Recurrent Nerve Research Articles

Various methods for intraoperative neural monitoring during thyroid surgery

Intraoperative neural monitoring (IONM) during thyroidectomy is an essential technique to safeguard the recurrent laryngeal nerve (RLN) and the external branch of the superior laryngeal nerve (EBSLN), both critical for vocal cord function. Utilizing electromyography (EMG), IONM provides real-time feedback on nerve integrity, significantly reducing the risk of nerve damage during surgery. The primary methods of IONM include endotracheal tube electrodes, surface electrodes, needle electrodes, and continuous monitoring, each with distinct advantages and limitations. Endotracheal tube electrodes offer direct measurements but can be difficult to position, while surface electrodes are non-invasive but may experience signal interference. Needle electrodes provide precise measurements but are invasive, and continuous monitoring offers ongoing feedback but requires advanced equipment. The evolution of IONM began in the mid-20th century and has progressed significantly, leading to its widespread adoption in thyroid surgery by the mid-2000s. Enhanced by recent technological advancements and standardized by professional guidelines, IONM has become integral in reducing postoperative complications. Ongoing research aims to further refine IONM techniques, ensuring optimal patient outcomes and the preservation of nerve function in thyroid surgery.

양측성 성대 마비의 수술적 치료

Bilateral vocal fold paralysis (BVFP) is characterized by the complete or partial inability to move the vocal folds. BVFP presents with inspiratory dyspnea resulting from airway narrowing at the glottic level, where both vocal folds are positioned paramedian. Historically, iatrogenic damage to the recurrent laryngeal nerves has been identified as a common cause of BVFP. This condition is often critical, necessitating immediate treatment such as intubation for short-term relief, and potentially surgical procedures like tracheostomy to address the compromised airway. The primary objective in managing BVFP is to alleviate dyspnea in affected patients. Treatment options include tracheostomy, arytenoidectomy, laterofixation, and cordotomy, each with varying degrees of effectiveness in improving airway function, though voice quality may be negatively impacted or remain unchanged. The diversity in study methodologies, the absence of large-scale controlled randomized trials, and the challenge of distinguishing BVFP from posterior glottic stenosis hinder the ability to definitively determine the superiority of one treatment approach over another.

Comparison between Zone 2 and Zone 3 distal anastomoses for aortic arch replacement in terms of invasiveness.

Zone 2 anastomosis with total cervical branch reconstruction for acute type A aortic dissection and aortic arch aneurysms became possible after stent-graft introduction. This may be an easier procedure and reduce the risk of recurrent laryngeal nerve palsy. Therefore, this study aimed to compare the outcomes between Zone 2 and Zone 3 distal anastomoses. After evaluating the patient data in our institute between April 2016 and April 2022, the patients in whom distal anastomosis was performed at Zone 2 with a stent-graft were defined as the Zone 2 group (n = 70). The patients in whom distal anastomosis was performed at Zone 3 were defined as the Zone 3 group (n = 24). The incidence of new-onset recurrent nerve palsy was one patient (1.4%) in the Zone 2 group and six patients (25.0%) in the Zone 3 group (p < 0.001). The lower body perfusion arrest time was 44.3 ± 9.1min in the Zone 2 group and 52.9 ± 12.8min in the Zone 3 group (p = 0.005). There were no significant differences in in-hospital mortality and morbidities. Multivariable analysis showed that only age was an independent predictor of overall mortality. Performing distal anastomosis at Zone 2 with a frozen elephant trunk or stent-graft reduced the lower body perfusion arrest time and possibly prevented recurrent nerve palsy.

Bilateral Trifurcation of the Recurrent Laryngeal Nerve: A Case Report

Introduction: Thyroidectomy is a common surgical procedure performed for a variety of thyroid disorders. NLR injury is a dreaded complication during thyroidectomy and is considered a challenge even by the most experienced surgeons. Case Report: A thirty-two-year-old female patient with no significant pathological history was admitted for management GMNH. Cervical ultrasonography revealed a multiheteronodular goitre classified as TIRADS 4, the largest nodule measuring four centimetres on the left, with no cervical adenopathy. Thyroid workup was normal. Thyroid cytology of nodule number 1 was consistent with follicular neoplasm (Bethesda stage four). A total thyroidectomy was performed, and a bilateral trifurcation of the two recurrent laryngeal nerves in the tracheoesophageal groove was found. Conclusion: Damage to the NLR is the most serious complication of thyroid surgery. Anatomical variations in the NLR increase the risk of iatrogenic nerve damage. Bilateral trifurcation of the recurrent laryngeal nerve is a relatively rare anatomical variation that should not be overlooked when locating this nerve for surgery.

