Nava A, Mazza E, Furrer M, Villiger P, Reinhart W H
Department of Mechanical Engineering, Swiss Federal Institute of Technology, 8092 Zurich, Switzerland.
Med Image Anal. 2008 Apr;12(2):203-16. doi: 10.1016/j.media.2007.10.001. Epub 2007 Oct 23.
The mechanical behavior of human liver has been characterized with aspiration experiments. Measurements have been performed in vivo under sterile conditions during open surgery. Twenty-three measurements on six healthy human livers were performed using the same loading history for each test, so to allow a direct comparison of the measured deformations. The measurement results are reported and the experimental uncertainties evaluated. One of the main objectives of the present paper is to share information on the in vivo mechanical response of human liver with the biomechanics research community: the present data can be used for mechanical model development and validation purposes. The parameters of a quasi-linear viscoelastic model have been determined from the experimental data by means of inverse finite element calculations. The corresponding linear elastic modulus is compared with values from the literature. In particular, a significant discrepancy has been found with respect to the values proposed by Carter et al. [Carter, F.J., Frank, T.G., Davies, P.J., McLean, D., Cuschieri, A., 2001. Measurement and modelling of the compliance of human and porcine organs. Medical Image Analysis 5, 231-236] and the reasons for this difference are discussed. The predictive capabilities of the quasi-linear viscoelastic model and the Rubin Bodner non-linear elastic-viscoplastic model are compared with respect to the tissue response in repeated aspiration cycles. Finally, for demonstration purposes, the constitutive model corresponding to the "average" liver response has been implemented into a finite element whole liver model and used for simulations related to liver surgery.
人类肝脏的力学行为已通过抽吸实验进行了表征。测量是在开放手术期间的无菌条件下在体内进行的。对六个健康人类肝脏进行了23次测量，每次测试使用相同的加载历史，以便直接比较测量的变形。报告了测量结果并评估了实验不确定性。本文的主要目标之一是与生物力学研究界分享有关人类肝脏体内力学响应的信息：当前数据可用于机械模型的开发和验证目的。通过逆有限元计算从实验数据中确定了准线性粘弹性模型的参数。将相应的线性弹性模量与文献中的值进行了比较。特别是，发现与卡特等人提出的值存在显著差异。[卡特，F.J.，弗兰克，T.G.，戴维斯，P.J.，麦克林，D.，库奇耶里，A.，2001年。人类和猪器官顺应性的测量与建模。医学图像分析5，231 - 236]并讨论了这种差异的原因。比较了准线性粘弹性模型和鲁宾·博德纳非线性弹粘塑性模型在重复抽吸循环中对组织响应的预测能力。最后，为了演示目的，将对应于“平均”肝脏响应的本构模型应用于有限元全肝模型，并用于与肝脏手术相关的模拟。
