[Efficacy of prevention of recurrent laryngeal nerve injury in thyroid surgery]. / Effektivnost' profilaktiki povrezhdenii vozvratnogo gortannogo nerva pri operatsiyakh na shchitovidnoi zheleze.

OBJECTIVE: To evaluate the effectiveness of prevention of recurrent laryngeal nerve injury depending on thyroid gland lesion and extent of surgery. MATERIAL AND METHODS: There were 2412 thyroid surgeries between 2000 and 2020. Patients were divided into the main group (1689 patients) and the control group (729 patients). Patients with nodular thyroid gland lesions prevailed in both groups (987 (58.4%) and 415 (56.9%), respectively). All ones underwent atraumatic extrafascial desection and thyroid resection (ultrasonic scalpel). RESULTS. T: He upper laryngeal nerve injury occurred in 35 cases (1.4%). The number of surgeries with thyroid remnant preservation was significantly lower in the main group. The number of procedures with subtotal thyroid resection and thyroidectomy increased by 2.4 times (from 414 to 1010 operations, p<0.05). CONCLUSION: Improvement of surgical treatment of thyroid gland lesions consisting in new operative technique of recurrent laryngeal nerve isolation using ultrasonic scalpel reduces the incidence of recurrent laryngeal nerve injury from 2.3% to 1%. At the same time, the number of extended procedures in the main group significantly exceeded that in the control group (by 2.5 times).

Multicentre randomized clinical trial on robot-assisted versus video-assisted thoracoscopic oesophagectomy (REVATE trial).

BACKGROUND: Surgery for oesophageal squamous cell carcinoma involves dissecting lymph nodes along the recurrent laryngeal nerve. This is technically challenging and injury to the recurrent laryngeal nerve may lead to vocal cord palsy, which increases the risk of pulmonary complications. The aim of this study was to compare the efficacy and safety of robot-assisted oesophagectomy (RAO) versus video-assisted thoracoscopic oesophagectomy (VAO) for dissection of lymph nodes along the left RLN. METHODS: Patients with oesophageal squamous cell carcinoma who were scheduled for minimally invasive McKeown oesophagectomy were allocated randomly to RAO or VAO, stratified by centre. The primary endpoint was the success rate of left recurrent laryngeal nerve lymph node dissection. Success was defined as the removal of at least one lymph node without causing nerve damage lasting longer than 6 months. Secondary endpoints were perioperative and oncological outcomes. RESULTS: From June 2018 to March 2022, 212 patients from 3 centres in Asia were randomized, and 203 were included in the analysis (RAO group 103; VAO group 100). Successful left recurrent laryngeal nerve lymph node dissection was achieved in 88.3% of the RAO group and 69% of the VAO group (P < 0.001). The rate of removal of at least one lymph node according to pathology was 94.2% for the RAO and 86% for the VAO group (P = 0.051). At 1 week after surgery, the RAO group had a lower incidence of left recurrent laryngeal nerve palsy than the VAO group (20.4 versus 34%; P = 0.029); permanent recurrent laryngeal nerve palsy rates at 6 months were 5.8 and 20% respectively (P = 0.003). More mediastinal lymph nodes were dissected in the RAO group (median 16 (i.q.r. 12-22) versus 14 (10-20); P = 0.035). Postoperative complication rates were comparable between the two groups and there were no in-hospital deaths. CONCLUSION: In patients with oesophageal squamous cell carcinoma, RAO leads to more successful left recurrent laryngeal nerve lymph node dissection than VAO, including a lower rate of short- and long-term recurrent laryngeal nerve injury. Registration number: NCT03713749 (http://www.clinicaltrials.gov).

Oesophageal cancer often requires complex surgery. Recently, minimally invasive techniques like robot- and video-assisted surgery have emerged to improve outcomes. This study compared robot- and video-assisted surgery for oesophageal cancer, focusing on removing lymph nodes near a critical nerve. Patients with a specific oesophageal cancer type were assigned randomly to robot- or video-assisted surgery at three Asian hospitals. Robot-assisted surgery had a higher success rate in removing lymph nodes near the important nerve without permanent damage. It also had shorter operating times, more lymph nodes removed, and faster drain removal after surgery. In summary, for oesophageal cancer surgery, the robotic approach may provide better lymph node removal and less nerve injury than video-assisted techniques.

The relation of recurrent laryngeal nerve to inferior thyroid artery and extralaryngeal nerve branching may increase the risk of vocal cord paralysis in thyroidectomy.