Impact of Indocyanine Green Angiography on Postoperative Parathyroid Function: A Propensity Score Matching Study.

Background: Thyroidectomy constitutes an important portion of endocrine surgery procedures and is associated with various complications such as bleeding, recurrent laryngeal nerve injury, and postoperative hypoparathyroidsm. Effective parathyroid preservation during thyroid surgery is crucial for patient well-being, with current strategies heavily reliant on surgeon experience. Among various methods, Indocyanine Green Angiography (ICGA) offers a promising method for intraoperative assessment of parathyroid gland perfusion. Methods: In a retrospective study, patients undergoing bilateral thyroidectomy from January 2021 to January 2023 were analyzed, excluding those with previous thyroidectomy, parathyroid disease, or chronic kidney disease. The study compared a control group (n = 175) with an ICGA group (n = 120), using propensity score matching for statistical analysis. Matched cohorts included 120 patients in each group. The primary outcome of this study was identified as temporary postoperative hypoparathyroidism, with secondary outcomes including the rate of parathyroid reimplantation and the incidence of permanent postoperative hypoparathyroidism. Results: The ICGA group showed significantly more parathyroid autotransplantations (p < 0.01). While not statistically significant, the control group had a higher incidence of temporary postoperative hypoparathyroidism (p < 0.09). Rates of hypocalcemia on postoperative day 1 and permanent hypocalcemia were similar. Subgroup analysis indicated more postoperative day 1 hypoparathyroidism in the control group during central neck dissections (p < 0.049). Conclusions: Intraoperative ICGA use correlated with higher parathyroid autotransplantation and suggested reduced postoperative hypoparathyroidism. Changes in fluorescence intensity following a second ICG injection may provide an objective method to assess parathyroid perfusion. Further large-scale studies are needed to fully understand ICGA's impact on parathyroid preservation.

Subtotal esophagectomy and concurrent reconstruction with free jejunal flap for primary esophageal cancer after pancreatoduodenectomy.

Pancreatoduodenectomy and subtotal esophagectomy are widely considered the most invasive and difficult surgical procedures in gastrointestinal surgery. Subtotal esophagectomy after pancreatoduodenectomy is expected to be extremely difficult due to complicated anatomical changes, and selecting an appropriate intestinal reconstruction method will also be a difficult task. Therefore, perhaps because the method is considered impossible, there have been few reports of subtotal esophagectomy after pancreatoduodenectomy. A 73-year-old man with a history of pancreatoduodenectomy was diagnosed with superficial thoracic esophageal squamous cell carcinoma. Definitive chemoradiation therapy was recommended at another hospital; however, he visited our department to undergo surgery. We performed the robot-assisted thoracoscopic subtotal esophagectomy. There were some difficulties with the reconstruction: the gastric tube could not be used, the reconstruction was long, and the organs reconstructed in the previous surgery had to be preserved. However, the concurrent reconstruction was achieved with the help of a free jejunal flap and vascular reconstruction. All reconstructions from the previous surgery, including the remnant stomach, were preserved via regional abdominal lymph node dissection. After reconstruction, intravenous indocyanine green showed that circulation in the reconstructed intestines was preserved. On postoperative day 1, no recurrent nerve paralysis was observed during laryngoscopy. The patient could start oral intake smoothly 2weeks after surgery and did not exhibit any postoperative complications related to the reconstruction. The patient was transferred to another hospital on postoperative day 21. Owing to the free jejunal flap interposition method, we safely performed one stage subtotal esophagectomy and concurrent reconstruction, preservation of the remnant stomach, and pancreaticobiliary reconstruction in patients with a history of pancreatoduodenectomy. We believe that this method is acceptable and useful for patients undergoing complicated reconstruction.

Impact of thyroid carcinoma invasion of recurrent laryngeal nerve on cervical lymph node metastasis.

