Effect of breathing profiles on nebuliser drug delivery targeting the paranasal sinuses in a post-operative nasal cavity

Abstract

Chronic rhinosinusitis (CRS) is a common sinonasal condition that debilitates quality of life. Nasal sprays are inefficient for targeting the sinuses because of the highly inertial atomised droplets. This study evaluated sinus drug delivery via a nebuliser in a human nasal cavity using Computational Fluid Dynamics (CFD) simulations of different breathing conditions. The nebuliser was quantified through high-speed imaging of the spray plume and average velocity, while laser diffraction was used for droplet size distributions. A CT scan was acquired of a 75-year-old male with a confirmed diagnosis of CRS, and airway segmentation was performed to extract the nasal cavity and sinuses. Virtual surgery was then performed on the computational model. Two nozzle designs for the nebuliser under normal breathing, slow exhalation, and breath hold were investigated. The results demonstrated that drug delivery with a fully blocked nostril with a breath hold notably improved deposition targeting the maxillary sinuses and ethmoid sinuses, while using a nozzle that allowed co-flow of air was recommended for targeting the frontal and sphenoid sinuses.