Course Of Recurrent Laryngeal Nerve Research Articles

Recurrent laryngeal nerve’s course running anteriorly to a thyroid tumor

The thyroid gland's neurovascular relationship is commonly portrayed as the recurrent laryngeal nerve (RLN) coursing posteriorly to the thyroid gland. We report a rare case with the RLN running anteriorly to a thyroid tumor. A 56-year-old Japanese woman underwent a thyroidectomy for a benign thyroid tumor. Preoperatively, computed tomography confirmed that part of the tumor had extended into the mediastinum and was descending posteriorly up to the brachiocephalic artery. Intraoperatively, when the sternothyroid muscle was incised to expose the thyroid gland, a cord (nerve)-like structure was observed directly anterior to the thyroid tumor. Although the course of this cord-like structure was clearly different from the "traditional" course of the right RLN, the possibility that the structure was the RLN could not be excluded. The structure was traced back in order to preserve it; we saw that it entered the larynx at the lower margin of the cricothyroid muscle and approximately at the level of the cricothyroid junction through the back of the normal thyroid tissue. With intraoperative neuromonitoring, the structure was identified as the RLN. As a result, the course of the RLN run anterior to the tumor but then posterior to the 'normal thyroid' i.e. into it normal anatomical position. Had we assumed that the RLN was behind the thyroid tumor, we would have damaged the RLN. It would not be possible to diagnose this abnormal running course of the RLN reliably before surgery, but extra care should be taken in similar cases, that is, when a large thyroid tumor is descending posteriorly up to the brachiocephalic artery on the right side.

When The Silence Prevails, Images Talk: The Characteristic Ct Features Of Vocal Cord Paralysis, Causes Of Missed Palsy By Radiologists And Mimics Of Vocal Cord Palsy Unveiled.

Causes of vocal cord palsy (VCP) can be identified even before its clinical presentation if a radiologist has knowledge about signs of vocal cord palsy, its various mimics and the anatomy of recurrent laryngeal nerve. Objectives are to know the signs and underlying causes leading to VCP and various mimics which may lead to the false positive diagnosis of VCP. A retrospective cross-sectional pilot study comprising 54 patients with vocal cord palsy proven by IDL was conducted. 3 groups were identified. The first group comprised missed VCP on cross-sectional imaging. The second group was, of missed cause of VCP in patients with clinical diagnoses. The third group was patients with mimics of the palsy. Thirteen (76.5%) patients had missed diagnosis due to lack of knowledge of signs and 23.5% due to lack of time, overwork and tiredness. A vigilant search for the cause was not done in 31.6% of patients and in 68.4% of patients, the cause was identified but not correlated. A total of 8 patients had false positive diagnoses due to failure to differentiate from mimics. There is an increasing trend of missed diagnosis of vocal cord palsy on cross-sectional imaging in patients with established clinical diagnosis due to a lack of knowledge of VCP signs and missed causes along the course of recurrent laryngeal nerve.

Double Right Recurrent Laryngeal Nerve: Intraoperative Identification

Recurrent laryngeal nerves are located lateral to the ligament of Berry and behind the tubercle of Zuckerland where they enter the larynx bilaterally. Various anatomical alteration in course of recurrent laryngeal nerves has been reported including non-recurrent course.

Invasion of a Recurrent Laryngeal Nerve from Small Well-Differentiated Papillary Thyroid Cancers: Patient Selection Implications for Active Surveillance.