Papillary thyroid carcinoma (PTC) has a favorable prognosis. However, involvement of the recurrent laryngeal nerve (RLN) significantly increases the risk of recurrence. RLN invasion was an important factor in determining the extent of thyroid surgery. The purpose of this study was to compare clinicopathologic features and characterize risk factors of central and lateral lymph node metastasis (LLNM) of RLN invasion in patients with PTC. A retrospective review was conducted of 130 patients with PTCs who had exclusive tumor involvement of the RLN at our institution between January 2014 and February 2019. All patients underwent total thyroidectomy and high-dose radioactive iodine (RAI) therapy. The clinicopathologic factors and prognostic outcomes of the patients with solitary and multiple RLN involvements were compared. Kaplan-Meier method was performed to compare the outcomes of tumor recurrence. Univariate and multivariate logistic regression analyses were used to identify risk factors associated with LLNM. The invasion of the RLN was similar on both sides, with 58.5% on the right, 40.0% on the left, and 1.5% on both sides. Significant differences were observed in tumor size (p < 0.001), lymph node metastasis classification (p = 0.002), RLN resection (p < 0.001), and thyroglobulin (p = 0.010) in the solitary and multiple groups. During the median follow-up of 67 months, 9 (6.9%) patients developed recurrence. There were no statistical differences in recurrence for age, tumor size, gender, multifocality, lymph node metastasis (LNM), and RLN resection. According to receiver operating characteristic (ROC) curve analyses, a cut-off of tumor size > 1.7 cm was identified as the most sensitive and specific predictor of RLN with multiple involvements or LNM invasion. Univariate and multivariate analyses revealed that central lymph node metastasis (CLNM) and RLN invasion by LNM can serve as independent risk factors for LLNM (p = 0.006 and p < 0.001, respectively). Our results indicate that recurrence was comparable in patients with solitary and multiple RLN involvements. Multiple RLN involvement was associated with pathological features such as larger tumors, RLN resection, and LLNM. The presence of LNM invading RLN and multiple nerve involvement increases the risk of intraoperative RLN resection. A higher risk of multiple invasion or LNM invasion should be considered when tumor size > 1.7 cm. The presence of CLNM and RLN invaded by LNM were independent predictors for LLNM, which could aid surgeons in deciding on lateral lymph node dissection.

Léčba presbyfonie augmentací hlasivek autologním tukem – kazuistika

Summary Lipoinjection of vocal cords is a minimally invasive phonosurgical treatment, which is used to increase the volume of vocal cords if the glottal gap is less than 3 mm. Glottic gap is usually caused by paresis of the recurrent laryngeal nerve or as a result of vocal cord muscle atrophy in the elderly (presbyphonia). In this article, a case report of a patient with presbyphonia who underwent lipoinjection of the vocal cords is presented. The aim of this case report is to highlight the use of lipoinjetion of vocal cords in elderly patients with presbyphonia in case of unsuccessful conservative treatment. Key words glottal gap – augmentation of vocal cords – presbyphonia

Three-dimensional Computed Tomography Features of Recurrent Laryngeal Nerve Paralysis Due to Aortic Aneurysm

Three-dimensional Computed Tomography Features of Recurrent Laryngeal Nerve Paralysis Due to Aortic Aneurysm

STELLATE GANGLION BLOCK: CLINICAL MONITORING AFTER INJECTION

Abstract 70–year–old man with chronic coronaric syndrome (CABG x 6 in 2006) and HFrEF. ICD implant in primary prevention in 2011. He was admitted for arrhythmic storms refractory to IV lidocaine therapy. Following sedation with midazolam, a left stellate ganglion block was performed using the ultrasound–guided lateral approach, injecting 200 mg of Lidocaine and 200 mg of Mepivacaine. After a few minutes, there was the appearance of anisocoria, different thermotouch in the upper limbs, ptosis, dysphonia, as an effect of local anesthetics on the sympathetic nervous system fibers and on the recurrent laryngeal nerve, near the stellate ganglion. At the same time, the arrhythmias did not recur. Among the rare complications described in the literature (usually transient) arising after stellate ganglion block for the treatment of various chronic pain syndromes or refractory ventricular arrhythmias, we find: hoarseness, stridor, confusion, cough, severe hypertension, subdural/intrathecal block with respiratory arrest, loss of consciousness and paralysis of the four limbs, epileptic seizures, transient locked–in syndrome, headache, visual hallucinations, myoclonus, Horner‘s syndrome, diaphragmatic palsy (phrenic nerve injury), allergic reactions, bleeding and hematoma formation, dural puncture, pneumothorax, local infections. Serious adverse effects described include cases of death or tetraplegia following epidural abscess. For this reason, it is of utmost importance monitoring after the procedure and the availability of the equipment necessary for a possible resuscitation to avoid long–term of sequelae. Conclusion In cases of arrhythmic storm refractory to antiarrhythmic therapy, percutaneous stellate ganglion block is an effective and safe procedure and serious complications are rare.

