Comparison of diffusion ranges at different local anesthetic volumes during superior laryngeal nerve block.

OBJECTIVES: Ultrasound-guided superior laryngeal nerve (SLN) block is a practical and painless approach to avoid the hemodynamic stress response during endotracheal intubation and relieve sore throat after laryngeal surgery. The main purpose of this study was to establish an optimal dosage of local anesthetic when performing SLN block to help anesthetists balance analgesia and side effects. METHODS: Twenty fresh larynx specimens were obtained immediately after resection and then injected with 2-, 3-, 4-, or 5- mL of a lidocaine-blue dye mixture at bilateral SLN puncture sites. Superficial areas of deposited blue dye were measured. Dye leakage and surrounding dyed tissue were recorded. Another 40 patients were included in the ultrasound investigation. Distances between the internal branch of the SLN (iSLN) and adjacent structures were calculated. RESULTS: The dye spread area was greater with the administration of larger doses, especially to the visceral space. A 2- or 3-mL injection of local anesthetic was sufficient to infiltrate the SLN gap. A higher incidence of dye leaking out of the thyrohyoid membrane and anterior epiglottis space was observed; furthermore, there was substantially more dyed hyoid/thyroid cartilage with 4 and 5 mL of injected dye mixture than 2 mL. There was no significant difference between the specimen and ultrasound measurements of for length of iSLN-adjacent structures. CONCLUSIONS: In the Chinese population, 2- or 3- mL of local anesthetic is a safe dose during SLN block. A larger volume could overflow from the cavity to cause complications. The thyrohyoid membrane combined with the superior laryngeal artery is a reliable target for positioning the iSLN during ultrasound-guided regional anesthesia.

The Effect of Thyroid Surgery on the Accuracy of Palpation-Based Cricothyroid Membrane Identification in Female Patients: A Prospective Observational Cohort Study.

Background and Objectives: This study examined how a history of thyroid surgery impacts the precision of cricothyroid membrane (CTM) identification through palpation (validated by ultrasound) in female patients visiting the operating room for surgeries unrelated to neck procedures. Materials and Methods: This prospective observational cohort study enrolled adult female patients undergoing elective non-neck surgery, dividing them into control (no thyroid surgery history; n = 40) and experimental (with thyroid surgery history; n = 40) groups. CTM identification was performed by palpation and confirmed via ultrasound. Results: There were no significant differences between two groups in the demographic characteristics of the patients. The success rate and accuracy of CTM identification through palpation were significantly higher in the control group compared to the experimental group (90% vs. 42.5%, respectively; p < 0.001). For female patients with a history of thyroid surgery, the sensitivity of successful CTM palpation was 42.5%, and the specificity was 10%. These figures are based on the calculated true positives (17), false positives (36), true negatives (4), and false negatives (23). Conclusions: Thyroid surgery history in female patients may hinder the accurate palpation-based identification of the CTM, suggesting a need for enhanced clinical practices and considerations during airway management training.

Thyroid cartilage infiltration in advanced laryngeal cancer: prognostic implications and predictive modelling.

Objective: Detection of laryngeal cartilage invasion is of great importance in staging of laryngeal squamous cell carcinoma (LSCC). The role of prognosticators in locally advanced laryngeal cancer are still widely debated. This study aimed to assess the impact of volume of thyroid cartilage infiltration, as well as other histopathologic variables, on patient survival. Materials and methods: We retrospectively analysed 74 patients affected by pT4 LSCC and treated with total laryngectomy between 2005 and 2021 at the Department of Otorhinolaryngology - Head and Neck Surgery of the University of Brescia, Italy. We considered as potential prognosticators histological grade, perineural (PNI) and lympho-vascular invasion (LVI), thyroid cartilage infiltration, and pTN staging. Pre-operative CT or MRI were analysed to quantify the volume of cartilage infiltration using 3D Slicer software. Results: The 1-, 3-, and 5-year disease free survivals (DFS) were 76%, 66%, and 64%, respectively. Using machine learning models, we found that the volume of thyroid cartilage infiltration had high correlation with DFS. Patients with a higher volume (>670 mm3) of infiltration had a worse prognosis compared to those with a lower volume. Conclusions: Our study confirms the essential role of LVI as prognosticator in advanced LSCC and, more innovatively, highlights the volume of thyroid cartilage infiltration as another promising prognostic factor.

