The NSF Japan Program/3D Visualization of Magnetic Resonance Images

DANIEL F. LEOTTA
Center for Bioengineering
University of Washington


Abstract

I was a participant in the 1995 Summer Institute in Japan, sponsored by the National Science Foundation and the Japanese government. This program is designed to expose US graduate students in engineering and science to Japanese research, language and culture. I was assigned to work in the clinical Magnetic Resonance Imaging section of the Department of Radiology at the University of Tsukuba. I assembled a software package for three-dimensional (3D) reconstruction and visualization of magnetic resonance (MR) images of the brain. Software was developed to convert images collected with a Philips MR machine in raw data format to a 3D data format which could be input to the visualization software package AVS (Advanced Visual Systems, Waltham, MA). A set of sequential parallel two-dimensional image slices could be converted to either AVS volume or AVS field format. These data formats are used by AVS to display the data as a 3D object. Within AVS, a number of visualization techniques were developed using the package’s network editing system. These networks accept 3D data sets and apply various visualization techniques to help analyze the data. The networks were documented by creating a set of examples from a 168-slice set of brain images. Visualization techniques included isosurface display, volume rendering, display of arbitrary slices, thresholding, and filtering. Color tables to highlight structures of interest (bone, tissue, fluid) were also created. As a final step, software was developed to save visualization views as images which could be exported to other graphics packages for archive or presentation.

Some examples of the 3D brain reconstructions can be found on my Japan page .