A Novel Lateral Approach to the Assessment of Vocal Cord Movement by Ultrasonography

2024 International Expert Consensus on US-guided Thermal Ablation for T1N0M0 Papillary Thyroid Cancer

Thermal ablation has started to gain acceptance as a therapeutic approach for the management of papillary thyroid cancer (PTC), mainly in the T1 stage (tumor size ≤ 2 cm in greatest dimension and limited to the thyroid). Despite its increasing popularity, a lack of uniformity in the technical details persists, and existing guidelines do not fully align with recent research advancements. To standardize the use of US-guided thermal ablation for T1N0M0 PTC, a panel of experts jointly issued this expert consensus on thermal ablation for PTC. This consensus was developed by experts with specific competence and expertise in this field through rounds of the modified Delphi method. An evidence-based approach incorporating the practical experience of the panelists was adopted. The consensus was developed through extensive discussions, systematic literature review with meta-analysis, and expert evaluations. In this consensus, a total of 27 recommendations are made, addressing the indications and contraindications for thermal ablation for PTC, physician training, preoperative preparation, technical procedures, complications, efficacy assessment, and follow-up strategies. This expert consensus provides up-to-date, high-quality, standardized guidance to harmonize treatment practices, enhance patient outcomes, and potentially shape future research and policy developments in the management of T1N0M0 PTC using US-guided thermal ablation.

Use of Laryngeal Ultrasound to Observe Laryngeal Movements During Noninvasive Ventilation in Healthy Volunteers

Background: Transnasal fiberoptic laryngoscopy (TFL) has revealed that laryngeal obstruction can hamper assisted ventilation. TFL may be considered invasive, and laryngeal ultrasound (US) could be a noninvasive alternative. The objective of this study was to investigate the feasibility of using laryngeal US to study laryngeal movements in healthy adult volunteers undergoing noninvasive ventilation (NIV) and to compare the observations with those of simultaneous TFL. Methods: In this cross-sectional study, 30 participants (19 females, age 22-65 y) underwent simultaneous video-recorded TFL and laryngeal US, breathing with and without NIV. Laryngeal US was repeated for anterior and both lateral approaches; the last 5 breaths from each assessment were analyzed. The participants rated discomfort using a numeric rating scale (NRS) from 0 (no discomfort)-10 (worst). Two blinded raters separately described and scored the TFL and laryngeal US recordings, and the findings were subsequently compared. The last 10 laryngeal US recordings were tested for interrater reliability. Results: All participants were successfully assessed using the anterior and both lateral laryngeal US approaches during NIV. Both techniques were well tolerated; 5/30 scored 0 on NRS for TFL and 22/30 for laryngeal US. The visualization rate for all recorded breaths was 99.1% for TFL compared to 81.7% for laryngeal US; overall concordance rate was 84.6%. The discordance rate for the TFL versus laryngeal US observations was 11.1% for vocal fold movements and 11.7% for aryepiglottic fold movements. Interrater reliability showed substantial agreement (0.71). Conclusions: Laryngeal US emerged as a feasible method to describe laryngeal movements during NIV, providing high-quality observations and high concordance with TFL.

Ultrasonography of the cricoarytenoid joint and its movements

OBJECTIVE

Ultrasound provides real-time anatomical information and motion. We used ultrasound to image the cricoarytenoid joint and its rotating, rocking, and gliding movements.

METHODS

Between March and October 2023, 20 patients (10 males and 10 females) who visited our hospital underwent laryngeal ultrasonography. The joint cavity was delineated in four patients (20 %, two males and two females). Conversely, the other patients did not detect it because of acoustic shadows on ultrasonography. We also performed ultrasonography on five volunteers (three males and two females), but only two of them (two females) showed imaging of the joint cavity. Herein, we report the case of a female volunteer in her 30 s who had the best delineation of joint movements.

RESULTS

Joint movements were three-dimensional, whereas ultrasound images were two-dimensional. However, combined with scanning techniques, characteristic joint movements were successfully imaged using ultrasound. Initially, we performed a trans-thyroid cartilage transversal procedure to visualize the muscular process of the arytenoid cartilage and rotational movement. Subsequently, the probe was rotated to an oblique position, and the articular cavity of the cricoarytenoid joint was visualized. We then observed the rocking and gliding movements. In Addition, we demonstrated a seamless transition from gliding to rocking. Finally, we observed that the arytenoid cartilage was pulled toward the posterior cricoarytenoid muscle (PCA) during sniffing. The PCA is the only muscle opening the vocal cords, so the arytenoid cartilage shifts toward the PCA and tilts outward from the larynx.

CONCLUSION

The presented probe scanning techniques and specific joint movements may help identify notable conditions such as arthritis or joint dislocation.

