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.

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.

Comparison of Recurrent Laryngeal Nerve Injury during Thyroidectomy with and Without Routine Identification of the Nerve Peroperatively.

Thyroidectomy is one of the commonest operative procedures performed in the neck and injury to recurrent laryngeal nerve (RLN) is not uncommon. It results in hoarseness to serious respiratory distress depending on the extent of the injury. The incidence of RLN injury varies widely and is multifactorial depending on the extent of surgical procedures, experience and expertise of the surgeons, nature of the thyroid diseases and a wide range of anatomical variations. Peroperative routine identification of the nerve during thyroidectomy can be a way to prevent injury. Despite recommendation for identification of the RLN peroperatively in thyroid surgery, a debate still exists whether the nerve to be identified peroperatively or not, to avoid its inadvertent injury. The aim of this study was to compare the incidence of RLN injury between two groups where RLN was identified peroperatively in one group and the nerve was not attempted for identification in the other group in thyroid surgery. A comparative cross-sectional study was carried out in the department of surgery and otolaryngology at Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from June 2018 to November 2019, on patients who underwent elective thyroid surgery. Patients were included in RLN identified group and in RLN not identified group, by individual surgeons' preference to identify or not to identify the RLN peroperatively. Peroperative identification of the nerve was done by direct visualization. All cases were evaluated for vocal cord palsy preoperatively, during extubation and postoperatively. Patient's particulars, other parameters and perioperative data were recorded. A total of 80 cases were included in this study, 40 cases (50.0%) in the peroperative RLN identified group and 40 cases (50.0%) in the RLN not identified group. Unilateral RLN palsy was encountered in 2.5% (2 cases) in the RLN identified group and 6.3% (5 cases) in the nerve not identified group (p value 0.192). Transient unilateral RLN palsy was seen in 7.5% (6 cases) of patients; 2.5% (2 cases) in the RLN identified group and 5.0% (4 cases) in the RLN not identified group. And 1.3% (1 case) of permanent unilateral RLN palsy was encountered in this study, which was in the RLN not identified group; there was no permanent palsy in the RLN identified group. We did not encounter any bilateral RLN palsy. There was no statistically significant difference in the incidence of RLN injury between the peroperatively RLN identified group and no attempt to identify the nerve group despite recommendation for peroperative RLN identification in thyroid surgery to avoid its inadvertent injury. However, from this study, we recommend peroperative RLN identification in thyroid surgery to enhance surgical skill.

Complications after radiofrequency ablation of hyperparathyroidism secondary to chronic kidney disease.

OBJECTIVE: To study the complications of ultrasound-guided radiofrequency ablation (RFA) in chronic kidney disease (CKD) patients undergoing renal replacement therapy with secondary hyperparathyroidism (SHPT). METHODS: This retrospective study reviewed the clinical data, including general information, examination results, treatment times, time interval, and postoperative complications, of 103 SHPT patients who received ultrasound-guided RFA treatment from July 2017 to January 2021. RESULTS: Of 103 patients, 52 required two sessions of RFA within a month. The incidence of recurrent laryngeal nerve injury at the second treatment was significantly higher than that at the first treatment (first session vs. second session, 5.77% vs. 21.15%; p = .021). Of all the enrolled 103 patients, 27 suffered complications after the first session of RFA. When we separated patients into complications group and non-complication group, we detected more ablated nodules in the complications group (Z = -2.222; p = .0026). Subgroup analysis further showed that the patients in the severe hypocalcemia group were younger (p = .005), had more ablated nodules (p = .003) and higher blood phosphorus (p = .012) and alkaline phosphatase (ALP) levels (p = .002). Univariate analysis showed that age, serum phosphorus, ALP, and number of ablated nodules were associated with a higher risk of severe hypocalcemia after the first session of RFA. CONCLUSIONS: An interval of more than 1 month between two treatments may help to avoid recurrent laryngeal nerve injury. Age, serum phosphorus, ALP, and number of ablated nodules were associated with a higher risk of severe hypocalcemia after the first session of RFA.

