Standardization of nasal airway structure model of Chinese Han nationality for characterization of nasal formulation spatial deposition atlases.

The deposition characteristics of nasal formulations directly determine the efficacy of the drugs, whilst the complexity of human nasal airway structure encumbers quantitative evaluation of nasal spatial deposition. Male and female standard nasal airway structure models were calculated from computed tomography data of 128 Chinese Han nationality using statistical shape model. The deposition evaluation devices were further designed, and an imaging method was then employed to obtain drug deposition information. Furthermore, drug spatial deposition atlases were proposed by UV unwrapping, a mathematical mapping procedure flattening three-dimensional (3D) information to two-dimension bidirectionally, to achieve quantification of drug deposition fractions in the regions of interest. Moreover, the feasibility and universality of this method were verified by correlating it with the chemical quantitative results and computational fluid dynamic simulation of drug deposition of mometasone furoate nasal spray and hydroxypropyl methylcellulose nasal powder, respectively. Finally, the unique drug spatial deposition atlases of these two formulations in the male and female evaluation devices were generated, respectively. In summary, the standard nasal airway structure models of the Chinese Han nationality and the drug spatial deposition atlases provide scientific tools for the formulation optimization and quality control of nasal formulations.