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AJNR. American Journal of Neuroradiology Apr 2022Several CT findings are thought to be indicative of vocal cord paralysis; however, these signs have never been validated in a blinded fashion. This study attempts to...
BACKGROUND AND PURPOSE
Several CT findings are thought to be indicative of vocal cord paralysis; however, these signs have never been validated in a blinded fashion. This study attempts to compare and validate these signs and determine their accuracy in predicting vocal cord paralysis.
MATERIALS AND METHODS
A retrospective chart review was performed, and CT scans from patients with known unilateral vocal cord paralysis and known normal vocal cord movement were reviewed by 3 radiologists who were blinded to the status of the patients' laryngeal function. The scans were reviewed and scored for 8 accepted signs of vocal cord paralysis as well as for predicting a final diagnostic conclusion. Statistical analysis using odds ratios for signs and the Fleiss κ for criterion agreement among the radiologists was performed for diagnostic accuracy.
RESULTS
The presence of medial displacement of the posterior ipsilateral vocal fold margin and ipsilateral laryngeal ventricular dilation yielded the greatest positive predictive value. Other signs demonstrated high specificity, but interrater discrepancy was greater than expected and diminished the reliability of these signs in predicting vocal cord paralysis. Overall, sensitivity and negative predictive values were low.
CONCLUSIONS
Predicting vocal cord paralysis on the basis of CT findings is not as accurate or straightforward in prospectively predicting vocal cord paralysis as implied in prior studies.
Topics: Humans; Reproducibility of Results; Retrospective Studies; Tomography, X-Ray Computed; Vocal Cord Paralysis; Vocal Cords
PubMed: 35332018
DOI: 10.3174/ajnr.A7451 -
Journal of Voice : Official Journal of... May 2023The understanding of vocal fold hydration state, including dehydrated, euhydrated, rehydrated tissue, and how hydration affects vocal fold biomechanical properties is...
OBJECTIVES
The understanding of vocal fold hydration state, including dehydrated, euhydrated, rehydrated tissue, and how hydration affects vocal fold biomechanical properties is still evolving. Although clinical observations support the benefits of increasing vocal fold hydration after dehydrating events, more mechanistic information on the effects of vocal fold dehydration and the beneficial effects of rehydration are needed. Alterations to hyaluronic acid (HA), an important component of the vocal fold extracellular matrix, are likely to influence the biomechanical properties of vocal folds. In this study, we investigated the influence of hydration state and HA on vocal fold tissue stiffness via biomechanical testing.
STUDY DESIGN
Prospective, ex vivo study design.
METHODS
Fresh porcine vocal folds (N = 18) were examined following sequential immersion in hypertonic (dehydration) and isotonic solutions (rehydration). In a separate experiment, vocal folds were incubated in hyaluronidase (Hyal) to remove HA. Control tissues were not exposed to any challenges. A custom micromechanical system with a microforce sensing probe was used to measure the force-displacement response. Optical strain was calculated, and ultrasound imaging was used to measure tissue cross-sectional area to obtain stress-strain curves.
RESULTS
Significant increases (P ≤ 0.05) were found in tangent moduli between dehydrated and rehydrated vocal folds at strains of ε = 0.15. The tangent moduli of Hyal-digested tissues significantly increased at both ε = 0.15 and 0.3 (P ≤ 0.05).
CONCLUSION
Vocal fold dehydration increased tissue stiffness and rehydration reduced the stiffness. Loss of HA increased vocal fold stiffness, suggesting a potential mechanical role for HA in euhydrated vocal folds.
