Otolaryngology: Open Access
Open Access

Vocal Folds: Phonatory system: Speech: Singing: Biomechanics: Voice Disorders: Laryngology

Introduction

The vocal folds, also known as vocal cords, play a central role in voice production. They consist of two folds of mucous membrane stretched horizontally across the larynx and are capable of vibrating to produce sound. Disorders affecting the vocal folds can significantly impact an individual's quality of life, leading to difficulties in communication and social interaction [1]. Therefore, there is a growing need for research aimed at understanding the underlying mechanisms of vocal fold function and dysfunction. This manuscript aims to review the methodological approaches used in experiments related to vocal folds in the field of laryngology [2].

In vivo studies: In vivo studies involve conducting experiments on living organisms, typically humans or animals. Various imaging modalities, such as laryngeal videostroboscopy, high-speed video endoscopy, and magnetic resonance imaging (MRI), are commonly used to visualize the vocal folds in vivo [3]. These techniques allow researchers to observe vocal fold vibration patterns, mucosal wave propagation, and structural abnormalities in real-time. Additionally, electromyography (EMG) can be used to record muscle activity associated with vocal fold movement, providing insights into neuromuscular control mechanisms. In vivo studies also include clinical trials aimed at evaluating the effectiveness of therapeutic interventions for voice disorders, such as surgical techniques or voice therapy protocols [4].

In vitro studies: In vitro studies involve conducting experiments on excised laryngeal tissue or vocal fold models under controlled laboratory conditions. These experiments allow researchers to investigate specific biomechanical properties of the vocal folds, such as tissue viscoelasticity, mucosal wave dynamics, and vocal fold vibration characteristics [5]. Techniques such as laryngeal micro dissection, tensile testing, and high-speed imaging of vocal fold oscillation are commonly used in vitro. In vitro studies provide valuable insights into the underlying physiology of the vocal folds and can help validate computational models of vocal fold biomechanics.

Computational modeling: Computational modeling plays an increasingly important role in understanding vocal fold behavior and simulating various physiological and pathological conditions. Finite element analysis (FEA) and computational fluid dynamics (CFD) are two commonly used modeling techniques in laryngology [6]. FEA allows researchers to simulate the mechanical behavior of the vocal folds under different loading conditions, while CFD can be used to model airflow patterns and aerodynamic forces during phonation. These computational models can help elucidate the complex interactions between vocal fold structure, airflow, and acoustic output, aiding in the diagnosis and treatment of voice disorders [7].

Advantages and limitations: Each methodological approach has its own advantages and limitations. In vivo studies provide valuable clinical insights into vocal fold function but are limited by ethical considerations and variability among human subjects. In vitro studies offer greater control over experimental conditions but may not fully replicate the dynamic environment of the human larynx [8,9]. Computational modeling allows for virtual experimentation and hypothesis testing but relies on simplifications and assumptions that may not fully capture the complexity of vocal fold physiology. Integrating multiple approaches and combining experimental data with computational simulations can enhance our understanding of vocal fold mechanics and improve diagnostic and therapeutic strategies for voice disorders [10].

Future Directions

Advances in technology and interdisciplinary collaboration hold promise for future research in vocal fold experimentation. Emerging imaging techniques, such as optical coherence tomography (OCT) and dynamic MRI, offer higher spatial and temporal resolution for studying vocal fold dynamics. Biomechanical modeling approaches, including multi-scale modeling and patient-specific simulations, can provide personalized insights into voice disorders and treatment outcomes. Furthermore, incorporating machine learning algorithms and artificial intelligence methods may facilitate automated analysis of vocal fold images and improve diagnostic accuracy. By continually refining methodological approaches and integrating complementary techniques, researchers can make significant strides in unraveling the mysteries of vocal fold function and dysfunction.

Conclusion

Experimentation on vocal folds in laryngology encompasses a diverse range of methodological approaches, including in vivo studies, in vitro experiments, and computational modeling. Each approach offers unique insights into vocal fold mechanics and behavior, contributing to our understanding of voice production and disorders. By combining experimental data with computational simulations and leveraging advances in technology, researchers can further elucidate the complex interplay between vocal fold structure, function, and pathology. Ultimately, this knowledge can lead to improved diagnostic techniques, innovative therapeutic interventions, and enhanced quality of life for individuals with voice disorders.

Acknowledgment

None

Conflict of Interest

None

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