Background: The success of an active surveillance management approach to low-risk papillary thyroid cancer (PTC) is heavily dependent on proper patient selection. For example, primary tumors located in a subcapsular position immediately adjacent to the trachea or a recurrent laryngeal nerve (RLN) are considered to be inappropriate for active surveillance. Since preoperative imaging cannot reliably rule out extrathyroidal extension or reveal the full course of the RLN relative to the thyroid gland, it is important for clinicians to understand subcapsular tumor locations and minimum tumor sizes that are most likely to be associated with gross invasion of the RLNs. Methods: We assessed the medical records of 123 patients treated at Memorial Sloan Kettering Cancer Center (MSK) between 1986 and 2015 who had a primary PTC tumor demonstrating gross extrathyroidal extension to either the right or left RLN. Thirty patients with a primary tumor ≤2 cm in diameter demonstrating extrathyroidal extension into an RLN were included in the analysis. Results: Gross invasion of an RLN by tumors ≤2 cm is a rare event that was seen in only 0.8% (35/4334) of patients with PTC who underwent initial thyroid surgery at MSK between 1986 and 2015. Gross RLN invasion was associated with subcapsular PTC tumors located in either the right paratracheal area (60%), left paratracheal area (36.7%), or right lateral posterior lobe area not adjacent to the trachea (3.3%). Only a quarter of the patients had imaging findings suggestive of extrathyroidal extension and only 30% had clinically apparent vocal paresis/paralysis on preoperative examination. Invasion of the RLN was not observed for primary tumors <0.9 cm in diameter, regardless of tumor location. Conclusions: Well-differentiated PTC tumors ≥0.9 cm in maximal diameter that are located in the right paratracheal, left paratracheal, and right lateral posterior lobe subcapsular positions are usually not appropriate for active surveillance even in the absence of definitive evidence for nerve invasion on preoperative imaging or vocal cord examination. Patient selection for active surveillance management should take into account not only the size and growth rate of a tumor but also its location in relation to the expected course of RLNs.

Varied Recurrent Laryngeal Nerve Course Is Associated with Increased Risk of Nerve Dysfunction During Thyroidectomy: Results of the Surgical Anatomy of the Recurrent Laryngeal Nerve in Thyroid Surgery Study, an International Multicenter Prospective Anatomic and Electrophysiologic Study of 1000 Monitored Nerves at Risk from the International Neural Monitoring Study Group

Background: The recurrent laryngeal nerve (RLN) can be injured during thyroid surgery, which can negatively affect a patient's quality of life. The impact of intraoperative anatomic variations of the RLN on nerve injury remains unclear. Objectives of this study were to (1) better understand the detailed surgical anatomic variability of the RLN with a worldwide perspective; (2) establish potential correlates between intraoperative RLN anatomy and electrophysiologic responses; and (3) use the information to minimize complications and assure accurate and safe intraoperative neuromonitoring (IONM). Methods: A large international registry database study with prospectively collected data was conducted through the International Neural Monitoring Study Group (INMSG) evaluating 1000 RLNs at risk during thyroid surgery using a specially designed online data repository. Monitored thyroid surgeries following standardized IONM guidelines were included. Cases with bulky lymphadenopathy, IONM failure, and failed RLN visualization were excluded. Systematic evaluation of the surgical anatomy of the RLN was performed using the International RLN Anatomic Classification System. In cases of loss of signal (LOS), the mechanism of neural injury was identified, and functional evaluation of the vocal cord was performed. Results: A total of 1000 nerves at risk (NARs) were evaluated from 574 patients undergoing thyroid surgery at 17 centers from 12 countries and 5 continents. A higher than expected percentage of nerves followed an abnormal intraoperative trajectory (23%). LOS was identified in 3.5% of NARs, with 34% of LOS nerves following an abnormal intraoperative trajectory. LOS was more likely in cases of abnormal nerve trajectory, fixed splayed or entrapped nerves (including at the ligament of Berry), extensive neural dissection, cases of cancer invasion, or when lateral lymph node dissection was needed. Traction injury was found to be the most common form of RLN injury and to be less recoverable than previous reports. Conclusions: Multicenter international studies enrolling diverse patient populations can help reshape our understanding of surgical anatomy during thyroid surgery. There can be significant variability in the anatomic and intraoperative characteristics of the RLN, which can impact the risk of neural injury.

English

BACKGROUND From the last century to modern days, there has been a paradigm shift in the field of thyroid surgery. Initially what was a dreadful surgery with multi fold serious complications, now with the advent of modern surgical technique (bipolar to nerve monitoring &amp; emerging use of microscope), and better knowledge of anatomy, it has become one of the most frequently performed surgeries worldwide with very few complications. In spite of all these, postoperative complications like recurrent laryngeal nerve (RLN) palsy is still mostly feared by surgeons and still is one of the most frequent complications. METHODS This was a prospective nonrandomised controlled trial conducted among 60 study participants in the Department of Otorhinolaryngology and Head &amp; Neck Surgery, of a tertiary care centre in West Bengal from July 2016 to June 2018. In this study two different surgical techniques were applied in two patient groups. In one group subcapsular dissection of thyroid gland was done without exploration of recurrent laryngeal nerve course in neck; and in another group, the complete course of the aforesaid nerve in the neck was explored and preserved. The postoperative functional status of RLN was assessed by fibreoptic laryngoscopy immediately after recovery from anaesthesia and in postoperative follow ups. We wanted to compare the outcome (in terms of functional status of RLN) in these two groups. RESULTS 3 patients (10 % cases) of nerve palsy were seen among 30 patients of subcapsular dissection group, whereas only one case (3.3 %) of nerve palsy was seen amongst 30 cases of complete exploration of recurrent laryngeal nerve. CONCLUSIONS Thyroidectomy with meticulous exploration of the recurrent laryngeal nerve was found to be a superior method as compared to the subcapsular dissection. KEYWORDS Recurrent Laryngeal Nerve, Subcapsular Dissection, Complete Exploration, Thyroidectomy

