To Identify the Dangerous Length of External Laryngeal Nerve In Relation to Thyroid Pole In Cadaveric Thyroid Glands

Introduction: The external laryngeal nerve passes through the “space of Reeve” cricothyroid space. It has also been described as lying in the Joll’s triangle. It is often inadvertently neglected during thyroid surgeries. It has been named after a singer who lost her voice after a thyroid surgery, as the “nerve of Galli Curci” Aim: To identify the dangerous length of the external laryngeal nerve in relation to the thyroid pole. Material and Methods: Fifty laryngeal nerves were dissected using conventional method of dissection, in twentyfive embalmed cadavers used for teaching purpose at Karpaga Vinayaga Institute of Medical Sciences and Research, Madurantakam. The observations were noted and photographs taken. The course and relations were carefully noted. Results: 38 specimens (76%) had the superior laryngeal nerve measuring 4cm. in 8 specimens (16%) it was 3.5 cm and in 04 specimens (8%) it measured 3.8 cm. It was observed that the external laryngeal nerve crossed the superior thyroid pole at less than 1cm only in three (6%) of the fifty nerves. Conclusions: The critical length of the nerve would be dangerous if the nerve crosses the superior thyroid pedicle close to thyroid pole at less than 1 cm. The consequences of neglecting the critical length would injure the nerve and cause dysphonia or raspy voice.

Predictive factors and risk analysis of recurrent laryngeal nerve invasion in papillary thyroid carcinoma ≤ 1 cm

ABSTRACT Objective: The recurrent laryngeal nerve (RLN) may be involved by papillary thyroid carcinoma ≤ 1 centimeter (PTC ≤ 1 cm). Current study investigated the predictive factors of RLN invasion in PTC ≤ 1 cm, the risk factors of disease recurrence in RLN invaded cases and the results of surgical management for RLN invasion. Materials and methods: Data of 374 PTC ≤ 1 cm patients were retrospectively collected. We performed univariate and multivariate analysis to identify predictive factors of RLN invasion and risk factors of disease recurrence. The abilities of factors in predicting RLN invasion were evaluated. Surgical outcomes and recurrence free survival (RFS) of patients were analyzed. Results: A total of 28 patients suffered RLN invasion, among which seven had disease recurrence. Preoperative vocal cord palsy (VCP), gross extrathyroidal extension, larger tumor size and tumor on the dorsal side of thyroid were verified as predictive factors of RLN invasion. RLN involved patients had poorer RFS, but better than those who also had upper-aerodigestive tract invasion. Upper-aerodigestive tract invasion, lateral neck lymph nodes metastasis (LNM) and BRAF V600E mutation were independent risk factors of disease recurrence in RLN invaded cases. Tumor shaving showed better RLN function preservation without increasing recurrent risk. Conclusions: Current study confirmed the rarity of RLN invasion in PTC ≤ 1 cm. Various aggressive features were verified as predictive factors of RLN invasion. Tumor shaving showed superiority in preserving nerve function without increasing recurrent risk. Special attentions should be paid for disease recurrence when RLN invasion accompanied by upper-aerodigestive tract invasion, lateral neck LNM or BRAF V600E mutation.

Menor aerolización con bloqueo del nervio laríngeo superior comparado con lidocaína intravenosa a la extubación / Less aerolization with superior laryngeal nerve block compared to intravenous lidocaine at extubation

Resumen: Introducción: La tos es una respuesta fisiológica de protección de la vía aérea, produce aerosoles que se identifican por imagen y alcanza una velocidad de hasta ocho metros por segundo. La extubación produce tos, hipertensión, taquicardia, apnea y laringoespasmo, existen métodos para minimizar su aparición. Debido a la pandemia de COVID-19 se han utilizado como profilaxis del reflejo tusígeno, la lidocaína intravenosa y el bloqueo del nervio laríngeo superior. El objetivo fue compararlos en la inhibición de la tos. Material y métodos: Se seleccionaron pacientes entre 18-60 años, cirugía electiva con anestesia general balanceada, ASA 1-3, con intubación menor a tres horas. Se aleatorizó un total de 90 pacientes, 45 en cada grupo, se eliminó un total de 10 pacientes por presentar inestabilidad hemodinámica al final de la cirugía o por no administrar dosis intravenosa de lidocaína en el tiempo establecido. Resultados: No hubo diferencia estadísticamente significativa en el número de pacientes que presentaron tos en ambos grupos (13 vs 10, p = 0.4684), de éstos se obtuvo una diferencia estadísticamente significativa en el número de decibeles a favor del grupo de bloqueo (75.6 vs 67, p < 0.001). Conclusiones: El bloqueo (selectivo) presenta menos aerolización que la lidocaína intravenosa en la extubación.

