A Chaotic Approach to Glottal Gap Voice.

OBJECTIVE: Airway glottic insufficiency, or glottal gap, may lead to a breathy voice quality. It is hypothesized that a glottal gap may be a source of nonlinearity in speech production. This study aims to gain a chaotic and acoustic profile of glottal gap voice provided by phonation of excised larynges subjected to the insertion of a metal shim in the posterior glottis. STUDY DESIGN: Nonrandomized quasi-experimental study. METHODS: Posterior glottal gap varied from 0 to 3.5 mm in 0.5 mm intervals. Each treatment was investigated independently in a sample population of eight excised canine larynges. Phonation of the larynges for each treatment was recorded and analyzed for the cepstral peak prominence (CPP), harmonics-to-noise ratio (HNR), and correlation dimension. RESULTS: Kruskal-Wallis rank-sum tests yielded significant differences across shim groups for all parameters. Dunn-Bonferroni post-hoc tests revealed that the control group differed significantly from the 1.5, 2, 2.5, 3, and 3.5 mm groups for all metrics. Moreover, Kendall correlation tests indicated a moderately positive correlation between glottal gap size and correlation dimension, a moderately negative correlation between glottal gap size and CPP and between glottal gap size and the HNR. CONCLUSIONS: Glottic insufficiency provides a source of nonlinearity in phonation. Nonlinear dynamic analysis provides quantitative insight into glottal gap voice. This study encourages future studies to further evaluate the relationship between glottal gap and correlation dimension.

Vocal fold electromyography in patients with endoscopic features of unilateral laryngeal paralysis.

<b><br>Introduction:</b> Electromyography (EMG) of the larynx provides information on the electrophysiological condition of laryngeal muscles and innervation. Integration of information obtained from the EMG exams with the clinical parameters as obtained by other methods for laryngeal assessment (endoscopy, perceptual and acoustic analysis, voice self-assessment) provides a multidimensional picture of dysphonia, which is of particular importance in patients with vocal fold (VF) mobility disorders accompanied by glottic insufficiency.</br> <b><br>Aim:</b> The aim of this study was to evaluate laryngeal EMG records acquired in subjects with unilateral vocal fold immobilization with signs of atrophy and glottic insufficiency.</br> <b><br>Material and methods:</b> From the available material of 74 EMG records of patients referred for the exam due to unilateral laryngeal paralysis, records of 17 patients with endoscopic features suggestive of complete laryngeal muscle denervation were selected. The EMG study of thyroarytenoid muscles of mobile and immobile VFs was evaluated qualitatively and quantitatively at rest and during volitional activity involving free phonation of vowel /e/ [ε].</br> <b><br>Results:</b> In all patients, the EMG records from mobile VFs were significantly different from those from immobile VFs. Despite endoscopic features of paralysis, no VF activity whatsoever was observed in as few as 2 patients so as to meet the neurophysiological definition of paralysis. In 88% of cases, electromyographic activity of the thyroarytenoid muscle was observed despite immobilization and atrophy of the vocal fold. In these patients, neurogenic type of record was observed with numerous high- -amplitude mobility units. On the basis of the results, quantitative features of EMG records indicative of paralysis and residual activity of the thyroarytenoid muscle were determined.</br> <b><br>Conclusions:</b> Qualitative and quantitative analysis of laryngeal EMG records provides detailed information on the condition of vocal fold muscles and innervation. EMG records of mobile vs immobile VFs differ significantly from each other. Endoscopic evaluation does not provide sufficient basis for the diagnosis of complete laryngeal muscle denervation.</br>.

Scoping Review of Surgical Rehabilitation of Post Intubation Phonatory Insufficiency.