A novel Killian\u2013Jamieson diverticulectomy using a thyroid gland flap: a case report

BackgroundA Killian–Jamieson diverticulum is a rare pharyngoesophageal diverticulum that is radically treated by diverticulectomy. However, there is no consensus on whether cricopharyngeal myotomy is necessary, and the optimal surgical methods that prevent postoperative complications such as leakage are undetermined.Case presentationA 49-year-old man was referred to our hospital with oropharyngeal dysphagia while eating. The patient was preoperatively diagnosed with a Killian–Jamieson diverticulum based on radiographic and clinical findings and underwent a transcervical diverticulectomy. The recurrent laryngeal nerves were preserved using an intraoperative nerve monitoring system, and the diverticulum was identified without difficulty. A partial cricopharyngeal myotomy was performed to expose the base of the diverticulum. The diverticulum was transected transversally using a linear stapler under the guidance of intraoperative upper intestinal endoscopy. A thyroid gland flap supplied by the superior thyroid artery was harvested and placed overlapping the area of the partial cricopharyngeal myotomy. Due to the proximity of the recurrent laryngeal nerve course to the diverticulum stump, the staple line was not buried with sutures. The thyroid gland flap with its rich vascular supply was fixed to completely cover the staple line on the cut surface of the thyroid gland. The postoperative course was uneventful, without vocal cord paralysis. The patient was discharged on postoperative day 8. He developed no clinical signs suggesting leakage, recurrence, or adverse events.ConclusionKillian–Jamieson diverticulectomy using a thyroid gland flap and partial cricopharyngeal myotomy is a valid treatment option that may prevent complications and recurrence. Precise evaluation of the diverticulum using an intraoperative nerve monitoring system is crucial for the repair.

Recurrent laryngeal nerve management in transoral endoscopic thyroidectomy.

The mechanism of recurrent laryngeal nerve (RLN) injury was investigated during a TransOral Endoscopic Thyroidectomy Vestibular Approach (TOETVA). The function of 185 nerves at risk (NAR) was recorded with intermitted intraoperative neural monitoring (I-IONM). The RLN electromyography (EMG) was delineated during: (a) a pre-dissection vagal nerve stimulation; (b) a RLN stimulation at initial visualization; (c) at nerve dissection; and (d) at the final verification of the entire RLN route. The location, genesis, segmental or diffuse and the outcomes of RLN injuries were catalogued. Twelve nerves (6.4%) lost the EMG signal and the incidences of temporary and permanent RLN dysfunction were 5.9% and 0.5%. A disrupted point (type 1 injury) could be identified in 7/12 nerves (58%). Five (42%) nerve injuries were classified as global (type 2). Of the seven type 1 injuries, 3 lesions occurred at the RLN laryngeal entry point during the nerve identification. Four type 1 injuries were at the distal 1cm of the RLN course and during the early nerve dissection. No proximal (>2cm) injuries occurred. The mechanisms of the injuries were thermal (58%) during the energy-based device use at the ligament of Berry dissection or at the dividing small branches of the inferior thyroid artery. Two (16%) traction injuries occurred during the early nerve dissection. In 2 cases we could not elucidate the mechanism of RLN injury (16%) and 1 injury (8%) was caused by the connective tissue constricting band of. The thermal RLN lesions had longer recovery times. The RLN palsy occurs in TOETVA, even when combined with an endoscopic magnification, IONM, early nerve identification, cranial to caudal dissection and top-down view. The thermal RLN injury was the most frequent cause and all injuries occurred at the distal RLN course.