Abstract: Introduction: Coughing is a physiological response to protect the airway, it produces aerosols that are identified by imaging reaching a speed of up to 8 meters per second. Extubation produces cough, hypertension, tachycardia, apnea and laryngospasm, there are methods to minimize its occurrence. Due to the COVID-19 pandemic, intravenous lidocaine and superior laryngeal nerve block have been used as cough reflex prophylaxis. The aim was to compare them in cough inhibition. Material and methods: Patients aged 18-60 years, elective surgery with balanced general anesthesia, ASA 1-3, with intubation less than 3 hours, were selected. A total of 90 patients were randomized, 45 in each group. A total of 10 patients were eliminated because they presented hemodynamic instability at the end of surgery, and because the intravenous dose of lidocaine was not administered within the established time. Results: There was no statistically significant difference in the number of patients who presented cough in both groups (13 vs 10, p = 0.4684), of these there was a statistically significant difference in the number of decibels in favor of the block group (75.6 vs 67, p < 0.001). Conclusions: Block presents less aerolization than intravenous lidocaine in extubation.

Rehabilitación del nervio recurrente laríngeo postiroidectomía / Recurrent laryngeal nerve rehabilitation after thyroidectomy

El carcinoma papilar tiroideo es el tipo de cáncer más común de esta glándula, y su tratamiento de elección es la tiroidectomía. Entre las complicaciones asociadas resalta la parálisis de las cuerdas vocales, la cual ocurre por una lesión directa del nervio laríngeo recurrente durante la cirugía. Se presenta una paciente de 22 años de edad con este diagnóstico, a la cual se le realizó una tiroidectomía total; en el postoperatorio inmediato la paciente comenzó con estridor laríngeo intenso que requirió una traqueotomía de urgencia. En el examen físico se constató una parálisis bilateral de las cuerdas vocales y se decidió comenzar un tratamiento de rehabilitación del nervio recurrente laríngeo con laserterapia y HIVAMAT-200 como modalidades combinadas. Los resultados alcanzados con la fisioterapia fueron satisfactorios y la paciente se reintegró rápidamente a su ámbito familiar, escolar y social.

Papillary thyroid carcinoma is the most common type of cancer of this gland, and its treatment of choice is thyroidectomy. Vocal cord paralysis stands out among the associated complications, in which a direct injury to the recurrent laryngeal nerve occurs during surgery. We present a 22-year-old female patient with this diagnosis, who underwent a total thyroidectomy; in the immediate postoperative period the patient began with intense laryngeal stridor requiring an emergency tracheotomy. Physical examination revealed bilateral vocal cord paralysis and it was decided to begin rehabilitation treatment of the recurrent laryngeal nerve with laser therapy and HIVAMAT-200 as combined modalities. The results achieved with physiotherapy were satisfactory and the patient was quickly reintegrated into her family, school and social environment.

Characteristics of lymph node metastasis of right recurrent laryngeal nerve in thoracic esophageal squamous cell carcinoma / 中华肿瘤杂志

