Computational assessment of incremental pyriform aperture enlargement in plastic surgery: effect on inhaled nasal airflow
Background. The pyriform aperture is a critical anterior bony constriction governing nasal airflow and is clinically relevant to both functional and aesthetic nasal surgery, yet the degree of pyriform aperture enlargement (PAE) needed to capture its aerodynamic benefit is undefined. This study employs high-fidelity computational fluid dynamics (CFD) to quantify the aerodynamic effects of progressive PAE and identify a threshold beyond which further enlargement yields minimal benefit. Methods. A CT-derived three-dimensional nasal airway model was digitally modified to produce baseline, 5%, 10%, 15%, and 20% increases in pyriform aperture cross-sectional area. Pressure-driven large-eddy simulations (LES) were performed at a fixed transnasal pressure difference of 11.25 Pa to quantify changes in inspiratory flow rate, total airway resistance, and local airflow characteristics. Results. Progressive PAE monotonically increased inspiratory flow from 15.063 to 15.252 L/min (approximately 1.25%) and reduced airway resistance from 0.6138 to 0.6028 Pa.min/L (approximately 1.80%). The aerodynamic response was strongly nonlinear, with the greatest improvement occurring between 10% and 15% enlargement. Increasing the aperture from 15% to 20% produced negligible additional improvement. Conclusions. PAE improves nasal airflow by reducing the resistance imposed by the anterior bony constriction. In the anatomical model investigated, approximately 15% area enlargement represented an efficient aerodynamic threshold, after which the dominant resistance shifted toward downstream nasal structures and further enlargement produced little additional benefit. These findings support a conservative, anatomy-dependent approach to PAE and warrant validation across a broader range of patient-specific geometries.