External laryngotracheal trauma: a case series and an algorithmic management strategy.

OBJECTIVES: External laryngotracheal trauma (ELT), blunt or penetrating, is a rare but potentially life-threatening injury. Immediate care in the emergency department can be challenging because it requires managing a potentially unstable airway and may have associated vascular injuries with massive bleeding. Here, we look at the details of injury, treatment measures, and outcomes in patients following ELT. METHODS: We retrospectively analyzed 22 patients treated at our center for ELT from January 2005 up to December 2021 with varying grades of injury. We looked at their status at presentation, management strategy and functional status. RESULTS: In our report, we include 18 men and 4 women having varying Schaefer injury grades. Eight patients had tracheostomy at presentation and eight had vocal fold immobility. Two patients were treated endoscopically, 12 had open surgery and 8 received no treatment. Of the patients undergoing open surgery, thyroid cartilage fracture was seen in 9 patients, thyroid plus cricoid fracture and cricotracheal separation were seen in 3 patients each. All patients were safely decannulated and spontaneous recovery of vocal cord palsy was seen in some patients. CONCLUSION: The success of managing ELT relies on fast decision-making, correct patient evaluation, securing the airway and maintaining the hemodynamic stability. Early surgical intervention must be aimed at optimally treating the larygotracheal injuries to prevent long-term disastrous consequences.

Assessment of thyroid cartilage ossification pattern in cancer patients: A suggestion of active ossification by tumor progression.

BACKGROUND: Ossified cartilage is much more susceptible to cancer infiltration, but the reason remains unknown, and the relationship between the ossification pattern and cancer infiltration has not been studied. METHODS: The presence of thyroid cartilage ossification, cancer infiltration, ossification pattern (usual: direction from inferior to superior; unusual: other than the usual pattern), and distance between cancer and ossified cartilage were evaluated in laryngectomy specimens. RESULTS: There were 28 and 27 cases of usual and unusual patterns, respectively. There was no association between ossification pattern and cancer infiltration. However, the distance between the ossified area and cancer cells was greater in the usual pattern than in the unusual pattern (p = 0.006). And the usual pattern was more frequently observed in cases with a distance >1 mm than in cases with cancer infiltration or a distance ≤1 mm (p = 0.004). CONCLUSION: These results suggest the possibility of an active ossification due to tumor progression.

Chondrolaryngoplasty.

Chondrolaryngoplasty is a surgical procedure that reduces the prominence of the thyroid notch. Although frequently performed on transgender (man to woman) women, anyone wishing to reduce the prominence of their thyroid notch for aesthetic purposes may consider undergoing a chondrolaryngoplasty. Direct visualization of the vocal cords with flexible laryngoscopy and intraoperative needle localization of the anterior commissure directs the extent of resection, helps increase safety, and avoids devastating postoperative voice complications. This procedure can be safely performed in combination with other facial feminization surgeries.

Post-pubertal developmental trajectories of laryngeal shape and size in humans.

Laryngeal morphotypes have been hypothesized related to both phonation and to laryngeal pathologies. Morphotypes have not been validated or demonstrated quantitatively and sources of shape and size variation are incompletely understood but are critical for the explanation of behavioral changes (e.g., changes of physical properties of a voice) and for therapeutic approaches to the larynx. This is the first study to take this crucial step and results are likely to have implications for surgeons and speech language pathologists. A stratified human sample was interrogated for phenotypic variation of the vocal organ. First, computed tomography image stacks were used to generate three-dimensional reconstructions of the thyroid cartilage. Then cartilage shapes were quantified using multivariate statistical analysis of high dimensional shape data from margins and surfaces of the thyroid cartilage. The effects of sex, age, body mass index (BMI) and body height on size and shape differences were analyzed. We found that sex, age, BMI and the age-sex interaction showed significant effects on the mixed sex sample. Among males, only age showed a strong effect. The thyroid cartilage increased in overall size, and the angulation between left and right lamina decreased in older males. Age, BMI and the age-height interaction were statistically significant factors within females. The angulation between left and right lamina increased in older females and was smaller in females with greater BMI. A cluster analysis confirmed the strong age effect on larynx shape in males and a complex interaction between the age, BMI and height variables in the female sample. The investigation demonstrated that age and BMI, two risk factors in a range of clinical conditions, are associated with shape and size variation of the human larynx. The effects influence shape differently in female and male larynges. The male-female shape dichotomy is partly size-dependent but predominantly size-independent.