Tracheoesophageal groove: a reliable landmark

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; Galen first described the recurrent laryngeal nerve (RLN) as a nerve that descended from the brain to the heart, then reversed the course and ascended to the larynx and caused the vocal cords to move. Tracheoesophageal groove is useful for identifying the RLN. In the present study we studied the course of RLN in tracheoesophageal groove and its anatomical position, in patients undergoing thyroid surgery.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; The study was conducted in the Department of ENT and Head and Neck Surgery, SMGS Hospital, for a period of two years, on the patients who underwent thyroid surgeries. Tracheoesophageal groove was considered first landmark to identify RLN position and only after meticulous dissection in the groove, the nerve could be identified. The nerve was carefully dissected and its position evaluated in relation with trachea and esophagus. &lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results:&lt;/strong&gt; Trajectory of the nerves studied in the patients was mostly in the tracheoesophageal groove (TEG), seen in 113 (69.75%) nerves. 16.05% of the nerves were seen in the posterior half of the trachea while 4.94% of the nerves were seen to travel from TEG to anterior half of trachea and 1.85% from TEG to posterior half of trachea. 6.17% of nerves travelled from oesophagus to the TEG.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; A uniform dissection procedure should be followed and the recurrent laryngeal nerve must be first looked for in the TEG, which serves as important landmark and later any deviation must be considered.&lt;/p&gt;&lt;p class="abstract"&gt; &lt;/p&gt;

Immediate Surgery Might Be a Better Option for Subcapsular Thyroid Microcarcinomas.

For high-risk papillary thyroid microcarcinomas (PTMCs), immediate surgery is recommended. This study aimed to evaluate the location of PTMCs in the thyroid lobe and determine whether location is associated with an aggressive biology and the necessity of immediate surgery. This retrospective study included 288 patients who underwent initial surgery for PTMC. Clinical data were extracted. Subcapsular thyroid microcarcinomas (STMs) and nonsubcapsular thyroid microcarcinomas (NSTMs), distinguished by ultrasound, were compared in terms of tumour size, extrathyroidal extension, cervical lymph node metastasis, and multifocality. The preoperative ultrasound features predictive of recurrent laryngeal nerve (RLN) involvement were assessed. There were no statistical differences in tumour size (P = 0.985), multifocality (P = 0.866), lymph node metastases to the central compartment (P = 0.154), or lateral lymph node metastases (P = 0.929) between STM and NSTM groups. Macroscopic extrathyroidal extension was exclusively found in the STM group. For assessing RLN involvement, the sensitivity, specificity, and positive predictive value of the presence of an abnormal thyroid capsule margin between the STM and the presumed RLN course, assessed on preoperative ultrasonography images, were 100%, 43.3%, and 43.3%, respectively. Immediate surgery appears to be a better option than conservative treatment for these high-risk STM patients.

Unilateral vocal cord palsy as the presentation of metastatic mediastinal adenocarcinoma

Introduction: Unilateral vocal cord palsy is more common than the bilateral cases. The left side is more affected than the right side owing the longer course of the Left recurrent laryngeal nerve. Iatrogenic causes for example thyroidectomy or cardiac surgery predominate the etiology of its incidence.Methods: A review of medical case record.Results: A 68-year-old man presented with voice change for one month duration. It was associated with occasional shortness of breath. Examination showed unilateral Left vocal cord palsy. Further investigation revealed a huge anterior mediastinal mass. A CT-guided biopsy was performed and histopathologically confirmed as adenocarcinoma.Conclusion: Any lesion in the course of recurrent laryngeal nerve can lead to vocal cord palsy and change of voice. A metastatic lesion to mediastinal nodes even though very rare can be one of them. Mediastinal lymphoma is one of its differential diagnoses.Bangladesh Journal of Medical Science Vol.17(1) 2018 p.172-174

Etiological Factors and Management of Vocal Fold Paralysis: Single Institution Study

