Characterization of nasal aerodynamics and air conditioning ability using CFD and its application to improve the empty nose syndrome (ENS) submucosal floor implant surgery – Part I methodology

Background: CFD simulation allows the visualization of airflow in nasal airways, but the predictions are rarely referenced in real surgeries. The limitations include having a reliable nasal geometry with reasonable boundary conditions and how the predictions corresponding to the symptoms. Methods: The computational domain is developed from the computed tomography images and face profile of an empty nose syndrome patient with inferior turbinate reduction subtype before and after the submucosal floor implant surgery. The aerodynamics and the ability of conditioning the breathing air of the nasal cavities before and after the surgery are predicted using different breathing air conditions. Significant findings: The surgery redistributes the airflow and improves the symptoms by having higher airflow fraction in sensor-rich inferior turbinate and shear stresses on superior turbinate olfactory region. The surgery enhances heat and water vapor fluxes from the mucus rich interior turbinate. After the surgery, the surface area on disease side with heat flux greater than the threshold 50 W/m² increases at both anterior and turbinate, where receptors are rich to elevate the sense of the inhaled air. In summer and winter time, both the air temperature and relative humidity at choanae increases after the surgery by the enhanced nasal air conditioning ability.