Morphometric Analysis and Observer Perceptions Following Transvestibular Chondrolaryngoplasty.

OBJECTIVES: To assess novel morphometric measurement strategies and observer perception ratings as potential metrics for evaluating gender-affirming transvestibular chondrolaryngoplasty in reducing contour protrusion of the neck. METHODS: High-resolution preoperative and 3-month postoperative photographs of a pilot series of 10 patients (n = 10) who underwent endoscopic transvestibular chondrolaryngoplasty were collected. Morphometric measurements of "light reflex" and lateral view thyroid protrusion angles of the neck contours were analyzed. Pre- and postoperative photographs were presented in random order in a survey to 17 untrained judges and rated on perceived masculinity/femininity and thyroid notch protrusion on a 7-point scale. A pre- to postoperative change in morphometric angles and subjective ratings was assessed using paired t-tests and Wilcoxon signed-rank tests. RESULTS: Mean light reflex angles were reduced after surgery from 78.6° to 40.5° in the anterior neutral view (P = .0003), from 45.2° to 24.4° in the anterior extended view (P = .003), and from 7.03° to 4.32° in the lateral view (P = .006). Median survey ratings of neck photographs were improved after surgery, from 4 to 3 in gender perception toward more feminine perception (P < .0001) and from 4 to 2 in thyroid protrusion toward less protrusive perception (P < .0001). CONCLUSIONS: Morphometric analysis in anterior and lateral views as well as subjective gender perception and contour protrusion measures following feminization chondrolaryngoplasty by endoscopic transvestibular scarless approach demonstrate encouraging possibilities as outcome evaluation measures for chondrolaryngoplasty.

Chondrolaryngoplasty with Endoscopic Direct Visualization of the Vocal Cords: Demonstration of Technique.

SUMMARY: Chondrolaryngoplasty is a surgical procedure that reduces a prominent thyroid cartilage. Demand for chondrolaryngoplasty has significantly increased over recent years in transgender women and nonbinary individuals and has been shown to alleviate gender dysphoria and improve quality of life. When performing chondrolaryngoplasty, surgeons must carefully balance the desire for maximal cartilage reduction with the potential for damage to surrounding structures (ie, the vocal cords) that may result because of overaggressive or imprecise resection. Our institution has adopted the technique of direct vocal cord endoscopic visualization using a flexible laryngoscope for increased safety. Briefly, surgical steps include dissection and preparation for translaryngeal needle placement, endoscopic visualization of the needle placed above the level of the vocal cords, marking of the corresponding level, and resection of the thyroid cartilage. The following article and supplemental video provide further detailed descriptions of these surgical steps as a resource for training and technique refinement.

Chondrosarcoma of the thyroid cartilage: surgical management of a rare case.

Laryngeal malignancy encompasses about 1% of all cancers. Chondrosarcoma in the head and neck region represents about 0.1% of head and neck malignancies. Typical presenting symptoms relate to the anatomical location of these tumours and include dysphonia, inspiratory stridor, dysphagia, odynophagia or a neck mass. Benign and malignant cartilaginous cancers of the larynx have been described, and preoperative diagnosis can be difficult. Our report highlights the surgical management of a male patient in his 50s with chondrosarcoma of the thyroid cartilage.

Laryngeal Framework Surgical Anatomy: A Radiological Study.

