Unilateral vocal fold paralysis (UVFP) can present with structural asymmetries in left-right position of the membranous folds, vocal fold height, length, tension, and arytenoid position. Surgically there is often controversy on how to restore optimal vocal function. Work in our previous R01 showed vortices form in the superior aspect of the divergent glottis during closing, and are associated with changes in the flow rate such as greater flow skewing (previously thought to be only caused by increased vocal tract inertance), and with favorable effects on loudness and intelligibility. Thus we hypothesize a better understanding of these vortices, and their effect on flow rate and acoustics, will open up a new paradigm to evaluate and design new surgical interventions for unilateral paralysis and other conditions featuring structural asymmetries. So far our findings are based on two-dimensional (2D) measurements whereas intraglottal geometry and flow rate change in all three-dimensions (3D). The extention of our technique from 2D to 3D will allow completion of the following specific aims:
Specific Aim 1. Using a combination of computational and excised canine larynx models, characterize the effects of vocal tract inertance, intraglottal vortices and tissue elasticity on te medial surface dynamics of the folds, volumetric flow rate at the glottal exit, and acoustics in th following models: 1A. Excised canine larynx with relative symmetry in vocal fold length, height, and stiffness. 1B. Excised canine larynx with asymmetries in vocal fold length, height, and stiffness. 1C. Excised canine larynges that have a Thyroplasty Type I with various implant shapes and degrees of infraglottal medialization. 1D. Excised canine larynges that have Thyroplasty Type I with and without arytenoid adduction.
Specific Aim 2. Volumetric flow rate will be measured directly at the glottal exit using volumetric particle imaging velocimetry and indirectly at the mouth using inverse filtering in an excised canine larynx model with a mechanical vocal tract.
There is currently no consensus on optimal treatment for unilateral vocal fold paralysis; one main reason for this is a lack of understanding of the underlying mechanisms of how structural asymmetries found in unilateral paralysis, and the surgical treatments designed to correct these asymmetries, affect voice production. This proposal will elucidate these mechanisms using innovative methodology.
| Oren, Liran; Khosla, Sid; Gutmark, Ephraim (2016) Effect of vocal fold asymmetries on glottal flow. Laryngoscope 126:2534-2538 |
| Farbos de Luzan, Charles; Chen, Jie; Mihaescu, Mihai et al. (2015) Computational study of false vocal folds effects on unsteady airflows through static models of the human larynx. J Biomech 48:1248-57 |
| Oren, Liran; Gutmark, Ephraim; Khosla, Sid (2015) Intraglottal velocity and pressure measurements in a hemilarynx model. J Acoust Soc Am 137:935-43 |
| Oren, Liran; Khosla, Sid; Gutmark, Ephraim (2015) Comparison of glottal flow rate characteristics based on experimental and computational data. J Acoust Soc Am 138:2427-9 |
| Oren, Liran; Khosla, Sid; Dembinski, Doug et al. (2015) Direct measurement of planar flow rate in an excised canine larynx model. Laryngoscope 125:383-8 |
| Oren, Liran; Khosla, Sid; Gutmark, Ephraim (2014) Intraglottal pressure distribution computed from empirical velocity data in canine larynx. J Biomech 47:1287-93 |
| Oren, Liran; Dembinski, Doug; Gutmark, Ephraim et al. (2014) Characterization of the vocal fold vertical stiffness in a canine model. J Voice 28:297-304 |
| Khosla, Sid; Oren, Liran; Ying, Jun et al. (2014) Direct simultaneous measurement of intraglottal geometry and velocity fields in excised larynges. Laryngoscope 124 Suppl 2:S1-13 |
| Oren, Liran; Khosla, Sid; Gutmark, Ephraim (2014) Intraglottal geometry and velocity measurements in canine larynges. J Acoust Soc Am 135:380-8 |
| Mihaescu, Mihai; Khosla, Sid M; Murugappan, Shanmugam et al. (2010) Unsteady laryngeal airflow simulations of the intra-glottal vortical structures. J Acoust Soc Am 127:435-44 |