Technical feasibility and oncological outcomes of robotic esophagectomy compared with conventional thoracoscopic esophagectomy for clinical T3 or T4 locally advanced esophageal cancer: a propensity-matched analysis.

Minimally invasive esophagectomy is the first-line approach for esophageal cancer; however, there has recently been a paradigm shift toward robotic esophagectomy (RE). We investigated the clinical outcomes of patients who underwent RE compared with those of patients who underwent conventional minimally invasive thoracoscopic esophagectomy (TE) for locally advanced cT3 or cT4 esophageal cancer using a propensity-matched analysis. Overall, 342 patients with locally advanced cT3 or cT4 esophageal cancer underwent transthoracic esophagectomy with total mediastinal lymph node dissection between 2018 and 2022. The propensity-matched analysis was performed to assign the patients to either RE or TE by covariates of histological type, tumor location, and clinical N factor. Overall, 87 patients were recruited in each of the RE and TE groups according to the propensity-matched analysis. The total complication rate and the rates of the three major complications (recurrent laryngeal nerve paralysis, anastomotic leakage, and pneumonia) were not significantly different between the RE and TE groups. However, the peak C-reactive protein concentration on postoperative day 3, rate of surgical site infection, and intensive care unit length of stay after surgery were significantly shorter in the RE group than in the TE group. No significant differences were observed in the harvested total and mediastinal lymph nodes. The total operation time was significantly longer in the RE group, while the thoracic operation time was shorter in the RE group than in the TE group. There was no significant difference between the two groups in the recurrence rate of oncological outcomes after surgery. RE may facilitate early recovery after esophagectomy with total mediastinal lymph node dissection and has the same technical feasibility and oncological outcomes as TE.

Minimally-Invasive Robotic-Assisted Resection for Intrathoracic Goiter – A Feasible Alternative to Thoracotomy and Sternotomy

Abstract Background Goiter is a common presentation in daily clinical practice. It usually grows slowly and in rare cases with intrathoracic extension. There is no clear definition of intrathoracic goiters. The incidence in the literature varies from 3% to 7%. Most intrathoracic goiters are localized in the anterior mediastinum, with less than 25% are localized in the posterior mediastinum. This presents a challenge for surgical resection. Traditionally, the intrathoracic portions have been resected via sternotomy for anterior goiters and thoracotomy for posterior goiters. With the increasing use of robotic surgery, new possibilities for minimally invasive surgery and especially robotic procedures have emerged. This may reduce morbidity and length of hospital stay. Aims The study aims to show that minimal-invasive, robotic-assisted resection for intrathoracic goiter is safe and feasible. Methods During the study period from January 2021 to December 2023, 548 thyroid operations were performed in our clinic. All operations were prospectively recorded in the Eurocrine registry and retrospectively analyzed. Goiter was defined as intrathoracic according to perioperative findings (caudal border not visible on sonography and/ or further preoperative investigations ordered). Primary and secondary endpoints were outcome, conversion rate, and incidence of intrathoracic goiter. Results In our clinic, 19/548 patients (3.5%) presented with intrathoracic goiter. 17/19 patients were operated via conventional cervical approach. In 2 patients, minimal-invasive robotic mobilization of the large posterior portion of the goiter was performed in combination with conventional cervical thyroidectomy. No conversion was required. Based on our cases, we present robotic intrathoracic thyroid mobilization as a novel technique to avoid thoracotomy. The rate of recurrent nerve palsy in intrathoracic goiter was 1/28 (3.5%) nerves at risk and occurred with conventional approach. No secondary bleeding or other complications were observed. Conclusion The minimal-invasive robotic approach seems to be a promising alternative to open procedures such as thoracotomy and can reduce morbidity and length of hospital stay.