Objective: To understand the characteristics and influencing factors of lymph node metastasis of the right recurrent laryngeal nerve in thoracic esophageal squamous cell carcinoma (ESCC), and to explore the reasonable range of lymph node dissection and the value of right recurrent laryngeal nerve lymph node dissection. Methods: The clinicopathological data with thoracic ESCC were retrospectively analyzed, and the characteristics of lymph node metastasis along the right recurrent laryngeal nerve and its influencing factors were explored. Results: Eighty out of 516 patients had lymph node metastasis along the right recurrent laryngeal nerve, the metastasis rate was 15.5%. Among 80 patients with lymph node metastasis along the right recurrent laryngeal nerve, 25 cases had isolated metastasis to the right recurrent laryngeal nerve lymph node but no other lymph nodes. The incidence of isolated metastasis to the recurrent laryngeal nerve lymph node was 4.8% (25/516). A total of 1 127 lymph nodes along the right recurrent laryngeal nerve were dissected, 115 lymph nodes had metastasis, and the degree of lymph node metastasis was 10.2%. T stage, degree of tumor differentiation and tumor location were associated with right paraglottic nerve lymph node metastasis (all P<0.05). The lymph node metastasis rate along the right recurrent laryngeal in patients with upper thoracic squamous cell carcinoma (23.4%, 26/111) was higher than that of patients with middle (13.5%, 40/296) and lower (12.8%, 14/109) thoracic squamous cell carcinoma (P=0.033). In patients with poorly differentiated ESCC (20.6%, 37/180) the metastasis rate was higher than that of patients with moderately (14.6%, 39/267) and well-differentiated (5.8%, 4/69; P<0.05). The lymph node metastasis rate of patients with stage T4 (27.3%, 3/11) was higher than that of patients with stage T1 (9.6%, 19/198), T2 (19.0%, 16/84) and T3 (18.8%, 42/1 223; P<0.05). Multivariate regression analysis showed that tumor location (OR=0.61, 95% CI: 0.41-0.90, P=0.013), invasion depth (OR=1.46, 95% CI: 1.11-1.92, P=0.007), and differentiation degree (OR=1.67, 95% CI: 1.13-2.49, P=0.011) were independent risk factors for lymph node metastasis along right recurrent laryngeal nerve of ESCC. Conclusions: The lymph node along the right recurrent laryngeal nerve has a higher rate of metastasis and should be routinely dissected in patients with ESCC. Tumor location, tumor invasion depth, and differentiation degree are risk factors for lymph node metastasis along right recurrent laryngeal nerve in patients with ESCC.

Neuropatía laríngea y movimiento paradojal de cuerdas vocales en la edad pediátrica: reporte de un caso / Laryngeal neuropathy and paradoxical vocal fold motion in the pediatric age: case report

Resumen La neuropatía laríngea es una condición de hipersensibilidad, hiperreactividad e hiper-función laríngea secundaria a un desequilibrio entre las aferencias y eferencias laríngeas. La respuesta individual y exagerada frente a diversos gatillantes específicos puede generar síntomas como tos crónica, parestesia laríngea, carraspera, disfonía, estridor, sensación de globus faríngeo, movimiento paradojal de las cuerdas vocales (también conocido como disfunción cordal) y/o laringoespasmo. Existe abundante literatura sobre neuropatía laríngea en adultos, sin embargo, en niños es limitada. El objetivo de este artículo es dar a conocer un caso de neuropatía laríngea en la edad pediátrica y la importancia de su consideración en el enfrentamiento de estos pacientes. Se presenta caso clínico de un paciente de 13 años, con antecedente de cirugía cardiaca reciente, evoluciona con disfonía severa evidenciándose aparente inmovilidad cordal bilateral con resultados discordantes entre nasofibrolaringoscopía y electromiografía laríngea. Posteriormente presenta mejorías en su voz, sin embargo, se agregan otros síntomas laringológicos como carraspera, globus faríngeo y estridor no explicados por causas anatómicas. Se expone la evaluación y abordaje otorrinolaringológico-fonoaudiológico para el caso. Se concluye que el diagnóstico de neuropatía laríngea requiere un alto índice de sospecha clínica ante signos laringológicos sugerentes, debiendo descartarse causas orgánicas y estructurales. El abordaje otorrinolaringológico-fonoaudiológico constituye el pilar terapéutico asociado al uso de neuromoduladores en casos seleccionados.

Abstract Laryngeal neuropathy is a condition of hypersensitivity, hyperresponsiveness and laryngeal hyperfunction secondary to an imbalance between laryngeal afferent and efferent information. The individual and exaggerated response to diverse specific triggers can lead to symptoms such as chronic cough, laryngeal paresthesia, throat clearing, dysphonia, stridor, globus pharyngeus, vocal cord dysfunction, and/or laryngospasm. There is plentiful literature on laryngeal neuropathy in adults, however, in children, it is limited. Here, we present a case report of laryngeal neuropathy in the pediatric age and discuss the importance of its consideration in the approach of these patients. A case of a 13-year-old patient, recently intervened with cardiac surgery that evolves with severe dysphonia is presented. Nasofibrolaryngoscopy shows apparent bilateral vocal fold immobility with discordant results in laryngeal electromyography. Later, his voice improves but other laryngological symptoms appeared, such as throat clearing, globus pharyngeus and stridor, not explained by anatomical causes. The otolaryngological-speech therapy evaluation and approach for the case is exposed. We conclude that for the diagnosis of laryngeal neuropathy, a high index of clinical suspicion is required in the presence of suggestive laryngological symptoms, and organic and structural causes must be previously ruled out. The otorhinolaryngological-logopedic approach constitutes the mainstay of treatment associated with the use of neuromodulators in selected cases.