Recurrent Nerve Injury After Total Thyroidectomy: Risk Factor Analysis of a Targeted NSQIP Data Set.

BACKGROUND: Recurrent laryngeal nerve (RLN) injury is a significant complication after thyroidectomy. Understanding risk factors for RLN injury and the associated postoperative complications may help inform quality improvement initiatives. METHODS: The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) thyroidectomy-targeted database was utilized for patients undergoing total thyroidectomy between 2016 and 2017. Univariable and multivariable regression were used to identify factors associated with RLN injury. RESULTS: A total of 6538 patients were identified. The overall rate of RLN injury was 7.1% (467/6538). Of these, 4129 (63.1%) patients had intraoperative neuromonitoring (IONM), with an associated RLN injury rate of 6.5% (versus 8.2% without). African American and Asian race, non-elective surgery, parathyroid auto-transplantation, and lack of RLN monitoring were all significantly associated with nerve injury on multivariable analysis (P<.05). Patients with RLN injury were more likely to experience cardiopulmonary complications, re-intubation, longer length of stay, readmission, and reoperation. Patients who had IONM and sustained RLN injury remained at risk for developing significant postoperative complications, although the extent of cardiopulmonary complications was less severe in this cohort. DISCUSSION: Recurrent laryngeal nerve injury is common after thyroidectomy and is associated with significant morbidity, despite best practices. Attention to preoperative characteristics may help clinicians to further risk stratify patients prior to thyroidectomy. While IONM does not mitigate all complications, use of this technology may decrease severity of postoperative complications.

Incidence of Dysphonia and Dysphagia Exceeds Recurrent Laryngeal Nerve Injury During Thyroid Surgery.

OBJECTIVES: To determine the prevalence of separate and combined voice and swallowing impairments before and after total thyroidectomy and to delineate risk factors for these symptoms. METHODS: Retrospective review of 592 consecutive patients who underwent total thyroidectomy from July 2003 to August 2015. RESULTS: Combined voice and swallowing problems occurred preoperatively in 4.7% (11/234), 3.3% (3/92), and 6.0% (16/266) of patients with malignancy, hyperthyroidism, and benign euthyroid disease, respectively. Postoperatively, prevalence was 5.1%, 2.2%, and 1.9%, respectively. Benign euthyroid disease (20.7%) had the greatest risk of preoperative dysphagia (P = 0.003) and the largest glands (P < 0.001). Comparing before and after surgery, the cancer and benign euthyroid groups had decreased dysphagia (cancer: 11.5% vs. 6.0%, P = 0.034; benign: 20.7% vs. 3.8%, P < 0.001) but increased dysphonia (cancer: 19.2% vs. 28.6%, P = 0.017; benign: 15.8% vs. 27.1%, P = 0.002). Overall, 23/592 (3.9%) developed new dysphagia and 122/592 (20.6%) developed new dysphonia after surgery. Intraoperative recurrent laryngeal nerve transection occurred in 12 cases (2.0%). CONCLUSIONS: Total thyroidectomy resolved dysphagia but increased dysphonia in benign and malignant euthyroid patients. Voice and swallowing problems following thyroidectomy occurred more frequently than intraoperative recurrent laryngeal nerve transection, confirming symptoms often occur in the absence of suspected nerve injury.

Intraoperative Neuromonitoring and Optical Magnification in the Prevention of Recurrent Laryngeal Nerve Injuries during Total Thyroidectomy.