Transcutaneous Laryngeal Ultrasound for Assessing Hyaluronic Acid Status in Patients Undergoing Injection Laryngoplasty

OBJECTIVE

Injection laryngoplasty (IL) with hyaluronic acid (HA) is an effective treatment for patients with glottic insufficiency. The duration of HA maintenance in the vocal fold remains unknown. In this study, transcutaneous laryngeal ultrasound (TLUS) was used to evaluate the absorption and migration of HA after IL. Subsequent management might be provided based on the TLUS finding.

METHODS

Patients diagnosed with unilateral vocal fold paralysis (UVFP) or vocal fold atrophy were recruited. All patients underwent IL with HA in an office-based setting along with TLUS to monitor the status of HA. The schedule of TLUS included assessments before and after IL until non-visualization.

RESULTS

The study population comprised 38 women and 17 men. Of the patients, 54.1% underwent IL for UVFP, whereas 45.9% underwent IL for vocal fold atrophy. Multivariate Cox regression analysis for factors affecting HA absorption revealed that the cause of injection was the most important independent predictor (hazard ratio [HR], 2.15; 95% confidence interval [CI], 1.03-4.46; p = 0.040). The duration of HA maintenance was significantly longer in patients with UVFP than in those with vocal fold atrophy (8.77 vs. 4.70 months, HR, 2.33; 95% CI, 5.47-8.18; p = 0.002).

CONCLUSION

TLUS is an objective assessment method for patients undergoing IL with HA. Subsequent tailor-made management could be offered based on the TLUS findings during follow-up. For patients at high risk of upper respiratory tract infection or who are intolerant to flexible nasopharyngoscopy, TLUS can be used as an alternative tool to evaluate the condition of the glottis after IL with HA.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:4682-4687, 2024.

Quantitative Assessment of True Vocal Fold Movement by the Lateral-Approach Laryngeal Ultrasonography: A Pilot Study

BACKGROUND/OBJECTIVES

Ultrasonography is a new method for subjective and qualitative assessment of true vocal fold movement, and true vocal fold visualization with the lateral approach could be better than that with the anterior approach. Our aim was to explore the feasibility of lateral-approach ultrasonography in objective and quantitative assessment of true vocal fold movement.

METHODS

The lateral-approach laryngeal ultrasonography was performed during calm breathing and breath-holding on young healthy adult volunteers in Shanghai, China. The morphology and anatomical position of false vocal fold, true vocal fold, and arytenoid cartilage were observed and measured through the ultrasonic self-contained measurement function. All parameters, including the distance from false vocal fold to thyroid cartilage lamina, true vocal fold length, and the distance from true vocal fold to thyroid cartilage lamina, were obtained at the end of the calm inspiratory and breath-holding phases. Data were analyzed using a t test (P < 0.05).

RESULTS

Forty healthy adult volunteers (age 20 to 34 years, body mass index 19.5 to 23.8 kg/m2, 20 males and 20 females) with satisfactory ultrasonic images were included in the study. There were no significant differences in all laryngeal parameters between the left and right sides in either phase (P > 0.05). From the end of the calm inspiratory phase to the breath-holding phase, changes in all laryngeal parameters were significantly different (P < 0.05), regardless of gender.

CONCLUSIONS

This study demonstrated that the lateral-approach laryngeal ultrasonography seemed feasible to quantify and objectively assess true vocal fold movement, utilizing differences between laryngeal parameters before and after true vocal fold movement.

Utilizing Surgeon-Performed Intraoperative Translaryngeal Ultrasound for Verifying Vocal Fold Function: A Troubleshooting Approach for Intraoperative Neuromonitoring in Neck Surgery

INTRODUCTION

We investigated transcutaneous laryngeal ultrasonography (TLUS) for assessing vocal fold (VF) mobility during thyroid and parathyroid surgeries, emphasizing its precision and utility in signal loss scenarios.

METHODS

Between October 2020 and January 2023, we performed TLUS, Doppler sonography, laryngeal twitch response (LTR) palpation, and electromyography (EMG) to monitor recurrent laryngeal nerve function during neck surgeries. Postoperatively, the VF activity was verified using fiberoptic video laryngoscopy (FL). Concordance with FL was categorized based on VF activity.

RESULTS

Of the 443 VF evaluations, no instances of permanent bilateral paralysis were noted. Temporary unilateral palsy was found in 3.38% and permanent in 0.45%. TLUS displayed 97.8% agreement with EMG and was diagnostically superior (99.7% vs 98.2%) and more affordable ($68 vs $300) compared to analogous operative durations.

CONCLUSION

TLUS rivals EMG in terms of intraoperative neuromonitoring accuracy and outperforms LTR. Being cost-effective, TLUS can effectively address signal loss situations, thereby averting additional surgeries.

