| The 3D theater already has proven useful for examining cardiovascular and neurological systems and in studying and measuring fetuses. New Software Creates Interactive 3D Medical Imaging With visuals that clinicians and researchers can not only view head-on, but actually walk around and through, researchers in The Netherlands say they’ve realized the dream of truly interactive 3D medical imaging. “There are so many applications,” said Peter van der Spek, Ph.D., who led the development of the I-Space virtual reality theater at Erasmus University Medical Center in Rotterdam. “The first step is just realizing what you can do with it.” Envisioning how the technology can be used not only for research but also in diagnosis and treatment decisions, a company spawned by the project, Crosslinks, is working to develop and market the invention elsewhere in Europe and around the world. Historically, viewing a 3D image really meant looking at the image on a two-dimensional screen and then rotating or zooming in on the image to “see” around the scanned object. I-Space, powered by 3D volume rendering software that digests massive amounts of image data, uses eight projectors on four walls and the floor to create a 3D image in a special viewing arena. Users can then interact with the image, seeing its depth by wearing special glasses with polarizing lenses. Gene Mapping Project Was Model With a background in molecular genetic research and engineering, Dr. van der Spek, professor and head of the Department of Bioinformatics at Erasmus, was uniquely suited to bridge the gulf between 3D-rendering software and its medical and research applications. Returning to Erasmus—where he previously had trained—a few years ago after working with pharmaceutical companies on the human genome mapping project, Dr. van der Spek recognized that the same virtual reality software and technology used to map genes could have broader cross-disciplinary applications. Within 3 years he and his team had made Erasmus the first medical center in the world with its own 3D imaging theater. I-Space takes data from MR imaging, CT and ultrasonography and renders images for projection in three and four dimensions. The images can also be “played” back with a time component that allows researchers and physicians to see real-time animation, enabling analysis of elements such as irregular heartbeats or the movement of muscles. Multidisciplinary Uses Encouraged Dr. van der Spek joined Ronald Nanninga, M.Sc., to found Crosslinks, a company that aims to help medical personnel tackle large datasets with I-Space and other advanced visual information software. The pair said they have reason to be excited about I-Space’s potential. As Dr. van der Spek was helping develop the system over the past few years, he was also priming other departments and disciplines to take advantage when it was ready to launch. As a result, the theater already has proven useful for examining cardiovascular and neurological systems and in the study and measurement of fetuses. Child development researchers, in fact, inspired an important addition to the system. Clinicians studying early pregnancy wanted an imaging system that would give them precise 3D measurements of developing embryos and, with some software improvements, I-Space can now provide those measurements using ultrasound scans. The system also allows enormous enlargement of images for very detailed measurements, said Dr. van der Spek, and the measurements can be compiled into a “medical-pedia” used to screen for early indicators of abnormal developments. The 3D imaging in I-Space can also be applied to microscopic images, wherein the rendering of a large stack of cell images can help researchers find biomarkers for applications such as in cancer, cardiovascular and other disease areas. While the I-Space system is still too costly to apply to every individual diagnostic case, said Dr. van der Spek, clinicians could use a 3D room to convene a multidisciplinary team and determine the best interventional approach in complex cases. Moreover, he added, the system can also be used to train clinicians to use both 3D and 2D imagery. Medical professionals who have trouble understanding 3D elements within a two-dimensional image, he said, can use I-Space to work with true 3D images and improve their decision-making skills even when working with 2D scans. Financial and Logistical Barriers Must Be Overcome With the ambition of becoming a significant specialized player in the medical imaging market in the next 3 years, and partnerships formed with companies such as Silicon Graphics Inc. and Barco to aid in marketing, delivering, installing and supporting the hardware, Dr. van der Spek, Nanninga and others at Crosslinks acknowledge that I-Space theaters likely won’t be popping up around the world right away. Acquiring an I-Space system requires substantial financial, logistical and structural commitments from a site, they said. “At the moment we are talking with several medical centers in Europe to see how we can help them improve their research, diagnostic and educational capacities,” Nanninga said. What proved critical during the development of I-Space—and may well be important for its proliferation—is a cooperative multidisciplinary environment, said Dr. van der Spek. “Information technology can be very difficult and inaccessible to clinicians because they’re not trained in it,” he said. Using the complex technology effectively, he said, “depends very much on the culture within the institution and to what extent different groups work together.” He said he found that his engineering and medical background helped him cross disciplinary borders. Among the possibilities Dr. van der Spek visualizes for I-Space is the installation of 3D theaters near, if not actually within, operating rooms. Dynamic 3D scanning and rendering offered by the theater, he said, would help surgeons instantly see and adjust to the needs of their patients. The full text of an article explaining one application of I-Space, “Dynamic 3D Echocardiography in Virtual Reality” published in Cardiovascular Ultrasound, is available at www.pubmedcentral.gov/articlerender.fcgi?artid=1343588. 
Ronald Nanninga, M.Sc. Crosslinks
Peter van der Spek, Ph.D.
Erasmus University Medical Center
I-Space uses 3D volume rendering software and eight projectors on four walls and the floor to create a 3D image in a special viewing arena. Users can then interact with the image. (left) Gracia Mancini, M.D., Ph.D., examines the MR image of a newborn with a malformation in cerebral cortex and cerebellum development. (right) Anton Koning, Ph.D., inspects an MR image dataset showing the abnormally large ventricles of a patient with a migration disorder.
3D Imaging at RSNA 2006 Special focus sessions and refresher courses at RSNA 2006 will address 3D imaging. Special focus sessions do not require registration. To register for these refresher courses, or any other courses, go to rsna2006.rsna.org and click on Registration, Housing & Courses. Special Focus Sessions: Virtual Colonoscopy: 2D, 3D, CAD or Gad—What’s Best? and Creating 3D Images: Clinicians or Technologists? RC430
Image Processing and 3D Imaging (Advanced Imaging Informatics) RC 432
Update Course in Diagnostic Radiology Physics: Multidimensional Image Processing, Analysis, and Display—Computer-aided Diagnosis in Breast Imaging * Clinical Applications of Image Analysis and Visualization for 3D Breast Imaging * Computer-supported Analysis of Breast MR Imaging in 4D: Why, When, and How? * Two-dimensional and 3D Multimodality CAD for Breast Cancer Diagnosis | 
