Quantification of Fluid Structure Interaction Dynamics in a Deformable Vocal Fold Model with Injected Materials

Utah State University

The influence of injections on the fluid structure interactions was evaluated on a deformable life sized, synthetic, self-oscillating model with idealized geometry of human vocal folds. Two models were designed to incorporate 10% and 20% bowing similar to that found in patients with vocal fold paralysis. The models were fabricated from a flexible silicone compound with Young’s modulus values similar to those found in human vocal folds. The models incorporated a two-layer design that simulated the layered vocal fold structure. The bowed models were paired with “healthy” models and injected with silicone material until the gap from the designed bowing was closed. The effects of the injections were compared by measuring flow rate, frequency, onset pressure (a measure of vocal effort), and maximum glottal gap. High-speed imaging of the superior surface was used to determine qualitative data on the oscillation pattern. Flow rate, onset pressure, and maximum glottal gap were all reduced after injections were placed for both bowing cases. Frequency increased for the 10% bowed case and remained unchanged for the 20% bowed case. Suggestions for future related studies are discussed.