An improved scheme of an interactive finite element model for 3D soft-tissue cutting and deformation

摘要

As a safe and feasible alternative to enriching and enhancing traditional surgical training, virtual-reality-based surgical simulators have been investigated for a long time. But it is still a challenge for researchers to accurately depict the behavior of human tissue without losing the flexibility of simulation. In this paper, we propose an improved scheme of an interactive finite element model for simulating the surgical process of organ deformation, cutting, dragging, and poking, which can maximally compromise the flexibility and reality of soft-tissue models. The scheme is based on our hybrid condensed finite element model for surgical simulation, which consists of the operational region and nonopera-tional region. Different optimizing methods applied to these regions make a contribution to the speedup of the calculation. Considering in a real surgical operation, dragging or poking operations are also necessary for surgeons to examine surrounding tissues of the pathological focus. The calculation within the area newly applied with forces in the nonoperational region is handled in our new scheme. The algorithm is modified accordingly in order to cope with this aspect. The design and implementation of the approach are presented. Finally, we provide two models to test our scheme. The results are analyzed and discussed to show the efficiency of our scheme.