PURPOSE: The anatomical variations of the recurrent laryngeal nerve (RLN) are common during thyroidectomy. We aimed to evaluate the risk of RLN paralysis in case of its anatomical variations, retrospectively. METHODS: The patients with primary thyroidectomy between January 2016 and December 2019 were enrolled. The effect of age, gender, surgical intervention, neuromonitorisation type, central neck dissection, postoperative diagnosis, neck side, extralaryngeal branching, non-RLN, relation of RLN to inferior thyroid artery (ITA), grade of Zuckerkandl tubercle on vocal cord paralysis (VCP) were investigated. RESULTS: This study enrolled 1070 neck sides. The extralaryngeal branching rate was 35.5%. 45.9% of RLNs were anterior and 44.5% were posterior to the ITA, and 9.6% were crossing between the branches of the ITA. The rate of total VCP was 4.8% (transient:4.5%, permanent: 0.3%). The rates of total and transient VCP were significantly higher in extralaryngeal branching nerves compared to nonbranching nerves (6.8% vs. 3.6%, p = 0.018; 6.8% vs. 3.2%, p = 0.006, respectively). Total VCP rates were 7.2%, 2.5%, and 2.9% in case of the RLN crossing anterior, posterior and between the branches of ITA, respectively (p = 0.003). The difference was also significant regarding the transient VCP rates (p = 0.004). Anterior crossing pattern increased the total and transient VCP rates 2.8 and 2.9 times, respectively. CONCLUSION: RLN crossing ITA anteriorly and RLN branching are frequent anatomical variations increasing the risk of VCP in thyroidectomy that cannot be predicted preoperatively. This study is the first one reporting that the relationship between RLN and ITA increased the risk of VCP.

Intraoperative Adjuncts in Thyroid Surgery.

Thyroidectomy is relatively safe and often can be done as a minimally invasive procedure. Although they may be associated with a learning curve, thoughtful use of intraoperative adjuncts such as energy devices, recurrent laryngeal nerve monitoring, and parathyroid autofluorescence have the potential to make incremental improvements in the safety and efficiency of thyroid surgery. Perhaps many of these adjuncts may be of greatest benefit when used routinely by less experienced surgeons or selectively in higher-risk operations, although their adoption in practice continues to increase overall.

Double Recurrent Laryngeal Nerve with Thyroid Carcinoma.

The most important and serious complication of thyroid surgery is recurrent laryngeal nerve (RLN) injury, and it has been noted that this risk increases considerably in the presence of anatomical variations. Double recurrent laryngeal nerve (DRLN) is very rare among RLN anatomical variations. There are only a few case reports on DRLN in the literature It is crucial to possess surgical expertise and ensure complete visualization of the nerve to minimize the likelihood of RLN injury. Intraoperative nerve monitoring (IONM) is particularly useful in identifying anatomical variations. In a 54-year-old woman undergoing diagnostic left lobectomy+isthmectomy, a left DRLN was identified during intraoperative exploration and meticulous nerve exploration with the assistance of IONM monitoring verified that the impulse conduction in both branches was identical. The surgical procedure was successfully performed without causing any harm to the nerve. Based on the case reports in the literature and our experience with this patient, we believe that surgical expertise and the utilization of IONM can decrease RLN nerve damage and reveal its anatomical variations during thyroid surgery.

Transcriptome Analysis of Left Versus Right Intrinsic Laryngeal Muscles Associated with Innervation.

OBJECTIVES/HYPOTHESIS: Recurrent laryngeal nerve injury diagnosed as idiopathic or due to short-term surgery-related intubation exhibits a higher incidence of left-sided paralysis. While this is often attributed to nerve length, it is hypothesized there are asymmetric differences in the expression of genes related to neuromuscular function that may impact reinnervation and contribute to this laterality phenomenon. To test this hypothesis, this study analyzes the transcriptome profiles of the intrinsic laryngeal muscles (ILMs), comparing gene expression in the left versus right, with particular attention to genetic pathways associated with neuromuscular function. STUDY DESIGN: Laboratory experiment. METHODS: RNA was extracted from the left and right sides of the rat posterior cricoarytenoid (PCA), lateral thyroarytenoid (LTA), and medial thyroarytenoid (MTA), respectively. After high-throughput RNA-Sequencing, 88 samples were organized into 12 datasets according to their age (P15/adult), sex (male/female), and muscle type (PCA/LTA/MTA). A comprehensive bioinformatics analysis was conducted to compare the left-right ILMs across different conditions. RESULTS: A total of 774 differentially expressed genes were identified across the 12 experimental groups, revealing age, sex, and muscle-specific differences between the left versus right ILMs. Enrichment analysis of Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathways implicated several genes with a left-right laryngeal muscle asymmetry. These genes are associated with neuronal and muscular physiology, immune/inflammatory response, and hormone control. CONCLUSION: Bioinformatics analysis confirmed divergent transcriptome profiles between the left-right ILMs. This preliminary study identifies putative gene targets that will characterize ILM laterality. LEVEL OF EVIDENCE: N/A Laryngoscope, 134:3741-3753, 2024.