Topics: Swine; Animals; Vocal Cords; Biomechanical Phenomena; Dehydration; Hyaluronoglucosaminidase; Prospective Studies
PubMed: 33541766
DOI: 10.1016/j.jvoice.2021.01.014 -
Materials Science & Engineering. C,... Jul 2016The human vocal folds are complex structures made up of distinct layers that vary in cellular and extracellular composition. The mechanical properties of vocal fold... (Review)
Review
The human vocal folds are complex structures made up of distinct layers that vary in cellular and extracellular composition. The mechanical properties of vocal fold tissue are fundamental to the study of both the acoustics and biomechanics of voice production. To date, quantitative methods have been applied to characterize the vocal fold tissue in both normal and pathologic conditions. This review describes, summarizes, and discusses the most commonly employed methods for vocal fold biomechanical testing. Force-elongation, torsional parallel plate rheometry, simple-shear parallel plate rheometry, linear skin rheometry, and indentation are the most frequently employed biomechanical tests for vocal fold tissues and each provide material properties data that can be used to compare native tissue to diseased or treated tissue. Force-elongation testing is clinically useful, as it allows for functional unit testing, while rheometry provides physiologically relevant shear data, and nanoindentation permits micrometer scale testing across different areas of the vocal fold as well as whole organ testing. Thoughtful selection of the testing technique during experimental design to evaluate a hypothesis is critical to optimize biomechanical testing of vocal fold tissues.
Topics: Biomechanical Phenomena; Humans; Models, Biological; Vocal Cords
PubMed: 27127075
DOI: 10.1016/j.msec.2016.04.018 -
The Journal of Experimental Biology Apr 2022Acoustic allometry occurs when features of animal vocalisations can be predicted from body size measurements. Despite this being considered the norm, allometry sometimes...
Acoustic allometry occurs when features of animal vocalisations can be predicted from body size measurements. Despite this being considered the norm, allometry sometimes breaks, resulting in species sounding smaller or larger than expected for their size. A recent hypothesis suggests that allometry-breaking mammals cluster into two groups: those with anatomical adaptations to their vocal tracts and those capable of learning new sounds (vocal learners). Here, we tested which mechanism is used to escape from acoustic allometry by probing vocal tract allometry in a proven mammalian vocal learner, the harbour seal (Phoca vitulina). We tested whether vocal tract structures and body size scale allometrically in 68 young individuals. We found that both body length and body mass accurately predict vocal tract length and one tracheal dimension. Independently, body length predicts vocal fold length while body mass predicts a second tracheal dimension. All vocal tract measures are larger in weaners than in pups and some structures are sexually dimorphic within age classes. We conclude that harbour seals do comply with anatomical allometric constraints. However, allometry between body size and vocal fold length seems to emerge after puppyhood, suggesting that ontogeny may modulate the anatomy-learning distinction previously hypothesised as clear cut. We suggest that seals, and perhaps other species producing signals that deviate from those expected from their vocal tract dimensions, may break allometry without morphological adaptations. In seals, and potentially other vocal learning mammals, advanced neural control over vocal organs may be the main mechanism for breaking acoustic allometry.
Topics: Acoustics; Animals; Body Size; Mammals; Vocal Cords; Vocalization, Animal
PubMed: 35483405
DOI: 10.1242/jeb.243766 -
Biomedical Engineering Online Aug 2023In this study, we proposed a deep learning technique that can simultaneously detect suspicious positions of benign vocal cord tumors in laparoscopic images and classify...
BACKGROUND
In this study, we proposed a deep learning technique that can simultaneously detect suspicious positions of benign vocal cord tumors in laparoscopic images and classify the types of tumors into cysts, granulomas, leukoplakia, nodules and polyps. This technique is useful for simplified home-based self-prescreening purposes to detect the generation of tumors around the vocal cord early in the benign stage.
RESULTS
We implemented four convolutional neural network (CNN) models (two Mask R-CNNs, Yolo V4, and a single-shot detector) that were trained, validated and tested using 2183 laryngoscopic images. The experimental results demonstrated that among the four applied models, Yolo V4 showed the highest F1-score for all tumor types (0.7664, cyst; 0.9875, granuloma; 0.8214, leukoplakia; 0.8119, nodule; and 0.8271, polyp). The model with the lowest false-negative rate was different for each tumor type (Yolo V4 for cysts/granulomas and Mask R-CNN for leukoplakia/nodules/polyps). In addition, the embedded-operated Yolo V4 model showed an approximately equivalent F1-score (0.8529) to that of the computer-operated Yolo-4 model (0.8683).
