Three--dimensional medical imaging: Algorithms and computer systems

This paper presents an introduction to the field of three-dimensional medical imaging It presents medical imaging terms and concepts, summarizes the basic operations performed in three-dimensional medical imaging, and describes sample algorithms for accomplishing these operations. The paper contains a synopsis of the architectures and algorithms used in eight machines to render three-dimensional medical images, with particular emphasis paid to their distinctive contributions. It compares the performance of the machines along several dimensions, including image resolution, elapsed time to form an image, imaging algorithms used in the machine, and the degree of parallelism used in the architecture. The paper concludes with general trends for future developments in this field and references on three-dimensional medical imaging

The slicing extent technique for fast ray tracing

A new technique for image generation using ray tracing is introduced. The “Slicing Extent Technique” (SET) partitions object space with slicing planes perpendicular to all three axes. Planes are divided into two dimensional rectangular cells, which contain pointers to nearby objects. Cell size and the space between slices varies, and is determined by the objects’ locations and orientations. Unlike oct-tree and other space-partitioning methods, SET is not primarily concerned with dividing space into mutually exclusive volume elements (‘voxels’) and identifying objects within each voxel. Instead, SET is based on analysis of projections of objects onto slicing planes. In comparison to the existing space subdivision methods for ray tracing, SET avoids tree traversal and exhibit no anomalous behavior. There is no reorganization when new objects arrive. Preprocessing to create slices is inexpensive and produces a finely tuned filter mechanism which supports rapid ray tracing