Search Results (31)

Introduction: The vascular architecture of the vocal folds plays a critical role in sustaining the dynamic demands of phonation. Disruptions in this microvascular system are linked to various pathological conditions, including Reinke’s edema, hemorrhage, and laryngeal carcinoma. This review explores the structural and functional components of vocal fold microvascularization, with emphasis on pericytes, endothelial interactions, and neurovascular regulation. Materials and Methods: A systematic review of the literature was conducted using databases such as PubMed, Scopus, Web of Science, and Embase. Keywords included “pericytes”, “Reinke’s edema”, and “vocal fold microvascularization”. Selected studies were peer-reviewed and met criteria for methodological quality and relevance to laryngeal microvascular physiology and pathology. Results: The vocal fold vasculature is organized in a parallel, tree-like pattern with distinct arterioles, capillaries, and venules. Capillaries dominate the superficial lamina propria, while transitional vessels connect to deeper arterioles surrounded by smooth muscle. Pericytes, present from birth, form tight associations with endothelial cells and contribute to capillary stability, vessel remodeling, and mechanical protection during vibration. Their thick cytoplasmic processes suggest a unique adaptation to the biomechanical stress of phonation. Arteriovenous anastomoses regulate perfusion by shunting blood according to functional demand. Furthermore, neurovascular control is mediated by noradrenergic fibers and neuropeptides such as VIP and CGRP, modulating vascular tone and glandular secretion. The limited lymphatic presence in the vocal fold mucosa contributes to edema accumulation while also restricting carcinoma spread, offering both therapeutic challenges and advantages. Conclusions: A deeper understanding of vocal fold microvascularization enhances clinical approaches to voice disorders and laryngeal disease, offering new perspectives for targeted therapies and regenerative strategies. Full article

Introduction: Airway management remains a high-risk intervention in a subset of patients, with traditional predictors like the Mallampati score demonstrating poor sensitivity and specificity. Point-of-care ultrasound (POCUS) has emerged as a transformative tool, offering real-time, objective assessment of airway anatomy to improve safety and outcomes. Methods: A narrative approach was conducted to evaluate the literature on airway ultrasound, incorporating clinical metrics and procedural applications. Results: Ultrasound has demonstrated utility in pre-intubation risk stratification using quantitative measures such as skin-to-epiglottis distance (>2.75 cm) and hyomental distance ratio (<1.2), which outperform traditional exams, especially in obese patients. Procedural uses include endotracheal tube confirmation with 98.9% sensitivity and enhanced success rates in emergent cricothyroidotomy—from 50% to nearly 100%—in patients with difficult anatomy. Dynamic applications like assessing laryngeal edema via parapharyngeal thickness offer advantages over traditional cuff leak tests. Technical considerations such as optimal probe selection, patient positioning, and interpretation of key anatomical landmarks are also discussed. Conclusions: Airway ultrasound is poised to become a standard tool in perioperative and critical care settings. The review concludes by emphasizing POCUS as an indispensable adjunct for modern airway management. Full article

Unilateral vocal fold paralysis (UVFP) can lead to significant dysphonia. Medialization thyroplasty type 1 (TT1) is a common surgical intervention aiming at improving vocal quality by optimally positioning the paralyzed fold to generate the necessary vibrations for phonation. Implants are generally placed through the thyroid cartilage in a sedated patient and positioned either underneath the level of the vocal folds (infraglottal medialization or IM) or at the level of the vocal folds (glottal medialization or GM). Using high-speed three-dimensional digital image correlation (3D-DIC) in an ex vivo canine hemilarynx model, this study explores the impact of implant location, specifically IM versus GM on the pre-phonatory and dynamic vertical thickness, glottal divergence, flow rate (Q), and cepstral peak prominence (CPP) under varying adduction and subglottal pressure conditions. IM consistently increased glottal divergence and dynamic vertical thickness, particularly in under-adducted states (AL1), despite producing lower static thickness than GM. CPP remained unaffected by the implant condition, but Q decreased significantly with IM under AL1, indicating enhanced glottal resistance and closure. These findings suggest that IM may offer superior functional outcomes by restoring divergent glottal shaping and improving vibratory efficiency. This study also introduces a validated method for dynamically quantifying vocal fold thickness and emphasizes the importance of implant depth in medialization thyroplasty strategies. Full article