Can Transcutaneous Laryngeal Ultrasonography Systematically Quantify Vocal Fold Movement?-A Feasibility Study

OBJECTIVES

Several studies have assessed adult vocal fold movement using transcutaneous laryngeal ultrasonography (TLUSG) during the perioperative period of thyroidectomy. However, the movement was not objectively quantified. This study aimed to provide a feasible and objective method for assessing vocal fold movement using TLUSG.

STUDY DESIGN

Feasibility study.

METHODS

TLUSG was performed during calm breathing and breath-holding in healthy adult volunteers. The morphology and anatomy of the larynx were observed and measured using an ultrasonic self-contained measurement function. At the end of the calm inspiratory and breath-holding phases, vocal fold angle, vocal fold length, distance from vocal process to the midline, distance from anterior vocal commissure to arytenoid cartilage, distance from false vocal fold to the midline, and distance from the anterior horn of thyroid cartilage to false vocal fold were measured. Data were analyzed using a t test (significance <0.05).

RESULTS

The ultrasonic images were satisfactory in all 40 healthy adult volunteers (age 19-35 years; body mass index 18.55-23.93 kg/m2; 20 men and 20 women). There were no significant differences in all laryngeal parameters between the left and right sides in both phases (P > 0.05). Moreover, all differences in laryngeal parameters between the end of the calm inspiratory phase and the breath-holding phase were statistically significant (P < 0.05), regardless of sex.

CONCLUSION

The relevant positional parameters of the vocal fold, arytenoid cartilage, and false vocal fold and their differences before and after vocal fold movement in healthy adult volunteers can be obtained objectively using TLUSG.

A single-arm, prospective study comparing translaryngeal ultrasonography with direct visualisation by flexible laryngoscopy for vocal cord assessment in patients undergoing oesophagectomy or mediastinoscopy

Background and Aims

Translaryngeal ultrasonography (TLUSG) for diagnosis of vocal cord palsy, a relatively new, safe and noninvasive bedside technique with minimal risk of respiratory infection transmission, has been effective in patients with thyroid disease. We studied its use as an alternative method to visual inspection by flexible laryngoscopy (FL) for vocal cord assessment in patients undergoing thoracic surgeries.

Methods

After Institutional Ethics Committee approval and trial registration, in this single-arm, prospective study, the vocal cord function of 110 patients who underwent either total oesophagectomy or mediastinoscopy was assessed immediately after extubation by both FL and TLUSG. A follow-up assessment was done by laryngoscopy using Hopkin's endoscope (HL) and a repeat TLUSG. The primary outcome was the concordance between direct visualisation (FL or HL) and TLUSG.

Results

Vocal cords were successfully visualised by TLUSG in 90% of male and all female patients. Findings of FL and TLUSG done at the first assessment matched in 89 (86.4%) out of 103 patients, and the degree of concordance was 0.69 (95% confidence interval [CI] =0.52-0.83). At the second assessment, HL and TLUSG findings matched in 83 (94.3%) out of 88 patients, and the degree of concordance was 0.89 (95% CI = 0.77-0.98).

Conclusion

TLUSG is an effective noninvasive alternative to direct visualisation for vocal cord assessment in both male and female patients undergoing thoracic surgery.

Ultrasonography for Eating and Swallowing Assessment: A Narrative Review of Integrated Insights for Noninvasive Clinical Practice

Dysphagia is a syndrome of abnormal eating function resulting from a variety of causative diseases, and is associated with malnutrition. To date, the swallowing function has been difficult to examine without the use of invasive and expensive methods, such as the videofluorographic swallowing study or fiberoptic endoscopic evaluation of swallowing. In recent years, progress has been made in the clinical application of ultrasound equipment for the evaluation of body compositions near the body surface, including the assessment of nutritional status. Ultrasound examination is a noninvasive procedure and relatively inexpensive, and the equipment required is highly portable thanks to innovations such as wireless probes and tablet monitoring devices. The process of using ultrasound to visualize the geniohyoid muscle, digastric muscle, mylohyoid muscle, hyoid bone, tongue, masseter muscle, genioglossus muscle, orbicularis oris muscle, temporalis muscle, pharynx, esophagus, and larynx, and the methods used for evaluating these structures, are provided in this study in detail. This study also aims to propose a protocol for the assessment of swallowing-related muscles that can be applied in real-world clinical practice for the diagnosis of sarcopenic dysphagia, which can occur in elderly patients with sarcopenia, and has received much attention in recent years.

[Polypositional transcutaneous ultrasound assessment of vocal folds mobility. Ultrasonographic sign of laryngeal dysfunction]

Fiberoptic laryngoscopy is a standard procedure for evaluation of vocal folds immobility. However, this method is invasive, requires special qualifications and technical equipment, which limits its routine use. Therefore, in daily practice, the vast majority of laryngoscopy are performed by an indirect way, the accuracy of which depends on the specialist experience and the patient compliance. On the other hand, a large number of patients require for a convenient, non-invasive and inexpensive approach to assess the vocal folds mobility. The transcutaneous laryngeal ultrasonography can be such a method. However, the disadvantage of this technique is low informative value.