Background and Objectives: Recurrent laryngeal nerve (RLN) paralysis is a fearful complication during thyroidectomy. Intraoperative neuromonitoring (IONM) and optical magnification (OM) facilitate RLN identification and dissection. The purpose of our study was to evaluate the influence of the two techniques on the incidence of RLN paralysis and determine correlations regarding common outcomes in thyroid surgery. Materials and Methods: Two equally sized groups of 50 patients who underwent total thyroidectomies were examined. In the first group (OM), only surgical binocular loupes (2.5×−4.5×) were used during surgery, while in the second group (IONM), the intermittent NIM was applied. Results: Both the operative time and the length of hospitalization were shorter in the OM group than in the IONM group (median 80 versus 100 min and median 2 versus 4 days, respectively) (p < 0.05). The male patients were found to have a five-fold higher risk of developing transient dysphonia than the females (adjusted OR 5.19, 95% IC 0.99−27.18, p = 0.05). The OM group reported a four-fold higher risk of developing transient hypocalcemia than the IONM group (OR 3.78, adjusted OR 4.11, p = 0.01). Despite two cases of temporary bilateral RLN paralysis in the IONM group versus none in the OM group, no statistically significant difference was found (p > 0.05). No permanent RLN paralysis or hypoparathyroidism have been reported. Conclusions: Despite some limitations, our study is the first to compare the use of IONM with OM alone in the prevention of RLN injuries. The risk of recurrent complications remains comparable and both techniques can be considered valid instruments, especially if applied simultaneously by surgeons.

Effect of Intraoperative Neuromonitoring on the Risks of Recurrent Laryngeal Nerve Injury During Thyroidectomy: A Doubly Robust Approach.

OBJECTIVE: To evaluate the relationship between the use intraoperative neuromonitoring (IONM) during thyroidectomy and the risk of recurrent laryngeal nerve (RLN) injury. BACKGROUND: The role of IONM in reducing RLN injury during thyroidectomy remains controversial. Several studies on this topic apply conventional multivariable regression to adjust for confounding. However, estimates from this method may be biased due to model misspecification, especially with a rare outcome such as RLN injury. METHODS: We used a pooled dataset created by linking the 2016-2019 National Surgical Quality Improvement Project General Participant User File with the corresponding Targeted-Thyroidectomy file. The primary outcome was RLN injury rates, and the secondary outcomes were operating time and postoperative length of stay. A doubly robust (DR) estimator, in the form of an inverse-probability-weighted regression adjustment model, was used to estimate the effect of the use of IONM on the risk of RLN injury. Sensitivity analyses was performed. RESULTS: Twenty-four thousand three hundred seventy patients were evaluated, out of which 15,836 (70%) patients had IONM during thyroidectomy, and RLN injury occurred in 1498 (6.2%) cases. Rates of RLN injury increase with increasing age and BMI and are higher in patients with a cancer diagnosis, previous neck operation, total thyroidectomy, and node dissection. Doubly robust model suggests that the use of IONM was associated with a significant reduction in overall rate of RLN injury [risk ratio 0.77, confidence interval (CI), 0.68-0.87, P <0.001], and postoperative length of stay [-2.5 hours (CI, -4.18 to -0.81 h), P =0.004]. However, IONM use was associated with an increase in operating time [15.41 minutes (CI, 13.29-17.54 minutes), P <0.0001]. Sensitivity analyses revealed that our estimates are largely robust to confounding. CONCLUSION: In a balanced cohort of patients undergoing thyroidectomy from multiple sites and surgeons participating in National Surgical Quality Improvement Project, the use of IONM during thyroidectomy was associated with reduction in RLN injury.

Recurrent Laryngeal Nerve Injury in Thermal Ablation of Thyroid Nodules-Risk Factors and Cause Analysis.

