Simulation of the Retroglossal Fluid-Structure Interaction During Obstructive Sleep Apnea

A method for computing the interaction between the airflow and the soft tissue during an Obstructive Apnea is presented. It is based on simplifications of the full continuum formulation (NavierStokes and finite elasticity) to ensure computation time compatible with clinical applications. Linear elasticity combined with a precomputation method allows fast prediction of the tissue deformation, while an asymptotic formulation of the full Navier-Stokes equations (Reduced NavierStokes/Prandtl equations) has been chosen for the flow. The accuracy of the method has already been assessed experimentally. Then, simulations of the complete collapsus at the retroglossal level in the upper airway have been carried out, on geometries extracted from pre-operative radiographies of two apneic patients. Post-operative geometries have been also used to check qualitatively if the predictions from the simulations are in agreement with the effects of the surgery.