Comparison of Ultrasound / Anatomical landmark guided technique for superior laryngeal nerve block along with Topical Anesthesia for awake nasal intubation in various Oral& faciomaxillary & Dental surgeries

ABSTRACT:Background: Endotracheal intubation is gold standard of general anesthesia. various oral,Maxillofacial, Dental surgeries are carried out in high-risk patients having chances ofdifficult intubation. If we give sedation or general anesthesia, we can be trapped in criticalairway accidents.Aims & objectives: To access & compare efficacy of anatomical landmark guided/Ultrasound guided superior laryngeal nerve block associated with topical Anesthesia &transtracheal block for awake blind nasal intubation.Method:Group A: Anatomical landmark guided superior laryngeal nerve block given(n=30)Group B: ultrasound guided superior laryngeal nerve block(n=30)In both groups topical Anesthesia & transtracheal block for awake blind nasal intubation wasgiven.Results: upper airway block provide clinical ease to facilitate blind nasal awake intubation.ultrasound guided block has less adverse reactions.Conclusion: Both methods provide good quality of Endotracheal intubation, but ultrasoundguided block is more efficient & scientific method to block superior laryngeal nerve forawake nasal intubation.

Utilidad de la neuromonitorización vagal continua en cirugía tiroidea: experiencia y resultados en un hospital de tercer nivel / The role of continuous vagal intraoperative nerve monitoring in thyroid surgery: experience and results in a third-level hospital

Resumen Objetivo: La lesión del nervio laríngeo recurrente es una grave complicación en cirugía tiroidea. El propósito del presente estudio es analizar la utilidad de la neuromonitorización vagal continua intraoperatoria en un hospital terciario. Materiales y Método: Estudio observacional, analítico y retrospectivo que recoge pacientes intervenidos de cirugía tiroidea con neuromonitorización en un período de 14 meses. La pérdida de señal se define como amplitud final nerviosa < 100 ^V, realizándose laringoscopia postquirúrgica ante la sospecha de lesión nerviosa. El análisis estadístico se realizó con el programa SPSS® V25,0, con p < 0,05. Resultados: Se incluyeron 120 pacientes intervenidos, registrándose en el 24,2% pérdida de señal. Factores de riesgo para lesión fueron bocio intratorácico (OR 5,31; IC 95% 1,56-17,99; p = 0,007), cirugía cervical previa (OR 5,76; IC 95% 0,64-51,97; p = 0,119) y patología maligna (OR 1,44; IC 95% 0,16-12,79; p = 0,743). Fue posible el cambio de estrategia quirúrgica en 7 casos. En el seguimiento posterior se cuantificó parálisis recurrencial transitoria en 27 pacientes y permanente en 4. Discusión: La neuromonitorización parece reducir la incidencia de parálisis laríngea porque aumenta la seguridad en la identificación del nervio recurrente y reduce su manipulación durante la cirugía. Conclusiones: La neuromonitorización intraoperatoria es útil para identificar el nervio laríngeo recurrente y advierte del riesgo potencial de lesión, permitiendo cambiar la estrategia quirúrgica para evitar la parálisis bilateral de cuerdas vocales.

Aim: Recurrent laryngeal nerve injury is a serious complication in thyroid surgery. The purpose of the present study is to analyze the use of intraoperative continuous vagal neuromonitoring in a tertiary hospital. Materials and Method: Observational, analytical and retrospective study that includes patients who underwent thyroid surgery with neuromonitoring in a period of 14 months. Loss of signal is defined as final nerve amplitude < 100 ^V, and postsurgical laryngoscopy is performed due to suspicion of nerve injury. Statistical analysis was performed with the SPSS® V25.0 program, with p < 0.05. Results: 120 operated patients were included, registering loss of signal in 24.2%. Risk factors for injury were intrathoracic goiter (OR 5.31; 95% CI 1.56-17.99; p = 0.007), previous cervical surgery (OR 5.76; 95% CI 0.64-51.97; p = 0.119) and malignant pathology (OR 1.44; 95% CI 0.16-12.79; p = 0.743). A change in surgical strategy was possible in 7 cases. In the subsequent follow-up, transient recurrent paralysis was quantified in 27 patients and permanent in 4. Discussion: Neuromonitoring seems to reduce the incidence of laryngeal paralysis because it increases the security in the identification of the recurrent nerve and reduces its manipulation during surgery. Conclusions: Intraoperative neuromonitoring is useful to identify the recurrent laryngeal nerve and warns of the potential risk of injury, allowing to change the surgical strategy to avoid bilateral vocal cord paralysis.