Outcomes of Immediate Total Thyroidectomy in First-Side Loss of Neuromonitoring Signal.

Importance: Use of intraoperative neuromonitoring (IONM) during thyroidectomy can nearly eliminate the risk of postoperative bilateral vocal cord palsy (VCP) by indicating staged surgery in cases of loss of signal (LOS) on the first side of planned total thyroidectomy. However, aborting planned total thyroidectomy may lead to persistence of symptoms, delay in adjuvant treatment, and patient inconvenience and distress. There are few data to guide a selective approach to total thyroidectomy in patients with first-side LOS. Objective: To investigate outcomes of immediate bilateral surgery in patients undergoing total thyroidectomy with first-side LOS. Design, Setting, and Participants: This cohort study was a retrospective review of outcomes for patients undergoing thyroidectomy between January 2016 and July 2023 at an academic tertiary referral center for thyroid surgery. Consecutive patients scheduled for total thyroidectomy using IONM were included. Exclusion criteria were preoperative VCP, deliberate sacrifice of recurrent laryngeal nerve (RLN), inadvertent RLN resection, and surgery performed without IONM. Exposures: Total thyroidectomy performed using IONM. Main Outcome Measures: Vocal mobility on first postoperative day as assessed by flexible laryngoscopy; secondary outcome measures included subjective voice assessment, other postoperative complications, and long-term vocal mobility. Results: Among 400 patients undergoing planned total thyroidectomy (mean age, 50.5 years [range, 4-88 years]; 318 female [79.5%]), 51 (12.8%) had first-side LOS, of whom 37 (9.3%) had persistent LOS. Twenty-nine patients (56% of procedures with first-side LOS, including 18 with persistent LOS) proceeded to immediate total thyroidectomy. Postoperatively, 16 patients (55% of patients undergoing total thyroidectomy following first-side LOS, including 14 of 18 with persistent LOS) had impaired vocal mobility. One patient had bilateral VCP that did not require tracheostomy, and 2 had postoperative hypoparathyroidism. Of those whose surgery was aborted after first-side LOS, 8 of 22 (36%) underwent completion thyroidectomy at a later stage. In those undergoing completion thyroidectomy, 2 of 8 (25%) had temporary VCP after the second surgery, 2 (25%) had permanent hypoparathyroidism, and 1 (12.5%) developed inoperable cancer. Postoperative VCP was fully reversible in all but 1 patient. Conclusion and Relevance: Among patients planned for total thyroidectomy who develop first-side LOS, immediate total thyroidectomy may be considered among those who have pressing reasons for same, and where surgical difficulties might be anticipated in a secondary surgery.

Impact of Intermittent Intraoperative Neuromonitoring (IONM) on the Learning Curve for Total Thyroidectomy by Residents in General Surgery.

INTRODUCTION: Recurrent laryngeal nerve (RNL) identification constitutes the standard in thyroidectomy. Intraoperative nerve monitoring (IONM) has been introduced as a complementary tool for RLN functionality evaluation. The aim of this study is to establish how routine use of IONM can affect the learning curve (LC) in thyroidectomy. METHODS: Patients undergoing total thyroidectomy performed by surgery residents in their learning curve course in 2 academic hospitals, were divided into 2 groups: Group A, including 150 thyroidectomies performed without IONM by 3 different residents, and Group B, including 150 procedures with routine use of intermittent IONM, by other 3 different residents. LC was measured by comparing operative time (OT), its stabilization during the development of the LC, perioperative complication rate. RESULTS: As previously demonstrated, the LC was achieved after 30 procedures, in both groups, with no differences due to the use of IONM. Similarly, there were no significant differences among the 2 groups, and between subgroups independently matched, for both OT and complications, even when comparing RLN palsy. Direct nerve visualization and IONM assessment rates were comparable in all groups, and no bilateral RLN palsy (transient or permanent) were reported. No case of interrupted procedure to unilateral lobectomy, due to evidence of RLN injury, was reported. CONCLUSIONS: The study demonstrates that the use of IONM thyroid surgery, despite requiring a specific training with experienced surgeons, does not particularly affect the learning curve of residents approaching this kind of surgery, and for this reason its routine use should be encouraged even for trainees.

