The air flow to the lungs is disturbed by a partial or complete collapse of the upper airways of patients suffering from Obstructive Sleep Apnea. Numerical simulations on patient specific models may be used to extract pathophysiological parameters like flow velocity and pressure distribution in the human pharynx and can evaluate the severity of the disease and the success of a therapy. In this work, Computational Fluid Dynamics are used to simulate the air flow in the natural pharyngeal geometry of a patient as well as in the deformed pharyngeal geometry of the same patient treated with a...