Objectives: This study evaluates the potential of high-speed videoendoscopy (HSV) in differentiating between benign and malignant glottic lesions, offering a non-invasive diagnostic tool for clinicians. Moreover, a new parameter derived from high-speed videoendoscopy (HSV) had been proposed and implemented in the analysis for an objective assessment of the vocal fold stiffness. Methods: High-speed videoendoscopy (HSV) was conducted on 102 participants, including 21 normophonic individuals, 39 patients with benign vocal fold lesions, and 42 with glottic cancer. Laryngotopographic parameter describing the stiffness of vocal fold (SAI) and kymographic parameters describing amplitude, symmetry, and glottal dynamics were quantified. Statistical differences between groups were assessed using receiver operating characteristic (ROC) analysis and lesion classification was performed using a machine learning model. Results: Univariate receiver operating characteristic (ROC) analysis revealed that SAI (AUC = 0.91, 95% CI: 0.839–0.962) and weighted amplitude asymmetry (AUC = 0.92, 95% CI: 0.85–0.974) were highly effective in distinguishing between normophonic and organic lesions (p < 0.01). Further multivariate analysis using machine learning models demonstrated improved accuracy, with the SVM classifier achieving an AUC of 0.93 for detecting organic lesions and 0.83 for distinguishing benign from malignant lesions. Conclusions: The study demonstrates the potential value of parameter describing the pliability of infiltrated vocal fold (SAI) as a non-invasive tool to support histopathological evaluation in laryngeal lesions, with machine learning models enhancing diagnostic performance. Full article

Advancements in dynamic laryngeal imaging, particularly high-speed videoendoscopy (HSV), have addressed several limitations of laryngovideostroboscopy (LVS). This study aimed to compare the success rates of LVS and HSV in generating recordings suitable for objective functional assessment of vocal fold movements. Methods: This study included 200 patients with voice disorders (123 with benign glottal lesions, 56 with malignant lesions, and 21 with functional voice disorders) and 47 normophonic individuals. All participants underwent LVS followed by HSV. Kymographic analysis was performed to evaluate phonatory parameters, including amplitude, symmetry, and glottal dynamics. The success of both methods in generating analyzable kymograms was assessed, and statistical comparisons were made using the chi-square test (significance level set at p < 0.05). Results: The failure rate for LVS was significantly higher (43.32%) compared to HSV. HSV successfully generated kymograms in 68.22% of cases where LVS failed. The primary factors contributing to LVS failure included synchronization issues, inadequate recording brightness, unstable phonation, and hidden glottal opening. Failure rates related to structural obstacles were similar between the two methods. HSV demonstrated superior kymogram feasibility across all subgroups, with the highest success observed in cases of organic glottal pathologies (30.73%). A significant advantage of HSV was observed for both benign and malignant glottal lesions, especially in cases of asynchronous vocal fold oscillations. Conclusions. By overcoming the inherent limitations of LVS, HSV provides a more reliable and objective assessment of phonatory function. Its ability to generate suitable kymograms with greater precision makes HSV a valuable tool for routine clinical diagnostics, enabling the accurate identification of subtle laryngeal pathologies and enhancing diagnostic accuracy. Full article

The present paper investigates the link between perception and production in the laryngeal phonology of multilingual speakers, focusing on non-contrastive segments and the dynamic aspect of these processes. Fourteen L1 Hungarian, L2 English, and L3 Spanish advanced learners took part in the experiments. The production experiments examined the aspiration of voiceless stops in word-initial position, regressive voicing assimilation, and pre-sonorant voicing; the latter two processes were analyzed both word-internally and across word boundaries. The perception experiments aimed to find out whether learners notice the phonetic outputs of these processes and regard them as linguistically relevant. Our results showed that perception and production are not aligned. Accurate production is dependent on accurate perception, but accurate perception is not necessarily transferred into production. In laryngeal postlexical processes, the native language seems to play the primary role even for highly competent learners, but markedness might be relevant too. The novel findings of this study are that phonetic category formation seems to be easier than the acquisition of dynamic allophonic alternations and that metaphonological awareness is correlated with perception but not with production. Full article

This study investigates the impact of subglottic stenosis (SGS) on voice production using a subject-specific laryngeal and airway model. Direct numerical simulations of fluid–structure–acoustic interaction were employed to analyze glottal flow dynamics, vocal fold vibration, and acoustics under realistic conditions. The model accurately captured key physiological parameters, including the glottal flow rate, vocal fold vibration patterns, and the first four formant frequencies. Simulations of varying SGS severity revealed that up to 75% stenosis, vocal function remains largely unaffected. However, at 90% severity, significant changes in glottal flow and acoustics were observed, with vocal fold vibration remaining stable. At 96%, severe reductions in glottal flow and acoustics, along with marked changes in vocal fold dynamics, were detected. Flow resistance, the ratio of glottal to stenosis area, and pressure drop across the vocal folds were identified as critical factors influencing these changes. The use of anatomically realistic airway and vocal fold geometries revealed that while anatomical variations minimally affect voice production at lower stenosis grades, they become critical at severe stenosis levels (>90%), particularly in capturing distinct anterior–posterior opening patterns and focused jet effects that alter glottal dynamics. These findings suggest that while simplified models suffice for analyzing mild to moderate stenosis, patient-specific geometric details are essential for accurate prediction of vocal fold dynamics in severe cases. Full article

