Interactive volume manipulation for supporting preoperative planning.

This paper presents a volume manipulation framework by which surgeons can interactively manipulate soft models like through surgical tools. The framework robustly simulates common surgical manipulations such as grasping, holding, cutting and retraction. We simulate cutting based on FEM formulation by replacing vertices and eliminating elements, without subdividing elements or adding new vertices. The size of stiffness matrix is constant. We also present real-time volume shading methods for deformable modeling. Our algorithms achieved interactive response in volume manipulation. Several surgical approaches and procedures were rehearsed and used for preoperative discussion.