Institute of Technical Medicine (ITeM), Furtwangen University, 78054, Villingen-Schwenningen, Germany.
Department of Microsystems Engineering, IMTEK, University of Freiburg, 79110, Freiburg, Germany.
Biomech Model Mechanobiol. 2023 Dec;22(6):2033-2061. doi: 10.1007/s10237-023-01749-8. Epub 2023 Aug 13.
Aiming for sensing balloon catheters which are able to provide intraoperative information of the vessel stiffness and shape, the present study uses finite element analysis (FEA) to evaluate the interaction between high-compliant elastomer balloon catheters with the inner wall of a non-cylindrical-shaped lumen structure. The contact simulations are based on 3D models with varying balloon thicknesses and varying tissue geometries to analyse the resulting balloon and tissue deformation as well as the inflation pressure dependent contact area. The wrinkled tissue structure is modelled by utilizing a two-layer fibre-based Holzapfel-Gasser-Ogden constitutive model and the model parameters are adapted based on available biomechanical data for human urethral vessel samples. The balloon catheter structure is implemented as a high-compliant hyper-elastic silicone material (based on polydimethylsiloxane (PDMS)) with a varying catheter wall thickness between 0.5 and 2.5 µm. Two control parameters are introduced to describe the balloon shape adaption in reaction to a wrinkled vessel wall during the inflation process. Basic semi-quantitative relations are revealed depending on the evolving balloon deformation and contact surface. Based on these relations some general design guidelines for balloon-based sensor catheters are presented. The results of the conducted in-silico study reveal some general interdependencies with respect to the compliance ratio between balloon and tissue and also in respect of the tissue aspect ratio. Further they support the proposed concept of high-compliant balloon catheters equipped for tactile sensing as diagnosis approach in urology and angioplasty.
为了研发能够提供术中血管硬度和形状信息的感应球囊导管，本研究使用有限元分析（FEA）来评估高顺应性弹性体球囊导管与非圆柱状管腔结构内壁之间的相互作用。接触模拟基于具有不同球囊厚度和不同组织几何形状的 3D 模型，以分析由此产生的球囊和组织变形以及充气压力相关的接触面积。通过利用两层基于纤维的 Holzapfel-Gasser-Ogden 本构模型来模拟皱缩的组织结构，并且根据人类尿道血管样本的可用生物力学数据来调整模型参数。球囊导管结构被实现为具有高顺应性的超弹性硅酮材料（基于聚二甲基硅氧烷（PDMS）），导管壁厚度在 0.5 和 2.5 µm 之间变化。引入了两个控制参数来描述在充气过程中球囊对皱缩血管壁的形状适应。基于不断演变的球囊变形和接触表面，揭示了一些基本的半定量关系。基于这些关系，提出了一些用于基于球囊的传感器导管的一般设计准则。所进行的计算机研究的结果揭示了一些关于球囊与组织之间顺应性比以及组织纵横比的一般相关性。此外，它们支持了配备触觉传感器的高顺应性球囊导管作为泌尿科和血管成形术诊断方法的概念。