CONTEXT: Recurrent laryngeal nerve (RLN) injury is a complication of thermal thyroid nodule treatment. OBJECTIVE: We investigated the influencing factors of RLN injury in patients who underwent thermal ablation of thyroid nodules. METHODS: The data of 1004 patients (252 male, 752 female; median age 44 years) who underwent thermal thyroid nodule ablation were retrospectively reviewed. Patients were divided into benign cystic, benign solid, and papillary thyroid cancer (PTC) groups. The parameters related to RLN injury were analyzed, including the largest diameter, location of the nodules, and shortest distance of the nodule to thyroid capsule and tracheoesophageal groove (TEG). Univariate and multivariate analyses were performed to select risk factors for RLN injury. RESULTS: The RLN injury rate was higher in PTC (6.3%) than in benign cystic (1.2%, P = 0.019) and solid nodules (2.9%, P = 0.018). PTC subgroup analysis showed that the RLN injury rate was higher in T1b (10.7%) and T2 (28.6%) PTC than in T1a PTC (5.0%, P < 0.05). In the PTC group, TEG distance, anterior capsule distance, median capsule distance, posterior capsule distance, and maximum nodule diameter were risk factors for RLN injury. The logistic regression fitting of the nomogram showed high prediction efficiency (C-Index 0.876). The main cause of RLN injury was insufficient medial isolating fluid (MIF). The safety thicknesses of MIF for benign cystic, benign solid, and PTC nodules were 3.1 mm, 3.7 mm, and 3.9 mm, respectively. CONCLUSION: Several risk factors for RLN injury should be considered before thermal ablation of thyroid nodules. The RLN injury rate could be predicted with the nomogram.

Thyroidectomy for Graves' Disease Predicts Postoperative Neck Hematoma and Hypocalcemia: A North American cohort study.

OBJECTIVE: Examine the association of Graves' disease with the development of postoperative neck hematoma. DESIGN: A cohort of patients participating in the Thyroid Procedure-Targeted Database of the National Surgical Quality Improvement Program from January 1, 2016 to December 31, 2018. SETTING: A North American surgical cohort study. METHODS: 17 906 patients who underwent thyroidectomy were included. Propensity score matching was performed to adjust for differences in baseline covariates. Multivariate logistic regression was used to ascertain the association between thyroidectomy for Graves' disease and risk of postoperative adverse events within 30 days of surgery. The primary outcome was postoperative hematoma. Secondary outcomes were postoperative hypocalcemia and recurrent laryngeal nerve injury. RESULTS: One-to-three propensity score matching yielded 1207 patients with mean age (SD) of 42.6 (14.9) years and 1017 (84.3%) female in the group with Graves' disease and 3621 patients with mean age (SD) of 46.7 (15.0%) years and 2998 (82.8%) female in the group with indications other than Graves' disease for thyroidectomy. The cumulative 30-day incidence of postoperative hematoma was 3.1% (38/1207) in the Graves' disease group and 1.9% (70/3621) in other patients. The matched cohort showed that Graves' disease was associated with higher odds of postoperative hematoma (OR 1.65, 95% CI 1.10-2.46) and hypocalcemia (OR 2.04, 95% CI 1.66-2.50) compared with other indications for thyroid surgery. There was no difference in recurrent laryngeal nerve injury among the 2 groups. CONCLUSIONS: Patients with Graves' disease undergoing thyroidectomy are more likely to suffer from postoperative hematoma and hypocalcemia compared to patients undergoing surgery for other indications.

Intraoperative neuromonitoring in thyroidectomy for carcinoma in a high-volume academic hospital.

BACKGROUND: The diagnosis of thyroid carcinoma has changed in last decades, as the surgical technique during thyroidectomy (endoscopic surgery, robotic surgery, new energy device, intraoperative neuromonitoring). METHODS: We analyzed patients undergone to thyroidectomy or lobectomy for thyroid carcinoma from January 2010 to December 2019 at the General Surgery Unit of the Hospital - University of Parma. We divided patients into two groups, based on the use or not of IONM. RESULTS: We analyzed data about 638 patients, 486 (76.2%) females and 152 (23.8%) males, with a mean age of 51.8 years. Totally, 574 patients underwent total thyroidectomy and lymphadenectomy was performed in 39 patients. The lobectomy rate was higher in interventions with neuromonitoring (13.93%) than in those without IONM (3.06%). Considering the incidence of postoperative complications and the presence of infiltration of perithyroid tissues or thyroiditis or lymph node metastasis at the histological report, a statistically significant percentage of dysphonia and paraesthesia was recorded only in patients with infiltration of perithyroid tissues (P<0.0001). There was no significant difference in postoperative blood calcium values. The use of intraoperative neuromonitoring has not significantly changed the incidence of postoperative complication. CONCLUSIONS: Our study did not show a protective impact of the use of intraoperative neuromonitoring during thyroidectomy on the incidence of postoperative complications but confirmed that it increases the surgeon's feel safety during surgery and facilitates the identification of any undetected nerve lesion with visually intact nerve, inducing the interruption of the thyroidectomy after lobectomy alone, reducing the risk of bilateral recurrent paralysis.