OBJECTIVE

To increase the effectiveness of the diagnosis of laryngeal dysfunction using transcutaneous laryngeal ultrasonography.

MATERIAL AND METHODS

Patients underwent laryngeal ultrasonography and videolaryngoscopy before and after thyroid or parathyroid surgery. Ultrasound was performed polypositionally in the transverse and oblique planes. Functional tests with breathing and breath holding were used. Qualitative (the smile or flying bird signs, the vertical closing line of the vocal folds, synchronicity and symmetry movement of the arytenoid cartilages) and quantitative (the length contraction of the vocal cord, the rotation angle of the arytenoid cartilage) ultrasonic parameters determin the normal vocal folds mobility.

RESULTS

996 patients were included in the study. Vocal folds paresis was detected in 106 (10.6%) patients. In 72 (7.2%) cases partial impaired mobility of the vocal folds (laryngeal dyskinesia) were detected. The echographic patterns of these patients were analyzed. Qualitative ultrasound signs of laryngeal dysfunction were identified: a crooked smile or falling bird signs, a closing line deformation of the vocal folds, an arytenoid immobility. Quantitative ultrasound signs included: a decrease in the length contraction of the vocal cord and a reduction of rotation angle of the arytenoid cartilage. Unilateral laryngeal paresis was diagnosed in 101 (10.1%) patients. In unilateral disorders the rotation angle of the arytenoid on the affected side was 0-14° and the length contraction of the vocal cord was 0-1.8 mm. A crooked smile or falling bird signs, a closing line deformation of the vocal folds and immobility of the arytenoid cartilages were also determined. In 5 (0.5%) cases bilateral laryngeal paresis was revealed, in which on both sides the rotation angles of the arytenoid were 0-14°, and the length contraction of the vocal cords was 0-1.8 mm. At the same time there was no a smile or flying bird signs and a closing line of the vocal folds. Laryngeal dyskinesia was characterized by a crooked smile or falling bird signs and a closing line deformation of the vocal folds. At the same time, partial mobility of the arytenoid cartilage was noted in comparison with the contralateral side (there was a difference in the rotation angle of the arytenoid between the right and left sides of 15 ° or more degrees).

CONCLUSION

The sensitivity and specificity polypositional ultrasound of the vocal folds in women were 100% and 99.8%, in men - 85.7% and 99.2%, respectively.

Vocal cord dysfunction/inducible laryngeal obstruction: novel diagnostics and therapeutics

INTRODUCTION

Vocal cord dysfunction/inducible laryngeal obstruction (VCD/ILO) is an important medical condition but understanding of the condition is imperfect. It occurs in healthy people but often co-exists with asthma. Models of VCD/ILO pathophysiology highlight predisposing factors rather than specific mechanisms and disease expression varies between people, which is seldom appreciated. Diagnosis is often delayed, and the treatment is not evidence based.

AREAS COVERED

A unified pathophysiological model and disease phenotypes have been proposed. Diagnosis is conventionally made by laryngoscopy during inspiration with vocal cord narrowing >50% Recently, dynamic CT larynx was shown to have high specificity (>80%) with potential as a noninvasive, swift, and quantifiable diagnostic modality. Treatment entails laryngeal retraining with speech pathology intervention and experimental therapies such as botulinum toxin injection. Multidisciplinary team (MDT) clinics are a novel innovation with demonstrated benefits including accurate diagnosis, selection of appropriate treatment, and reductions in oral corticosteroid exposure.

EXPERT OPINION

Delayed diagnosis of VCD/ILO is pervasive, often leading to detrimental treatments. Phenotypes require validation and CT larynx can reduce the necessity for laryngoscopy, thereby fast-tracking diagnosis. MDT clinics can optimize management. Randomized controlled trials are essential to validate speech pathology intervention and other treatment modalities and to establish international standards of care.

Laryngeal Ultrasound Detects Vocal Fold Immobility in Adults: A Systematic Review

Laryngeal ultrasound (US) is becoming widely accepted for assessing true vocal fold immobility (TVFI), a potential complication of laryngeal and thyroid surgery. The objective of this project is to perform a systematic review and meta-analysis of pooled evidence surrounding laryngeal US as a modality for diagnosing TVFI in adults at risk for the condition in comparison to laryngoscopy as a gold standard. Medical subject heading terms were used to search MEDLINE, Embase, Google Scholar, Web of Science, and the Cochrane Library for relevant citations from January 1, 2000, to June 30, 2020. Studies were included if they involved patients 16 years and older, where laryngeal US was compared to laryngoscopy for TVFI. Studies were excluded if there were insufficient data to compute a sensitivity/specificity table after attempting to contact the authors. Case reports, and case series were also excluded. The initial search returned 1357 citations. Of these, 109 were selected for review utilizing the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Thirty citations describing 6033 patients were included in the final meta-analysis. A bivariate random effects meta-analysis was performed, revealing a pooled sensitivity for laryngeal US of 0.95 (95% confidence interval [CI] 0.88-0.98), a specificity of 0.99 (95% CI 0.97-0.99), and a diagnostic odds ratio of 1328.2 (95% CI 294.0-5996.5). The area under the curve of the hierarchical summary receiver operating characteristic curve was 0.99 (95% CI 0.98-1.00). Laryngeal US demonstrates high sensitivity and specificity for detecting VFI in the hands of clinicians directly providing care to patients.

