Computational modeling of vibration-induced systemic hydration of vocal folds over a range of phonation conditions

Predicting phonation conditions that are benign to voice health remains a biomechanically relevant problem.Our objective is to provide insight into vocal fold (VF) hydration based on continuum-based VF models thatare able to compute VF stresses during phonation and a scheme for the extraction and generalization of suchcomputational data based on the principle of linear superposition. Because VF tissue is poroelastic, spatialgradients of VF hydrostatic stresses computed for a given phonation condition determine VF interstitial fluidflow. The present approach transforms, based on linear superposition principles, the computed interstitialfluid velocities at the particular phonation to those at an arbitrary phonation condition. Intersititial fluidflow characteristics for a range of phonation conditions are compared. For phonation conditions with noor moderate collision, no dehydration per vibration cycle is predicted throughout the VF. For more severecollision conditions, tissue dehydration is restricted to a region close to the glottal surface. Interstitial fluiddisplacement in the VF is found to be heterogeneous and strongly dependent on the phonation condition.A phonation condition is found to exist for which dehydration peaks. The proposed method significantlyexpands the scope and relevance of conducting isolated numerical simulations of VF vibration.