Tool could teach radiologists volumes

A software tool developed by German researchers allows the viewer to use a movable probe over a volume CT or MR image to designate a tissue slice from any angle, operating much like an ultrasound probe of live tissue. A refinement shown at the RSNA meeting permits the viewer to capture and mark the process they follow in moving the probe.

A software tool that allows a probe-based exploration of CT and MR volume data sets could become a learning tool for radiologists who are beginning to interpret 3D images, according to its developers.

Shown in an infoRAD exhibit, the tool is the latest incarnation of a concept introduced at the 2001 RSNA meeting. It allows a wand to be moved over a volume image to designate a tissue slice from any angle, operating much like an ultrasound probe of live tissue. The exhibit won awards in 2001 and 2002.

Since then, the developers have continued to refine the concept and add features. The latest addition is a tracking system that allows the user to capture the process of the wand as the viewer moves it through the data set. The user can also leave markers.

The product could be used as a learning tool to help radiologists learn volumetric interpretation strategies, said Michael Teistler, a professor of radiology at Braunschweig University of the Technology Institute for Medical Informatics in Germany. It could also be used in presentations.

Volume imaging is growing in importance as MR sequences and multidetector scanners generate more images per study. Radiologists are increasingly turning to volume image interpretation strategies to overcome data overloads.

One problem, however, is that there are no real standards for dealing with volume imaging, Teistler said. Although the imaging and software tool does not provide the standards, it does contribute to an understanding of how they might be developed as volume imaging moves into clinical practice.

The basic volume imaging tool has been a big draw at the RSNA infoRAD exhibit. It won a magna cum laude award in 2001 and a cum laude award in 2002. The first version was primarily educational and based on the Visible Human Project, Teistler said. The second version showed the diagnostic possibilities, and this year's version improves on that concept.

Although it is based on CT and MR data sets, the visualization tool could be adapted to 3D ultrasound data sets, he said. A video showing the system is available at www.virtusmed.com/demo.mpg.