Post-thyroidectomy complications in southwestern Saudi Arabia: a retrospective study of a 6-year period.

BACKGROUND: Thyroidectomy is the surgical removal of all or part of the thyroid gland for non-neoplastic and neoplastic thyroid diseases. Major postoperative complications of thyroidectomy, including recurrent laryngeal nerve injury, hypocalcemia, and hypothyroidism, are not infrequent. OBJECTIVE: Summarize the frequency of surgical complications of thyroidectomy. DESIGN: Retrospective. SETTING: Secondary health facility in southwestern Saudi Arabia. PATIENTS AND METHODS: We collected data from the records of patients who were managed for thyroid diseases between December 2013 and December 2019. MAIN OUTCOME MEASURE: Complications following thyroidectomy. SAMPLE SIZE: 339 patients, 280 (82.6%) females and 59 (17.4%) males. RESULTS: We found 311 (91.7%) benign and 28 (8.3%) malignant thyroid disorders. Definitive management included 129 (38.1%) total thyroidectomies, 70 (20.6%) hemithyroidectomies, 10 (2.9%) subtotal thyroidectomies and 5 (1.5%) near-total thyroidectomies with 125 (36.9%) patients treated non-surgically. The overall complication rate was 11.3%. There were 4 (1.9%) patients with recurrent laryngeal nerve palsy, 16 (7.5%) patients with temporary hypoparathyroidism, 1 (0.5%) patient with paralysis of the external branch of the superior laryngeal nerve and 3 (1.4%) patients with wound hematoma. CONCLUSION: The rate of complications following thyroidectomy is still high. There is a need for emphasis on comprehensive measures to control the high rate of complications. LIMITATIONS: Retrospective design and no long-term follow up to monitor late complications. CONFLICT OF INTEREST: None.

Morbidity following thyroid and parathyroid surgery: Results from key performance indicator assessment at a high-volume centre in New Zealand.

BACKGROUND: Complications following thyroid/parathyroid surgery include recurrent laryngeal nerve (RLN) injury, hypocalcaemia and return to theatre for haematoma evacuation. Rates of these form the basis of key performance indicators (KPI). An endocrine database, containing results from 1997, was established at the North Shore Hospital in Auckland, New Zealand. We aimed to measure complication rates by procedure (thyroid and parathyroid), explore a temporal change in our unit and compare our results against international literature. METHODS: A retrospective review of the database between July 1997 and February 2020 was performed. The results for each KPI were analysed in total and over consecutive time periods. A review of the literature was carried out to find international complication rates for comparison. A cumulative sum (CUSUM) analysis was performed to give visual feedback on performance. RESULTS: There were 1062 thyroidectomies and 336 parathyroidectomies from July 1997 to February 2020. Thyroid surgery results found rates of temporary/permanent RLN injury of 1.9%/0.3%, temporary/permanent hypocalcaemia of 22.3/2.5%, and return to theatre for haematoma evacuation of 1.1%. Parathyroid surgery results were, temporary RLN injury of 0.8% (no permanent injury), temporary/permanent hypocalcaemia of 1.7%/0.4%, and return to theatre for haematoma evacuation of 0.3%. CUSUM analysis found KPI results to be comparable with international literature. CONCLUSION: Our unit's KPI results are comparable to published results in the literature. The use of this clinical database will help in future monitoring of performance and help drive improvement in the service. Embedding prospective data collection as routine practice allows for continuous improvement for the unit.

