Abstract
BackgroundUnderstanding airflow through human airways is of importance in drug delivery and development of assisted breathing methods. In this work, we focus on development of a new method to obtain an averaged upper airway geometry from computed tomography (CT) scans of many individuals. This geometry can be used for air flow simulation. We examine the geometry resulting from a data set consisting of 26 airway scans. The methods used to achieve this include nasal cavity segmentation and a deformable template matching procedure.MethodsThe method uses CT scans of the nasal cavity of individuals to obtain a segmented mesh, and coronal cross-sections of this segmented mesh are taken. The cross-sections are processed to extract the nasal cavity, and then thinned (‘skeletonized’) representations of the airways are computed. A reference template is then deformed such that it lies on this thinned representation. The average of these deformations is used to obtain the average geometry. Our procedure tolerates a wider variety of nasal cavity geometries than earlier methods.ResultsTo assess the averaging method, key landmark points on each of the input scans as well as the output average geometry are located and compared with one another, showing good agreement. In addition, the cross-sectional area (CSA) profile of the nasal cavities of the input scans and average geometry are also computed, showing that the CSA of the average model falls within the variation of the population.ConclusionsThe use of a deformable template method for aligning and averaging the nasal cavity provides an improved, detailed geometry that is unavailable without using deformation.Electronic supplementary materialThe online version of this article (doi:10.1186/s12880-016-0154-8) contains supplementary material, which is available to authorized users.
Highlights
Understanding airflow through human airways is of importance in drug delivery and development of assisted breathing methods
Simulation of airflow through human upper airways is of importance in a number of medical applications, including the improvement of artificial respiratory devices [1] for conditions such as obstructive sleep apnea (OSA), and for delivery of drugs through aerosol deposition [2]
We show that the use of deformable registration allows better matching between nasal cavities, and results in an average geometry that includes finer details
Summary
Understanding airflow through human airways is of importance in drug delivery and development of assisted breathing methods. We focus on development of a new method to obtain an averaged upper airway geometry from computed tomography (CT) scans of many individuals. This geometry can be used for air flow simulation. Be applicable to cross-sections that are not single closed curves i.e. where congestion is present, making a single closed curve insufficient to represent the boundary of the cross-section (see Fig. 2) It is not known how well the Fourier descriptor method works with shapes that show significant variation
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