Vocal fold paralysis is a sign of underlying diseases. However, etiologies of this problem are varied and changing from center to center and need more clarification. The aim of the study is to determine the etiological factors and management options of vocal fold paralysis among patients attended to the voice clinic center at King Abdul-Aziz Medical City. The medical records of 106 patients diagnosed with vocal fold paralysis were studied retrospectively. The following variables were recorded; age, gender, occupation, smoking, surgical history, radiation history, cause and type of vocal fold paralysis, associated risks, and management. Out of the 106 cases, 58 were males and 48 females with a ratio of 1.2:1. The age of the patients ranged from 6-92 years. Surgical trauma (iatrogenic) was the leading cause of vocal fold paralysis (45.3%) followed by idiopathic (17.9%), external neck trauma (13.2), Non-laryngeal malignancy (6.6%), post upper respiratory tract infection and viral infection (5.7%), TB and TB lymphadenitis (3.8%), intubation (2.8%), neurogenic (1.8%) and thyroid mass (1.8%). Total thyroidectomy was the most common surgical etiology of vocal fold paralysis (38.8%). The most common etiology of vocal fold paralysis is surgery and most cases were total thyroidectomy. Otolaryngologists should be familiar with the etiology, incidence, evaluation, and management options of vocal fold paralysis to optimize patient care and avoid further complication. We recommend that all patients undergoing total thyroidectomy and surgeries related to the course of recurrent laryngeal nerves should have detailed voice assessment pre-and postoperatively.

Case report: An unusual variation in the course of recurrent laryngeal nerve in relation to the thyroid gland

A complete understanding of the anatomic variations of the thyroid gland is necessary for a safe thyroid surgery. Injury to recurrent laryngeal nerve during thyroid surgery remains a significant source of morbidity. We present an uncommon variation in the position of right recurrent laryngeal nerve with the Tubercle of Zuckerkandl in a 40-year-old female who underwent thyroidectomy for a benign multinodular goiter. Identification and meticulous dissection of the Tubercle of Zuckerkandl and recognition of its association with the recurrent laryngeal nerve are essential to maintain the integrity of the nerve and prevent complications during thyroid surgery.

The Impact of Thyroiditis on Morbidity and Safety in Patients Undergoing Total Thyroidectomy.

Background:The indications for surgery in thyroiditis vary from compressive symptoms to cosmesis. We analyzed the complications in patients who underwent total thyroidectomy (TT) in goiters associated with thyroiditis.Materials and Methods:This retrospective study was done in an endocrine surgical center over 4 years. A total of 724 patients, who underwent TT for benign thyroid disorders, were included in the study. Patients were divided into two groups based on histopathology into Group A (nonthyroiditis cases) and Group B (thyroiditis cases); Group B is subdivided into Group B1 (nodular goiter with associated thyroiditis) and Group B2 (Hashimoto's thyroiditis). The preoperative parameters analyzed were serum calcium, serum Vitamin D, serum parathyroid hormone (PTH), and vocal cord status. The intraoperative parameters observed were operating time, parathyroid preservation, and autotransplantation and course of recurrent laryngeal nerve (RLN). Postoperative parameters monitored were serum calcium, serum PTH, serum magnesium, signs and symptoms of hypocalcemia, and vocal cord status. Follow-up was done at 6 months with serum calcium, serum PTH, and video laryngoscopy.Results:Both groups were age and sex matched. All preoperative and intraoperative parameters were comparable among groups. Both transient complications (<6 months) were higher in Group B than A. Transient hypocalcemia was higher in Group B (39.70%) than Group A (24.77%) (P = 0.001). Transient hypocalcemia was higher in Group B1 (36.58%) than Group B2 (44.44%) (P = 0.014). Transient RLN palsy was higher in Group B (9.55%) than Group A (7.52%) (P = 0.040). Transient RLN palsy was higher in Group B1 (8.53%) than Group B2 (11.11%) (P = 0.039). Permanent hypoparathyroidism and permanent RLN palsy were comparable between the Groups A and B and between Groups B1 and B2.Conclusion:The incidences of transient complications are higher in patients with thyroiditis. Careful analysis of surgical indications will avoid unnecessary surgery in thyroiditis cases.

Thyroid reoperation using intraoperative neuromonitoring

PurposeThyroid reoperations are at a high risk of recurrent laryngeal nerve (RLN) injury. The aim of the study was to investigate whether the use of intraoperative neuromonitoring (IONM) can aid in the RLN identification and minimize the risk of its injury, in comparison with visual RLN identification.MethodsThis was a retrospective cohort study of patients who underwent thyroid reoperations with and without the use of IONM. Primary endpoint was the RLN identification rate; secondary: the prevalence of RLN injury, the frequency of total thyroidectomies, and the course of the RLN.ResultsThe study involved 61 patients undergoing thyroid reoperation among whom 24 were operated on with visual RLN identification only, while 37 procedures used IONM. In the non-monitored reoperations, 44.4% of the RLN were visually identified, as opposed to 91.6% in the IONM group (p < 0.001). Transient paresis occurred in three nerves with visualization (6.6%), and in one in IONM group 1.6% (p = 0.185). Permanent paresis occurred in the group with visualization (6.6%), as opposed to none with neuromonitoring. The extent of resection in both groups was significantly different (p = 0.043). Total, near-total thyroidectomies, Dunhill operations and subtotal thyroidectomies were performed in 71, 17, 4, and 8% in the visualization group, and in 94, 0, 3, and 3%, respectively, in the IONM group. A non-anatomical RLN course was observed in 80% of the reoperations with IONM.ConclusionsThyroid reoperation should be performed using IONM, because it allows for a significantly improved RLN identification rate and a significantly more radical resection.

