Vocal Cord Movement Research Articles

Efficacy analysis of ansa cervicalis anterior root-recurrent laryngeal nerve anastomosis in the treatment of unilateral vocal cord paralysis

Objective:Investigates the application and clinical efficacy of ansa cervicalis anterior root-recurrent laryngeal nerve（RLN） anastomosis in the treatment of unilateral vocal fold paralysis（UVFP）. Methods:A prospective study was conducted with 92 UVFP patients admitted to our department from January 2018 to January 2022 who received ansa cervicalis anterior root-RLN anastomosis. The course of nerve injury ranged from 6 to 24 months. Videostroboscopy, voice subjective auditory perceptual assessment（GRBAS）, Voice Handicap Index（VHI-10）, voice objective acoustic analysis and laryngeal electromyography（EMG） were used to evaluate the efficacy of the operation. Results:Videostroboscopy showed that although the movement of vocal cords did not return to normal 12 months after operation, their volume and muscle tension were significantly improved and their positions were adducted to the median or near-median. Also the glottic closure, vocal cord position, vocal cord edge, symmetry and regularity of vocal cord vibration were significantly improved than pre-operation（P<0.01）. The five indexes of GRBAS（Grade, Roughness, Breathiness, Asthenia, Strain） and VHI-10, as well as voice acoustic parameters（Jitter, Shimmer, NHR） post-operation were significantly reduced, while the maximum phonation time（MPT） was significantly longer（P<0.01）. The results of laryngeal EMG indicated that the maximum voluntary motor unit recruitment（VMUR） post-operation was significantly recovered（P<0.01）, which confirmed that the affected laryngeal muscle obtained effective nerve reinnervation. Conclusion:Ansa cervicalis anterior root-RLN anastomosis can effectively improve the voice function of patients which is safe and satisfactory. It is an ideal method for the treatment of unilateral RLN injury.

Factors of postoperative recurrent laryngeal nerve paralysis and recovery of vocal cord movement in thyroid surgery

ObjectivePostoperative recurrent laryngeal nerve paralysis is one of the complications of thyroid surgery, and the prevention and management of paralysis is an important issue for surgeons. In this study, in order to gain further understanding of recurrent laryngeal nerve paralysis after thyroid surgery, we analyzed and examined the usefulness of nerve stimulators for recurrent laryngeal nerve paralysis and the factors that may cause recurrent laryngeal nerve paralysis. Furthermore, in cases where transient recurrent laryngeal nerve paralysis occurred, we analyzed and examined the timing of improvement in vocal cord movement for each intraoperative finding and intraoperative operation that caused the paralysis. MethodsAt the Department of Otorhinolaryngology Head and Neck Surgery, Sapporo Medical University Hospital, between January 2012 and December 2021, the subjects were 543 thyroid surgery cases (692 nerves) without preoperative paralysis or cancer nerve invasion performed. The relationship between postoperative transient and permanent paralysis of the recurrent laryngeal nerve was evaluated using univariate and multivariate analysis. The factors evaluated were gender, age, BMI, total thyroidectomy, benignity, malignancy, Graves’ disease, using IIONM (intermittent intraoperative nerve monitoring), using CIONM (continuous intraoperative nerve monitoring), malignant tumor T3b or higher, with lateral neck dissection, and years of experience of the surgeon. Furthermore, by targeting 87 nerves with transient paralysis, surgical operations were divided into three groups: minor injury, major injury, and adhesion, and their relationship with the timing of postoperative vocal fold movement improvement was evaluated. ResultsPermanent paralysis of the recurrent laryngeal nerve occurred in 12 nerves (1.7 %), and transient paralysis occurred in 100 nerves (14.5 %). Univariate analysis showed no association with each factor, but multivariate analysis showed that transient paralysis was significantly lower in men and in patients using IIONM. The improvement time for vocal cord paralysis was 2.8 months in the minor injury group, 4.5 months in the major injury group, and 3.2 months in the adhesion group, indicating a statistically significant difference between the minor injury group and the major injury group. ConclusionThis study suggests that the use of IIONM and gentle manipulation of women may prevent recurrent laryngeal nerve paralysis during thyroid surgery. In addition, understanding the period of nerve recovery for each operation for postoperative transient recurrent laryngeal nerve paralysis may contribute to patient explanations and determining the timing of therapeutic intervention for speech improvement surgery.