PURPOSE: Awareness of variations in laryngeal anatomy among different age and gender groups is crucial during laryngeal framework surgery. The aim of this study is to demonstrate the relationship between gender and laryngeal radiologic morphometrics among different age groups and the applicability of important anatomical landmarks of laryngeal surgery. METHODS: Laryngeal images of 180 adult patients older than 18 years of age were obtained by computed tomography and assessed. A total of 11 measurements of important laryngeal landmarks were taken from the patients' computed tomography images. Results were subgrouped according to gender and age, and these groups were compared for each measurement. RESULTS: The majority of laryngeal measurements obtained in the study were higher in males than females, with the exception of the interlaminar angle. The mean interlaminar angle value was 88.27°± 14.99 for males and 103.04°± 14.81 for females (P <0.005). The distance from the anterior commissure to the inferior border of the thyroid cartilage was 10.46 ± 2.5 mm for males and 7.72 ± 1.9 mm for females. The anterior commissure locates slightly higher than the midpoint of the distance from the thyroid notch to the thyroid inferior border. The shortest distance between the muscular process of the arytenoid cartilage and the thyroid cartilage was found to be 9.60 ± 3.47 mm for males and 7.72 ± 2.33 mm for females (P <0.001). CONCLUSION: Observation of obvious diversities in the size and distance of the important laryngeal structures between the gender groups is an important factor to be considered for successful laryngeal framework surgery. Also, using the midpoint of the thyroid cartilage as a landmark for anterior commissure is a practical method during surgery, especially for thyroplasty.

Chondrosarcoma of the Thyroid Cartilage Successfully Treated With Partial Resection of the Thyroid Cartilage.

Chondrosarcoma of the thyroid cartilage is a sporadic disease with nonspecific clinical presentation. Smooth swelling of the supraglottic area should arouse suspicion of possible pathology. In addition to laryngoceles, which usually do not have a significant impact, otolaryngologists should consider chondrosarcoma of the thyroid cartilage and indicate computed tomography (CT). Late diagnosis leads to worse prognosis, particularly worse voice after more extensive surgery, need for tracheostomy, and worse survival from higher degree chondrosarcomas.

Thyroid Cartilage Compression Causing Bow Hunter's Syndrome.

OBJECTIVES AND METHODS: We report a unique case of Bow Hunter's syndrome with a dominant aberrantly coursing right vertebral artery (VA), presenting with persistent dizziness and syncope despite previous decompressive surgery at vertebral levels C5-C6. RESULTS: Re-evaluation with computed tomography-scan during provocation of dizziness by neck rotation revealed compression of the right VA at level C6 from against the ipsilateral posterior border and superior cornu of the thyroid cartilage. Laryngoplasty resulted in complete resolution of symptoms. CONCLUSION: This extremely rare cause of Bow's Hunter's syndrome should be considered, especially in refractory cases after neurosurgical decompression, and surgical management is straightforward and successful.

A New Technique for Chondrolaryngoplasty in Patients Assigned Female at Birth.

BACKGROUND: Chondrolaryngoplasty is a classical facial feminization surgery for transgender women. In recent years, however, an increasing number of patients assigned female at birth are seeking chondrolaryngoplasty for esthetic purposes. Traditional chondrolaryngoplasty can no longer cope with problems of the growing group whose leading cause of laryngeal prominence differs from the transgender population. METHODS: A modified technique is designed as a supplement to the classical procedure. After the cartilage reduction process, paired platysma flaps are raised and advanced successively, resulting in an overlapped area over the thyroid notch, to further camouflage the thyroid prominence. To evaluate the efficiency of the new technique, a retrospective survey of 34 patients (5 men and 29 women) who underwent the surgery from 2016 to 2021 was performed, via a 5-point Likert scale including 7 questions. Physician assessment was also accomplished to provide an extra estimation. Complications were followed up and analyzed to evaluate the safety of modified surgery as well. RESULTS: Although only half of the patients graded prominence changes more than "moderately changed," as many as 75.0% of them still expressed "completely satisfied" or "satisfied very much" with the outcome. Similarly, physician assessment indicated a satisfactory result in appearance improvement. No severe and irreversible complications occurred after surgery, but lasting scar-related issues were reported by 4 patients and should be paid more attention to. CONCLUSIONS: Generally speaking, the new technique is both safe, efficient, and satisfying for most patients, especially ones assigned females at birth with esthetic demand.

Comparison of EMG amplitudes recorded by ipsilateral and contralateral electrodes placement during using trans-thyroid cartilage recording method in thyroid surgery.

