气流作用下气道组织变形的流固耦合研究  

FLUID–SOLID COUPLING STUDY OF AIRWAY TISSUE DEFORMATIONS UNDER AIRFLOW

作　　者：秦源 陈茜[2] 魏东 任晓勇[2] 徐光魁 Qin Yuan;Chen Xi;Wei Dong;Ren Xiaoyong;Xu Guangkui(Laboratory for Multiscale Mechanics and Medical Science,School of Aerospace Engineering,Xi’an Jiaotong University,Xi'an 710049,China;Department of Otorhinolaryngology Head and Neck Surgery,The Second Affiliated Hospital of Xi’an Jiaotong University,Xi’an 710004,China;State Key Laboratory of Aerodynamics,Mianyang 621000,Sichuan,China)

机构地区：[1]西安交通大学航天航空学院多尺度力学-医学交叉实验室,西安710049 [2]西安交通大学第二附属医院耳鼻咽喉头颈外科,西安710004 [3]空气动力学国家重点实验室,四川绵阳621000

出　　处：《力学学报》2024年第2期472-481,共10页Chinese Journal of Theoretical and Applied Mechanics

基　　金：国家自然科学基金资助项目(12072252,11972361)。

摘　　要：悬雍垂腭咽成形术(UPPP)是一种治疗阻塞性睡眠呼吸暂停(OSA)的常规外科手术,然而由于手术作用机制仍不清楚,手术成功率较低.现有的研究大多忽略了患者上气道的具体形态以及呼吸作用下气道软组织的弹性变形,不足以有效指导手术治疗.文章基于OSA患者在术前、术后的CT扫描图像,构建了精确的三维上气道模型,通过双向流固耦合(FSI)计算,模拟研究了呼吸作用下上气道软组织的弹性变形和气道内气流流动情况.比较手术成功案例和失败案例中OSA患者上气道的流速、压力分布及气道弹性变形情况,从气道流体流动状态和气道软组织变形的角度解释了OSA的发生原因与手术作用机制.结果表明,最小横截面积尺寸并不是UPPP手术成功与否的决定性因素,成功的手术应当是减轻气道壁负压力程度、降低气道进出口之间的压降.此外,使用双向FSI方法,文章进一步构建了简化的人体二维软腭模型,探究了软腭弹性模量对吸气过程的影响,发现当软腭的弹性模量在0.5~1.5 MPa的范围内时,刚度更小的软腭会改善流场的流动情况,但也更易发生变形塌陷.文章所发展的流固模型为个性化预测手术效果提供了研究工具.The uvulopalatopharyngoplasty(UPPP)is a common surgical procedure used to treat obstructive sleep apnea(OSA).However,due to the unclear mechanism of action,it is not possible to achieve the ideal success rate for the surgery.The current studies mostly overlook the specific morphology of the patient’s upper airway or the elastic deformation of the airway soft tissues,which results in the existing results not being sufficient to effectively guide surgical treatment.In this study,we constructed an accurate three-dimensional upper airway model based on CT scan images of OSA patients before and after surgery,and simulated and studied the elastic deformations of soft tissues in the upper airway through bi-directional fluid-structure interaction(FSI)calculation.We compared the flow velocity,pressure distribution,and elastic deformation of the upper airways in successful and failed cases of surgery for OSA,and explained the cause of OSA and the mechanism of surgery from the perspective of fluid flow in the airway and deformation of the airway soft tissues.Our results showed that the size of the minimum cross-sectional area is not the decisive factor for the success of UPPP surgery.Successful surgery can reduce the negative pressure level on the airway walls and decrease the pressure drop between the inlet and outlet of the airway.In addition,by using the bi-directional FSI method,we further simplified a two-dimensional soft palate model to investigate the influence of the soft palate’s elastic modulus on the inhalation process.It is found that a softer palate can improve the flow field’s flow state when the elastic modulus of the soft palate is within the range of 0.5 MPa to 1.5 MPa,yet it is also more prone to deform and collapse.The fluid-solid coupling model developed in this study provides a research tool for personalized prediction of surgical outcomes.

关 键 词：上气道 阻塞性睡眠呼吸暂停 双向流固耦合 压降 数值模拟 

分 类 号：O39[理学—工程力学]