Comparison of propofol versus dexmedetomidine sedation for awake C-MAC® D-Blade video laryngoscopic nasotracheal intubation in patients with difficult airway: A randomised clinical study.

Awake intubation is the preferred method for securing difficult airways. We compared intravenous (IV) propofol and dexmedetomidine for C-MAC® D-blade-guided anticipated difficult nasotracheal intubation under conscious sedation. This randomised study included 60 patients with difficult airway (El-Ganzouri Score 4-9). After adequate airway preparation with IV midazolam 0.03 mg/kg and IV fentanyl 1 µg/kg, in Group P, propofol was infused at 250 µg/kg/min and in Group D, dexmedetomidine was infused at 1 μg/kg over 10 min, then at 0.5 μg/kg/h till a bispectral index (BIS) value 65-70 was achieved. Patients underwent C-MAC® D-blade video laryngoscope-guided nasotracheal intubation. The intubation score was the primary outcome measure. Secondary outcome measures included haemodynamic parameters, intubation time, number of attempts, the incidence of failed awake intubation, glottic view, time to achieve desired BIS, complications, study drug consumption and patient-reported satisfaction with the awake intubation technique. Quantitative variables were compared between groups using unpaired t-test/Welsch test/Mann-Whitney Test. Qualitative variables were correlated using the Chi-square test/Fisher's exact test. A P value of <0.05 was considered statistically significant. The intubation score was significantly higher in Group D versus Group P (P = 0.007). Patient reaction to intubation, haemodynamic parameters and percentage of glottis opening score were more favourable in Group P. Coughing and vocal cord movement were comparable between the groups (P > 0.05). The time to target BIS was four times longer, and the time to intubate was 6 seconds longer in Group D. Successful awake C-MAC® D-blade video laryngoscopic intubation can be performed under dexmedetomidine/propofol conscious sedation, with propofol giving a better intubation score.

Single-Stage Bronchoscopy-Guided Protocol for Tracheostomy Decannulation in Adult Patients

IntroductionTracheostomy decannulation is a routine procedure in airway management. There is no standard decannulation method; however, the two commonly practiced approaches are tracheostomy downsizing and intermittent capping, which are both accompanied by multiple visits to the clinic and increase patient discomfort. Herein, we explore fiberoptic bronchoscopy application in a novel single-stage decannulation protocol. MethodsWe conducted a retrospective study on tracheostomy patients eligible for decannulation. Fiberoptic bronchoscopy was performed on patients with spontaneous ventilation for ≥48 h, age ≥18, hemodynamic stability, normal chest X-ray, adequate swallowing, effective cough, adequate consciousness, patent speaking valve, and absent history of recurrent aspiration. Tracheostomy removal occurred after evaluating the airway and ruling out tracheomalacia, tracheitis with stenosis, obstructive granulation tissue, and moderate-to-severe stenosis. We documented patients' demographic and clinical information, along with details of their post-decannulation course. ResultsOut of 58 patients admitted for tracheostomy removal, we excluded six patients (10.3%) from the study because, despite clinical indications for successful weaning, they exhibited abnormalities that interrupted the decannulation process. Of the remaining 52 patients, 50 (96.1%) were successfully weaned off, while two needed reinsertion during their hospital course. Bronchoscopy findings were unremarkable in 33 (63.5%) patients, and the most frequently observed abnormalities were paucity of vocal cord movement in 5 (9.6%) patients and granulation tissue formation in 5 (9.6%) patients. No further airway management was necessary after discharge. ConclusionsOur study introduces the innovative approach of single-stage bronchoscopic decannulation as a potentially beneficial tool for immediate decannulation. Based on our experience, we achieved a relatively satisfactory outcome following single-stage tracheostomy decannulation with bronchoscopy. The approach shows promise in providing valuable airway insights and predicting possible decannulation failures. Further research is needed to evaluate its impact on stress reduction for patients and surgeons, its superiority compared to traditional techniques, its long-term effects on healthcare, and its potential cost-effectiveness.