OBJECTIVES: Post intubation phonatory insufficiency (PIPI) or posterior glottic diastasis describes posterior glottic insufficiency (PGI) caused by prolonged intubation causing medial arytenoid ulceration, mucosal scarring, and incomplete cricoarytenoid joint adduction. The purpose of this review is to showcase diagnostic findings, surgical rehabilitation, and gaps in our treatment algorithm of PIPI. DATA SOURCES: Embase, PubMed, Scopus, Web of Science. REVIEW METHODS: Two independent reviewers completed a systematic search of the literature studying PIPI. Reported intubation history, laryngeal defect, clinical symptoms, surgical intervention, and outcomes were gathered from included studies. RESULTS: Nine studies met our inclusion criteria for full review, (45 patients) all of which were case reports/series. All patients had posterior glottic defects, most commonly loss of medial arytenoid tissue, causing varying degrees of PGI. Eleven patients had vocal fold (VF) immobility or hypomobility. Treatment interventions were observation (1), speech therapy (2), VF or posterior glottic injection augmentation (15), medialization laryngoplasty (4), arytenoid repositioning (6), endoscopic (19) or open (3) posterior cricoid reduction, local mucosal rotation flap (11), or free mucosal graft (2) to fill the glottic defect. Observation, voice therapy, and augmentation or type 1 laryngoplasty failed to improve symptoms. Other surgical techniques improved symptoms with varying outcomes. CONCLUSION: PIPI is a difficult injury to diagnosis and treat. Conservative measures and augmentation/laryngoplasty often fail to fix the PGI. Our review supports symptom improvement with reconstruction of the posterior glottic defect with cricoid reduction or mucosal grafts. Future investigation is needed to better define the diagnosis and successful treatment algorithm. Laryngoscope, 134:2048-2058, 2024.

Estudio retrospectivo para describir la prevalencia del hiatus glótico longitudinal y su relación con la patología orgánica en pacientes adultos con disfonía

Introducción: El hiatus glótico longitudinal es un signo descrito en la práctica clínica a partir de las fibrolaringoscopias de pacientes con patologías laríngeas. Objetivo: Describir la prevalencia de patologías laríngeas orgánicas y funcionales mediante videolaringoestroboscopia, y evaluar la frecuencia de hiatus longitudinal y su asociación con patología orgánica en pacientes adultos disfónicos. Material y Método: Se realizó un estudio retrospectivo y descriptivo durante 2018-2019 en un hospital de alta complejidad. Se incluyeron las videolaringoestroboscopia de pacientes mayores de 14 años que consultaron por disfonía. Las patologías laríngeas se categorizaron en orgánicas o funcionales. La asociación entre patología orgánica y el hiatus longitudinal se analizó mediante un análisis multivariado ajustado por confundidores. Resultados: Se incluyeron 310 pacientes de los cuales se analizaron 269. La media de edad fue 43,9 ± 7,09 años y el porcentaje de sexo femenino 65,8% (n: 177). La prevalencia de disfonía orgánica fue del 84,01% y de disfonía funcional, del 13,38%. La prevalencia de hiatus longitudinal fue del 23,79% (n: 64). Se observó una asociación, estadísticamente significativa entre la presencia de hiatus longitudinal y la presencia de patología orgánica con OR de12,64 (1,60-99,42; p: 0,01) ajustada por edad, sexo, tabaquismo y antigüedad de la disfonía. Conclusión: La prevalencia de patologías laríngeas orgánicas es mayor a la de funcionales y el hiatus longitudinal se asocia a patología orgánica ajustada por confundidores.

Introduction: Spindle-shaped glottic chink is a sign described in clinical practice from fibrolaryngoscopy of patients with laryngeal pathologies. Aim: to describe the prevalence of organic and functional laryngeal pathologies by videolaringostroboscopy, and to evaluate the frequency of spindle-shaped glottic chink and its association with organic pathology in dysphonic adult patients. Material and Method: A retrospective and descriptive study was conducted during 2018-2019 in a high complexity hospital. Patient's videostroboscopy older than 14 years old who consulted for dysphonia were included. Laryngeal pathologies were categorized into organic or functional diseases. The association between organic pathology and spindle-shaped glottic chink was analyzed using a multivariate analysis adjusted for confounders. Results: 310 patients were included of whom 269 patients were analyzed. The mean age was 43.9 ± 7.09 years and the percentage of female sex was 65.8 % (n: 177). The prevalence of organic dysphonia was 84.01% and of functional dysphonia, 13.38%. The prevalence of spindle-shaped glottic chink was 23.79% (n:64) (18.67-28.91%). A statistically significant association was observed between the presence of spindle-shaped glottic chink and the presence of organic pathology with OR of 12.64 (1.60- 99.42; p: 0.01) adjusted for age, sex, smoking status and history of dysphonia. Conclusion: The prevalence of organic laryngeal pathology is higher than functional and spindle-shaped glottic chink is associated with organic pathology adjusted for confounders.

Vocal Fold Fat injection for Glottic Insufficiency: Systematic Review.

