Guo Yufeng, Su Lijun, Cai Huikun, Gao Xingqiang, Wu Xiaohui, Xue Haoyang
Department of Otolaryngology Head and Neck Surgery，Xiamen Children's Hospital，Xiamen，361000，China.
School of Physics and Mechanical & Electrical Engineering，Xiamen University.
Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi. 2021 Feb;35(2):141-146. doi: 10.13201/j.issn.2096-7993.2021.02.011.
In this study, the characteristics of the upper airway flow field were analyzed by using computational fluid dynamics（CFD）. The study analyze the differences in the upper airway flow field between normal children and children with obstructive sleep apnea（OSA）, and the pathological characteristics of children with OSA were elaborated from the perspective of airway fluid dynamics. The upper airway models of a normal child and a child with OSA were constructed. The differences in the same inspiration pressure, such as airflow velocity, airflow pattern, ventilation volume, and pressure, were analyzed. To verify CFD results, rhinomanometry was carried out and an experimental bench based 3D technology was also built. The CFD results are consistent with the in vitro 3D model experiments and clinical measurement results. The adenoid area of nasopharynx is only 11.274 mm²of the child with OSA, about 1/6 of that of normal children. At the area of nasopharyngeal in OSA children, the flow velocity increased but the pressure dropped sharply, which was 69.197% of the total pressure drop, and the resistance value was 6.59 times of that of normal children. Streamline of nasopharyngeal is more disorder. Normal children's inspiratory flow was 116.139 mL/s, while OSA children's inspiratory flow was 47.055 mL/s, with a difference rate as high as 59.48%. The airflow of OSA children in nasopharynx is significantly different from that of normal children. The airflow characteristics of upper airway were discussed in detail with the use of CFD, which can help clinicians intuitively understand the abnormal flow behavior of children with OSA.
在本研究中，运用计算流体动力学（CFD）分析上气道流场的特征。该研究分析了正常儿童与阻塞性睡眠呼吸暂停（OSA）患儿上气道流场的差异，并从气道流体动力学角度阐述了OSA患儿的病理特征。构建了一名正常儿童和一名OSA患儿的上气道模型。分析了相同吸气压力下气流速度、气流模式、通气量和压力等方面的差异。为验证CFD结果，进行了鼻阻力测量，并搭建了基于3D技术的实验台。CFD结果与体外3D模型实验及临床测量结果一致。OSA患儿鼻咽部腺样体面积仅为11.274平方毫米，约为正常儿童的1/6。在OSA患儿鼻咽部区域，流速增加但压力急剧下降，占总压力降的69.197%，阻力值是正常儿童的6.59倍。鼻咽部流线更紊乱。正常儿童吸气流量为116.139毫升/秒，而OSA患儿吸气流量为47.055毫升/秒，差异率高达59.48%。OSA患儿鼻咽部气流与正常儿童有显著差异。利用CFD详细讨论了上气道的气流特征，这有助于临床医生直观了解OSA患儿的异常气流行为。