Intravenous magnesium sulfate improves orotracheal intubation conditions: A randomized clinical trial

BackgroundMuscle relaxation facilitates orotracheal intubation, but in some situations, neuromuscular blocking agents may be contraindicated. AimTo study the effect of intravenous magnesium sulfate perfusion before induction on orotracheal intubation conditions and the pressor response upon intubation. MethodsThis prospective, randomized, double-blind trial compared magnesium sulfate with saline solution as a placebo. The patients were randomized into two groups: the magnesium group (Group Mg+), which received 50 mg/kg of magnesium sulfate in 100 ml of saline 15 min before induction of anesthesia, and the saline group (Group Mg-), which received only 100 ml of saline 15 min before induction of anesthesia without magnesium sulfate. The induction in both groups was performed without neuromuscular blocking agents.Intubation conditions in both groups were compared using the Copenhagen consensus conference: ease of laryngoscopy, vocal cord position and/or movement, and response to intubation or cuff (cough or diaphragmatic movement). Intubation conditions were considered acceptable (excellent or good) or unacceptable (poor). Systolic, diastolic arterial pressures and heart rate were also recorded during the study. ResultsIn total, 76 patients (38 in each group) were included in this study. Clinically acceptable intubation conditions were significantly more observed in the magnesium group Mg + compared to the saline group Mg-: 36 patients (95 %) vs. 15 patients (39 %) (P < 0.001).Hemodynamic stability was more observed in the magnesium group, with a statistically significant lower heart rate throughout Mg + compared to the saline group. ConclusionAdministration of magnesium sulfate before induction of anesthesia significantly improved intubation conditions without the need for neuromuscular blocking agents.

Comparison of the diagnostic and prognostic abilities of flexible laryngoscopy and dynamic digital radiography for vocal cord paralysis: A prospective observational study.

Although flexible laryngoscopy (FL) is the reference modality for diagnosing vocal cord paralysis (VCP), FL involves patient discomfort and insertion intolerance. Dynamic digital radiography (DDR) with high spatial and temporal resolution is easier to use and less invasive when evaluating VCP. Seventy-eight patients underwent FL and DDR before and after neck surgery. Qualitative and quantitative vocal cord movement (VCM) evaluations were conducted. Patients with postoperative VCP were followed-up regularly. DDR exhibited diagnostic performance with 67% sensitivity and 100% specificity. The cutoff for VCM was 2.4 mm, with DDR exhibiting 100% sensitivity and 78% specificity. All cords with transient VCP had positive VCM at both 3 weeks and 2 months. Additionally, 50% and 75% of cords with permanent VCP had negative VCM at 3 weeks and 2 months, respectively. DDR is promising for the diagnosis of postoperative VCP and early prediction of permanent postoperative VCP.

Assessment of pre-extubating recurrent laryngeal nerve palsy using ultrasound in postoperative patients with esophageal cancer: a prospective observational study.

Ultrasound performed after extubation has been suggested to be useful for the diagnosis of recurrent laryngeal nerve (RLN) paralysis. However, the use of ultrasound for this purpose before extubation has not been examined. The aim of this study was to examine the versatility (interrater reliability) and usefulness of ultrasound for evaluating the movement of vocal cords before extubation. The subjects were 30 patients who underwent radical surgery for esophageal cancer from August 2020 to December 2021. An experienced examiner performed an ultrasound examination before and after elective extubation on the day after surgery to evaluate RLN paralysis and record videos. Bronchoscopy was then performed to make a definite diagnosis. Three anesthetists blinded to the diagnosis also evaluated the cases using the videos, and the versatility of the examination was determined using a kappa test. The diagnostic accuracies of the examiner and three anesthetists were 76.7%, 50.0%, 53.3%, and 46.7%, respectively, and the kappa coefficients for the examiner with the anesthetists were 0.310, 0.502, and 0.169, respectively. The sensitivity, specificity, positive predictive value and negative predictive value for diagnosis of RLN paralysis by the examiner using ultrasound before extubation were 0.57, 0.95, 0.80, and 0.87, respectively. These results indicate a lack of versatility of the ultrasound examination based on the low kappa coefficients. However, with an experienced examiner, ultrasound can serve as a non-invasive examination that can be performed before extubation with high accuracy and specificity for diagnosis of postoperative RLN paralysis.

