High-resolution imaging modalities, such as magnetic resonance imaging (MRI) and computer tomography (CT), combined with advances in computer technology, have prompted a renewed interest and have led to significant progress in the volumetric reconstruction of medical images. Assessment of such techniques for various clinical applications and medical educational interpretations are currently under investigation by many medical and scientific groups. The purpose of the paper is to highlight various clinical applications that show potential for the utilization of volumetric rendering of medical images. Such applications include (1) diagnostics, (2) preoperative planning, (3) intraoperative navigation, (4) surgical robotics, (5) postoperative validation, (6) training, and (7) telesurgery. First, however, the authors try to identify the sources of the patients' imaging data, outlining several popular segmentation and volumetric rendering techniques. At the conclusion, they discuss the necessary requirements to deploy a practical three-dimensional (3D) software for clinicians. The paper is intended for those who would like to obtain and general understanding of the clinical 3-D rendering process and its applications. No effort is made at detailing the various volumetric rendering, segmentation, or user interface design techniques, nor is any effort made to review the commercially available software. Although some sample publications are listed to illustrate the various mythologies, no attempt is made at providing a complete coverage of the literature.

In radiosurgery a beam of radiation is used as an ablative surgical instrument to destroy brain tumors. Treatment planning consists of computing a sequence of beam configurations for delivering a necrotic dose to the tumor, without damaging healthy tissue or particularly critical structures. In current systems, kinematic limitations severely constrain beam motion. This often results in inappropriate dose distributions. A new radiosurgical system has been implemented to overcome this disadvantage. In this system, a compact radiation source of high energy is moved by a 6-dof robotic arm. We describe algorithms for computing a motion with specified characteristics for this new system. Treatment plans used at test sites with earlier systems are compared to plans computed with the described algorithms. The experience reported shows that full kinematic flexibility combined with treatment planning algorithms allows for better protection of healthy tissue and higher dosage in tumors.>

In radiosurgery a moving beam of radiation is used as an ablative surgical instrument to destroy brain tumors. A new camera-guided system capable of tracking patient motion during treatment has been built. The radiation source is moved by a six degree-of-freedom robotic arm. In addition to offering a more cost effective, less invasive, and less painful treatment, the robotic gantry allows for arbitrary spatial motion of the radiation source. Based on this feature we can treat non-spherical lesions with accuracies unachievable with classical radiosurgical systems. The system introduces a new class of radiosurgical procedures, called non-stereotactic, or image-guided radiosurgery. At the heart of these procedures are algorithms for planning both a treatment and the corresponding beam motion, given the geometric description of the tumor shape and relative locations in the particular case.>