A study of fluid dynamics parameters for prediction of obstructive sleep apnea

Obstructive sleep apnea (OSA) is a syndrome characterized by the repetitive episodic collapse of the upper airway. The purpose of this study is to investigate the fluid dynamic parameters for the prediction of obstructive sleep apnea in the upper airway before and after setback surgery. Here, we analyzed the flow phenomena of inspiration and expiration in obstructive sleep apnea patients. The modeling of the upper airway was performed with facial 3 dimensional facial computed tomography images (3D facial CT). We used timedependent value for boundary conditions. The changes of pressure were studied with 3D facial CT taken both before and after the setback surgery. Further, it was found that the correlation between PSG data and non-dimensional pressure drop can be used to predict the severity of OSA. In all 6 patients except for patient 1, the average values of the non-dimensional pressure drops and PSG clinical data are inversely related. For each patient, the lower the pressure drop is, the higher the PSG values will be.