[Principles and current possibilities of virtual scenarios for surgery planning].

This paper describes several new visualization and interaction techniques that enable the use of virtual environments for routine medical purposes. A new volume-rendering method supports shaded and transparent visualization of medical image sequences in real-time with an interactive threshold definition. Based on these rendering algorithms a segmentation approach offers intuitive assistance for a wide range of requirements in diagnosis and therapy planning. In addition, a hierarchical data representation for geometric surface descriptions guarantees optimal use of available hardware resources and prevents inaccurate visualization. Applications such as virtual endoscopy are described.