Vocal fold fat injection is a technique for treating glottic insufficiency (GI) resulting from various conditions. The use of fat as a graft has several advantages over other grafts. Similar pliability, and vibratory characteristics as a normal vocal fold, not causing foreign body reactions, having the potential to contain stem cells, and often can be done in the office. Long-term results, however, are unpredictable. The objective of this study is to carry out a systematic review of published articles using the technique of fat injection in the vocal folds. STUDY DESIGN: Systematic review. REVIEW METHODS: A literature search was conducted utilizing the combination of the following keywords "vocal folds fat injection," "laryngoplasty," and "autologous fat injection vocal folds." The criteria inclusion of the study for the systematic review were based on PICOTS (population, intervention, comparison outcome, timing, and setting) and Preferred Reporting Items for Systematic Reviews and Meta-analyses statements. Outcomes reviewed included technique, study duration, perceptual and acoustic analysis, and quality of life preoperation and 1-year postoperation. RESULTS: A systematic review on PubMed, Cochrane, and Embase databases included 13 studies analyzing the data of 472 patients, that had fat injection laryngoplasty for treatment of GI. The causes of GI varied substantially across studies. Considerable heterogeneity across studies was found, including technique for harvest, processing the fat, site of injection, and acoustic analysis. In the studies that measured maximum phonation time (MPT) there was a significant improvement in a follow-up of at least 1 year after the injection. The patient's perception of vocal quality, measured by the Voice Handicap Index, also showed significant improvement in several studies after fat injection laryngoplasty. CONCLUSION: Fat injection laryngoplasty seems to be safe and effective for GI for at least 12 months. Multiple studies show favorable outcomes, but the lack of control groups, the heterogeneity in inclusion criteria, nonstandardized techniques, and objective voice evaluations limit this evaluation.

Is it Always Laryngopharyngeal Reflux? How Voice Disorders Can Manifest as LPR

Introduction: Laryngopharyngeal reflux (LPR) manifests with a constellation of common throat symptoms and inconclusive signs on laryngoscopic exam. It is a diagnosis, often made clinically, that can lead to prescriptions of proton pump inhibitors that are unnecessary and potentially harmful. Glottic insufficiency (GI) and the accompanying hyperfunctional laryngeal behaviors can also present with similar, common throat complaints that may or may not include a qualitative change to the voice. Methods: This is a reflection article. It is written to summarize, explain, and support with evidence the opinion of the author on the topic of how symptoms of voice disorders can easily be mistaken for symptoms of LPR. The offered reflection is based on his experience, research and the available literature. Reflection: This article intends to explore the similarities between GI and LPR, how to ultimately differentiate them and how to approach treatment with a broader differential diagnosis. Conclusion: LPR and GI can present with identical, vague throat, and voice symptoms. Empiric medication trials, behavioral interventions and objective laryngovideostroboscopy, impedance-based reflux, and esophageal motility testing may all be needed, sometimes in a trial and error fashion, to correctly diagnose and treat a patient's symptoms.

Introducción: El reflujo laríngeo-faríngeo (LPR, por sus siglas en inglés) se manifiesta con una serie de síntomas comunes en la garganta y signos no concluyentes en el examen larinoscópico. Es un diagnóstico que a menudo se realiza clínicamente y que puede llevar a la prescripción de inhibidores de la bomba de protones que son innecesarios y potencialmente perjudiciales. La insuficiencia glótica (IG) y los comportamientos laríngeos hiperfuncionales que la acompañan también pueden presentar síntomas de garganta comunes similares, que pueden o no incluir un cambio cualitativo en la voz. Métodos: Este es un artículo de reflexión. Está escrito para resumir, explicar y respaldar con evidencia la opinión del autor sobre cómo los síntomas de los trastornos de la voz pueden confundirse fácilmente con los síntomas del LPR. La reflexión ofrecida se basa en su experiencia, investigación y la literatura disponible. Reflexión: Este artículo tiene la intención de explorar las similitudes entre la IG y el LPR, cómo diferenciarlos finalmente y cómo abordar el tratamiento con un diagnóstico diferencial más amplio. Conclusión: El LPR y la IG pueden presentar síntomas idénticos y vagos en la garganta y la voz. Puede ser necesario realizar ensayos de medicación empírica, intervenciones conductuales y pruebas objetivas de laringovideostroboscopia, reflujo basado en impedancia y motilidad esofágica, a veces de manera experimental, para diagnosticar y tratar correctamente los síntomas de un paciente.

Long-term Outcome of Autologous Lipoinjection Medialization Laryngoplasty versus Type I Thyroplasty.

