Hazeri Mohammad, Faramarzi Mohammad, Sadrizadeh Sasan, Ahmadi Goodarz, Abouali Omid
School of Mechanical Engineering, Shiraz University, Shiraz, Iran.
Department of Otolaryngology-Head & Neck Surgery, Shiraz University of Medical Sciences, Shiraz, Iran.
J Aerosol Sci. 2021 Feb;152:105700. doi: 10.1016/j.jaerosci.2020.105700. Epub 2020 Oct 19.
The nasal cavity is the inlet to the human respiratory system and is responsible for the olfactory sensation, filtering pollutant particulate matter, and humidifying the air. Many research studies have been performed to numerically predict allergens, contaminants, and/or drug particle deposition in the human nasal cavity; however, the majority of these investigations studied only one or a small number of nasal passages. In the present study, a series of Computed Tomography (CT) scan images of the nasal cavities from ten healthy subjects were collected and used to reconstruct accurate 3D models. All models were divided into twelve anatomical regions in order to study the transport and deposition features of different regions of the nasal cavity with specific functions. The flow field and micro-particle transport equations were solved, and the total and regional particle deposition fractions were evaluated for the rest and low activity breathing conditions. The results show that there are large variations among different subjects. The standard deviation of the total deposition fraction in the nasal cavities was the highest for <impaction parameter (IP)< with a maximum of 20%. The achieved results highlighted the nasal cavity sections that are more involved in the particle deposition. Particles with IP = 30,000 deposit more in the middle turbinate and nasopharynx areas, while for particles with IP = 300,000, deposition is mainly in the anterior parts (kiesselbach and vestibule regions). For small IP values, the amounts of deposition fractions in different regions of the nasal cavity are more uniform.
鼻腔是人体呼吸系统的入口，负责嗅觉、过滤污染物颗粒物以及湿润空气。已经进行了许多研究以数值预测过敏原、污染物和/或药物颗粒在人体鼻腔中的沉积；然而，这些研究大多只研究了一个或少数几个鼻道。在本研究中，收集了十名健康受试者鼻腔的一系列计算机断层扫描（CT）图像，并用于重建精确的三维模型。为了研究鼻腔不同具有特定功能区域的传输和沉积特征，所有模型被划分为十二个解剖区域。求解了流场和微粒传输方程，并评估了静息和低活动呼吸条件下的总颗粒沉积分数和区域颗粒沉积分数。结果表明，不同受试者之间存在很大差异。鼻腔中总沉积分数的标准偏差在<撞击参数（IP）<时最高，最大值为20%。所获得的结果突出了鼻腔中更多参与颗粒沉积的部分。IP = 30000的颗粒在中鼻甲和鼻咽区域沉积更多，而对于IP = 300000的颗粒，沉积主要在前部（克氏区和前庭区域）。对于较小的IP值，鼻腔不同区域的沉积分数更为均匀。