Selecting the Right Plane of Dissection in Thyroidectomy: Along the Recurrent Laryngeal Nerve or the Thyroid Capsule? A Retrospective Analysis

Abstract Introduction Total thyroidectomy remains highly technical, with a significant risk of recurrent laryngeal nerve (RLN) compromise and hypoparathyroidism. After identifying RLN, at the level of the ligament of Berry, local factors may compel the surgeon to either dissect along the nerve or the thyroid capsule. Objective The objective of the present study is to compare these two approaches in terms of outcomes and complication rates. Methods This is a retrospective analysis from September, 2013 to April 2019 of 511 consecutive patients undergoing thyroidectomy. General demographics and disease parameters were recorded. At the discretion of the surgeon and according to the demands of the local operative factors, the patients either had dissection along the RLN or along the thyroid capsule. Perioperative and postoperative parameters such as blood loss, duration of surgery, hospital stay, pain scores, analgesia requirements and complications were recorded. The groups were compared with the Pearson chi-squared test or with the Fisher exact test. A p-value < 0.05 was considered statistically significant. Results The incidence of transient hypocalcaemia and transient RLN compromise were higher when dissection was performed along the nerve as opposed to the plane along the thyroid capsule. Other parameters including operative time, hospital stay, pain scores, analgesia requirement, wound infection, seroma, hemorrhage, and recurrence did not differ between the groups. Subgroup analysis of the patients who presented with complications showed that local factors, malignancy, and extent of surgery correlated positively with complications when dissected along the RLN. Conclusion Dissection along the capsule of the thyroid during thyroidectomy is a safer plane in terms of low rate of transient RLN injury and hypoparathyroidism as opposed to dissection along the nerve.

A Prospective Study on Relation of Inferior Thyroid Artery with Recurrent Laryngeal Nerve at the Base of Thyroid Gland in Tamil Nadu Population

Background: The risk of injuring recurrent laryngeal nerves which can result in voice or swallowing problems can be a major complication during thyroid surgeries. Intraoperative injury to RLN can be an issue and can have a detrimental impact on patients’ quality of life. The incidence of injury to recurrent laryngeal nerve worldwide ranges from 0.5 to 20%. To prevent such surgical complications of thyroid, a detailed anatomy of inferior vascular pedicle (inferior thyroid artery) and its relation to adjacent recurrent laryngeal nerve is required. Aim: The aim of the study was, To find out the variable anatomical relationship between inferior thyroid artery and recurrent laryngeal nerve at the base of lateral lobes of thyroid gland. Materials and methods: This descriptive study was conducted for a period of 72 months at the Department of Anatomy, Government Medical College, Omandurar Government Estate, Chennai-2, between January 2015 – January 2021 by dissection method in 60 adult (54 male and 6 female) cadavers (60 – right & 60 – left sides). Results: Results were noted, tabulated and interpreted. It was found that the recurrent laryngeal nerve at the base of thyroid gland which was predominantly posterior on both sides (R-78.33%, L- 100%) to inferior thyroid artery and in 21.66% anterior to ITA on right. Conclusion: The recurrent laryngeal nerve may lie anterior or posterior to inferior thyroid artery. In the present study, the recurrent laryngeal nerve was posterior most commonly on both sides to inferior thyroid artery. On the right, the second common presentation was the recurrent laryngeal nerve lying anterior to inferior thyroid artery.

A Case of Decreased Swallowing Function Due to Cardiac Myxoma / 日本プライマリ・ケア連合学会誌

The case was a 77-year-old man. He had dizziness and dysphagia for 2 years, and underwent detailed screening at the internal medicine department for general malaise and bloody sputum. He was hospitalized for aspiration pneumonia due to dysphagia of unknown origin. This time, he visited a local doctor with palpitations and shortness of breath. Echocardiography indicated a left atrial tumor involving the mitral valve and arrhythmia. Emergency surgery was performed to remove the left atrial myxoma and close the patch at our hospital's cardiovascular surgery department. After the excision, swallowing function was restored, and the patient was diagnosed with postoperative Ortner's syndrome. We report a case where echocardiography was considered important as a detailed investigation of the cause of swallowing dysfunction and dizziness.