CONCLUSIONS
Based on these results, we conclude that the proposed deep-learning-based home screening techniques have the potential to aid in the early detection of tumors around the vocal cord and can improve the long-term survival of patients with vocal cord tumors.
Topics: Humans; Vocal Cords; Neural Networks, Computer; Computer Simulation; Cysts; Leukoplakia
PubMed: 37596652
DOI: 10.1186/s12938-023-01139-2 -
Scientific Reports Jun 2021Vocal fold (VF) fibrosis is a major cause of intractable voice-related disability and reduced quality of life. Excision of fibrotic regions is suboptimal and associated...
Vocal fold (VF) fibrosis is a major cause of intractable voice-related disability and reduced quality of life. Excision of fibrotic regions is suboptimal and associated with scar recurrence and/or further iatrogenic damage. Non-surgical interventions are limited, putatively related to limited insight regarding biochemical events underlying fibrosis, and downstream, the lack of therapeutic targets. YAP/TAZ integrates diverse cell signaling events and interacts with signaling pathways related to fibrosis, including the TGF-β/SMAD pathway. We investigated the expression of YAP/TAZ following vocal fold injury in vivo as well as the effects of TGF-β1 on YAP/TAZ activity in human vocal fold fibroblasts, fibroblast-myofibroblast transition, and TGF-β/SMAD signaling. Iatrogenic injury increased nuclear localization of YAP and TAZ in fibrotic rat vocal folds. In vitro, TGF-β1 activated YAP and TAZ in human VF fibroblasts, and inhibition of YAP/TAZ reversed TGF-β1-stimulated fibroplastic gene upregulation. Additionally, TGF-β1 induced localization of YAP and TAZ in close proximity to SMAD2/3, and nuclear accumulation of SMAD2/3 was inhibited by a YAP/TAZ inhibitor. Collectively, YAP and TAZ were synergistically activated with the TGF-β/SMAD pathway, and likely essential for the fibroplastic phenotypic shift in VF fibroblasts. Based on these data, YAP/TAZ may evolve as an attractive therapeutic target for VF fibrosis.
Topics: Adaptor Proteins, Signal Transducing; Animals; Female; Fibrosis; Humans; Intracellular Signaling Peptides and Proteins; Rats; Rats, Sprague-Dawley; Signal Transduction; Smad Proteins; Transcription Factors; Transcriptional Coactivator with PDZ-Binding Motif Proteins; Vocal Cord Dysfunction; Vocal Cords; YAP-Signaling Proteins
PubMed: 34188130
DOI: 10.1038/s41598-021-92871-z -
European Archives of... Mar 2022We investigated the role of Glut-1 and H/K-ATPase expression in pepsin-induced development of human vocal cord leukoplakia cells (HVCLCs). Next, we analyzed the...
PURPOSE
We investigated the role of Glut-1 and H/K-ATPase expression in pepsin-induced development of human vocal cord leukoplakia cells (HVCLCs). Next, we analyzed the relationship between Glut-1 and H/K-ATPase expression with the clinicopathological features of laryngeal carcinoma.
METHODS
Glut-1 and H/K-ATPase expression levels in HVCLCs were determined after treatment with artificial gastric juice containing pepsin and laryngeal carcinoma tissues.
RESULTS
Exposure to pepsin-containing artificial gastric juice significantly enhanced the migration and proliferation of VSCLCs in a time-dependent manner. The apoptotic rate of VSCLCs decreased over time after exposure to pepsin and reached a nadir on day 7 (p < 0.01). With increasing duration of exposure to pepsin, the proportion of VSCLCs in G0/G1 phase decreased and the proportions in the S and G2/M phases significantly increased (p < 0.05). After treatment with pepsin-containing artificial gastric juice, RT-PCR and Western blotting showed that the expression of Glut-1 and H/K-ATPase α, β significantly increased in HVCLCs compared to in the absence of pepsin (p < 0.05). The expression of Glut-1 and H/K-ATPase α, β gradually increased from vocal cord leukoplakia (VLC) to laryngeal carcinoma (p < 0.05). Lentivirus-mediated inhibition of Glut-1 expression in VCL significantly inhibited the cells' migration and proliferation (p < 0.05) but enhanced their apoptosis (p < 0.05). Also, inhibition of Glut-1 expression resulted in an increased proportion of cells in G0/G1 phase and a significantly decreased proportion in G2/M phase (p < 0.05).
