When Dr. James R. Wong, chairman of Radiology and Oncology at Morristown Memorial Hospital, sold the engineers at Siemens Oncology Care Systems (Concord, CA) on his concept of connecting a computerized tomography (CT) scanner and linear accelerator, Siemens ran with it and developed a system called Primatom. The image-guided radiation therapy system delivers therapeutic radiation to prostate tumors more accurately than other techniques. With the coupled equipment, the scanner moves down the patient instead of the patient and his table moving through the scanner. The patient (and tumor) remain immobile, and the chances of over-radiating healthy tissue go down. Because new scans can be done before each treatment, the therapist always knows the exact spot to target.
The imaging equipment scans a body or object in a series of "slices," each of which shows the interior of the subject at that exact spot. At this stage in the development of Primatom technology, although the results of the CT scan appear on an attached computer monitor, Wong prints out the scan and compares it to one done before the start of treatment. "In the future this will be done with image merging on the computer screen," he says.
A company in Germany, Volume Graphics GmbH, may have an even better way for Wong to view scans on his computer—using a software system that turns CT scans into high resolution, fully textured, three dimensional images.
Automotive and electronics manufacturers also use Volume Rendering software from Volume Graphics. The program helps manufacturers to see all the interior volumetric information of prototypes, parts, and products, along with any weak or faulty areas, as well as—going back to the original reason for CT development—the human body. Already proving popular in Europe with such automobile companies as BMW and Daimler-Chrysler, and with cell phone and other electronics manufacturers, the system can reduce the number of prototypes that have to be tested.
Volume Rendering converts the scans into voxel (volumetric) data for visualization and data analysis—creating a high resolution, textured, three-dimensional image by using very fast volume ray-tracers and renderers and several different graphics cards in an OpenGL format that enables polygon/volume mixing to create 3D images. Volume Rendering users move through the object dynamically, just as the scanner did, so they can segment the object, measure volume, surface, distance, and angle, and perform statistical analysis.
Volume Rendering reads in each slice at a resolution of 1,000 pixels by 1,000 pixels. Sometimes this can result in very large files. "It's possible to analyze and process up to a gigabyte of voxel data on a PC, and new platforms such as the 64-bit Itanium processor let engineers work with 16 GB files—as happened when Daimler-Chrysler scanned a part that was 2,000 pixels by 2,000 pixels by 2,000 pixels, at two bytes per pixel," says Christof Reinhart, managing director of Volume Graphics.
"Although scanners are costly, industries such as automotive and aerospace already use them to check parts. Smaller companies can buy used equipment, and some manufacturers make scanners specifically for industry," he says.
Volume Rendering is also in use for healthcare in Europe—completing the circle of engineering and medicine.
For more information about Volume Rendering from Volume Graphics GmbH: Enter 533