Exploration of deep learning to identify recurrent laryngeal nerve in endoscopic thyroidectomy via unilateral axillary approach / 中华内分泌外科杂志

Objective:To explore whether deep learning could apply to recognize the recurrent laryngeal nerve in the video of unilateral axillary approach endoscopic thyroidectomy.Methods:Videos of endoscopic thyroidectomy via unilateral axillary approach in Peking Union Medical College Hospital from Jul. 1st, 2020 to May. 1st, 2021 were collected. Videos containing the recurrent laryngeal nerve were selected, and the outline of recurrent laryngeal nerve were marked by two senior thyroid surgeons and staffs. Data were divided into training set and test set in a ratio of 5:1, and classified into high, medium and low recognition group according to difficulty of recognizing the outline of the nerve. The neuron network was based on PSPNet combined with Resnet50. All data were analyzed by R (ver. 4.0.2) .Results:A total of 38 videos including 35,501 frames of pictures were included in this study. 29, 704 frames of 32 videos were in our training set and 5797 frames of 6 videos were in the test set. When the intersection over union (IOU) threshold is 0.1, the sensitivity and precision is 100.0%/92.1%, 95.8%/80.2% and 81.0%/80.6% in high, medium and low recognition group respectively. When the IOU threshold is 0.5, the sensitivity and precision is 92.6%/85.3%, 71.7%/60.5% and 38.1%/37.9% in high, medium and low recognition group respectively, indicating that neuron network could located the outline of recurrent laryngeal nerve in high and medium recognition group. False negatives were often due to small targets and unclear boundaries.Conclusion:Recurrent laryngeal nerve recognition based on deep learning is feasible and has potential application value in endoscopic thyroidectomy, which may help surgeons reduce the risk of accidental injury of recurrent laryngeal nerve and improve the safety of thyroidectomy.

Application and progress of intraoperative neuromonitoring techniques in robotic thyroid surgery / 中华内分泌外科杂志

Robotic surgical systems are gradually being used in minimally invasive surgery with their advantages of high-definition magnified 3D images, stable surgical field and flexible operation. The change of surgical approach and the narrow operating space in robotic thyroid surgery have made it more difficult to identify and protect the laryngeal nerve, and the application of nerve monitoring has been limited. Many researchers have attempted to improve the monitoring equipment and probe placement to make intraoperative neuromonitoring techniques work well in robotic thyroid surgery. In this paper, we seek effective ways to protect the laryngeal nerve in robotic thyroid surgery, and lay the foundation for a more minimally invasive and standardized development of this technology.

Clinical study of non-recurrent laryngeal nerve in thyroid surgery / 中华内分泌外科杂志

Non-recurrent laryngeal nerve (NRLN) is a rare anatomic variation of the recurrent laryngeal nerve, which is often associated with right subclavian artery variation on the right side and more rare on the left side, usually accompanied with visceral inversion. Injury will lead to permanent paralysis of the vocal cord, bilateral nerve injury will even contribute to dyspnea in patients, breathing only with the aid of ventilator, in which case postoperative tracheotomy treatment is needed, leading to obvious influence on the daily life of patients. We reviewed the progress of NRLN in terms of histology and embryology development, anatomical classification, improvement and identification of related preoperative examination, intraoperative nerve identification, exploration and protection, and postoperative injury response, with the aim to provide some reference for improvement of thyroid surgery in clinical diagnosis and treatment.

The influence of loss of intraoperative nerve monitoring signal on decision-making of total thyroidectomy: similarities and differences between Chinese and western perspectives / 中华内分泌外科杂志

With the popularization of intraoperative nerve monitoring (IONM) , it is possible to determine the intraoperative nerve function, which provides evidence-based basis for surgical decision making. Intraoperative loss of nerve signal (LOS) often indicates postoperative vocal cord dyskinesia. Once LOS occurs intraoperatively, the next surgical strategy adopted by the operator has always been controversial among Chinese and western experts. Therefore, this paper makes a comparative analysis of the differences between the viewpoints of domestic experts and western scholars and the possible causes through the investigation of domestic and foreign literature to provide theoretical basis for better thyroid surgery decision.

