基于数字化人体中耳-咽鼓管通气的数值仿真建模

Numerical simulation modeling of middle ear-eustachian tube ventilation based on Chinese digital visual human body

目的:基于中国数字化可视人体数据集建立中耳-咽鼓管三维模型,并通过计算机数值仿真来模拟咽鼓管开放后整个中耳-咽鼓管系统的形变和压力变化过程。方法:采用中国首例女性数字化可视人体数据集,使用Amira图像处理软件导入图像,Geomagic软件对图像进行分割等处理,形成包括咽鼓管、中耳鼓室、乳突气房、鼓膜、听小骨在内的中耳-咽鼓管三维模型。将三维模型导入Hypermesh软件中进行网格划分和分析。采用Abaqus软件进行结构力学计算,Xflow流体力学软件对气体流动进行数值仿真,利用流固耦合算法对咽鼓管开放时的组织变形和中耳压力变化进行数值模拟。在中耳-咽鼓管模型内设置包括鼓室、乳突、鼓峡、外耳道在内的多个压力监测点,记录并比较各监测点的压力变化。结果:本研究建立了包含咽鼓管、中耳鼓室、乳突气房、鼓膜、听小骨在内的中耳-咽鼓管三维模型和及中耳通气的数值仿真模型。通气后模型的动态变化可依据压力分5个阶段。此外,模型中鼓室、鼓峡监测点的压力变化基本同步;乳突气房的压力变化较鼓室、鼓峡延迟,验证了乳突的压力缓冲作用。并通过提取的外耳道压力曲线在数值、趋势上与咽鼓管测压检查基本一致,验证了模型的有效性。结论:本文建立的中耳-咽鼓管通气的数值仿真模型可模拟咽鼓管开放后的组织变形及中耳压力变化过程,具有较好的准确性和有效性。为中耳通气系统的研究提供了一种新的研究手段。

Objective To establish a three-dimensional model of middle ear-eustachian tube based on Chinese digital visual human dataset,and the deformation and pressure changes of the middle ear-eustachian tube system after eustachian tube opening are simulated by computer numerical simulation.Methods The first female Chinese Digital Visual Human data was adopted.The images were imported by Amira image processing software,and the images were segmented by Geomagic software to form a three-dimensional model of middle ear-eustachian tube system,including eustachian tube,tympanum,tympanic membrane,auditory ossicles,and mastoid air cells system.The 3D model was imported into Hypermesh software for meshing and analysis.The structural mechanics calculation was carried out by Abaqus,and gas flow was simulated by Xflow.The tissue deformation and middle ear pressure changes during eustachian tube opening were numerically simulated by fluid-solid coupling algorithm.Several pressure monitoring points including tympanum,mastoid,tympanic isthmus,and external auditory canal were set up in the model,and the pressure changes of each monitoring point were recorded and compared.Results In this study,a three-dimensional model of middle ear-eustachian tube and a numerical simulation model of middle ear ventilation were established,including eustachian tube,tympanum,mastoid air cells,tympanic membrane,and auditory ossicles.The dynamic changes of the model after ventilation could be divided into five stages according to the pressure.In addition,the pressure changes of tympanum and tympanic isthmus were basically synchronous,and the pressure changes of mastoid air cells system were later than that of tympanum and tympanic isthmus,which verified the pressure buffering effect of mastoid.The extracted pressure curve of the external auditory canal was basically consistent with that of tympanometry in terms of value and trend,which verified the effectiveness of the model.Conclusions The numerical simulation model of middle ear-eustachian tube ventilation established in this paper can simulate the tissue deformation and middle ear pressure changes after eustachian tube opening,and its accuracy and effectiveness are also verified.This not only lays a foundation for further research,but also provides a new research method for the study of middle ear ventilation.