Emotional communication is a multi-modal phenomenon involving posture, gestures, facial expressions, and the human voice. Affective states systematically modulate the acoustic signals produced during speech production through the laryngeal muscles via the central nervous system, transforming the acoustic signal into a means of affective transmission. Additionally, a substantial body of research in sonobiology has shown that audible acoustic waves (AAW) can affect cellular dynamics. This pilot study explores whether the physical–acoustic changes induced by gratitude states in human speech could influence cell proliferation and Ki67 expression in non-auditory cells (661W cell line). We conduct a series of assays, including affective electroencephalogram (EEG) measurements, an affective text quantification algorithm, and a passive vibro-acoustic treatment (PVT), to control the CO₂ incubator environment acoustically, and a proliferation assay with immunolabeling to quantify cell dynamics. Although a larger sample size is needed, the hypothesis that emotions can act as biophysical agents remains a plausible possibility, and feasible physical and biological pathways are discussed. In summary, studying the impact of gratitude AAW on cell biology represents an unexplored research area with the potential to enhance our understanding of the interaction between human cognition and biology through physics principles. Full article

The primary acoustic signal of the voice is generated by the complex oscillation of the vocal folds (VFs), whereby physicians can barely examine the medial VF surface due to its anatomical inaccessibility. In this study, we investigated possibilities to infer medial surface dynamics by analyzing correlations in the oscillatory behavior of the superior and medial VF surfaces of four human hemilarynges, each in 24 different combinations of flow rate, VF adduction, and elongation. The two surfaces were recorded synchronously during sustained phonation using two high-speed camera setups and were subsequently 3D-reconstructed. The 3D surface parameters of mean and maximum velocities and displacements and general phonation parameters were calculated. The VF oscillations were also analyzed using empirical eigenfunctions (EEFs) and mucosal wave propagation, calculated from medial surface trajectories. Strong linear correlations were found between the 3D parameters of the superior and medial VF surfaces, ranging from 0.8 to 0.95. The linear regressions showed similar values for the maximum velocities at all hemilarynges (0.69–0.9), indicating the most promising parameter for predicting the medial surface. Since excessive VF velocities are suspected to cause phono-trauma and VF polyps, this parameter could provide added value to laryngeal diagnostics in the future. Full article

Cancer disclosure represents a complex healthcare dynamic. Physicians or caregivers may be prompted to withhold diagnosis information from patients. This study aims to comprehensively map and synthesize available evidence about diagnosis nondisclosure regarding head and neck cancer (HNC) patients. Following the Joanna Briggs Institute guidelines, a scoping review was conducted across major databases without period restriction, yielding 9238 publications. After screening and selection, a descriptive synthesis was conducted. Sixteen studies were included, primarily conducted in academic settings (75%) from Europe and Asia, with a total population of 662 patients predominantly diagnosed with brain, oral, pharyngeal, or laryngeal tumors. Remarkably, 22.51% of patients were unaware of their diagnosis. Although physicians were the main source of diagnostic information (35%), they reported to often use vague terms to convey malignancy. Additionally, 13.29% of patients were aware of their diagnosis from sources other than doctors or caregivers. Caregivers (55%) supported diagnosis concealment, and physicians tended to respect family wishes. A high diagnosis-to-death interval, education, and age significantly influenced diagnosis disclosure. HNC patients expressed a desire for personalized open communication. Multiple factors influenced the decision on diagnosis disclosure. Current evidence on this topic varies significantly, and there is limited research on the consequences of nondisclosure. These findings reflect the underestimation of the patients’ outlook in the diagnosis process and highlight the need for further research, aiming to establish open communication and patient autonomy during the oncological journey. Full article

Changes in pharyngeal and upper-esophageal-sphincter (UES) motor dynamics contribute to swallowing dysfunction. Children with type 1 laryngeal clefts can present with swallowing dysfunction and associated symptoms which may persist even after the initial endoscopic intervention. This study sought to characterize pharyngeal and esophageal motor function in children with type 1 laryngeal clefts who had persistent presenting symptoms after their initial therapeutic intervention. We retrospectively analyzed high-resolution esophageal manometry studies of children ≤ 18 years old with type 1 laryngeal clefts who had an esophageal manometry study performed for persistent symptoms after an initial repair. A total of 16 children were found to have significantly increased UES resting pressure, UES pre- and post-swallow maximum pressures, and duration of UES contraction during swallows in comparison to nine age-matched controls of children without pharyngeal anatomical abnormalities. There was no difference between UES residual pressures or pharyngeal dynamics between the two groups. UES resting and residual pressures did not correlate with VFFS in penetration and aspiration scores of children with type 1 laryngeal clefts status post repair. Our study is the first to identify specific changes in UES motor function in patients with type 1 laryngeal cleft post initial repair. Full article