The overtreatment of papillary thyroid microcarcinoma in the community.

INTRODUCTION: Total thyroidectomy is the traditional primary approach for papillary thyroid cancer. However, recent evidence supports conservative management for low-risk tumors like papillary thyroid microcarcinomas (PTMCs). This study explores the adoption of these practices in our community, using a cancer database to analyze treatment strategies. METHODS: A retrospective review of a 1433-patient institutional database identified 258 â€‹PTMC cases. Outcomes, including 30-day mortality, reoperation rate, postoperative hypocalcemia, and recurrent laryngeal nerve (RLN) injury, were assessed. RESULTS: Of PTMC patients, 63.4% underwent total thyroidectomy, with higher rates of RLN injury (8.8% vs. 2.3%) and hypocalcemia (12.4% vs. 0.0%) compared to lobectomy. Non-endocrine surgeons had higher postoperative radioactive iodine administration rates (28.6% vs. 6.1%). Subgroup analysis revealed a shift in total thyroidectomy rates based on tumor size and surgery period. CONCLUSION: Our community favors total thyroidectomy for PTMC, despite associated complications. Enhanced awareness and adherence to PTMC best practice guidelines are warranted.

Soft tissue injury events associated with neural integrity monitoring endotracheal tubes: A MAUDE database analysis.

OBJECTIVE: Neural integrity monitoring (NIM) endotracheal tubes are widely used to provide intraoperative monitoring of the recurrent laryngeal nerve during certain neck surgeries, especially thyroidectomy, in order to reduce the risk of nerve injury and subsequent vocal fold paralysis. The unique design of NIM tubes and the increased technical skill required for correct placement compared to standard endotracheal tubes may increase the risk of upper aerodigestive tract soft tissue injury. This study aims to describe adverse events related to NIM endotracheal tubes. STUDY DESIGN: Retrospective cross-sectional study. SETTING: The US Food and Drug Administration's MAUDE database (2010-2022); (Manufacturer and User Facility Device Experience). METHODS: The MAUDE database was queried for reports of adverse events that resulted in patient soft tissue injury involving the use of endotracheal tubes approved by the Food and Drug Administration. RESULTS: There were 28 reported soft tissue injuries, with all events being related to the NIM EMG family of endotracheal tubes manufactured by Medtronic Xomed, Inc. Overall, 24 were categorized as device-related adverse events, and 4 were unspecified in the event description. The most common soft tissue injuries were edema (n = 7) and perforation (n = 7), each accounting for 25 % of adverse events. The second most common injury type was laceration (n = 4), representing 14 % of all adverse events. Overall, 9 patients (32 %) in our cohort required a surgical intervention to treat their injuries, which consisted of 6 tracheotomies and 3 instances of suture repair. CONCLUSIONS: The most commonly reported types of soft tissue injury included edema and perforation, followed by laceration. Increased awareness of device-related patient injuries associated with NIM endotracheal tubes can be used to better inform surgeons and anesthesiologists during the process of intubation and surgical decision-making.

Long-Term Outcomes and Revision Rates in Laryngeal Reinnervation.

OBJECTIVES: 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. METHODS: 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. RESULTS: 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 laryngoplasty with 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. CONCLUSION: 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. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:3187-3192, 2024.

Fluorescence imaging to visualize the recurrent laryngeal nerve during thyroidectomy procedures: analysis of 65 cases and 81 nerves.

