Gender Differences in Nasal Anatomy and Function Among Caucasians

Background: Anatomical variations influence nasal physiology, yet sex differences in physiology remains unclear. Objective: To investigate sex differences among Caucasians using computational fluid dynamics. Methods: Adult subjects were selected with normal nasal cone beam computed tomography (CBCT) images and Nasal Obstruction Symptom Evaluation scores ≤30. The CBCT images were used to create subject-specific airway models. Nasal surface area (SA) and volume were computed, and airflow and heat transfer were simulated. Results: The CBCT scans were taken from 23 females and 12 males. The SA and volume (males: mean = 25.0 cm³; females: mean = 19.5 cm³; p < 0.001; Cohen's d = 1.51) were significantly larger for males, but SA-to-volume ratio did not differ significantly. Although unilateral nasal resistance did not vary greatly, females had higher bilateral resistance (males: mean = 0.04 Pa.s/mL; females: mean = 0.05 Pa.s/mL; p = 0.044; Cohen's d = 0.37). Females had higher heat flux (males: mean = 158.5 W/m²; females: mean = 191.8 W/m²; p = 0.012; Cohen's d = 0.79), but males had larger SA where mucosal heat flux exceeds 50 W/m². Conclusions: These findings suggest differences in normal nasal anatomy and physiology between Caucasian males and females, which may be useful when assessing sex-specific functional outcomes after nasal surgery.