Shrink-wrapped isosurface from cross sectional images.

This paper addresses a new surface reconstruction scheme for approximating the isosurface from a set of tomographic cross sectional images. Differently from the novel Marching Cubes (MC) algorithm, our method does not extract the iso-density surface (isosurface) directly from the voxel data but calculates the iso-density point (isopoint) first. After building a coarse initial mesh approximating the ideal isosurface by the cell-boundary representation, it metamorphoses the mesh into the final isosurface by a relaxation scheme, called shrink-wrapping process. Compared with the MC algorithm, our method is robust and does not make any cracks on surface. Furthermore, since it is possible to utilize lots of additional isopoints during the surface reconstruction process by extending the adjacency definition, theoretically the resulting surface can be better in quality than the MC algorithm. According to experiments, it is proved to be very robust and efficient for isosurface reconstruction from cross sectional images.

Virtual cutting of anatomical structures.

In the context of medicine cutting is one of the most important operations. Many surgical tasks start with an incision, allowing the surgeon to access the region of interest, using either conventional or minimal invasive surgery techniques. The work presented herein should be seen in the context of surgical training and preoperative planning using computer assisted medical simulation systems. The main result of this work is the proposed cutting algorithm based on predefined templates. To integrate this approach in the existing surgical training simulator and to handle additional tasks like soft tissue deformation, needed by the medical environment, a generic simulation framework was developed. This framework is able to utilize given multiprocessor- and network-environments to achieve the desired realtime interactivity.

Training environment for inferior vena caval filter placement.

This paper describes a Virtual Environment system designed to aid in training interventional radiologists in inferior vena cava filter placement. It is being developed as part of a VE simulator for a number of surgical and interventional radiology procedures at the Laboratory for Advanced Computer Applications in Medicine at the George Washington University. In this procedure a filter is placed in the inferior vena cava to prevent blood clots from the lower portion of the body from reaching the lungs and causing a pulmonary embolus. The simulation is designed to provide both tutorial and testing modes for the filter placement procedure.