  Obstructive sleep apnea syndrome is now considered as a major health care
topic. An in-vitro setup which reproduces and simplifies upper airway geometry
has been the basis to study the fluid/walls interaction that leads to an apnea.
It consists of a rigid pipe (the pharynx) in contact with a deformable latex
cylinder filled with water (the tongue). Air flows out of the rigid pipe and
induces pressure forces on the cylinder. We present a numerical model of this
setup: a finite element model of the latex cylinder is in interaction with a
fluid model. Simulation of an hypopnea (partial collapsus of the airway) has
been possible and in agreement with observations from the in-vitro setup. The
same phenomenon has been simulated on a soft palate model obtained from a
patient sagittal radiography. These first results encourage us to improve the
model so as it could reproduce the complete apnea phenomenon, and be used for a
planification purpose in sleep apnea surgery.