The circumstances in which recurrent laryngeal nerve palsy occurs after surgery for benign thyroid disease: a retrospective study of 1026 patients.

OBJECTIVE: To evaluate the circumstances in which recurrent laryngeal nerve palsy occurs after thyroid surgery. METHODS: This study assessed 1026 patients who underwent surgery for benign thyroid disease over a seven-year period in a retrospective, single-centre study. RESULTS: With a total of 1835 recurrent laryngeal nerves at risk, there were 38 cases (2.07 per cent) of transient recurrent laryngeal nerve palsy and 8 (0.44 per cent) of permanent recurrent laryngeal nerve palsy. No explanation was found for 10 of the 46 cases of recurrent laryngeal nerve palsy. Among the 38 other cases, the probable causes included poor identification of the recurrent laryngeal nerve during surgery, involuntary resection of the nerve and several other factors. CONCLUSION: Apart from accidental resection of the recurrent laryngeal nerve during thyroid surgery, the causes of post-operative recurrent laryngeal nerve palsy are often unclear and likely multifactorial. Poor identification of the recurrent laryngeal nerve during surgery is still the main cause of post-operative recurrent laryngeal nerve palsy, even when intra-operative neuromonitoring is used.

Anatomical and developmental aspects of iatrogenic injury to the right recurrent laryngeal nerve in surgical resections of substernal goiter.

Thyroid surgery is the primary treatment for substernal goiters, and iatrogenic injury to the recurrent laryngeal nerve (RNL) is always a risk. The literature suggests that iatrogenic lesions of the RNL post resection of substernal goiter are not equally distributed, being more frequent on the right recurrent laryngeal nerve (R-RLN) in comparison to the left recurrent laryngeal nerve (L-RLN). The relative paucity of basic anatomical and clinical reportages on R-RLN iatrogenic injuries and on the developmental factors that may help explain its higher incidence justifies this study's undertaking. Here we compare incidence of right versus left iatrogenic injuries to the RLN in surgical resections of substernal goiters and discuss the anatomical and embryological factors involved. This report is part of a larger retrospective observational cohort study of 239 patients surgically treated for substernal goiter in the Gaffrée and Guinle University Hospital, Rio de Janeiro, from 2006 to 2018. From 239 patients, 13 presented with iatrogenic RLN injury, one patient presented bilateral lesion, totalling 15 iatrogenic lesions. Our analysis showed that the R-RLN seems to be anatomically more vulnerable to injury due to the embryological underpinnings addressed in this review, R-RLN = 64.29% (n = 9) and L-RLN = 35.71% (n = 5). Pathological factors like malignancy and size of the mass are relevant issues to be considered. The knowledge of anatomical landmarks and embryological development of the thyroid and associated structures can improve our understanding and teaching of surgical anatomy, thus helping prevent and reduce the number of iatrogenic injuries on right RLNs.

Prophylactic Central Neck Dissection in Papillary Thyroid Carcinoma: All Risks, No Reward.