Large fusiform aortic aneurysm with mural thrombus – a rare cause of hoarseness of voice

Vocal cord paralysis can be caused by any intrinsic or extrinsic cause in the course of recurrent laryngeal nerve. There may be some cardiopulmonary causes such as severe pulmonary hypertension, congenital heart diseases (patent ductus arteriosus), mitral valve disorders, atrial myxoma, iatrogenic (radical neck and mediastinal surgery), malignant neoplasms (lung, esophagus, thyroid, metastatic), inflammatory conditions (tuberculosis), and idiopathic. The present case has an aortic aneurysm which resulted in hoarseness of voice without any cardiopulmonary symptomatology of aneurysm. This rare case of aortic aneurysm with hoarseness without any cardiopulmonary signs and symptoms is not well mentioned in literature. So, the case is being presented because of its rarity.

Berry's Ligament and the Inferior Thyroid Artery as reliable anatomical landmarks for the Recurrent Laryngeal Nerve (RLN): a fresh-cadaveric study of the cervical spine. The RLN relevant to spine

Background ContextAlthough most cadaveric studies of the Recurrent Laryngeal Nerve (RLN) have focused on course variations, they have usually been done on preserved (fixed and embalmed) cadavers, which renders the RLN immobile and of less surgical landmark value. PurposeOur aim was to perform a thorough exposure in fresh cadavers, with the intention of investigating the Inferior Thyroid Artery (ITA) and Berry's ligament as reliable landmarks for the identification of the RLN in anterior cervical spine surgery. Study Design/SettingEight fresh cadavers had layer by layer dissections by two surgeons (one with extensive experience as anatomy dissector) from C2 to T2–T3, with particular attention to illustrating the surgical anatomy of the RLN pertinent to spine. MethodsWe exposed, traced, and referenced the position of RLNs along their entire length bilaterally and examined the reliability of using ITA and superficial fascia of Berry's Ligament as landmark. ResultsIn all specimens, we were able to verify the entire course of RLNs on both the right and left sides in all cadavers dissected in detail from origin to insertion. The RLNs were consistently associated with the ITA and Berry's ligament bilaterally, with the RLNs passing almost perpendicular to these structures. ConclusionsWe found that the most reliable anatomical landmark for the RLN bilaterally was the ITA and Berry's ligament, both of which would be encountered as readily identifiable structures in anterior cervical spinal exposure before the nerve itself. We believe this will help spinal surgeons to refine their surgical technique to identify RLN where necessary, thus preventing iatrogenic injury. Our landmark protocol of FEEL-LOOK-AVOID can serve as an easy aide-mémoire for intraoperative surgical anatomy of the RLN during ACDF regardless of side.

The preoperative evaluation prevent the postoperative complications of thyroidectomy.

ObjectiveThyroid surgery is generally a safe surgery but its complications are still common. We wish to identify preoperative factors that predict postoperative complications.MethodsA nationwide survey was conducted by senior surgeons from 16 medical centers and 5 regional hospitals in Taiwan to thyroid operations performed over 3 years. 3846 cases were retrospectively examined to identify factors influencing complications: indication for surgery, preoperative evaluation, such as ultrasonography, chest X-ray, computed tomography and magnetic resonance imaging, isotope scanning, fine-needle aspiration cytology (FNAC) and thyroid function test, and patient characteristics.ResultsEighty-four percent of patients were female. Seven percent of the patients had immediate postoperative hypocalcemia (mild and severe) and 2.3%, hoarseness (recurrent laryngeal nerve (RLN) injury, temporary/permanent). Logistic regression analysis identified an association between hypocalcemia and RLN injury with age, hospital category, surgical procedure types (total thyroidectomy, unilateral, bilateral subtotal or total resection). A lower incidence of hypocalcemia was related to preoperative neck ultrasound and FNAC analysis (the odds ratio (OR) = 0.5 and 0.65, [95% confidence interval (CI) 0.331–0.768 and 0.459–0.911], P = 0.0014 and 0.0127, respectively), while RLN injury was not associated with any preoperative evaluation. The ORs of hypocalcemia and RLN injury for patients older than 50 years were 0.55 and 2.15, [0.393–0.763 and 1.356–3.4], P < 0.001 and 0.0012, respectively.ConclusionsThe success of thyroid surgery depends on careful preoperative planning, including a preoperative neck ultrasound to determine the proximity of the nodule to the recurrent laryngeal nerve course, and the consideration of the type of anesthesia, adjuvant devices for intra-op monitoring of the RLN, and surgical modalities. Our results suggest that preoperative evaluation implementations are positively associated with strategy of surgery and postoperative hypocalcemia prevention.