Atracurium for Rapid Sequence Induction; A dose determining Randomized Control Trial at a Tertiary Care Hospital.

Introduction: Expert airway management is one of the essential anesthetic skills. Rapid Sequence induction is a technique of providing rapid securement of airway with endotracheal tube in patients who are at risk of aspiration. Objective: To find out the efficacy of 3-4 ED95 dose of Atracurium in providing optimal intubating conditions for Rapid Sequence Induction. Methodology: Single-blind randomized control trial was carried out Department of Anesthesia and Critical Care Medicine, Pakistan Institute of Medical Sciences (PIMS), Islamabad. 118 patients were included and divided into two groups by help of computer-generated random numbers. All the patients were pre-medicated with 8 mg of IV Dexamethasone. Group A patients received 1 mg/kg while group B patients received 0.75 mg/kg of Atracurium. Intubating conditions were assessed on the basis of number of coughing episodes along with degree of vocal cord movement or paralysis. Results: Patients who received 0.75 mg/kg of Atracurium had statistically significant better intubating conditions as compared to those receiving 1 mg/kg of Atracurium (p value &lt; 0.05). Coughing episodes were more common among patients receiving higher dose of Atracurium while degree of vocal cord paralysis was similar in both groups. Furthermore 75% of histamine related adverse effects such as erythema and bronchospasm were observed in higher dose group. The difference was statistically significant with a p value of &lt;0.05. Conclusion: Atracurium at a dose of 0.75 mg/kg along with pre-medication with 8 mg of IV Dexamethasone provided better and safer intubating conditions for rapid sequence induction.

Three Episodes of Postanesthesia Paradoxical Vocal Cord Motion Disorder in the Same Patient: A Case Report.

Postanesthesia paradoxical vocal cord motion disorder (PVCMD) is often benign. However, if not recognized, PVCMD can lead to unnecessary treatments. Our patient had 3 different surgeries over a period of 20 months. The first episode of PVCMD occurred after a shoulder surgery, and the patient was reintubated. PVCMD was correctly diagnosed and treated successfully with reassurance after an ulnar nerve decompression. The third episode of PVCMD occurred after a cervical fusion surgery. Prevertebral edema from surgery further compromised the airways. Our case demonstrates the challenges of identifying and managing perioperative PVCMD, especially when surgical complications confound the airway management.

Effect of Melatonin Administration on Nerve Regeneration after Recurrent Laryngeal Nerve Injury.

Recurrent Laryngeal Nerve (RLN) injury is a complication in neck surgery. The aim of this study is to evaluate the effect of primary suture repair with melatonin treatment on nerve regeneration after RLN damage. After the RLN damage, nerve repair was performed in the first and fourth groups. The third and fourth groups were given intraperitoneal melatonin therapy daily for six weeks. EMG was applied to all subjects and vocal cord movements were evaluated endoscopically. At the end of the sixth week, all subjects were sacrificed, and their larynx were examinedhistologically. Vocal cord paralysis (VCP) was observed in all subjects after RLN damage. In the sixth week, improvement was observed in the first and fourth group who underwent nerve repair, whereas none in the second and third group, who did not undergo nerve repair, improved. With EMG, the highest MUP was in the fourth group. Histologically, an increase in Schwann cells, a decrease in axon damage, and cytoplasmic vacuolization were in the fourth group. Myelin protein zero and Ki-67 staining were the most in the fourth group. In our study, laryngoscopic, electrophysiological and histopathological findings show that melatonin contributes to nerve healing but this could not translate into functional recovery.

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

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. This retrospective study examined 96 patients with esophageal cancer who underwent MIE between January 2021 and December 2022, using both TLUSG and endoscopy. 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). 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.

Efficiency of face mask ventilation before and after neuromuscular blockade: A randomised, double-blind controlled study.

