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arXiv · 2108.04679

Inhalation and deposition of spherical and pollen particles after middle turbinate resection in a human nasal cavity

Abstract

Middle turbinate resection significantly alters the anatomy and redistributes the inhaled air. The superior half of the main nasal cavity is opened up, increasing accessibility to the region. This is expected to increase inhalation dosimetry to the region during exposure to airborne particles. This study investigated the influence of middle turbinate resection on the deposition of inhaled pollutants that cover spherical and non-spherical particles (e.g. pollen). A computational model of the nasal cavity from CT scans, and its corresponding post-operative model with virtual surgery performed was created. Two constant flow rates of 5_L/min, and 15_L/min were simulated under a laminar flow field. Inhaled particles including pollen (non-spherical), and a spherical particle with reference density of 1000 kg/m3 were introduced in the surrounding atmosphere. The effect of surgery was most prominent in the less patent cavity side, since the change in anatomy was proportionally greater relative to the original airway space. The left cavity produced an increase in particle deposition at a flow rate of 15_L/min. The main particle deposition mechanisms were inertial impaction, and to a lesser degree gravitational sedimentation. The results are expected to provide insight into inhalation efficiency of different aerosol types, and the likelihood of deposition in different nasal cavity surfaces.

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Kiao Inthavong, Yidan Shang, John M. Del Gaudio, Sarah K. Wise, Thomas S. Edwards, Kimberley Bradshaw, Eugene Wong, Murray Smith, Narinder Singh. 2021-08-09. Inhalation and deposition of spherical and pollen particles after middle turbinate resection in a human nasal cavity. https://doi.org/10.1016/j.resp.2021.103769

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