Significance of atherosclerotic plaque location in recanalizing non-acute long-segment occlusion of the internal carotid artery

To investigate the significance of atherosclerotic plaque location in hybrid surgery comprising both endovascular recanalization approaches and carotid endarterectomy for symptomatic atherosclerotic non-acute long-segment occlusion of the internal carotid artery (ICA), 162 patients were enrolled, including 120 (74.1%) patients in the proximal plaque group and 42 (25.9%) in the distal plaque group. Surgical recanalization was performed in all patients, with successful recanalization in 119 (99.2%) patients in the proximal and 39 (92.9%) in the distal plaque group. The total successful recanalization rate was 97.5% (158/162) with a failure rate of 2.5% (4/162). Periprocedural complications occurred in 5 (4.2% or 5/120) patients in the proximal plaque group, including neck infection in two (1.7%), recurrent nerve injury in 1 (0.8%), and laryngeal edema in 2 (1.7%), and 2 (4.8%) in the distal plaque group, including femoral puncture infection in 2 (4.8%). No severe complications occurred in either group. Univariate analysis showed plaque location was a significant (P = 0.018) risk factor for successful recanalization, and multivariate analysis indicated that the plaque location remained a significant independent risk factor for recanalization success (P = 0.017). In follow-up 6–48 months after the recanalization surgery, reocclusion occurred in two (2.8%) patients in the proximal plaque group and 4 (13.3%) in the distal plaque group. In conclusion, although hybrid surgery achieves similar outcomes in patients with ICA occlusion caused by either proximal or distal atherosclerotic plaques, plaque location may be a significant risk factor for successful recanalization of symptomatic non-acute long-segment ICA occlusion.

Clinical Factors Associated with Difficulty in Identifying the Recurrent Laryngeal Nerve in Thyroid Surgery

Clinical Factors Associated with Difficulty in Identifying the Recurrent Laryngeal Nerve in Thyroid Surgery

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

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. Laboratory experiment. 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. 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. Bioinformatics analysis confirmed divergent transcriptome profiles between the left-right ILMs. This preliminary study identifies putative gene targets that will characterize ILM laterality. N/A Laryngoscope, 134:3741-3753, 2024.

Long-term stimulation by implanted pacemaker enables non-atrophic treatment of bilateral vocal fold paresis in a human-like animal model

A wide variety of treatments have been developed to improve respiratory function and quality of life in patients with bilateral vocal fold paresis (BVFP). One experimental method is the electrical activation of the posterior cricoarytenoid (PCA) muscle with a laryngeal pacemaker (LP) to open the vocal folds. We used an ovine (sheep) model of unilateral VFP to study the long-term effects of functional electrical stimulation on the PCA muscles. The left recurrent laryngeal nerve was cryo-damaged in all animals and an LP was implanted except for the controls. After a reinnervation phase of six months, animals were pooled into groups that received either no treatment, implantation of an LP only, or implantation of an LP and six months of stimulation with different duty cycles. Automated image analysis of fluorescently stained PCA cross-sections was performed to assess relevant muscle characteristics. We observed a fast-to-slow fibre type shift in response to nerve damage and stimulation, but no complete conversion to a slow-twitch-muscle. Fibre size, proportion of hybrid fibres, and intramuscular collagen content were not substantially altered by the stimulation. These results demonstrate that 30 Hz burst stimulation with duty cycles of 40% and 70% did not induce PCA atrophy or fibrosis. Thus, long-term stimulation with an LP is a promising approach for treating BVFP in humans without compromising muscle conditions.