The traditional practice of administrating neuromuscular blocking drugs (NMBDs) after checking face mask ventilation is challenged repeatedly. This study compared the efficiency of face mask ventilation before and after administrating an NMBD in a patient with a normal airway. The secondary outcome measured was the grade of mask ventilation and tracheal intubating conditions. After ethical approval, patients (n = 120) in the age group of 18-65 years scheduled for elective surgery under general anaesthesia were randomly assigned into two groups. Group 1 received an NMBD before checking face mask ventilation. Group 2 received an NMBD after checking face mask ventilation. Lungs were ventilated for 180 s, during which expiratory tidal volume (Vte) was recorded as the primary outcome. Hans's grading for face mask ventilation was used to grade mask ventilation. The ease of intubation was assessed based on intubating conditions (ease of laryngoscopy, vocal cord movement, and limb movement). SPSS 20.0 software was used for statistical analysis. For a total of 180 seconds of mask ventilation, the mean (standard deviation) Vte measured after apnoea was significantly higher in Group 1 versus Group 2 [471.9 (63.3) vs 434.8 (77.0) mL/breath, P = 0.004]. The intubating condition was either excellent or good in all patients. The administration of NMBDs resulted in a larger mask Vte and shorter intubation time.

Risk of dysphagia in a population of infants born pre-term: characteristic risk factors in a tertiary NICU

ObjectiveTo examine the prevalence and characteristics of dysphagia and suck-swallow-breath incoordination as phenotypes of oral feeding difficulties. MethodA cross-sectional study with secondary data collected consecutively over 2 years from October 2020 to October 2022 to measure the prevalence of swallowing and oral feeding difficulty in preterm infants using Flexible endoscopic evaluation of swallowing examination at the tertiary Integrated Dysphagia Clinic. ResultsThe prevalence of swallowing disorders was 25 % and the prevalence of suck-swallow-breath incoordination was 62.5 %. The significant risk factor that may show a possible correlation with oral feeding difficulty was mature post-menstrual age (p = 0.006) and longer length of stay (p = 0.004). The dominant percentage of upper airway abnormality and disorder were retropalatal collapse (40 %), laryngomalacia (42.5 %), paradoxical vocal cord movement (12.5 %), and gastroesophageal reflux disease (60 %). The dominant characteristic of oral motor examination and flexible endoscopic evaluation of swallowing examination was inadequate non-nutritive sucking (45 %), inadequate postural tone (35 %), and inadequate nutritive sucking (65 %). ConclusionDysphagia in preterm infants is mostly observed in those with mature post-menstrual age, longer length of stay, and the presence of gastroesophageal reflux disease with inadequate non-nutritive sucking and nutritive sucking abilities. Suck-swallow-breath incoordination is primarily observed in those with immature post-menstrual age, a higher prevalence of cardiopulmonary comorbidity, and a higher prevalence of upper airway pathologies (laryngomalacia, paradoxical vocal cord movement) with inadequate nutritive sucking ability.

The consensus among experts on the diagnosis and treatment of pediatric vocal cord paralysis

Pediatric vocal ford paralysis is a vocal cord movement disorder caused by damage to the pediatric laryngeal motor nerves.It is mainly characterized by voice, breathing,and swallowing difficulties,and in severe cases,it can lead to choking in affected children. Currently, the diagnosis and treatment of this condition pose a significant challenge for pediatric otolaryngologists, as the goal is to minimize damage to the vocal folds and laryngeal framework.In order to standardize the diagnosis and treatment of pediatric vocal cord paralysis, the Pediatric Otolaryngology Committee of the Chinese Medical Association,in collaboration with multiple children's medical centers nationwide, have formulated this consensus document.

The Effects of Magnesium Sulphate on Integrated Pulmonary Index Scores and Propofol Consumption During Endobronchial Ultrasonography: A Retrospective Study.