Glottic insufficiency is incomplete or soft closure of the true vocal folds during phonation and is a common cause of dysphonia. Treatment includes voice therapy, type I thyroplasty, vocal fold injection augmentation (with materials such as autologous fat), arytenoid cartilage repositioning, or a combination of treatment modalities. The present study aimed to compare long-term outcomes of lipoinjection medialization with type I thyroplasty for patients with glottic insufficiency. METHODS: Adult voice center patients who had undergone surgical vocal fold medialization with autologous lipoinjection or with type I thyroplasty for glottic insufficiency were included in this retrospective study. The primary outcome measures were the need for further medialization surgery and improvement in the glottic gap. RESULTS: There were 172 subjects included in this study: 100 subjects underwent type I thyroplasty and 72 subjects underwent autologous lipoinjection medialization. Neither age nor gender differed significantly between thyroplasty and lipoinjection groups. The rate of further medialization surgery did not differ significantly between thyroplasty and lipoinjection groups, but further medialization surgery was performed longer after the initial operation in the thyroplasty group Baseline glottic gap did not differ significantly between thyroplasty and lipoinjection groups. When improvement from baseline was compared between thyroplasty and lipoinjection subjects, the improvement from baseline was similar for both groups at 6 months and at 12 months. Voice handicap index scores improved significantly after thyroplasty or after lipoinjection, and the improvement from baseline was similar in both cohorts. CONCLUSION: Both autologous lipoinjection medialization and type I thyroplasty provide effective medialization for patients with glottic insufficiency. Both techniques yield similar reoperation rates, and the benefit of surgery appears to last for at least 1 year for most patients.

Long-term outcomes of bilateral medialisation thyroplasty in patients with vocal fold atrophy with or without sulcus.

OBJECTIVE: Evaluate long-term voice outcome after bilateral medialisation thyroplasty in glottic insufficiency due to vocal fold atrophy with or without sulcus. METHODS: Patients after medialisation thyroplasty for vocal fold atrophy with or without sulcus were identified. Long-term post-operative subjective voice outcomes (> 1 year) using Voice Handicap Index-30, subjective ratings on voice aspects and study-specific questionnaire were compared to pre-operative and shorter-term (1 year) values. RESULTS: Thirty-six patients were identified, of which 26 were included (16 atrophy, 10 sulcus) with median follow up of 6.7 years. Mean Voice Handicap Index score at > 1 year (40.0) showed clinically relevant (≥ 15 for groups) and statistically significant improvement compared to pre-operative score (58.1) and remained stable compared to post-operative score (35.7) at one year. Ten patients (56 per cent) reported clinically relevant improvement (≥ 10) after more than five years. CONCLUSION: Long-term improvement in subjective voice outcomes is attainable in a significant proportion of patients undergoing bilateral medialisation thyroplasty for atrophy with or without sulcus.

Use of a Novel Hypercrosslinked Carbohydrate Scaffold for Vocal Fold Medialization in an Ovine Model.

Objectives: Vocal fold medialization is commonly performed for glottic insufficiency and vocal fold immobility. Currently available materials are temporary injectables or synthetic implants. Acellular scaffolds may allow vocal fold augmentation with autologous tissue via host cell migration. The purpose of this investigation was to evaluate the use of a novel carbohydrate scaffold as a medialization implant. Study Design: Animal model. Setting: Academic medical center. Methods: Unilateral type I medialization thyroplasty was performed in 3 Dorper cross ewes using a hypercrosslinked carbohydrate polymer (HCCP) scaffold. Animals were monitored for 4 weeks for general well-being, dyspnea, and weight loss. The animals were euthanized at 4 weeks and the larynges harvested. Histologic evaluation was performed to assess for adverse tissue reaction, migration, degradation, and biocompatibility. Results: No adverse events were reported. No animals lost weight or displayed evidence of dyspnea. Histology demonstrated ingrowth of host cells and neovascularization with minimal peri-implant inflammatory reaction. Cellular ingrowth into the scaffold was predominately made up of fibroblasts and early inflammatory cells. Scaffold shape was grossly maintained as it underwent degradation and replacement with host tissue. Migration of the implant material was not observed. Conclusion: Vocal fold medialization in an ovine model with an HCCP scaffold resulted in the ingrowth of host cells with minimal peri-implant inflammation. Scaffold shape was maintained without evidence of migration as it underwent replacement with host tissue. Further research is required to assess long-term efficacy in comparison to currently available implants.

