ABSTRACT
<p><b>OBJECTIVE</b>To investigate the relationship between the maxillary sinus flow field, temperature field and the maxillary sinus ostium size, and to provide a reference for endoscopic surgery according to the maxillary sinus scope.</p><p><b>METHODS</b>One case of adult female CT image data was obtained, and used to build a three-dimensional model of nasal cavity and maxillary sinus. Computational fluid dynamics method was used to study the airflow and temperature of the maxillary sinus, as well as the physiological function of the maxillary sinus. Simulation surgery by means of different maxillary sinus diameters (normal, 8 mm, 10 mm, 12 mm and 15 mm) was used to describe the maxillary sinus airflow and temperature change.</p><p><b>RESULTS</b>It was found that by numerical simulation the airflow of maxillary sinus and nasal cavity showed lower speed (average speed 0.062 m/s) than that in the middle nasal meatus (average speed of 3.260 m/s), and the average temperature in the normal maxillary sinus was 34°C, which was higher than that in the middle nasal meatus (temperature 28.7°C). With the increase of the diameter of the maxillary sinus, the air temperature change was not obvious.</p><p><b>CONCLUSIONS</b>The physiological function of the maxillary sinus can be studied through the numerical simulation. With the increase of the ostia diameter of maxillary sinus, the sinus temperature and ventilation is not affected. It provides a reference for quantification of clinical endoscopic maxillary sinus surgery.</p>