Two Talks:
The Exploration of Cross-Sectional Data with a Virtual Endoscope
and
Marching Through the Visible Man
Bill Lorensen
GE Corporate R&D
Schenectady, NY
The Exploration of Cross-Sectional Data with a Virtual Endoscope
Endoscopes provide real-time, high resolution video views of the interior of hollow organs and cavities that exist within the human body. Although endoscopic examinations are mostly non-invasive, the procedures still require some sedation or anesthesia to reduce patient discomfort. X-Ray Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) are non-invasive diagnostic imaging techniques that display internal anatomy in cross sections called slices. For the most part, radiologists view the 2D cross sections and create mental images of the 3D structures present in the study. However, many of the tubular structures that exist in the body have complex morphology, passing back and forth through the cross sections. This talk illustrates techniques for the internal exploration of CT / MRI data that have been reconstructed into 3D surfaces. The views produced by the new methods simulate the types of views that can be obtained with endoscopes. Examples from the brain, cranium, chest, and abdomen illustrate the techniques.
Marching Through the Visible Man
The National Library of Medicine is creating a digital atlas of the human body. This project, called the Visible Human, has already produced computed tomography, magnetic resonance imaging and physical cross-sections of a human male cadaver. This talk describes a methodology and results for extracting surfaces from the Visible Male's CT data. We use surface connectivity and isosurface extraction techniques to create polygonal models of the skin, bone, muscle and bowels. Early experiments with the physical cross-sections are also reported.
Bill Lorensen is a Graphics Engineer in the Imaging and Visualization Laboratory at GE's Corporate Research and Development Center in Schenectady, NY. He has 25 years of experience in computer graphics and software engineering. Bill is currently working on algorithms for 3D medical graphics and scientific visualization. He is a co-inventor of the marching cubes and dividing cubes surface extraction algorithms that have become the defacto standard for isosurface extraction in the scientific visualization and medical imaging communities. Bill is one of the chief architects of LYMB, an object-oriented software development environment written in C. His other interests include computer animation, color graphics systems for data presentation, and object-oriented software tools. Bill is the author or co-author of over 60 technical articles on topics ranging from finite element pre/postprocessing, 3D medical imaging, computer animation and object-oriented design. He is a co-author of "Object Oriented Modeling and Design" published by Prentice Hall, 1991. He gives frequent tutorials at the annual SIGGRAPH and IEEE Visualization conferences.
Bill holds sixteen US Patents on medical and visualization algorithms. In 1991, he was named a Coolidge Fellow, the highest scientific honor at GE's Corporate R&D.
Prior to joining GE in 1978, he was a Mathematician at the US Army Benet Weapons Laboratory where he worked on computer graphics software for structural analysis. He has a BS in Mathematics and an MS in Computer Science from Rensselaer Polytechnic Institute.