Adjustments of non-invasive ventilation and mechanically assisted cough by combining ultrasound imaging of the larynx with transnasal fibre-optic laryngoscopy: a protocol for an experimental study

INTRODUCTION

Application of non-invasive positive airway pressure may provoke laryngeal responses that obstruct the airways, especially in patients with disturbed laryngeal control. To control and adjust for this, transnasal fibre-optic laryngoscopy (TFL) is used to visualise laryngeal movements during therapeutic interventions. Being an invasive procedure, this may be unpleasant for patients. The aim of this study is to evaluate if ultrasound (US) imaging of the larynx may be used as an alternative less invasive diagnostic tool for evaluating the upper airway responses to non-invasive ventilation (NIV) and mechanical insufflation-exsufflation (MI-E).

METHODS AND ANALYSIS

This protocol presents an experimental cross-sectional study of a novel method to study laryngeal responses in adult healthy volunteers (n=30). The participants will be assessed with simultaneous TFL and laryngeal US imaging (anterior and lateral approaches) during NIV and MI-E therapy. Additionally, airflow and pressure signals will be registered during the procedures. The primary outcome is whether laryngeal US is a feasible method to study laryngeal responses and, if so, to compare the laryngeal responses visualised with TFL and US. The participants' perception of the examinations will be recorded. Secondary outcomes include airflow curve shapes and calculated ventilation volumes during the interventions.

ETHICS AND DISSEMINATION

The study has been approved by The Regional Committee for Medical Research Ethics in Norway, and registered in ClinicalTrials.gov. Results will be disseminated through peer-reviewed journals, presentation of scientific abstracts at international medical conventions and oral presentations in relevant medical conventions.

TRIAL REGISTRATION NUMBER

NCT04586855.

Radiological correlates of vocal fold bowing as markers of Parkinson's disease progression: A cross-sectional study utilizing dynamic laryngeal CT

OBJECTIVE

To determine whether arytenoid cartilage position and dynamics change with advancing duration and severity (as graded by MDS-UPDRS part III scores) in Parkinson's disease, in a cross-sectional study design, we performed laryngeal four-dimensional computed tomography (4D-CT) in people with Parkinson's disease and controls.

METHODS

31 people with Parkinson's disease covering a range of disease duration and severity and 19 controls underwent laryngeal 4D-CT whilst repeatedly vocalizing. We measured on each CT volume the glottic area (GA), inter-arytenoid distance (IAD), IAD-Area index (IAI) and arytenoid cartilage velocity ([Formula: see text]).

RESULTS

People with Parkinson's disease had reductions in the mean/effective minimum IAD when compared to controls, while mean/effective minimum GA and mean/effective maximum IAI were increased. Arytenoid cartilage velocities showed no difference. On Spearman correlation analyses, advancing disease duration and severity of PD showed moderately strong and significant correlations with increasing mean/effective minimum GA, increasing mean/effective maximum IAI and decreasing effective minimum IAD. Linear mixed models which considered the effects of intra and inter-individual variation showed that both disease duration (b = -0.011, SEb = 0.053, 95% CI [-0.022, 0], t(27) = -2.10, p = 0.045) and severity (b = -0.069, SEb = 0.032, 95% CI [-0.14,-0.0039], t(27) = -2.17, p = 0.039) were significant predictors for IAD, and also for transformed values of the GA and IAI.

CONCLUSIONS

There are progressive alterations in phonatory posturing as Parkinson's disease advances. The increases in GA despite reductions in IAD are concordant with prior observations of vocal fold bowing. Our study provides a basis for using laryngeal 4D-CT to assess disease progression in Parkinson's disease.

