Creation of a standardized geometry of the human nasal cavity.

A novel, standardized geometry of the human nasal cavity was created by aligning and processing 30 sets of computed tomography (CT) scans of nasal airways of healthy subjects. Digital three-dimensional (3-D) geometries of the 60 single human nasal cavities (30 right and 30 mirrored left cavities) were generated from the CT scans and measurements of physical parameters of each single nasal cavity were performed. A methodology was developed to scale, orient, and align the nasal geometries, after which 2-D digital coronal cross-sectional slices were generated. With the use of an innovative image processing algorithm, median cross-sectional geometries were created to match median physical parameters while retaining the unique geometric features of the human nasal cavity. From these idealized 2-D images, an original 3-D standardized median human nasal cavity was created. This new standardized geometry was compared against the original geometries of all subjects as well as limited existing data from the literature. The new model has potential for use as a geometric standard in future experimental and numerical studies of deposition of inhaled aerosols, as well as for use as a reference during diagnosis of unhealthy patients. The specific procedure developed could also be applied to build standard nasal geometries for different identifiable groups within the larger population.