BACKGROUND: Recurrent laryngeal nerve (RLN) injury after thyroidectomy is relatively common. Locating the RLN prior to thyroid dissection is paramount to avoid injury. We developed a fluorescence imaging system that permits nerve autofluorescence. We aimed to determine the sensitivity and specificity of fluorescence imaging at detecting the RLN relative to thyroid and other background tissue and compared it to white light. METHODS: In this prospective study, 65 patients underwent thyroidectomy from January to April 2022 (16 bilateral thyroid resections) using white and fluorescent light. Fluorescence intensity [relative fluorescence units (RFU)] was recorded for RLN, thyroid, and background. RFU mean, minimum, and maximum values were calculated using Image J software. Thirty randomly selected pairs of white and fluorescent light images were independently reviewed by two examiners to compare RLN detection rate, number of branches, and length and minimum width of nerves visualized. Parametric and nonparametric statistical analysis was performed. RESULTS: All 81 RNLs observed were visualized more clearly under fluorescence (mean intensity, µ = 134.3 RFU) than either thyroid (µ = 33.7, p < 0.001) or background (µ = 14.4, p < 0.001). Forest plots revealed no overlap between RLN intensity and that of either other tissue. Sensitivity and specificity for RLN were 100%. All 30 RLNs and all 45 nerve branches were clearly visualized under fluorescence, versus 17 and 22, respectively, with white light (both p < 0.001). Visible nerve length was 2.5 × as great with fluorescence as with white light (µ = 1.90 vs. 0.76 cm, p < 0.001). CONCLUSIONS: In 65 patients and 81 nerves, RLN detection was markedly and consistently enhanced with autofluorescence neuro-imaging during thyroidectomy, with 100% sensitivity and specificity.

Early Changes in Porcine Larynges Following Injection of Motor-Endplate Expressing Muscle Cells for the Treatment of Unilateral Vocal Fold Paralysis.

OBJECTIVES: No curative injectable therapy exists for unilateral vocal fold paralysis. Herein, we explore the early implications of muscle-derived motor-endplate expressing cells (MEEs) for injectable vocal fold medialization after recurrent laryngeal nerve (RLN) injury. METHODS: Yucatan minipigs underwent right RLN transection (without repair) and muscle biopsies. Autologous muscle progenitor cells were isolated, cultured, differentiated, and induced to form MEEs. Three weeks after the injury, MEEs or saline were injected into the paralyzed right vocal fold. Outcomes including evoked laryngeal electromyography (LEMG), laryngeal adductor pressure, and acoustic vocalization data were analyzed up to 7 weeks post-injury. Harvested porcine larynges were examined for volume, gene expression, and histology. RESULTS: MEE injections were tolerated well, with all pigs demonstrating continued weight gain. Blinded analysis of videolaryngoscopy post-injection revealed infraglottic fullness, and no inflammatory changes. Four weeks after injection, LEMG revealed on average higher right distal RLN activity retention in MEE pigs. MEE-injected pigs on average had vocalization durations, frequencies, and intensities higher than saline pigs. Post-mortem, the MEE-injected larynges revealed statistically greater volume on quantitative 3D ultrasound, and statistically increased expression of neurotrophic factors (BDNF, NGF, NTF3, NTF4, NTN1) on quantitative PCR. CONCLUSIONS: Minimally invasive MEE injection appears to establish an early molecular and microenvironmental framework to encourage innate RLN regeneration. Longer follow-up is needed to determine if early findings will translate into functional contraction. LEVEL OF EVIDENCE: NA Laryngoscope, 134:272-282, 2024.

Clinical validation of NerveTrend versus conventional i-IONM mode of NIM Vital in prevention of recurrent laryngeal nerve events during bilateral thyroid surgery: A randomized controlled trial.

BACKGROUND: The aim of this study was to test the hypothesis that use of NerveTrend™ mode of intermittent neuromonitoring (i-IONM) during thyroidectomy may identify and prevent impending recurrent laryngeal nerve (RLN) injury. METHODS: A randomized clinical trial. The primary outcome was prevalence of RLN injury on postoperative day 1. In NerveTrend™ group the i-IONM stimulator was used for trending of amplitude and latency changes from initial vagal electromyographic baseline to tailor surgical strategy. RESULTS: Some 264 patients were randomized into the intervention versus the control group, 132 patients each. RLN injury was found on postoperative day 1 in 5/264 (1.89%) nerves at risk (NAR) versus 12/258 (4.65%) NAR whereas staged thyroidectomy was used in 0/132 (0.00%) versus 6/132 (4.54%) patients (p = 0.067 and p = 0.029, respectively). CONCLUSION: The use of NerveTrend™ mode resulted in tendency towards reduced RLN injury on postoperative day 1 and significant decrease of need for a staged thyroidectomy.

Changes in vocal fold gene expression and histology after injection augmentation in a recurrent laryngeal nerve injury model.