Ultrasound prediction for vocal cord dysfunction in patients scheduled for anterior cervical spine surgeries: a prospective cohort study

Prediction of vocal cord dysfunction is essential after anterior cervical spine surgeries. This study aimed to detect the validity of transcutaneous laryngeal ultrasonography by both anterior and novel lateral approaches for prediction of vocal cord edema and paralysis after anterior cervical spine surgeries. A prospective cohort study conducted on 90 patients scheduled for anterior cervical spine surgeries underwent consecutive pre and postoperative vocal cord examination for edema and paralysis by both anterior and lateral approaches laryngeal ultrasonography. Rigid laryngoscopy was the standard confirmatory tool. For postoperative vocal cord edema, the anterior ultrasonography approach diagnostic sensitivity = 88.2%, specificity = 78.9% with PPV = 78.9% and NPV = 88.2% and the novel lateral ultrasonography approach diagnostic sensitivity = 88.2%, specificity = 94.7% with PPV = 93.75% and NPP = 90%. While for paralysis, the anterior ultrasonography approach diagnostic sensitivity = 86.7%, specificity = 85.7% with PPV = 81.25% and NPV = 90% and the novel lateral ultrasonography approach diagnostic (sensitivity, specificity with PPV and NPP) = 100%. The diagnostic accuracy of the novel lateral approach was more correlated to rigid laryngoscopy (91.7% and 100%) compared to anterior approach for vocal cord edema and paralysis (83.3% and 80.6%). Overall incidence of vocal cord paralysis was 16.6%. Risk of vocal cord paralysis was statistically significant more in female, multiple disc herniation, lower and mixed disc levels, Langenbeck retractor, cage and plate and duration of surgery ≥ 1.5 h. Transcutaneous Laryngeal ultrasound is a valid comfortable tool for prediction of vocal cord edema and paralysis after anterior cervical spine surgeries with superiority of the novel lateral over anterior approach.

A prospective study comparing the midline and lateral trans-laryngeal ultrasonography approaches in vocal cord assessment before and after thyroid and neck surgeries

INTRODUCTION

It is unclear if placing an ultrasound probe along each thyroid cartilage lamina (i.e. the lateral approach) can improve vocal cord (VC) visualization over in the midline (i.e. the midline approach) in trans-larygeal ultrasonography (TLUSG). This study compared VC visualization rates and diagnostic accuracy between the two approaches.

METHODS

Consecutive patients undergoing surgery had their VCs assessed by the two TLUSG approaches and flexible laryngoscopy within the same session. VC visualization rates and diagnostic accuracy of each approach were calculated and compared.

RESULTS

Ninety patients (or 180 VCs) were analyzed. The lateral approach had significantly better overall VC visualization rate than the midline approach (93.3% vs. 82.2%, p=<0.001), especially for males (75.0% vs. 33.3%, p = 0.002). Both approaches had comparable accuracy (100% vs. 99.4%).

CONCLUSIONS

The lateral approach should be preferred because of the significantly better VC visualization rate and comparable accuracy to the midline approach.

Upper Airway Assessment and Responses During Mechanically Assisted Cough

When the ability to cough is impaired, secretion clearance may be assisted and augmented with mechanical insufflation-exsufflation (MI-E). In some individuals, the efficacy of MI-E may be hampered by counterproductive upper airway reactions, where the airways close in response to positive pressures. To fully utilize the therapeutic potential inherent in the MI-E technology, we need a better understanding of the pathophysiology behind these untoward reactions. There is increasing interest in monitoring and measuring upper airway responses to MI-E and how such information can be used to optimize MI-E settings. The purpose of this narrative review is to increase the theoretical understanding of the larynx as a respiratory organ, summarize the current literature in the area, and provide insight into how this knowledge can affect current clinical practice.

Consensus statement by the American Association of Clinical Endocrinology (AACE) and the American Head and Neck Society Endocrine Surgery Section (AHNS-ES) on Pediatric Benign and Malignant Thyroid Surgery

OBJECTIVES

To provide a clinical disease state review of recent relevant literature and to generate expert consensus statements regarding the breadth of pediatric thyroid cancer diagnosis and care, with an emphasis on thyroid surgery. To generate expert statements to educate pediatric practitioners on the state-of-the-art practices and the value of surgical experience in the management of this unusual and challenging disease in children.

METHODS

A literature search was conducted and statements were constructed and subjected to a modified Delphi process to measure the consensus of the expert author panel. The wording of statements, voting tabulation, and statistical analysis were overseen by a Delphi expert (J.J.S.).

RESULTS

Twenty-five consensus statements were created and subjected to a modified Delphi analysis to measure the strength of consensus of the expert author panel. All statements reached a level of consensus, and the majority of statements reached the highest level of consensus.

CONCLUSION

Pediatric thyroid cancer has many unique nuances, such as bulky cervical adenopathy on presentation, an increased incidence of diffuse sclerosing variant, and a longer potential lifespan to endure potential complications from treatment. Complications can be a burden to parents and patients alike. We suggest that optimal outcomes and decreased morbidity will come from the use of advanced imaging, diagnostic testing, and neural monitoring of patients treated at high-volume centers by high-volume surgeons.