Modified transcricothyroid electrode recording method for monitoring recurrent laryngeal nerve function during thyroidectomy / 中华内分泌外科杂志

Objective:To study the safety, validity and practicability of the modified trans-cricothyroid needle electrode method for neurmonitoring during thyroidectomy.Methods:115 patients from the Department of Thyroid Surgery in Peking University Shenzhen Hospital scheduled for thyroid surgery were recruited into the group. Two paired needle electrodes were obliquely inserted into the cricothyroid membrane from the angle between the rectus cricothyroid muscle and the inferior margin of thyroid cartilage. The function of recurrent laryngeal nerve (RLN) was localized, exposed and evaluated by standard four-step method (V1-R1-R2-V2) . The vocal cord movement was evaluated by electronic laryngoscope before and after operation, and t-test was used to compare the difference of EMG signal amplitude before and after operation.Results:A total of 130 RLN from 115 patients were recorded effective electromyographic (EMG) signals, including 12 cases of giant goiter with tracheal compression stenosis; 13 cases had repeated adjustments of the position of tracheal intubation electrode during operation, but EMG signals were not satisfactory; 15 cases were with of accidental findings during operation and requiring neurmonitoring, but tracheal intubation electrodes were not used in advance. 75 cases were volunteers. The signals of 3 RLN were lost during operation. On the second day after operation, electronic laryngoscope showed that 2 cases had normal vocal cord movement and 1 case had vocal cord paralysis and no recovery for 6 months follow-up. The EMG signals of other 127 nerves were V1/R1=1857±1718μV/2347±2323μV, V2/R2=1924±1705μV/2450±2345μV. There was no significant difference in EMG signals between pre-operation and post-operation ( t=0.31/0.35, P=0.755/0.725) . The electronic laryngoscope showed normal vocal cord movement before and after operation. During the operation, 2 patients had a little bleeding at the needle electrode insertion point, which stopped after 5 minutes of compression. No electro-acupuncture breakage, infection or local hematoma occurred. Conclusions:The modified trans-cricothyroid needle electrode method had been proved to be safe and feasible for evaluating the function of recurrent laryngeal nerve in thyroid surgery. Besides of unaffected by tracheal conditions, it has good stability, simple implantation and low cost. In thyroid surgery, it can be used as a useful supplement to endotracheal intubation electrode.

Clinical study of parathyroidectomy with small incision in the lateral cervical region / 中华内分泌外科杂志

Objective:To evaluate the clinical feasibility, safety, and advantages of small lateral cervical incision for parathyroid exploration and resection.Methods:A total of 31 consecutive patients who underwent parathyroidectomy with a small lateral cervical incision, in the Department of Endocrinology and Breast Surgery of the First Affiliated Hospital of Chongqing Medical University from Apr. to Nov. 2021, including 11 males and 20 females, aged (49.32±13.79) years, ranging from 28 to 86 years, were selected to make retrospective statistical analysis of the surgical time, hospital stay, intraoperative blood loss, postoperative drainage and postoperative complications of the patients. All patients were injected with carbon nanoparticles suspension injection guided by color ultrasound to locate the enlarged parathyroid gland before surgery. EXCEL 2019 software was used for statistical analysis.Results:Thirty-one patients underwent parathyroidectomy through a small lateral cervical incision. Primary hyperparathyroidism was performed in 19 cases (including 2 cases with bilateral small lateral cervical incision, 2 cases with unilateral excision of thyroid mass combined with parathyroidectomy, 1 case with resection of huge parathyroid adenoma, and 1 case with local anesthesia) . Twelve patients with secondary hyperparathyroidism underwent total parathyroidectomy through bilateral small lateral cervical incision and forearm autogenous parathyroid transplantation (including bilateral thyroid mass resection combined with bilateral total parathyroidectomy and forearm autogenous parathyroid transplantation in 2 cases, local anesthesia and cervical plexus nerve block in 2 cases, and ectopic parathyroid gland in thyroid in 1 case) . Among them, the average operative time of patients with primary hyperparathyroidism was (54.74±27.71 & 74.14±31.73) min, the average intraoperative blood loss was (8.11±5.05 & 14.43±10.94) ml, the average postoperative drainage was (14.37±24.64 & 26.36±32.87) ml, the average postoperative parathyroid hormone was (11.59±16.46 & 26.65±56.38) pg/ml, the average hospital stay was (10.00±5.09 & 10.96±4.55) d, and the postoperative complication rate was (3.2% & 0%) .Conclusions:Parathyroid gland exploration and resection through small lateral cervical incision is a safe and effective surgical method and can also complete thyroid exploration and parathyroidectomy at the same time. Appropriate anesthesia should be selected after a full assessment of the patient’s basic condition.

