Interactive 3-dimensional segmentation of MRI data in personal computer environment

We describe a method of interactive three-dimensional segmentation and visu alization for anatomical magnetic resonance imaging (MRI) data in a persona l computer environment. The visual feedback necessary during 3-D segmentati on was provided by a ray casting algorithm, which was designed to allow use rs to interactively decide the visualization quality depending on the task- requirement. Structures such as gray matter, white matter, and facial skin from Tl-weighted high-resolution MRI data were segmented and later visualiz ed with surface rendering. Personal computers with central processing unit (CPU) speeds of 266, 400, and 700 MHz, were used for the implementation. Th e 3-D visualization upon each execution of the segmentation operation was a chieved in the order of 2 s with a 700 MHz CPU. Our results suggest that 3- D volume segmentation with semi real-time visual feedback could be effectiv ely implemented in a PC environment without the need for dedicated graphics processing hardware. (C) 2001 Elsevier Science B.V. All rights reserved.