BACKGROUND: Central neck dissection (CND) remains a controversial intervention for papillary thyroid carcinoma (PTC) patients with clinically negative nodes (cN0) in the central compartment. Proponents state that CND in cN0 patients prevents locoregional recurrence, while opponents deem that the risks of complications outweigh any potential benefit. Thus, there remains conflicting results amongst studies assessing oncologic and surgical outcomes in cN0 PTC patients who undergo CND. To provide clarity to this controversy, we sought to evaluate the efficacy, safety, and oncologic impact of CND in cN0 PTC patients at our institution. MATERIALS AND METHODS: Six hundred and ninety-five patients with PTC who underwent thyroidectomy at our institution between 1998 and 2018 were identified using an institutional cancer registry and supplemental electronic medical record queries. Patients were stratified by whether or not they underwent CND; identified as CND(+) or CND(-), respectively. Patients were also stratified by whether or not they received adjuvant radioactive iodine (RAI) therapy. Patient demographics, pathologic results, as well as surgical and oncologic outcomes were reviewed. Standard statistical analyses were performed using ANOVA and/or t-test and chi-squared tests as appropriate. RESULTS: Among the 695 patients with PTC, 492 (70.8%) had clinically and radiographically node negative disease (cN0). The mean age was 50 ± 1 years old and 368 (74.8%) were female. Of those with cN0 PTC, 61 patients (12.4%) underwent CND. CND(+) patients were found to have higher preoperative thyroid stimulating hormone (TSH) values, 2.8 ± 0.8 versus 1.5 ± 0.2 mU/L (P = 0.028) compared to CND(-) patients. CND did not significantly decrease disease recurrence, development of distant metastatic disease (P = 0.105) or persistence of disease (P = 0.069) at time of mean follow-up of 38 ± 3 months compared to CND(-) patients. However, surgical morbidity rates were significantly higher in CND(+) patients; including transient hypocalcemia (36.1% versus 14.4%; P < 0.001), transient recurrent laryngeal nerve (RLN) injury (19.7% vers us 7.0%; P < 0.001), and permanent RLN injury (3.3% versus 0.7%; P < 0.001). CONCLUSIONS: The majority of patients at our institution with cN0 PTC did not undergo CND. This data suggests that CND was not associated with improvements in oncologic outcomes during the short-term follow-up period and led to increased postoperative morbidity. Therefore, we conclude that CND should not be routinely performed for patients with cN0 PTC.

Intraoperative nerve monitoring in thyroid surgery: analysis of United Kingdom registry of endocrine and thyroid surgery database.

BACKGROUND: Intraoperative nerve monitoring (IONM) is used increasingly in thyroid surgery to prevent recurrent laryngeal nerve (RLN) injury, despite lack of definitive evidence. This study analysed the United Kingdom Registry of Endocrine and Thyroid Surgery (UKRETS) to investigate whether IONM reduced the incidence of RLN injury. METHODS: UKRETS data were extracted on 28 July 2018. Factors related to risk of RLN palsy, such as age, sex, retrosternal goitre, reoperation, use of energy devices, extent of surgery, nodal dissection and IONM, were analysed. Data with missing entries for these risk factors were excluded. Outcomes of patients who had preoperative and postoperative laryngoscopy were analysed. RESULTS: RLN palsy occurred in 4.9 per cent of thyroidectomies. The palsy was temporary in 64.6 per cent and persistent in 35.4 per cent of patients. In multivariable analysis, IONM reduced the risk of RLN palsy (odds ratio (OR) 0.63, 95 per cent confidence interval (CI) 0.54 to 0.74, P < 0.001) and persistent nerve palsy (OR 0.47, 0.37 to 0.61, P < 0.001). Outpatient laryngoscopy was also associated with a reduced incidence of RLN palsy (OR 0.50, 0.37 to 0.67, P < 0.001). Bilateral RLN palsy occurred in 0.3 per cent. Reoperation (OR 12.30, 2.90 to 52.10, P = 0.001) and total thyroidectomy (OR 6.52, 1.50 to 27.80; P = 0.010) were significantly associated with bilateral RLN palsy. CONCLUSION: The use of IONM is associated with a decreased risk of RLN injury in thyroidectomy. These results based on analysis of UKRETS data support the routine use of RLN monitoring in thyroid surgery.

An Institutional experience with primary hyperparathyroidism in the elderly over two decades.