Routine computed tomography in the evaluation of vocal fold movement impairment without an apparent cause.

Routine computed tomography (CT) for vocal fold movement impairment (VFMI) without an apparent cause is common. However, given increased cancer risk associated with ionizing radiation exposure, our purpose is to evaluate the utility of routine scans for these patients. Retrospective case series. Houston, Texas. A 5-year review of patients with VFMI diagnosed at an academic institution was conducted. For patients without an apparent cause (eg, recent head, neck, or cardiothoracic surgery or known malignancy), CT head/neck and chest was performed to evaluate the recurrent laryngeal nerve course. Data included demographics, symptoms, radiography, and interventions. Statistical analyses were performed via χ(2) analysis. Of 406 patients with VFMI, 47 (11%) patients had no apparent cause clinically. Routine CT revealed abnormalities in 10 (21%) patients, of which only 3 (6%) could account for VFMI: benign thyroid adenoma (1), papillary thyroid cancer (1), and an esophageal mass (1). The most common lesion detected involved the thyroid. Demographic data and symptom type were not significantly associated with detection of a VFMI-attributable lesion on CT. Overall, routine CT did not identify a focal etiology in 94% patients with VFMI without an apparent cause. Routine pan-CT evaluation failed to reveal an etiology in 94% of patients with VFMI without an apparent cause. Patients may be subjected to health risks associated with radiation exposure without significant diagnostic benefit. Further studies should consider more judicious use of CT in the context of risk factors and safer imaging modalities as the initial diagnostic step.

Surgical anatomy of bilateral extralaryngeal bifurcation of the recurrent laryngeal nerve: similarities and differences between both sides.

Background:Anatomical variations of the recurrent laryngeal nerve (RLN) such as extralaryngeal terminal bifurcation is an important risk for its motor function.Aims:The objective is to study surgical anatomy of bilateral bifurcation of the RLNs in order to decrease risk of vocal cord palsy in patients with bifurcated nerves.Materials and Methods:Surgical anatomy including terminal bifurcation was established in 292 RLNs of 146 patients. We included patients with bilateral bifurcation of RLN in this study. Based on two anatomical landmarks (nerve-artery crossing and laryngeal entry), the cervical course of RLN was classified in four segments: Pre-arterial, arterial, post-arterial and pre-laryngeal. According to these segments, bifurcation point locations along the cervical course of RLNs were compared between both sides in bilateral cases.Results:RLNs were exposed throughout their entire courses. Seventy (48%) patients had bifurcated RLNs. We identified terminal bifurcation in 90 (31%) of 292 RLNs along the cervical course. Bilateral bifurcation was observed in 20 (28.6%) patients with bifurcated RLNs. Bifurcation points were located on arterial and post-arterial segments in 37.5% and 32.5% of cases, respectively. Pre-arterial and pre-laryngeal segments contained bifurcations in 15% of cases. Comparison of both sides indicated that bifurcation points were similar in 5 (25%) and different in 15 (75%) patients with bilateral bifurcation. Permanent nerve injury did not occur in this series.Conclusion:Bilateral bifurcation of both RLNs was observed in approximately 30% of patients with extralaryngeal bifurcation which is a common anatomical variation. Bifurcation occurred in different segments along cervical course of RLN. Bifurcation point locations differed between both sides in the majority of bilateral cases. Increasing surgeons’ awareness of this variation may lead to safely exposing bifurcated nerves and prevent the injury to extralaryngeal terminal branches of RLN.