ABSTRACT
BACKGROUND AND OBJECTIVES: Several studies have utilized physical models or casts of the nasal cavity in an effort to understand the relationship between nasal anatomy and the distribution of inspired or expired airflow. This paper deals with the evaluation of nasal airflow characteristics during physiologic breathing in normal conditions. MATERIALS AND METHOD: The choana of a nasal model casting by a combination of rapid prototyping and solidification of clear silicone was connected to a pump that simulated physiological pressure in the upper airway system. Glycerin-water mixture was used as medium. The airstream was marked with polyvinyl spherical particles, and was observed through an solidificated clear silicone and analyzed with particle image velocimetry. RESULTS: Turbulence is clearly visible at the level of the head of the middle turbinate. The maximal velocity was recorded at the superior meatus. The flow rate was highest at the middle meatus. CONCLUSION: This model allows the investigation of airflow distribution and velocity under physiologic conditions. The main flow stream passes through the middle meatus.