The development of the graphics hardware in the last few years made them much faster. This brings new possibilities for complex visualizations in real-time. One application where a real-time visualization is very important is the interventional imaging for minimal-invasive surgeries. Thereby the physician has to do the surgery based on the provided visualization. In this book a new, complex technique is described which improves this visualization by integrating the pre-operative data, such as CT, directly in the final visualization together with the image from the interventional imaging...