Evaluation and Management of Inflammatory Reactions to Vocal Fold Injection Laryngoplasty with Hyaluronic Acid.

OBJECTIVES: Inflammatory reaction to vocal fold injection laryngoplasty with hyaluronic acid (HA) is a rare condition whose optimal management is not established. In this study, we aim to review the presentation of these reactions and outline an approach for evaluation and management. METHODS: We performed a retrospective review of all patients at our institution who underwent vocal fold injection augmentation with HA during the period extending from August 2018 until October 2022. We then identified patients with postinjection inflammatory reaction and reviewed demographic data, indication for injection, amount of HA injected, setting of procedure, and symptoms. The types of complication, management plan, onset, and time to complete resolution were also recorded. A comprehensive literature search for similar complications was conducted for comparative analysis. Once the available data were aggregated with our institutional experience, we developed an algorithmic approach to manage this condition. RESULTS: We identified 83 patients (124 vocal folds) who underwent vocal fold injection laryngoplasty with HA over a 4-year period. Four patients (4.8%) had a postprocedure inflammatory reaction (5.6% of all vocal folds). Of the four patients, three presented with dyspnea and stridor, while one presented with dysphonia, with onset of symptoms ranging from 24 to 48 hour postinjection. All patients were treated with corticosteroids. For comparative analysis, we identified 24 patients from the literature with reported inflammatory reactions to HA. CONCLUSION: We suggest an algorithmic approach to managing laryngeal inflammation following HA injection. Familiarity with treatment for this rare complication is essential to avoid significant morbidity and achieve optimal outcomes.

An Exploration of the Risk Factors, Severity, and Sequelae of Vocal Fold Hemorrhage in a Population of Voice Patients Before and After Diagnosis.

BACKGROUND: Vocal fold hemorrhage (VFH) is the rupture (usually acute) of a blood vessel within the true vocal fold. The long-term sequelae of VFH on the mucosal wave (MW) and glottic gap on video stroboscopy remain understudied. The primary objective of this study was to investigate the short-term and long-term consequences of VFH through measured and rated analysis of the mucosal wave and glottic gap. METHODS: The presence of VFH and its extent (limited/moderate vs. extensive VFH) were identified. The primary outcome of this study was mucosal wave, which was assessed on an ordinal scale by three blinded raters pre and posthemorrhage. Only patients who had undergone strobovideolaryngoscopy before sustaining VFH were included. Mucosal wave and glottic gap also were measured using image pixel analysis using the open-access tool, ImageJ (NIH, Bethesda, MD). RESULTS: Twenty-three subjects were included in this study (mean age 39.78 ± 15.54). Intra-rater reliability for MW ratings was 81.48% ± 6.150% (minimum 77.78%) for all evaluators (κ = 0.519 [0.267-0.772], P < 0.001). Inter-rater reliability analysis revealed 75.56% agreement between evaluators (κ = 0.524 [0.425-0.623], P < 0.001). MWMeasured extrapolated from ImageJ methodology correlated significantly with MWRated (n = 70, r = 0.448, P < 0.001). ΔMWMeasured from baseline to follow-up evaluation were compared for both the initial follow-up visit (FU1) and the second follow-up visit (FU2) [-4.135 ± 31.01 vs. 36.50 ± 39.97, P = 0.025]. Hence, ΔMWMeasured was significantly better by FU2 than FU1, with the larger positive change from baseline representing a greater improvement in the measured mucosal wave. Additionally, there were significant differences in ΔMWRated between those with limited/moderate VFH and those with extensive VFH at FU1. Duration of absolute voice rest correlated significantly with time to VFH resolution. Long-term change in mucosal wave after hemorrhage was assessed using both ΔMWMeasured and MWRated. Based on ΔMWRater, 35.0% of subjects demonstrated ongoing and worse mucosal wave restriction compared to baseline at their most recent follow-up visit. Based on ΔMWMeasured, 50.0% of the subjects showed ongoing and worse mucosal wave restriction compared to baseline at their most recent follow-up visit. CONCLUSION: Overall long-term restrictions in MW after hemorrhage were present in 35.0% of the subjects based on ratings and 50.0% of the patients based on the measured MW using ImageJ, demonstrating the importance of ongoing study into this pathology and how to prevent it, especially in PVU and professional singers. Patients presenting with extensive hemorrhage were at risk for more prominent, detectable changes in mucosal wave compared to those with limited/moderate hemorrhage in the short-term, defined by a mean FU time of 3 months, but not long-term, characterized by a mean FU time 6 months or greater. Whether the severity of VFH is a true indicator of mucosal wave alterations requires additional study, as does the reliability and validity of ImageJ mucosal wave and glottic gap measurement techniques.