OBJECTIVE: To investigate changes in neuroregenerative pathways with vocal fold denervation in response to vocal fold augmentation. METHODS: Eighteen Yorkshire crossbreed swine underwent left recurrent laryngeal nerve transection, followed by observation or augmentation with carboxymethylcellulose or calcium hydroxyapatite at two weeks. Polymerase chain reaction expression of genes regulating muscle growth (MyoD1, MyoG and FoxO1) and atrophy (FBXO32) were analysed at 4 and 12 weeks post-injection. Thyroarytenoid neuromuscular junction density was quantified using immunohistochemistry. RESULTS: Denervated vocal folds demonstrated reduced expression of MyoD1, MyoG, FoxO1 and FBXO32, but overexpression after augmentation. Healthy vocal folds showed increased early and late MyoD1, MyoG, FoxO1 and FBXO32 expression in all animals. Neuromuscular junction density had a slower decline in augmented compared to untreated denervated vocal folds, and was significantly reduced in healthy vocal folds contralateral to augmentation. CONCLUSION: Injection augmentation may slow neuromuscular degeneration pathways in denervated vocal folds and reduce compensatory remodelling in contralateral healthy vocal folds.

Accelerometry May be Superior to EMG for Early Evaluation of Vocal Cord Function After Nerve Injury in a Pig Model.

OBJECTIVE: Vocal cord (VC) movement has been demonstrated by the use of accelerometry (ACC) to decrease in parallel with the electromyographic amplitude (EMG) during ongoing traction injury to the recurrent laryngeal nerve (RLN). When RLN function recovers, discrepancies between EMG and VC movement have been reported in clinical and experimental studies. The present study was conducted to clarify the actual relationship between EMG and VC movement measured by ACC during nerve recovery. METHODS: EMG obtained by continuous nerve monitoring (C-IONM) was compared with ACC during traction injury to the RLN, and throughout 40-min nerve recovery. A three-axis linear accelerometer probe was attached to the VC, and ACC data were registered as described. Traction damage was applied to the RLN until there was a 70% amplitude decrease from baseline EMG, or until loss of signal (LOS), that is, EMG values ≤100 µV. RESULTS: Thirty-two RLN from 16 immature pigs were studied. Correlation between EMG and ACC were calculated during nerve injury and nerve recovery. The mean correlations were for the 70% and LOS group from start to end of traction: 0.82 (±0.17) and 0.87 (±0.17), respectively. Corresponding correlation coefficients during 40-min recovery was 0.50 (±0.48) in the 70% group and 0.53 (±0.33) in the LOS group. CONCLUSION: There is a high correlation between EMG and VC movement during nerve injury, and a moderate correlation during early nerve recovery. EMG recovery after RLN injury ensures sufficient VC function as assessed by ACC. LEVEL OF EVIDENCE: N/A Laryngoscope, 134:1485-1491, 2024.

Refining postoperative monitoring of recurrent laryngeal nerve injury in esophagectomy patients through transcutaneous laryngeal ultrasonography.

BACKGROUND: Recurrent laryngeal nerve injury (RLNI) leading to vocal cord paralysis (VCP) is a significant complication following minimally invasive esophagectomy (MIE) with upper mediastinal lymphadenectomy. Transcutaneous laryngeal ultrasonography (TLUSG) has emerged as a non-invasive alternative to endoscopic examination for evaluating vocal cord function. Our study aimed to assess the diagnostic value of TLUSG in detecting RLNI by evaluating vocal cord movement after MIE. METHODS: This retrospective study examined 96 patients with esophageal cancer who underwent MIE between January 2021 and December 2022, using both TLUSG and endoscopy. RESULTS: VCP was observed in 36 out of 96 patients (37.5%). The incidence of RLNI was significantly higher on the left side than the right (29.2% vs. 5.2%, P < 0.001). Postoperative TLUSG showed a sensitivity and specificity of 88.5% (31/35) and 86.5% (45/52), respectively, with an AUC of 0.869 (P < 0.001, 95% CI 0.787-0.952). The percentage agreement between TLUSG and endoscopy in assessing VCP was 87.4% (κ = 0.743). CONCLUSIONS: TLUSG is a highly effective screening tool for VCP, given its high sensitivity and specificity. This can potentially eliminate the need for unnecessary endoscopies in about 80% of patients who have undergone MIE.

Recurrent laryngeal never monitoring versus non-monitoring in parathyroid surgery.