Objectives: The feasibility and reliability of trans-thyroid cartilage EMG recording method (TCERM) during intraoperative monitoring (IONM) of the recurrent laryngeal nerve (RLN) in thyroid surgery have been established. This study compared two different recording electrode placements on the ipsi-lateral and contra-lateral lamina of the thyroid cartilage (TC). Methods: Fifty consecutive patients undergoing total thyroidectomy with 100 RLNs at risk were enrolled. Two paired subdermal needle electrodes were inserted into the subperichondrium of the bilateral TC lamina to record electromyography (EMG) signals. The channel leads from the TC electrodes were connected to the patient interface with two different modes. In A-mode, the electrode leads were placed ipsi-laterally, and channel 1 monitored the left RLN and channel 2 monitored the right RLN respectively. In B-mode, the electrode leads were placed contra-laterally, and channels 1 and 2 simultaneously monitored the same side of the RLN. The amplitudes of four EMG signals (V1-R1-R2-V2) recorded by A-mode and B-mode were compared. Results: All EMG amplitudes of V1-R1-R2-V2 signals recorded with B-mode were all above 500µV and significantly higher than those with A-mode (p<0.001). No false loss of signal, electrode dislodgement, or needle-related complications were noted during IONM. Postoperatively, all patients had symmetrical vocal cord movement. Lower EMG amplitudes were observed in older and male patients. Histopathology and laterality showed no significant differences in EMG amplitude. Conclusion: During using TCERM in thyroid surgery, the recording electrodes should be placed contra-laterally on the TC lamina. This approach ensures high and stable EMG signals, which are important for high-quality IONM of the RLN.

De Novo Extramedullary Plasmacytoma of Thyroid Cartilage.

ABSTRACT: Myeloma involving the laryngeal cartilage is rare, whereas extramedullary plasmacytoma involving only the thyroid cartilage is even rarer. No case of de novo extramedullary plasmacytoma involving thyroid cartilage has been published so far. Hence, it was a diagnostic challenge for clinicians, radiologists, and pathologists. Here, we presented a case of a 61-year-old man who had fixed right laryngeal swelling. After 18 F-FDG PET/CT, biopsy, and myeloma workup, it was found to be plasmacytoma involving the right thyroid cartilage lamina. This case highlighted the rarity of this presentation and the importance of keeping in mind this differential to lead toward diagnosis.

Laryngeal function-preserving of frontolateral vertical partial laryngectomy (FLVPL) for selected T4a glottic cancer with thyroid cartilage invasion adherence to the anterior commissure: an innovative attempt.

OBJECTIVE: To evaluate the feasibility and efficacy in selected T4a glottic cancer (thyroid cartilage invasion adherence to the anterior commissure) treated with frontolateral vertical partial laryngectomy (FLVPL) and laryngeal framework reconstruction using titanium mesh. METHODS: Six patients with the limited T4a glottic cancer with thyroid cartilage destruction adherence to the anterior commissure, underwent FLVPL from 2009 to 2016 in Sun Yat-Sen University Cancer Center. All patients were followed up postoperatively. RESULTS: All patients comprised radical tumor resection and favorable functional outcomes, and no aspiration and laryngeal stenosis were observed. According to postoperative pathology, four patients should go through postsurgical radiotherapy with a mean dose of 66 Gy. But one of them refused to undergo postoperative radiotherapy, who observed local recurrence in postcricoid area underwent total laryngectomy (TL) and ipsilateral selected neck dissection in post-surgery two year. During follow-up period, all patients were still alive, and five patients without local recurrence and distant metastases. CONCLUSION: FLVPL and laryngeal framework reconstruction using titanium mesh is one viable surgical procedure to obtain adequate oncologic and functional outcomes.

Chondrolaryngoplasty.

Chondrolaryngoplasty is a well-described surgical procedure most commonly performed as part of facial feminization surgery for transgender patients with a diagnosis of gender dysphoria. A complete understanding of relevant neck anatomy and laryngeal function is critical to optimizing surgical outcomes. The overall goal of the procedure is to maximally reduce the thyroid cartilage prominence while preserving laryngeal integrity and minimizing the risk of external scarring. Among available approaches, the bronchoscopic-assisted technique with intraoperative needle localization has been demonstrated to reliably lead to safe and effective surgical outcomes while minimizing the risk of postoperative complications.