Application of da Vinci robotics in thyroid surgery: a summary of clinical experience of 304 cases in a single center / 中华内分泌外科杂志

Objective:To investigate the clinical effectiveness of da Vinci robotics in thyroid surgery.Methods:304 cases of robotic thyroid surgery performed by the same experienced surgeon at the Department of Thyroid Surgery, China-Japan Union Hospital of Jilin University during the period from Apr. 3, 2020 to Nov. 5, 2021 were prospectively included, and the operation time, operation type, postoperative drainage, postoperative hospital stay, total number of lymph node dissection and number of positive lymph nodes, operation complications, and postoperative pain level of all patients were counted. The learning curve was plotted by applying the moving average method, divided into the initial stage and the mature stage, and the differences in surgical outcomes and surgical complications between the two stages were compared. SPSS 23.0 was applied for statistical analysis, and t-test and Mann-Whitney U test were used for comparison of measurement data, and χ2 test was used for comparison of count data. Result:All surgeries were completed successfully without conversion to open cases, including 29 males and 275 females, with a mean age of (33.8±8.9) years and a range of 27-41 years. The mean body mass index (BMI) was (22.9±3.6) kg/m 2 and a range of 20.5-25.4 kg/m 2. The median operative time was 140 min, the median postoperative drainage was 52.5 ml, and the median postoperative hospital stay was 3 days. The mean number of lymph nodes cleared was 4.4±3.5, and the mean number of positive lymph nodes was 0.9±1.7. The incidence of postoperative transient laryngeal nerve (RLN) injury was 3.3%, and the incidence of transient hypoparathyroidism was 0.7%. A significant decrease in operative time occurred after the 26th case and subsequently stabilized. Compared with the initial stage of the learning curve, the mature stage had a shorter operative time (146.0±36.5 vs 198.7±56.7 min, P<0.001) , a lower incidence of temporary RLN injury (2.5% vs 11.5%, P<0.05) , and a lower percentage of benign tumor surgery (12.2% vs 26.9%, P<0.05) . Conclusion:The application of robotic technology in thyroid surgery is safe and reliable, and its successful implementation should follow a corresponding learning curve, from easy to difficult, with different surgical approaches selected according to the patient’s condition, wishes, and the operator’s technical level.

Application of deep learning to identify recurrent laryngeal nerve in endoscopic thyroidectomy via breast approach / 中华内分泌外科杂志

Objective:To explore whether deep learning could apply to recognize the recurrent laryngeal nerve (RLN) in videos of endoscopic thyroidectomy (ETE) via breast approach.Methods:Videos of ETE via breast approach in Peking Union Medical College Hospital from Feb. 2020 to Aug. 2021 were collected. Videos containing RLN were selected, and the outline of RLN was marked by two thyroid surgeons. Then data were divided into a training set and a test set in a ratio of 5:1 and classified into the high and low difficulty group according to a senior thyroid surgeon’s opinion. Those pictures were input to D-LinkNet model. Precision, sensitivity and mean dice index was calculated.Results:A total of 46 videos including 153, 520 frames of pictures were included in this study. 131,039 frames of 39 videos were in the training set and 22,481 frames of 7 videos were in the test set. When the intersection over union threshold was 0.1, the sensitivity and precision was 92.9%/72.8% and 47.6%/54.9% in high and low recognition group, respectively. When the intersection over union threshold was 0.5, the sensitivity and precision turned to 85.8%/67.2% and 37.6%/43.5% in high and low difficulty group, respectively. Mean Dice index was 0.781 and 0.663 in high and low difficulty group, respectively.Conclusions:RLN recognition based on deep learning is feasible and has potential application value in ETE, which may help surgeons reduce the risk of accidental injury of RLN and improve the safety of thyroidectomy.

The value and related complications of lymph node dissection along bilateral recurrent laryngeal nerves in esophageal cancer patients / 中华肿瘤杂志

Esophageal cancer is one of the most common malignant tumors of digestive tract, lymph node metastasis is a frequently encountered metastasis in the esophageal cancer patients. The number of lymph node metastasis is reported as an important prognostic factor, and it also affects the choice of postoperative treatments in the esophageal cancer. It was reported that the recurrent laryngeal nerve lymph nodes are the most common sites of nodal metastasis and need to be completely dissected during the esophagectomy for thoracic esophageal cancers. Dissection of the lymph nodes along bilateral recurrent laryngeal nerves not only improves the accuracy of staging, but also improves postoperative survival of esophageal cancer patients due to reducing the local recurrence. However, it also brings problems such as injury of laryngeal recurrent nerves, and increases postoperative complications such as pulmonary complications and malnutrition due to aspiration and coughing. Therefore, it is necessary to preserve the structure and function of bilateral recurrent laryngeal nerves during esophagectomy through careful manipulations, and minimize the impact of complications in prognosis and quality of life from injury to the recurrent laryngeal nerve.