A Simple and Reproducible In Vivo Rabbit Phonation Model for Glottic Insufficiency.

OBJECTIVE: The objective of this study is to describe an in vivo rabbit phonation model for glottic insufficiency that is simple and reproducible by means of unilateral transcricothyroid laryngeal muscle stimulation and high-speed video recordings of evoked phonation. STUDY DESIGN: Nonrandomized controlled animal trial. SETTING: Academic medical center. METHODS: A single operation including evoked phonation with bilateral and unilateral transcricothyroid laryngeal muscle stimulation conditions was modeled using 6 New Zealand white rabbits. The effect of stimulation method on glottic cycle, pitch, and loudness was compared. Endoscopic recordings using 5000 frames-per-second image capture technology and audiologic recordings were obtained for all phonation conditions. Primary outcome measures included means of maximum glottal area (MGA)/length pixel ratio, right and left amplitude/length pixel ratios, calculated cycle frequency, auditory recorded frequency, and maximum auditory intensity. Measurements were obtained via pixel counts using ImageJ. RESULTS: Mean MGA/length was significantly greater with unilateral, 20.30, vs bilateral, 9.62, stimulation (P = .043). Mean frequency of 479.92 Hz vs 683.46 Hz (P = .027) and mean maximum intensity of 76.3 dB vs 83.5 dB (P = .013) were significantly increased from unilateral to bilateral stimulation. There was no significant difference in mean right amplitude/length between unilateral and bilateral. CONCLUSION: The described model demonstrates a simple and reproducible means of producing glottic insufficiency due to unilateral vocal fold bowing and represents a pathway for better understanding the biomechanics and pathophysiology of glottic insufficiency due to superior laryngeal nerve injury and vocal fold immobility and offers the potential to compare treatment modalities through in vivo study.

Changes in Cough Airflow and Acoustics After Injection Laryngoplasty.

OBJECTIVE/HYPOTHESIS: We explored the following hypotheses in a cohort of patients undergoing injection laryngoplasty: (1) glottic insufficiency affects voluntary cough airflow dynamics and restoring glottic competence may improve parameters of cough strength, (2) cough strength can be inferred from cough acoustic signal, and (3) glottic competence changes cough sounds and correlates with spectrogram morphology. STUDY TYPE/DESIGN: Prospective interventional study. METHODS: Subjects with glottic insufficiency secondary to unilateral vocal fold paresis, paralysis, or atrophy, and scheduled for injection laryngoplasty completed an instrumental assessment of voluntary cough airflow using a pneumotachometer and a protocolized voluntary cough sound recording. A Wilcoxon signed-rank test was used to compare the differences between pre- and post-injection laryngoplasty in airflow and acoustic measures. A Spearman rank-order correlation was used to evaluate the association between airflow and acoustic cough measures. RESULTS: Twenty-five patients (13F:12M, mean age 68.8) completed voluntary cough airflow measurements and 22 completed cough sound recordings. Following injection laryngoplasty, patients had a statistically significant decreased peak expiratory flow rise time (PEFRT) (mean change: -0.03 s, SD: 0.06, p = 0.04) and increased cough volume acceleration (mean change: 13.1 L/s2 , SD: 33.9, p = 0.03), suggesting improved cough effectiveness. Correlation of cough acoustic measures with airflow measures showed a weak relationship between PEFRT and acoustic energy (coefficient: -0.31, p = 0.04) and peak power density (coefficient: -0.35, p = 0.02). CONCLUSIONS: Our study thus indicates that injection laryngoplasty may help avert aspiration in patients with glottic insufficiency by improving cough effectiveness and that improved cough airflow measures may be tracked with cough sounds. LEVEL OF EVIDENCE: 3 Laryngoscope, 133:S1-S14, 2023.

A self-fused hydrogel for the treatment of glottic insufficiency through outstanding durability, extracellular matrix-inducing bioactivity and function preservation.