Background: Although intraoperative neural monitoring (IONM) is well established in thyroid surgery, it is less commonly analyzed in parathyroid operations. This study presents the results of IONM for primary and secondary hyperparathyroidism surgery. Methods: We retrospectively assessed 270 patients with primary hyperparathyroidism (PHPT), 53 patients with secondary hyperparathyroidism (SHPT), and 300 patients with thyroid cancer from June 2010 to June 2022 in one hospital in China. The follow-up was 12 months. Demographic, electromyography data from IONM, laboratory, and clinical information were collected. Laryngoscopy was collected from 109 patients with PHPT in whom IONM was not used. All groups were assessed by Pearson's chi-square test and Fisher's exact probability method to verify the relationship between parathyroid size and location, duration of surgery, preoperative concordant localization, laryngeal pain, IONM outcomes, cure rate, and RLN injury. Visual analog scale (VAS) assessed laryngeal pain. RLN outcomes were measured according to nerves at risk (NAR). Results: The study comprehended 918 NAR, that is 272, 105, 109, and 432 NAR for PHPT, SHPT with IONM, PHPT without IONM, and thyroid surgery control group, respectively. IONM successfully prevented RLN injury (P<0.001, P=0.012): Fifteen (5.51%) RLNs experienced altered nerve EMG profiles during surgery, and five (1.84%) experienced transient RLN injury in PHPT patients. Five (4.76%) RLNs were found to have altered EMG profiles during surgery, and one (0.95%) RLN had a transient RLN injury in SHPT patients. There was no permanent nerve injury (0.00%) in this series. There was no association between location, gland size, preoperative concordant localization, cure rate, duration of surgery, and IONM (P >0.05). Duration of surgery was associated with postoperative pharyngeal discomfort (P=0.026, P=0.024). Transient RLN injury was significantly lower in patients with PHPT who underwent IONM than in those who did not. Intraoperative neuromonitoring played an effective role in protecting the recurrent laryngeal nerve (P=0.035). Compared with parathyroidectomy, thyroidectomy had a higher rate of RLN injury (5.32%, P<0.001). Conclusion: IONM for SHPT and PHPT offers rapid anatomical gland identification and RLN functional results for effective RLN protection and reduced RLN damage rates.

Thyroid surgery in children and adolescents: results from a multi-institutional German and Austrian database.

BACKGROUND: Outcomes of paediatric thyroid surgery have only been reported in smaller series or over long intervals. The aim of this multicentre study was to describe the recent outcomes of paediatric thyroid surgery in Germany and Austria. METHODS: Patients aged less than or equal to 18 years who underwent thyroid surgery and were prospectively documented in the StuDoQ|Thyroid registry between March 2017 and August 2022 were studied. RESULTS: In total, 604 patients from 90 institutions were included. The mean age was 15.4 years and 75 per cent of patients were female. The most frequent benign pathologies were nodular goitre (35.6 per cent), follicular adenoma (30.1 per cent), and Graves' disease (28.5 per cent). Among 126 thyroid malignancies, papillary thyroid carcinoma was diagnosed in 77.8 per cent of patients, follicular thyroid carcinoma was diagnosed in 10.3 per cent of patients, and medullary thyroid carcinoma was diagnosed in 8.7 per cent of patients. Lymph node metastases were found in 45.9 per cent of patients with papillary thyroid carcinoma and in 36.4 per cent of patients with medullary thyroid carcinoma. Vascular invasion was found in 62.9 per cent of patients with follicular thyroid carcinoma. The mean tumour diameters were 18, 42, and 13 mm in patients with papillary thyroid carcinoma, follicular thyroid carcinoma, and medullary thyroid carcinoma respectively. Early postoperative recurrent laryngeal nerve injury was seen in 27 of 556 patients (4.9 per cent) (22 of 617 (3.6 per cent) nerves at risk with intermittent intraoperative nerve monitoring and 5 of 237 (2.1 per cent) nerves at risk with continuous intraoperative nerve monitoring). Persistent recurrent laryngeal nerve injury was documented in 4 of 556 patients (0.7 per cent). Early postoperative hypoparathyroidism correlated with Graves' disease, thyroid carcinoma, and lymph node dissection. CONCLUSION: Papillary thyroid carcinoma and follicular thyroid carcinoma in children were often advanced at presentation. Persistent or recurrent lymph node metastases were mainly seen in papillary thyroid carcinoma. Overall survival was excellent, but longer follow-up is needed.