STUDY ON MECHANICAL CHARACTERIZATION OF LIVER TISSUE BASED ON HAPTIC DEVICES FOR VIRTUAL SURGICAL SIMULATION

摘要

In recent years, virtual surgical simulation has been one of the hot direction of digital medical research, it is mainly used in teaching, training, diagnosis, preoperative planning, rehabilitation and modeling and analysis of surgical instruments. The modeling of soft tissue of human organs is the basis to realize the virtual surgical simulation. The quasi-linear viscoelastic (QLV) theory has been proposed by Fung, and it was widely used for modeling the constitutive equation of soft tissues. The purpose of this study is to determine the mechanical characterization of the liver soft tissue based on the PHANTOM Omni Haptic devices. Five parameters are included in the constitutive equation with QLV theory, which must be determined experimentally. The specimens were obtained from fresh porcine liver tissues in vitro. The liver tissues were cut into 14mm×14mm×14mm cubes. Two types of unconfined compression tests were performed on cube liver specimens. Puncture tests were performed on the complete liver. The material parameters of the QLV constitutive equation were obtained by fitting the experimental data. These parameters will provide the references for the computational modeling of the liver in the virtual surgical simulation.