Single Institution Experience in the Management of Locally Advanced (pT4) Differentiated Thyroid Carcinomas

BackgroundLocally infiltrating (T4) differentiated thyroid carcinomas (DTC) represent a challenge. Surgical strategy and adjuvant therapy should be planned balancing morbidity and oncologic outcome. A series of patients with T4 DTC who underwent multidisciplinary evaluation and treatment is reported. The main study endpoints were the oncologic outcome, complication rates, and risk factors for tumor recurrence.Patients and MethodsAll DTC cases operated between 2009 and 2021 were reviewed and T4 DTC cases were identified. En bloc resection of inferior laryngeal nerve (ILN), tracheal, and/or internal jugular vein (IJV) was performed in cases of massive infiltration. In cases of pharyngoesophageal junction (PEJ) invasion, the shaving technique was always applied.ResultsAmong 4775 DTC cases, 60 were T4. ILN infiltration was documented in 45 cases (en bloc resection in 9), tracheal infiltration in 14 (tracheal resection in 2), PEJ invasion in 11 (R0 resection in 7 cases and < 1 cm residual tissue in 4 cases), IJV resection in 6, and laryngeal in 2. In total, 11 postoperative ILN palsy, 23 transient hypoparathyroidisms, and 2 hematomas requiring reoperation were registered. Final histology showed 7 pN0, 22 pN1a, and 31 pN1b tumors. Aggressive variants were observed in 47 patients. All but 1 patient underwent radioiodine treatment, 12 underwent adjuvant external beam radiation therapy (EBRT), and 2 underwent chemotherapy. At a median follow-up of 58 months, no tumor-related death was registered, and seven patients required reoperation for recurrence. Tracheal invasion was the only significant factor negatively impacting recurrence (p = 0.045).ConclusionsA multidisciplinary approach is essential for the management of T4 DTC. Individualized and balanced surgical strategy and adjuvant treatments, in particular EBRT, ensure control of locally advanced disease with acceptable morbidity.

Assessment of Changes in the Quality of Voice in Post-thyroidectomy Patients With Intact Recurrent and Superior Laryngeal Nerve Function.

Background Thyroidectomy is a routinely performed surgical procedure used to treat benign, malignant, and some hormonal disorders of the thyroid that are not responsive to medical therapy. Voice alterations following thyroid surgery are well-documented and often attributed to recurrent laryngeal nerve dysfunction. However, subtle changes in voice quality can persist despite anatomically intact laryngeal nerves. This study aimed to quantify post-thyroidectomy voice changes in patients with intact laryngeal nerves, focusing on fundamental frequency, first formant frequency, shimmer intensity, and maximum phonation duration. Methodology This cross-sectional study was conducted at a tertiary referral center in central India and focused on post-thyroidectomy patients with normal vocal cord function. Preoperative assessments included laryngeal endoscopy and voice recording using a computer program, with evaluations repeated at one and three months post-surgery. Patients with normal laryngeal endoscopic findings underwent voice analysis and provided feedback on subjective voice changes. The PRAAT version 6.2 software was utilized for voice analysis. Results The study included 41 patients with normal laryngoscopic findings after thyroid surgery, with the majority being female (85.4%) and the average age being 42.4 years. Hemithyroidectomy was performed in 41.4% of patients and total thyroidectomy in 58.6%, with eight patients undergoing central compartment neck dissection. Except for one patient, the majority reported no subjective change in voice following surgery. Objective voice analysis showed statistically significant changes in the one-month postoperative period compared to preoperative values, including a 5.87% decrease in fundamental frequency, a 1.37% decrease in shimmer intensity, and a 6.24% decrease in first formant frequency, along with a 4.35% decrease in maximum phonatory duration. These trends persisted at the three-month postoperative period, although values approached close to preoperative levels. Results revealed statistically significant alterations in voice parameters, particularly fundamental frequency and first formant frequency, with greater values observed in total thyroidectomy patients. Shimmer intensity also exhibited slight changes. Comparison between hemithyroidectomy and total thyroidectomy groups revealed no significant differences in fundamental frequency, first formant frequency, and shimmer. However, maximum phonation duration showed a significantly greater change in the hemithyroidectomy group at both one-month and three-month postoperative intervals. Conclusions This study on post-thyroidectomy patients with normal vocal cord movement revealed significant changes in voice parameters postoperatively, with most patients reporting no subjective voice changes. The findings highlight the importance of objective voice analysis in assessing post-thyroidectomy voice outcomes.

Robotic thoracic surgery for neurogenic tumors.