Aim Our aim in this studywas to investigate the effect of inhaled and intravenous (iv) magnesium (Mg) use on Integrated Pulmonary Index (IPI) score and propofol consumption in patients undergoing endobronchial ultrasonography (EBUS) procedure under sedoanalgesia. Materials and methods After obtaining the approval of the local ethics committee, the files of 96 patients aged 18-75 who underwent EBUS were reviewed retrospectively. Patients using Mg were classified as the M group, and patients not using Mg were classified as the control (C) group. IPI values, amount of propofol consumed, and intubation scores of group M and group C were evaluated. Results When the intubation score values ​​at the time of the bronchoscope passing through the vocal cords (assessment of vocal cord movement, cough reflex, and leg movement) during the EBUS procedure were compared, the intubation conditions were found to be significantly better in the M group than in the C group (p<0.05). Group M had less cough reflex than group C (p<0.05). IPI scores were significantly higher in the M group than in the C group at the 10th and 15th minutes (p<0.05). Total propofol consumption was found to be significantly lower in the M group(254.61±82.80 mg)than in the C group (321.25±90.04 mg) (p<0.05). Conclusion According to our results, the use of intravenous and inhaler Mg in addition to propofol sedation during the EBUS procedure may improve the respiratory parameters and can also significantly reduce the propofol dose.

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

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

Vocal Cord Monitoring by Flexible Fiberoptic Laryngoscopy During Thyroid Radiofrequency Ablation.

Introduction: Thermal injury to recurrent laryngeal nerve (RLN) during radiofrequency ablation (RFA) can produce temporary or permanent vocal cord paralysis.1 Hydrodissection with cold 5% glucose of "danger triangle" protects RLN during RFA.2 When RFA is performed under local anesthesia, RLN function is monitored by patients producing vocal sounds.3 Large lesions requiring longer RFAs warrant general sedation where voice cannot be assessed, therefore, an additional technique for RLN protection is advisable. Observation of passive symmetrical vocal cord movements during breathing by laryngeal ultrasonography is useful in assessing vocal cord function4; however, flexible-fiberoptic fibrolaringoscopy (FFL) is gold standard for assessing vocal cord movements,5 anticipating potential RLN damage. We report FFL monitoring during RFA under general sedation on a large thyroid nodule. FFL during RFA may detect RLN irritation and dysfunction if asymmetry in passive vocal cord movements is noted. Should asymmetry appear, RFA operator stops delivering energy and repositions electrode needle. Materials and Methods: Thyroid function tests, blood glucose, creatinine, transaminase, International-Normalized-Ratio, and electrocardiogram were performed. Operating room (OR) layout created sufficient space for ear-nose-throat (ENT) and RFA operators. An examination with a fiberscope camera demonstrated normal vocal cord adduction during phonation and abduction during breathing. The procedure was assisted by an anesthetist administering fentanyl 50 mcg, midazolam 1.5 to 5.0 mg, and propofol infusion 2 mg/(kg·h). General sedation was conducted so that reflexes were attenuated but still observable. Incorporating in OR by an anesthetist who performs general sedation reduces side effects and complications.6 Ultrasonography showed a 34-mL right lobe nodule abutting on the RLN area. After sedation with propofol, the ENT specialist inserted an endoscope until the glottic plane. During calm breathing, vocal cords moved symmetrically. After obtaining anterior nodule hydrodissection from strap and sternocleidomastoid muscles with 10 mL of 2% lidocaine, posterior hydrodissection was achieved by ultrasound-guided administration of 30 mL of 5% cold glucose. Anterior and posterior hydrodissections merged, separating nodule from neck structures. The radiofrequency electrode needle was then inserted into the nodule, initially positioned in inferior nodule portion adjacent to danger triangle previously isolated by hydrodissection. Initial power was 30 watts. Moving-shot technique was used. Results: FFL was performed throughout thyroid RFA. Symmetric vocal cord movements during breathing demonstrated no RLN irritation. FFL monitoring allowed observation of natural reflexive phenomena, including swallowing. Complete nodule ablation was achieved. FFL performed post-RFA confirmed normal vocal cord motility. Conclusions: We report the first-time use of FFL for vocal cord monitoring during RFA. FFL was easily performed by the ENT specialist and well tolerated by the patient. Avoiding danger triangle and precise RFA needle positioning is key in preventing RLN injury. Benign nodules regrow if total ablation is not achieved7 and some authors propose additional procedures to complete ablation8 that obviously incurs costs. Total RFA nodule ablation-assisted FFL monitoring eliminates the need for repetitive RFAs, thus reducing overall treatment costs. Finally, FFL monitoring does not prolong procedure, as it is performed simultaneously with RFA. FFL is a valid technique when used in conjunction with hydrodissection to further prevent RLN thermal injury during RFA, especially indicated for large thyroid nodule ablation and professional voice users. Patient Consent and Permission: The patient provided written consent for FFL monitoring and permission to use his portrayals and ultrasonographic images during RFA. The study was completed in accordance with the Declaration of Helsinki as revised in 2013. Adherence to institutional review board protocols was granted. Disclaimer: Representation of any instrumentation within the video does not indicate any endorsement of the product and/or company by the publisher, the American Thyroid Association, or the authors. No competing financial interests exist. Runtime of video: 9 mins 39 secs.