Injection laryngoplasty with biomaterials is an effective technique to treat glottic insufficiency. However, the inadequate durability, deficient pro-secretion of extracellular matrix (ECM) and poor functional preservation of current biomaterials have yielded an unsatisfactory therapeutic effect. Herein, a self-fusing bioactive hydrogel comprising modified carboxymethyl chitosan and sodium alginate is developed through a dual-crosslinking mechanism (photo-triggered and dynamic covalent bonds). Owing to its characteristic networks, the synergistic effect of the hydrogel for vocal folds (VFs) vibration and phonation is adequately demonstrated. Notably, owing to its inherent bioactivity of polysaccharides, the hydrogel could significantly enhance the secretion of major components (type I/III collagen and elastin) in the lamina propria of the VFs both in vivo and in vitro. In a rabbit model for glottic insufficiency, the optimized hydrogel (C1A1) has demonstrated a durability far superior to that of the commercially made hyaluronic acid (HA) Gel. More importantly, owing to the ECM-inducing bioactivity, the physiological functions of the VFs treated with the C1A1 hydrogel also outperformed that of the HA Gel, and were similar to those of the normal VFs. Taken together, through a simple-yet-effective strategy, the novel hydrogel has demonstrated outstanding durability, ECM-inducing bioactivity and physiological function preservation, therefore has an appealing clinical value for treating glottic insufficiency.

The Additive Effectiveness of Inspiratory Muscle Training on Glottic Closure and Subjective Voice Outcomes of Patients With Benign Lesion After Hyaluronic Acid Laryngoplasty.

OBJECTIVES: For patients with glottic insufficiency disease, injection laryngoplasty is a rapid and efficient management option that complements voice therapy. Some studies have indicated that respiratory muscle training may also show promise in patients with voice disorders. However, the effect of respiratory muscle training in patients with glottic insufficiency was reported to be limited, and whether it provides additional benefit after standard management requires further evaluation. We aimed to investigate the effectiveness of inspiratory muscle training on glottis closure and patient-reported voice quality in glottic insufficiency patients who had been treated with hyaluronic acid injection. STUDY DESIGN: Retrospective observational study. METHODS: We included 46 patients with glottic insufficiency who had undergone hyaluronic acid injection. Twenty of them had undergone inspiratory muscle training during three months. We measured patients' changes in glottic status according to the normalized glottal gap area and bowing index, as well as voice quality of life according to the voice handicap index 10 and the voice outcome survey, before and after training. RESULTS: Patients who underwent inspiratory muscle training had higher odds of experiencing better improvement in all scores. The range of odds ratios ranged from 2.5 to 6.3 for changes in scores, and from 3.8 to 22.2 for changes in score percentages. Of note, the effect of training on percentage changes in the normalized glottal gap area score was significant (P= 0.0127) after adjustment for the duration of vocal disease, body mass index and BMI, and history of gastroesophageal reflux disease. CONCLUSIONS: Inspiratory muscle training can improve the glottal gap after injection laryngoplasty, and may be applied in clinical practice.

Tissue Engineering as a Promising Treatment for Glottic Insufficiency: A Review on Biomolecules and Cell-Laden Hydrogel.

Glottic insufficiency is widespread in the elderly population and occurs as a result of secondary damage or systemic disease. Tissue engineering is a viable treatment for glottic insufficiency since it aims to restore damaged nerve tissue and revitalize aging muscle. After injection into the biological system, injectable biomaterial delivers cost- and time-effectiveness while acting as a protective shield for cells and biomolecules. This article focuses on injectable biomaterials that transport cells and biomolecules in regenerated tissue, particularly adipose, muscle, and nerve tissue. We propose Wharton's Jelly mesenchymal stem cells (WJMSCs), induced pluripotent stem cells (IP-SCs), basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), insulin growth factor-1 (IGF-1) and extracellular vesicle (EV) as potential cells and macromolecules to be included into biomaterials, with some particular testing to support them as a promising translational medicine for vocal fold regeneration.

Severe Airway Edema Following Calcium Hydroxylapatite (CaHA) Injection Augmentation.

This case study presents an abnormal complication after routine injection augmentation using calcium hydroxylapatite (CaHA) vocal fold filler in-office on a 73-year-old female. The patient presented initially with severe dysphonia, hypophonia, and a past surgical history of total thyroidectomy, bilateral neck dissection, and a right lateral neck dissection for history of metastatic papillary thyroid carcinoma. She also had a past medical history of hypothyroidism. Post-injection of CaHA, the patient developed severe laryngeal edema, limited vocal cord mobility, obliteration of the pyriform, and a significantly reduced airway aperture requiring intensive care monitoring. Although uncommon, injectable fillers can result in complications which can be severe. Careful technique, the volume of injectate, and hypersensitivity should be considered in reducing complications following injection augmentation. There are multiple injection techniques to consider. The most direct approach is with direct laryngoscopy to allow for visualization of glottic incompetence. A smaller slotted laryngoscope can be considered for vocal fold injection as an alternative and without endotracheal intubation. Although these techniques allow for injection, real-time assessment of vocal fold closure is done in an awake patient. Therefore, laryngeal injection can be considered via percutaneous, per-oral, and trans-nasal approaches.