Thoracic neurogenic tumors usually present as benign nerve sheath tumors that can be resected via transthoracic or posterior approaches, depending on the anatomical location. Robot-assisted thoracic surgery (RATS) is increasingly being used for the transthoracic approach, but evidence is very limited. The authors initiated the current study to evaluate the efficacy and safety of RATS for thoracic neurogenic tumors. This retrospective study is based on a prospectively created database that includes all RATS surgeries between 2018 and 2023. All patients with histologically confirmed neurogenic tumors were included in the study. The patients' medical and surgical records as well as radiological and pathological findings were analyzed. During a 5-year period, 27 patients underwent robotic resection of neurogenic tumors at a high-volume thoracic surgery center. Two patients had previously undergone posterior laminectomy for resection of the intraspinal components. The pathologies included schwannomas (18, 64%), ganglioneuromas (8, 29%), 1 paraganglioma, and 1 neurofibroma occurring close to a schwannoma unilaterally in the same patient. The median tumor size was 4.7 cm (range 0.9-11.4 cm). The median operating time was 69 minutes (range 27-169 minutes), and the median postoperative stay was 3 days (range 1-19 days). There was one conversion due to adhesions after a previous surgery. No major bleeding occurred. There was no perioperative mortality. Morbidity included a lymphatic fistula (n = 1), pneumonia (n = 1), prolonged air leak (n = 1), and 4 cases of postoperative pain persisting for more than 4 weeks. Neurological complications were mostly observed in patients with tumors located at the thoracic apex: 2 cases of Horner's syndrome, 2 cases with compensatory hyperhidrosis, 1 patient with paresis of the recurrent laryngeal nerve, and a T1 lesion resulting in a minor motor deficit of the small hand muscles (Medical Research Council grade 4) and hypoesthesia of the respective dermatome. RATS for thoracic neurogenic tumors is feasible and safe. Tumors at the thoracic apex are at high risk of neurological deficit and should be approached with care. Close interdisciplinary collaboration between neurosurgeons and thoracic surgeons is necessary for optimal patient selection and a good postoperative outcome.

Analysis of vocal fold movement characteristics in patients with laryngeal neurogenic injury

Objective:To analyze the characteristics of vocal fold movement and glottic closure in patients with laryngeal neurogenic injury. Methods:A total of 185 patients with vocal fold paralysis diagnosed by laryngeal electromyography as neurogenic damage to cricothyroid muscle, thyreoarytenoid muscle and posterior cricoarytenoid muscle were enrolled, they were divided into unilateral vocal fold paralysis group and bilateral vocal fold paralysis group, respectively, and superior laryngeal paralysis group, recurrent laryngeal nerve paralysis group and vagal nerve paralysis group according to nerve injury. The characteristics of vocal fold movement and glottic closure were analyzed under strobe laryngoscope. The qualitative evaluation of vocal fold movement was fixed vocal fold, reduced vocal fold movement and normal vocal fold movement, and the qualitative evaluation of glottic closure was glottic closure and glottic imperfection. The results were analyzed statistically. Results:The proportion of normal, reduced and fixed vocal fold motion in bilateral vocal fold paralysis group was significantly different from that in unilateral vocal fold paralysis group（P<0.05）, the composition of normal and reduced vocal fold motion in bilateral vocal fold paralysis group（47.70%） was significantly greater than that in unilateral vocal fold paralysis group（12.27%）. There was no significant difference between the proportion of glottic closure and glottic imperfecta in bilateral vocal fold paralysis group and unilateral vocal fold paralysis group（P<0.05）. The proportion of decreased vocal fold motion in superior laryngeal nerve paralysis group（50.00%） was higher than that in recurrent laryngeal nerve paralysis group（9.32%） and vagal nerve paralysis group（9.00%）. The proportion of decreased and fixed vocal fold motion in superior laryngeal nerve paralysis group, recurrent laryngeal nerve paralysis group and vagal nerve paralysis group was statistically significant（P<0.05）.There was no significant difference in glottic closure among the three groups（P<0.05）. Conclusion:Vocal fold movement characteristics of patients with laryngeal neurogenic injury were mainly vocal fold fixation, or normal or weakened vocal fold movement. There may be missed diagnosis of unilateral vocal fold paralysis in clinical practice. In half of the patients with superior laryngeal nerve palsy, vocal fold movement is characterized by vocal fold fixation.