用数字建模方法研究喉狭窄对吸气相气流特征的影响  

Impact of laryngeal stenosis on inspiratory airflow characteristics:a comparative study based on numerical simulation

作　　者：邓达 姜垂广 钱永 DENG Da;JIANG Chui-guang;QIAN Yong(Department of Head and Neck Surgery,Hainan Cancer Hospital,Haikou Hainan 570311,China)

机构地区：[1]海南省肿瘤医院头颈外科,海南海口570311

出　　处：《临床和实验医学杂志》2023年第3期292-296,共5页Journal of Clinical and Experimental Medicine

基　　金：海南省卫生计生行业科研项目(编号:16A200035)。

摘　　要：目的探讨狭窄喉腔的解剖形态改变对吸气相气流流场的影响。方法回顾性选取2019年8月至9月海南省肿瘤医院收治的1例成年男性的正常喉腔CT影像和1例成年男性喉癌患者(无吸气性呼吸困难症状)术前的颈部CT影像资料,分别用Mimics17.0软件建立气道三维模型,并用Fluent 19.1对该模型进行网格化处理,随后对用力吸气过程进行模拟,然后用CDF-Post 19.1软件对其气流流场进行分析、计算。从一份正常的肺功能报告图中截取一个用力呼吸周期图像,用Origin 2016软件对其肺容量-时间曲线进行点抓取,并拟合成函数曲线,再对该肺容量-时间函数进行求导,得出流量-时间函数曲线,以该流量-时间函数作为预设条件输入Fluent 19.1进行模拟运算。结果狭窄气道的横截面积变化率高于正常气道;正常气道内的气流流线形态基本保持层流状态,而狭窄气道内的气流流线形态在气流流量迏峰前便已形成湍流;狭窄气道内压强的时间变化率、空间变化率等均高于正常气道。结论在正常喉腔的“双漏斗”结构中,不同水平面的截面积存在着一定的“适配性”,可以保证吸气过程中气流的稳定性;而存在病变的喉腔,即使没有导致明显的喉阻塞症状,其正常结构发生改变、“适配性”也遭到破坏,因此在吸气过程中会形成湍流。Objective To study the impact of laryngeal stenosis on the inspiratory airflow within the airway.Methods The CT images of a patient with a normal airway and the pre-operative CT images of a patient with laryngeal carcinoma without any dyspnea admitted to Hainan Cancer Hospital from August to September 2019 were retrospectively selected,and three-dimensionally reconstructed with Mimics 17.0 and meshed for computational fluid dynamics(CFD)simulation with Fluent 19.1.The results were post-processed with CDF-Post 19.1 so that the aerodynamics could be compared between the normal and the stenosed airway models.The pulmonary function report in the form of pulmonary volume-time graph without any abnormality was selected from the past database.The graph of a forced respiration cycle was digitized and plotted with Origin 2016,which was then differentiated to obtain the flow rate-time function.The flow rate-time function was inputted into Fluent 19.1 to serve as one of the boundary conditions of the simulation.Results The changing rates of cross-sectional areas were larger in the stenosed airway than that in the normal airway.The streamlines in the normal airway almost aways kept laminar while they got turbulent in the stenosed airway even before the time of peak flow.The time-dependent and space-dependent changing rates of pressure values were both larger in the stenosed airway than in the normal airway.Conclusion The double-funnel shape of the normal larynx helped keep the inspiratory streamlines steady and laminar,for there could be some sort of adaptability amongst the cross sections at different horizons with different areas.In the case of the stenosed airway,the lesion did not only narrow the laryngeal lumen but also changed the adaptability aforementioned,causing turbulence during forced inspiration in spite that no dyspnea was complained by the patient himself.

关 键 词：气流动力学 计算流体力学 喉狭窄 

分 类 号：R739.65[医药卫生—肿瘤]