Glottic Insufficiency in the Vertical Plane in Patients With Unknown-Source Unilateral Vocal Fold Hypomobility.

OBJECTIVE: To observe the laryngeal CT and strobe laryngoscopy signs of unilateral vocal fold hypomobility (UVFHM) in patients with well-closed glottises in the horizontal plane. METHODS: A retrospective analysis was performed on 18 subjects with well-closed glottises in the horizontal plane using strobe laryngoscopy, 9 patients diagnosed with unilateral vocal fold hypomobility with an unknown etiology were enrolled in the UVFHM group, and 9 healthy matched subjects with symmetrical bilateral vocal fold movement were enrolled in the control group. Vertical plane distances of bilateral vocal folds and three-dimensional structural parameters of vocal folds were measured through laryngeal CT. Glottic insufficiency in the vertical plane and reflux findings scores (RFS) were assessed under laryngeal CT and strobe laryngoscopy. Reflux symptom index (RSI) were collected. SPSS25.0 software was used for statistical analysis. RESULTS: The height differences in vertical plane and thicknesses of bilateral vocal folds in the UVFHM group were larger than those in the control (P < 0.05), while the length, width and subglottic convergence angle of the vocal folds were not statistically significant between the two groups (P > 0.05). In the UVFHM group, laryngeal CT showed that 77.78% of patients (7/9) had glottic insufficiency in the vertical plane, with height differences ranging from 0.3 to 1.9 mm and a mean of 0.76mm. However, strobe laryngoscopy showed that 33.33% (3/9) had glottic insufficiency in the vertical plane. The proportion of patients with glottic insufficiency in vertical plane in the UVFHM group was significantly higher than that in the control group (P < 0.05). RSI and RFS scores of the UVFHM group were higher than those of the control group (P < 0.05). CONCLUSION: Glottic insufficiency in the vertical plane often occurred in patients with UVFHM with an unknown cause of hoarseness, so the presence of glottic insufficiency in the vertical plane should be considered when hoarseness is detected by clinicians. Laryngeal dynamic CT can enhance the diagnostic rate compared to strobe laryngoscopy. Unexplained UVFHM patients have higher RSI and RFS compared to control subjects, warranting further research about the relationship between UVFHM and laryngopharyngeal reflux.

Postintubation Phonatory Insufficiency: A Challenging Diagnosis.

INTRODUCTION: Glottic insufficiency is an important cause of dysphonia and can be frequently overlooked in the clinical evaluation. The differential diagnoses of this entity are diverse and include postintubation phonatory insufficiency (PIPI). These patients present with glottic insufficiency symptoms, associated with normal laryngeal imaging evaluation with no evident lesions. There is scarce literature describing this entity, since it is usually underdiagnosed. OBJECTIVES: The aim of this study is to describe two clinical cases diagnosed with PIPI at our center's Voice Unit, discuss their clinical features, diagnostic evaluation, and treatment alternatives. CASE SUMMARY: We report two clinical cases of prolonged orotracheal intubation (OTI) that developed dysphonia, vocal fatigue, a breathy voice, and poor vocal projection after being discharged from the hospital. Laryngoscopic evaluation showed no lesions in the membranous glottis and normal vocal fold mobility. Respiratory glottis was difficult to evaluate because of redundant arytenoids. To improve visualization, a laryngotracheoscopy with transtracheal anesthesia was performed in-office, exposing scar tissue medial to the vocal processes and respiratory vocal fold, confirming PIPI. DISCUSSION: Prolonged OTI can damage the medial arytenoid mucosa producing a posterior glottic gap that determines symptoms of glottic insufficiency. Multiple treatment options have been described yet few achieve a sufficient closure of the defect, so management is initially based on counseling and speech therapy. CONCLUSIONS: PIPI is usually difficult to diagnose and should be sought directly in the clinical evaluation, especially if there are no obvious lesions in the membranous glottis.