具有详细解剖学结构的1岁学步儿童头部有限元模型构建及验证

Development and validation for finite element model of one-year-old toddler head with detailed anatomical structures

目的构建详细的1岁学步儿童头部有限元模型,探究其颅脑损伤机制,完善人体有限元生物力学模型数据库。方法基于我国1岁儿童真实详细的头部CT数据,借助医学软件Mimics获得头部几何结构数据,利用逆向工程软件划分NURBS曲面片和构建工程模型,利用有限元前处理软件划分网格,参照解剖学和尸体实验等数据,验证1岁学步儿童头部有限元模型的有效性并初步分析其损伤机制。结果构建了中国男性1岁儿童头部有限元模型,模型包括并区分了大脑及小脑的灰质和白质、海马体、囟门、矢状骨缝、冠状骨缝、脑干、脑室等,几何尺寸符合解剖学统计数据。利用头部模型重构了儿童头部静态压缩尸体实验和跌落尸体实验,结果表明,该头部模型与尸体实验表现了相近的力学特征,验证了模型的有效性。计算表明不同压缩速率下颅骨刚度不同,会导致不同损伤结果。结论所构建的包含详细解剖学结构的1岁儿童头部有限元模型具有较高的生物仿真度,借助构建的模型可分析深部脑组织各部位的详细损伤情况,特别是闭合性颅脑损伤,为相关研究及临床应用提供有效的工具和手段。

Objective To explore the brain injury mechanism and enrich the database of human finite element（FE） biomechanical model by developing the FE model of one-year-old toddler head.Methods Based on CT data from Chinese one-year-old toddler head with substantial and detailed information,the head model with detailed anatomical structure was constructed by using the medical software Mimics to get the head geometry data,as well as the reverse engineering software to divide NURBS surface and build the geometric model.Finally,the FE pre-processing software was used mesh the model.The FE model of one-year-old toddle head was validated by data from anatomic and cadaver experiments,and was used for preliminary analysis on damage mechanism of one-year-old toddler head.Results The FE model of Chinese one-year-old male toddler head was developed,which included and distinguished the gray matter and white matter of brain and cerebellum,hippocampus,fontanel,sagittal suture,coronal suture,brainstem and ventricles.The cadaver head static compression experiments and drop experiments were reconstructed by using this head model,and the results showed that the FE model of head had similar mechanical properties with the cadaver,which proved the validity of the FE model.Simulation results showed that skull stiffness and skull injury severity varied with different compression rates.Conclusions The FE model of one-year-old toddler head with detailed anatomical structures is of great biofidelity.The FE head model can be used to further investigate the detailed injury mechanism of deep brain tissues,especially for the closed craniocerebral injury,which provides an effective way and tool for the related research and clinical application.