Lymphoma recurrence presenting as vocal cord fixation.

Lymphomas of the larynx are a rare finding. Those with lymphoma of the larynx often present with symptoms such as vocal hoarseness, throat pain, dysphagia, and weight loss. This is a case of a 74-year-old man who presents with new onset of hoarseness and dysphagia. He has a previous history of diffuse large B-cell lymphoma (DLBCL) but was thought to be in remission at the time of presentation. On nasolaryngoscopy, there was a large, right sided, sub-mucosal mass with right vocal cord fixation. Physical exam and computed topography of the neck did not identify any adenopathy. Biopsy confirmed the recurrence of DLBCL isolated to the larynx at the time of diagnosis. The patient was treated with chemotherapy and fully recovered his vocal cord motion with resolution of his hoarseness and dysphagia. Physicians should consider lymphoma in patients presenting with laryngeal complaints especially in patients with a history of lymphoma.

갑상선 수술 중 신경 손상에 대한 예방과 치료

Since most thyroid cancers are slowly growing and are not fatal, prevention of surgical complications is as important as removing the lesion. Although permanent vocal cord paralysis, a significant complication of thyroid surgery, is reported to occur in about 1-2% of cases, the actual incidence is expected to be higher for various reasons. When nerve damage occurs despite the surgeon's utmost care, appropriate measures should be taken immediately. However, even with the most aggressive approach, nerve repair (neurorraphy) rarely restores normal vocal cord movement; it is known only to maintain tension in the vocal cords to prevent atrophy. Therefore, preventing nerve damage is considered much more important. To achieve this goal, a thorough preoperative examination and understanding of the anatomical variations of the nerves around the thyroid, as well as precise and careful capsular dissection, are necessary. In this paper, the authors discuss methods for preventing and treating nerve damage during thyroid surgery.

3D VOSNet: Segmentation of endoscopic images of the larynx with subsequent generation of indicators

Video laryngoscope is available for visualizing the motion of vocal cords and aid in the assessment of analyzing the larynx-related lesion preliminarily. Laryngeal Electromyography (EMG) needs to be performed to diagnose the factors of vocal cord paralysis, which may cause patient feeling unwell. Thus, the problem is the lack of credible larynx indicators to evaluate larynx-related diseases in the department of otolaryngology. Therefore, this paper aims to propose a 3D VOSNet model, which has the characteristics of sequence segmentation to extract the time-series features in the video laryngoscope. The 3D VOSNet model can keep the time-series features of three images before and after of the specific image to achieve translation and occlusion invariance, which explicitly signifies that our model can segment and classify each item in the video of laryngoscopy not affected by extrinsic causes such as shaking or occlusion during laryngoscope. Numerical results revealed that the testing accuracy rates of the glottal, right vocal cord, and the left vocal cord are 89.91%, 94.63%, and 93.48%, respectively. Our proposed model can segment glottal and vocal cords from the sequence of laryngoscopy. Finally, using the proposed algorithm computes six larynx indicators, which are the area of the glottal, area of vocal cords, length of vocal cords, deviation of length of vocal cords, and symmetry of the vocal cords. In order to assist otolaryngologists in staying credible and objective when making decisions without any doubt during diagnosis and also explaining the clinical symptoms of the larynx such as vocal cord paralysis to patients after diagnosis, our proposed algorithm provides otolaryngologists with explainable indicators (X-indicators).