Realistic visualization for surgery simulation using dynamic volume texture mapping and model deformation

Realistic visualization is one of the key components for effective computer-assisted surgery simulations. Objects in the simulated environment should always provide correct visual appearance. In addition to properly changing the model geometry or topology in response to externally applied forces, such as cutting and dragging actions, the correct object appearance must be displayed after the geometry or topology is modified. Geometric surface representations of objects provide a direct and intuitive form for use in simulation systems, and they are relatively easy to implement. The disadvantage of geometric surface representation is that the interior content of the object is missing. When object cutting is performed that alters the object topology involving this interior, the correct appearance cannot be provided. Volumetric data representations retain objects in the volume element format and have the advantage of preserving volume content. A potential disadvantage of manipulating such volumes is reduced speed and flexibility. This paper describes an approach which combines geometric and volumetric representations to provide a real-time and realistic interactive surgery simulation system. This system uses geometric representation for efficiency and volume content for appearance. Physics-based object deformation and 3-D texture mapping provide an effective means of interactive volume visualization for realistic data-specific surgery simulation.