BACKGROUND: Parathyroidectomy is the only curative treatment for primary hyperparathyroidism (pHPT) and is associated with low morbidity. This study examined the severity of disease and outcomes of parathyroidectomy based on patient age at a high-volume institution. METHODS: This is a retrospective review of sporadic pHPT patients who underwent initial parathyroidectomy. To study disease severity over time, patients were divided into timeframes: 1999-2007, 2007-2012, and 2013-2018. Elderly was defined as age ≥75 years. RESULTS: Over time, the elderly had progressively lower preoperative calcium (11.0, 10.7, 10.7; p = 0.05) and PTH (150.4, 111.9, 107.9; p < 0.001) levels. By age, there was no difference in preoperative calcium (10.8, 10.9; p = 0.91) or in rates of recurrent laryngeal nerve injury, hypoparathyroidism, or persistent/recurrent pHPT. CONCLUSIONS: Over the 3 time periods of the study, elderly patients had progressively lower calcium and PTH levels. There was no difference in endocrine-specific complications between the age groups, suggesting that parathyroidectomy in the elderly is safe and therefore, age-associated morbidity should not preclude parathyroidectomy.

Warning criterion to predict recurrent laryngeal nerve injury with percentage reduction of the amplitude of V2/R2d in neuromonitoring thyroidectomy.

OBJECTIVE: To evaluate the contribution of amplitude reduction compared vagal stimulation at the end of thyroid dissection (V2) to the most distal RLN stimulation during thyroidectomy in predicting postoperative vocal cords paralysis (VCP). METHODS: Patients with intact preoperative RLN function who underwent monitored thyroidectomy between August 2017 and April 2018 were included. We routinely tested the exposed RLN at the lowest proximal end (R2p signal) and the most distal end near the laryngeal entry point (R2d signal), and then routinely detected the vagal nerve at the horizontal plane of the inferior pole of thyroid with 2mA stimulation current. The cut-off value was calculated with Receiver Operating Characteristic curve. Rates of specificity, sensitivity, negative predictive value, positive predictive value (PPV) for V2/R2d and R2p/R2d were compared. RESULTS: Percentage reduction of the amplitude of V2/R2d ranged from 34.8% to 76.7%. Twenty-two (1.5%) nerves developed temporary VCP, in which one nerve with VCP showed no significant amplitude reduction at the end of the surgery. There was no permanent or bilateral VCP. Sensitivity, specificity, PPV, NPV, and accuracy for the amplitude reduction of V2/R2d> 60% were 95.5%, 99.8%, 99.9%, 98.2%, respectively, for R2p/R2d were 99.5%, 99.2%, 63.6%, 99.9%, 97.7%, respectively. CONCLUSION: Percentage reduction of the amplitude of V2/R2d is a reliable and practical warning criterion for RLN injury. When the amplitude reduction> 60% surgeons should consider the possibility of postoperative VCP and correct some surgical maneuvers.

Intraoperative neuromonitoring during prone thoracoscopic esophagectomy for esophageal cancer reduces the incidence of recurrent laryngeal nerve palsy: a single-center study.

The incidence of recurrent laryngeal nerve palsy (RLNP) following minimally invasive esophagectomy has yet to be satisfactorily reduced. Use of intraoperative neuromonitoring (IONM), specifically of the RLN, during thyroidectomy has been reported to reduce the incidence of RLN injury. We now apply IONM during curative prone thoracoscopic esophagectomy, and we conducted a retrospective study to evaluate the feasibility and efficacy of intermittent monitoring of the RLN during the surgery. The study involved 32 consecutive patients who underwent esophagectomy with radical lymph node dissection for esophageal cancer. The patients were of two groups: an IONM group (n = 17) and a non-IONM group (n = 15). We chiefly strip around the esophagus preserving the membranous structure, which contains the tracheoesophageal artery, lymph nodes, and RLN. In the IONM group patients, we stimulated the RLN and measured the electromyography (EMG) amplitude after dissection, at the dissection starting point and dissection end point on both sides. For the purpose of the study, we compared outcomes between the two groups of patients. IONM was carried out successfully in all 17 patients in the IONM group. The incidence of RLNP was significantly reduced in this group. We found that both RLNs can be identified by mean of IONM easily, immediately, and safely and that the EMG amplitude attenuation rate is particularly useful for predicting RLNP.