Synthetic silicone larynx models are essential for understanding the biomechanics of physiological and pathological vocal fold vibrations. The aim of this study is to investigate the effects of artificial ligament fibers on vocal fold vibrations in a synthetic larynx model, which is capable of replicating physiological laryngeal functions such as elongation, abduction, and adduction. A multi-layer silicone model with different mechanical properties for the musculus vocalis and the lamina propria consisting of ligament and mucosa was used. Ligament fibers of various diameters and break resistances were cast into the vocal folds and tested at different tension levels. An electromechanical setup was developed to mimic laryngeal physiology. The measurements included high-speed video recordings of vocal fold vibrations, subglottal pressure and acoustic. For the evaluation of the vibration characteristics, all measured values were evaluated and compared with parameters from ex and in vivo studies. The fundamental frequency of the synthetic larynx model was found to be approximately 200–520 Hz depending on integrated fiber types and tension levels. This range of the fundamental frequency corresponds to the reproduction of a female normal and singing voice range. The investigated voice parameters from vocal fold vibration, acoustics, and subglottal pressure were within normal value ranges from ex and in vivo studies. The integration of ligament fibers leads to an increase in the fundamental frequency with increasing airflow, while the tensioning of the ligament fibers remains constant. In addition, a tension increase in the fibers also generates a rise in the fundamental frequency delivering the physiological expectation of the dynamic behavior of vocal folds. Full article

Airway management is a common and critical procedure in acute settings, such as the Emergency Department (ED) or Intensive Care Unit (ICU) of hospitals. Many of the traditional physical examination methods have limitations in airway assessment. Point-of-care ultrasound (POCUS) has emerged as a promising tool for airway management due to its familiarity, accessibility, safety, and non-invasive nature. It can assist physicians in identifying relevant anatomy of the upper airway with objective measurements of airway parameters, and it can guide airway interventions with dynamic real-time images. To date, ultrasound has been considered highly accurate for assessment of the difficult airway, confirmation of proper endotracheal intubation, prediction of post-extubation laryngeal edema, and preparation for cricothyrotomy by identifying the cricothyroid membrane. This review aims to provide a comprehensive overview of the key evidence on the use of ultrasound in airway management. Databases including PubMed and Embase were systematically searched. A search strategy using a combination of the term “ultrasound” combined with several search terms, i.e., “probe”, “anatomy”, “difficult airway”, “endotracheal intubation”, “laryngeal edema”, and “cricothyrotomy” was performed. In conclusion, POCUS is a valuable tool with multiple applications ranging from pre- and post-intubation management. Clinicians should consider using POCUS in conjunction with traditional exam techniques to manage the airway more efficiently in the acute setting. Full article

The extrathoracic oral airway is not only a major mechanical barrier for pharmaceutical aerosols to reach the lung but also a major source of variability in lung deposition. Using computational fluid dynamics, deposition of 1–30 µm particles was predicted in 11 CT-based models of the oral airways of adults. Simulations were performed for mouth breathing during both inspiration and expiration at two steady-state flow rates representative of resting/nebulizer use (18 L/min) and of dry powder inhaler (DPI) use (45 L/min). Consistent with previous in vitro studies, there was a large intersubject variability in oral deposition. For an optimal size distribution of 1–5 µm for pharmaceutical aerosols, our data suggest that >75% of the inhaled aerosol is delivered to the intrathoracic lungs in most subjects when using a nebulizer but only in about half the subjects when using a DPI. There was no significant difference in oral deposition efficiency between inspiration and expiration, unlike subregional deposition, which shows significantly different patterns between the two breathing phases. These results highlight the need for incorporating a morphological variation of the upper airway in predictive models of aerosol deposition for accurate predictions of particle dosimetry in the intrathoracic region of the lung. Full article

The presence of laryngeal disease affects vocal fold(s) dynamics and thus causes changes in pitch, loudness, and other characteristics of the human voice. Many frameworks based on the acoustic analysis of speech signals have been created in recent years; however, they are evaluated on just one or two corpora and are not independent to voice illnesses and human bias. In this article, a unified wavelet-based paradigm for evaluating voice diseases is presented. This approach is independent of voice diseases, human bias, or dialect. The vocal folds’ dynamics are impacted by the voice disorder, and this further modifies the sound source. Therefore, inverse filtering is used to capture the modified voice source. Furthermore, the fundamental frequency independent statistical and energy metrics are derived from each spectral sub-band to characterize the retrieved voice source. Speech recordings of the sustained vowel /a/ were collected from four different datasets in German, Spanish, English, and Arabic to run the several intra and inter-dataset experiments. The classifiers’ achieved performance indicators show that energy and statistical features uncover vital information on a variety of clinical voices, and therefore the suggested approach can be used as a complementary means for the automatic medical assessment of voice diseases. Full article