Consensus Statement by the American Association of Clinical Endocrinology (AACE) and the American Head and Neck Society Endocrine Surgery Section (AHNS) on Pediatric Benign and Malignant Thyroid Surgery

OBJECTIVES

To provide a clinical disease state review of recent relevant literature and to generate expert consensus statements regarding the breadth of pediatric thyroid cancer diagnosis and care, with an emphasis on thyroid surgery. To generate expert statements to educate pediatric practitioners on the state-of-the-art practices and the value of surgical experience in the management of this unusual and challenging disease in children.

METHODS

A literature search was conducted and statements were constructed and subjected to a modified Delphi process to measure the consensus of the expert author panel. The wording of statements, voting tabulation, and statistical analysis were overseen by a Delphi expert (J.J.S.).

RESULTS

Twenty-five consensus statements were created and subjected to a modified Delphi analysis to measure the strength of consensus of the expert author panel. All statements reached a level of consensus, and the majority of statements reached the highest level of consensus.

CONCLUSION

Pediatric thyroid cancer has many unique nuances, such as bulky cervical adenopathy on presentation, an increased incidence of diffuse sclerosing variant, and a longer potential lifespan to endure potential complications from treatment. Complications can be a burden to parents and patients alike. We suggest that optimal outcomes and decreased morbidity will come from the use of advanced imaging, diagnostic testing, and neural monitoring of patients treated at high-volume centers by high-volume surgeons.

Application of Transcutaneous Laryngeal Ultrasonography in the Diagnosis of Vocal Fold Polyps

The aim of this study was to explore the value of transcutaneous laryngeal ultrasonography in the diagnosis of vocal fold polyps. From December 2016 to June 2019, 87 patients with vocal fold polyps diagnosed pathologically in the Otolaryngology Head and Neck Surgery Department of the Second Affiliated Hospital of Xi'an Jiaotong University were enrolled and examined by electronic laryngoscopy and percutaneous laryngeal ultrasound on the same day before operation. To observe the effect of calcification length as a percentage of thyroid cartilage at the glottic level on vocal fold display, the characteristics of ultrasound images of vocal fold polyps and the value of transcutaneous laryngeal ultrasonography in the diagnosis of vocal fold polyps were assessed. Among 87 patients, the calcification rate of thyroid cartilage at the glottic level was 33.3%. The differences in calcification rate and percentage of calcification length between males and females were statistically significant. The rate of detection of vocal folds decreased gradually with an increase in calcification length percentage. Imaging features of vocal fold polyps were hypo-echoic with a clear boundary and regular shape. The detection rates for circular and non-circular polyps were 92.0% and 70.6%. Ultrasound was more likely to detect circular than non-circular polyps; however, the difference was not significant. Transcutaneous laryngeal ultrasonography can identify the morphology and location of vocal fold polyps and is non-invasive and highly accurate. Therefore, it has the potential to be an effective supplement to laryngoscopy for initial screening and post-operative review of vocal fold polyps.

Laryngeal Evaluation during the COVID-19 Pandemic: Transcervical Laryngeal Ultrasonography

The novel coronavirus disease (COVID-19), caused by the SARS-CoV-2 virus, has quickly become a global pandemic since its initial outbreak in China in late 2019. Institutions are faced with the challenge of upholding the standard of care while maintaining safety for health care personnel and patients. Due to the common performance of aerosol-generating endoscopic procedures in the upper respiratory tract, otolaryngologists are at uniquely high risk for potential infection. When possible, alternative diagnostic and treatment strategies should be pursued. For patients suspected of having functional laryngeal abnormalities, transcervical laryngeal ultrasound provides a rapid and noninvasive evaluation of vocal fold motion to inform decisions about safety of feeding, airway, and progression of care.

Transcutaneous Laryngeal Ultrasonography for the Assessment of Laryngeal Function After Thyroidectomy: A Review

OBJECTIVE

This review set out to examine the applicability of transcutaneous laryngeal ultrasonography (TLUSG) for the assessment of laryngeal function after thyroidectomy.

METHODS

An integrative review of the literature was performed using Medline/PubMed, LILACS, and SciELO databases. The methodological quality of the studies was analyzed using the appraisal tool for cross-sectional studies.

RESULTS

All 8 included articles investigated laryngeal function with regard to the risk of vocal fold immobility after thyroidectomy. The results regarding the diagnostic power of TLUSG for this assessment are controversial, and there is a tendency to use this examination as a screening procedure for subsequent confirmation by flexible laryngoscopy.

CONCLUSIONS

Transcutaneous laryngeal ultrasonography is a viable, noninvasive, and useful tool to assess laryngeal function after thyroidectomy, but current available evidence suggests that it does not replace flexible laryngoscopy for the diagnosis of vocal fold immobility.

