Abstract
This study mapped the variation in tissue elasticity of the subglottic mucosa, applied these data to provide initial models of the likely deformation of the mucosa during the myoelastic cycle, and hypothesized as to the impact on the process of phonation. Six donor human larynges were dissected along the sagittal plane to expose the vocal folds and subglottic mucosa. A linear skin rheometer was used to apply a controlled shear force, and the resultant displacement was measured. These data provided a measure of the stress/strain characteristics of the tissue at each anatomic point. A series of measurements were taken at 2-mm interval inferior of the vocal folds, and the change in elasticity was determined. It was found that the elasticity of the mucosa in the subglottic region increased linearly with distance from the vocal folds in all 12 samples. A simple deformation model indicated that under low pressure conditions the subglottic mucosa will deform to form a cone, which could result in a higher velocity, thus amplifying the low pressure effect resulting from the Venturi principle, and could assist in maintaining laminar flow. This study indicated that the deformation of the subglottic mucosa could play a significant role in the delivery of a low pressure airflow over the vocal folds. A large scale study will now be undertaken to secure more data to evaluate this hypothesis, and using computational fluid dynamics based on actual three-dimensional structure obtained from computed tomography scans the aerodynamics of this region will be investigated.
Highlights
The principles underlying the ability to phonate are well established.[1]
Our reason for examining this region is that the subglottic region is rarely studied due to the difficulty in visualization, some studies have indicated that it may play a role in phonation, and that scarring in this region could affect the quality of voice
Variation in mucosal stiffness This preliminary study indicated that there is a variation in the elastic properties of the subglottic mucosa, with tissue stiffness increasing as the measurements were taken in a more inferior direction
Summary
The principles underlying the ability to phonate are well established.[1] The purpose of this study was to focus on the tissue structures in the subglottic region that are less well studied. Previous studies[2,3] indicated that the stiffness of subglottic mucosa in pig and canine larynges increased with distance inferior from the vocal folds. The team deployed a linear skin rheometer (LSR), as used in comparable studies by other teams who were examining the elastic properties of vocal fold tissue.[4,5]. Our reason for examining this region is that the subglottic region is rarely studied due to the difficulty in visualization, some studies have indicated that it may play a role in phonation, and that scarring in this region could affect the quality of voice. Both studies indicate that the subglottal region does play a role in phonation, and this study was devised to gain a better understanding of how that region functions during phonation, and to see if the biomechanics could explain these reported impacts
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
