Computational Analysis Investigating Intranasal Drug Delivery Following Functional Septorhinoplasty

Introduction: Effectiveness of topical intranasal medications, often prescribed to address various sinonasal diseases, is limited by ability to penetrate posteriorly to target site. This study investigates the effect of functional septorhinoplasty addressing nasal valve collapse on nebulized drug delivery to the posterior nasal airway.

Methods: Three fresh cadaveric heads underwent septoplasty, dorsal preservation rhinoplasty (DPR), and butterfly graft (BFG) placement. Pre- and post-intervention radiographic images were used to create nasal airway models. Resting inspiratory and drug delivery simulations were performed using 1-30µm particle sizes, for 1 and 5m/s particle velocities. Posterior airway drug particle depositions were calculated for particle sizes: 1-10µm, 11-20µm, and 21-30µm.

Results: Preoperatively, 11-20µm particles had the greatest average posterior deposition 4.0% for both velocities. Post-septoplasty, posterior deposition increased across all particle sizes but remained greatest for medium particles (1 m/s=9.0%; 5 m/s=8.3%). Regardless of velocity, deposition decreased with DPR alone and DPR+BFG for small and medium particles while increasing for large particles. At 1 m/s, average posterior deposition was greatest for 11-20µm with DPR alone (7.3%) but 21-30µm particles with DPR+BFG (10.0%). At 5 m/s, 21-30µm had greatest average posterior deposition for both DPR alone (8.8%) and DPR+BFG (12.8%).

Conclusions: Nebulized delivery to the posterior nasal cavity improved across all particle sizes after septoplasty, while DPR alone and DPR+BFG improved posterior deposition for large particles, with greater deposition at 5m/s. Our preliminary findings indicate that septorhinoplasty improves drug delivery to posteriorly for 21-30µm particles.