and comparable with that of patients with recurrent laryngeal nerve resection and immediate reconstruction.

CONCLUSION

Patients who underwent either partial layer resection or intralaryngeal reconstruction had low rates of locoregional recurrence specific to the aerodigestive tract and good postoperative functional outcomes.

Guidelines for the Management of Unilateral Vocal Fold Paralysis From the Korean Society of Laryngology, Phoniatrics and Logopedics

The Korean Society of Laryngology, Phoniatrics and Logopedics appointed a task force to establish clinical practice guidelines for the management of unilateral vocal fold paralysis (UVFP). These guidelines cover a comprehensive range of management-related factors, including the diagnosis and treatment of UVFP, and provide in-depth information based on current, up-to-date knowledge. Detailed evidence profiles are provided for each recommendation. The CORE databases, including OVID Medline, Embase, the Cochrane Library, and KoreaMed, were searched to identify all relevant papers, using a predefined search strategy. When insufficient evidence existed, expert opinions and Delphi questionnaires were used to fill the evidence gap. The committee developed 16 evidence-based recommendations in six categories: initial evaluation (R1–4), spontaneous recovery (R5), medical treatment (R6), surgical treatment (R7–14), voice therapy (R15), and aspiration prevention (R16). The goal of these guidelines is to assist general otolaryngologists and speech-language pathologists who are primarily responsible for treating patients with UVFP. These guidelines are also intended to facilitate understanding of the condition among other health-care providers, including primary care physicians, nurses, and policy-makers.

Selective vagus-recurrent laryngeal nerve anastomosis in thyroidectomy with cancer invasion or iatrogenic transection

PURPOSE

Immediate recurrent laryngeal nerve (RLN) reconstruction at the time of thyroid cancer extirpation can provide excellent postoperative phonatory function. This study is to present our experience with the methods of RLN reconstruction, and to evaluate the role of selective vagus to RLN anastomosis (SVR) in thyroidectomy.

METHODS

Respective review of RLN reconstruction in thyroid surgery from January 2004 to October 2018 was conducted in two tertiary referral academic medical centers. Immediate RLN reconstruction was performed for primary thyroidectomy patients with intraoperative nerve tumor invasion or iatrogenic transection. Laryngofiberoscopic examination, voice evaluation of maximum phonation time, and GRBAS scale were performed preoperatively, on the second day after surgery, and monthly postoperatively for the first year.

RESULTS

A total of 37 patients were enrolled. Twenty-nine RLNs were resected caused by tumor-associated trauma; the other nerves were inadvertently transected. Direct anastomosis (DA) was performed in eight patients, free nerve graft (FNG) was performed in four patients, ansa cervicalis to RLN anastomosis (ARA) was performed in eight patients, and SVR was performed in 17 patients. The mean periods from the reinnervation surgery of DA, SVR, ARA, and FNG to the phonation recovery were 46 ± 19 (days), 41 ± 29 (days), 83 ± 21 (days), and 137 ± 32 (days), respectively. There were improvements in the GRBAS scale of perceptual voice quality at 1 month for DA and SVR, 2months for ARA.

CONCLUSIONS

Intraoperative SVR reinnervation demonstrated voice improvement postoperatively and might be an effective treatment for thyroidectomy-related permanent unilateral vocal cord paralysis.

Immediate Ansa Cervicalis-to-Recurrent Laryngeal Nerve Anastomosis for the Management of Recurrent Laryngeal Nerve Infiltration by a Differentiated Thyroid Carcinoma

OBJECTIVES

The optimal surgical approach to treat recurrent laryngeal nerve (RLN) infiltration by differentiated thyroid cancer (DTC) remains a subject of debate. This study explored the feasibility and efficiency of immediate ansa cervicalis nerve (ACN)-to-RLN anastomosis for the management of RLN infiltration by DTC.

MATERIAL AND METHODS

Fifty-three patients who underwent immediate ACN-to-RLN anastomosis during DTC extirpation were enrolled in the present study. Thirty-seven cases presented with unilateral vocal cord paralysis before the operation (Group A), and another 16 patients presented with normal vocal cord mobility preoperatively (Group B). Multidimensional assessments, videostroboscopy, voice assessment, and laryngeal electromyography (LEMG) were performed preoperatively and postoperatively.

RESULTS

All videostroboscopy, voice assessment and LEMG parameters in Group A deteriorated 1 month after the operation and improved 1 year after the operation compared with preoperative data. In Group B, all parameters 1 year after the operation improved significantly compared with the corresponding parameters 1 month after the operation. LEMG in Group A and B provided substantial evidence for the maturation of neural regeneration from ACN and demonstrated that the laryngeal muscles were reinnervated successfully by this procedure.

CONCLUSIONS

If the RLN is infiltrated by DTC, immediate ACN-to-RLN anastomosis during complete excision of DTC could restore satisfactory phonatory function and does not compromise oncological radicality.

Recovery of Voice After Reconstruction of the Recurrent Laryngeal Nerve and Adjuvant Nimodipine

Background

Transection injury to the recurrent laryngeal nerve (RLN) has been associated with permanent vocal fold palsy, and treatment has been limited to voice therapy or local treatment of vocal folds. Microsurgical repair has been reported to induce a better function. The calcium channel antagonist nimodipine improves functional recovery after experimental nerve injury and also after cranial nerve injury in patients. This study aims to present voice outcome in patients who underwent repair of the RLN and received nimodipine during regeneration.

Methods

From 2002–2016, 19 patients were admitted to our center with complete unilateral injury to the RLN and underwent microsurgical repair of the RLN. After nerve repair, patients received nimodipine for 2–3 months. Laryngoscopy was performed repeatedly up to 14 months postoperatively. The Voice Handicap Index (VHI) was administered, and patients’ maximum phonation time (MPT) was recorded during the follow-up.

Results

All patients recovered well after surgery, and nimodipine was well tolerated with no dropouts. None of the patients suffered from atrophy of the vocal fold, and some patients even showed a small ab/adduction of the vocal fold on the repaired side with laryngoscopy. During long-term follow-up (>3 years), VHI and MPT normalized, indicating a nearly complete recovery from unilateral RLN injury.

Conclusions

In this cohort study, we report the results of the first 19 consecutive cases at our center subjected to reconstruction of the RLN and adjuvant nimodipine treatment. The outcome of the current strategy is encouraging and should be considered after iatrogenic RLN transection injuries.