CONCLUSIONS
Elevated Glut-1 expression may promote the development of VCL by upregulating laryngeal H/K-ATPase expression to reactivate absorbed pepsin, thus damaging the laryngeal mucosa.
Topics: Adenosine Triphosphatases; Glucose Transporter Type 1; H(+)-K(+)-Exchanging ATPase; Humans; Laryngeal Neoplasms; Laryngopharyngeal Reflux; Leukoplakia; Pepsin A; Vocal Cords
PubMed: 34800155
DOI: 10.1007/s00405-021-07172-y -
Respirology (Carlton, Vic.) Aug 2019
Topics: Humans; Patient Care Team; Vocal Cord Dysfunction; Vocal Cords
PubMed: 30977222
DOI: 10.1111/resp.13560 -
Proteomics. Clinical Applications Mar 2022The vast majority of voice disorders is associated with changes of the unique, but delicate, human vocal fold mucosa. The ability to develop new effective treatment...
The vast majority of voice disorders is associated with changes of the unique, but delicate, human vocal fold mucosa. The ability to develop new effective treatment methods is significantly limited by the physical inaccessibility and the extremely rare occasions under which healthy tissue biopsies can be obtained. Therefore, the interest in laryngological research has shifted to human oral (buccal) mucosa, a similar and more easily available tissue. The harvesting process is less invasive and accompanied with faster healing and less scarring, compared to vocal fold mucosa. Here we report a descriptive proteomic comparison of paired human buccal and vocal fold mucosa by high-resolution mass spectrometry (CID-MS/MS). Our study identified a total of 1575 proteins detected within both tissues that are highly consistent in several crucial biological processes, cellular components, and molecular functions. Hence, our proteomic analysis will provide a fundamental resource for the laryngological research community.
Topics: Cicatrix; Humans; Mouth Mucosa; Proteomics; Tandem Mass Spectrometry; Vocal Cords
PubMed: 34792860
DOI: 10.1002/prca.202100050 -
Journal of Biomedical Optics Aug 2023The vocal folds are critically important structures within the larynx which serve the essential functions of supporting the airway, preventing aspiration, and phonation....
SIGNIFICANCE
The vocal folds are critically important structures within the larynx which serve the essential functions of supporting the airway, preventing aspiration, and phonation. The vocal fold mucosa has a unique multilayered architecture whose layers have discrete viscoelastic properties facilitating sound production. Perturbations in these properties lead to voice loss. Currently, vocal fold pliability is inferred clinically using laryngeal videostroboscopy and no tools are available for objective assessment.
AIM
The main objective of the present study is to evaluate viability of Brillouin microspectroscopy for differentiating vocal folds' mechanical properties against surrounding tissues.
APPROACH
We used Brillouin microspectroscopy as an emerging optical imaging modality capable of providing information about local viscoelastic properties of tissues in noninvasive and remote manner.
RESULTS
Brillouin measurements of the porcine larynx vocal folds were performed. Elasticity-driven Brillouin spectral shifts were recorded and analyzed. Elastic properties, as assessed by Brillouin spectroscopy, strongly correlate with those acquired using classical elasticity measurements.
CONCLUSIONS
These results demonstrate the feasibility of Brillouin spectroscopy for vocal fold imaging. With more extensive research, this technique may provide noninvasive objective assessment of vocal fold mucosal pliability toward objective diagnoses and more targeted treatments.
Topics: Animals; Swine; Vocal Cords; Larynx; Phonation; Elasticity; Spectrum Analysis
PubMed: 37560326
DOI: 10.1117/1.JBO.28.8.087002