Influence of Nasal Passage Geometry on Aerosol Particle Deposition in the Nose

Nasal passage particle deposition has been measured in ten adult, normal subjects with a well-described aerosol (MMAD=2.6 μm) and compared with nasal resistance and dimensional measurements made simultaneously. Studies were performed with both normal and drug decongested nasal airways to determine the effect of changing dimension and resistance on overall and local nasal passage deposition. Significant intersubject variability was observed which was not well correlated with minimum nasal area, nasal volume, or resistance. Decongestion was found to increase overall deposition percent. A major portion of the aerosol deposited in the anterior, non-ciliated region of the nose, from which it can be removed manually. The findings suggest that intersubject variability in upper respiratory deposition percent among normals is much greater than variability in intrathoracic deposition fractions.