Imaging the Vocal Folds: A Feasibility Study on Strain Imaging and Elastography of Porcine Vocal Folds

Vocal folds are an essential part of human voice production. The biomechanical properties are a good indicator for pathological changes. In particular, as an oscillation system, changes in the biomechanical properties have an impact on the vibration behavior. Subsequently, those changes could lead to voice-related disturbances. However, no existing examination combines biomechanical properties and spatial imaging. Therefore, we propose an image registration-based approach, using ultrasound in order to gain this information synchronously. We used a quasi-static load to compress the tissue and measured the displacement by image registration. The strain distribution was directly calculated from the displacement field, whereas the elastic properties were estimated by a finite element model. In order to show the feasibility and reliability of the algorithm, we tested it on gelatin phantoms. Further, by examining ex vivo porcine vocal folds, we were able to show the practicability of the approach. We displayed the strain distribution in the tissue and the elastic properties of the vocal folds. The results were superimposed on the corresponding ultrasound images. The findings are promising and show the feasibility of the suggested approach. Possible applications are in improved diagnosis of voice disorders, by measuring the biomechanical properties of the vocal folds with ultrasound. The transducer will be placed on the vocal folds of the anesthetized patient, and the elastic properties will be measured. Further, the understanding of the vocal folds’ biomechanics and the voice forming process could benefit from it.

Vocal Cord Palsies Missed by Transcutaneous Laryngeal Ultrasound (TLUSG): Do They Experience Worse Outcomes?

INTRODUCTION

Transcutaneous laryngeal ultrasound (TLUSG) is an innovative, non-invasive tool in detecting post-thyroidectomy vocal cord palsy (VCP). However, TLUSG failed to detect about 6-15% laryngoscopic examination (LE)-confirmed VCP. It is unclear whether the outcome of patients with VCP missed by TLUSG [false negative (FN)] is different from those with VCP diagnosed by TLUSG [true positive (TP)]. Therefore, this study aimed to compare the clinical outcome and prognosis between patients with FN results and TP results.

METHODS

Over 46 months, all consecutive patients undergoing thyroidectomy or endocrine-related neck procedure were recruited. They underwent pre-operative and post-operative voice assessments on symptoms, voice-specific questionnaire [voice handicap index questionnaire (VHI-30)], TLUSG and LE. For patients with post-operative vocal cord palsy, reassessment LE would be arranged at second, fourth, sixth and twelfth months post-operatively until VCP recovered.

RESULTS

In total, 1196 patients, including 74 post-thyroidectomy VCP, were recruited. For those with assessable vocal cords (VC), 58 VCP were correctly diagnosed by TLUSG (TP) and 10 VCP were missed by TLUSG (FN). Sensitivity and specificity of detecting a VCP by TLUSG were 85.3% and 94.7%, respectively. VHI-30 score was significantly increased after operation in TP group [31 (range - 6-105), p < 0.001] but not in FN group [20 (14-99), p = 0.089]. Comparing to TP group, VCP recovered earlier (69 vs. 125 days, p < 0.001) and less patients suffered from permanent VCP in patients with FN results. (34.5% vs. 0.0%, p = 0.027).

CONCLUSION

The VCP missed by TLUSG had a milder course of disease. Early recovery of VC function and non-permanent palsy were expected.

Functional analysis of vocal folds by transcutaneous laryngeal ultrasonography in patients undergoing thyroidectomy

BACKGROUND

Transcutaneous laryngeal ultrasound (TCLUS) can assess Vocal folds (VF) by subjectively identifying mobility or objectively by calculating vocal fold displacement velocity (VFDV). Optimal diagnostic approach (subjective assessment, VFDV estimation or a combination of both) is unresolved; hence, we conducted this prospective study in patients undergoing thyroidectomy.

METHOD

Two anaesthetists performed TCLUS pre- and post-operatively for functional assessment of 200 VFs on 100 patients. Their findings were compared with pre-operative flexible laryngoscope (FL) performed by surgeons and with post-operative C-Mac video laryngoscope (C-Mac VL) by another independent anaesthetist. Correlation between FL and TCLUS findings and inter-rater agreement between TCLUS findings of both anaesthetists was analysed. Decision curve analysis (DCA) was performed to compare clinical benefit of hoarseness, subjective VF movement, VFDV, and combined assessment for detecting disabled VFs.

RESULTS

We found good correlation between VF mobility on TCLUS and FL (Spearman's r = 0.93, P < 0.0001) as well as C-Mac VL (Spearman's r = 0.83, P < 0.0001) with excellent inter-rater agreement between both anaesthetists. DCA showed combined assessment to have marginally higher clinical benefit than other diagnostic approaches at intermediate threshold probabilities while its benefit was similar to subjective evaluation at higher threshold probabilities.

CONCLUSION

Provided achievement of optimal acoustic window, TCLUS can reliably assess disabled VFs with FL reserved for their confirmation or doubtful cases. Subjective assessment of VF mobility should suffice in most cases with additional VFDV estimation reserved pre-operatively for situations with higher risk of VFs disability, and post-operatively when subjective VF assessment findings are discordant from pre-operative status.