High-tech suite of the future integrates imaging, robotics

Researchers in the field of interventional radiology have looked relentlessly for new ways to improve the accuracy, outcomes, and cost of their image-guided treatments. They have experimented with various tracking and navigational devices as well as robotics. Until now, these technologies have remained outside the realm of clinical practice. But the piling up of credible clinical data plus the collaborative efforts of academia, industry, and government could turn the IR suite of the future into an everyday reality in less than a decade.

That was the main message behind one of the most intriguing sessions featured at the 2008 Society of Interventional Radiology meeting in Washington, DC. The symposium, titled "Frontiers of Image Guided Interventional Oncology: Research and Development Strategies for the Future," brought together IR researchers, engineers, clinicians, manufacturers, and representatives of governmental agencies.

"Engineers, clinicians, industry, academics, and regulatory bodies often speak different languages and have their own agendas," said moderator and investigator Dr. Bradford Wood, chief of the interventional radiology lab at the National Institutes of Health's clinical center in Bethesda, MD. "When people find common ground, bridge communications, and speak the same language, amazing things happen."

According to Wood, that approach could help this aspect of interventional radiology move along faster by implementing a rational design rather than simply following market forces or patient demands. It would also help IRs prepare to incorporate these technologies, many of which are already commercially available, into their routine practice within the next five years or so, as credible clinical data on their application are published.

Most of these technologies were developed as aids for interventional oncology. Once IRs get their hands on any of these tools, however, they can be used in other patient populations and for different clinical applications, Wood said.

So far, the latest clinical trials in humans have focused on tracking and navigation to guide thermal ablation of the liver, lungs, kidneys, and prostate. Other potential applications include tracking and monitoring of "smart" guidewires and catheters during intravascular procedures and the guidance and placement of trocars and needles used in vertebroplasty.

The technologies in most cases combine electromagnetic devices that guide radiofrequency, high-intensity focused ultrasound or microwave ablation probes with registration or fusion of multiple imaging modalities. A number of researchers also are applying robotics to increase the accuracy and speed of these procedures.

The technology helps interventionalists, for instance, determine the exact location of an RFA needle in real-time using a multimodality data set that blends preprocedural anatomic, functional, and metabolic information. In a typical case, a patient may have a PET-positive liver tumor that does not show up on CT or MRI. The tumor can be partially seen on intraprocedural ultrasound, but the image may be suboptimal. That's when automated tracking comes in handy.

"This technology allows one to navigate through ultrasound, CT, any MRI sequence, or even PET scans," Wood said. "They are all available to you for real-time feedback while you are doing procedures."

U.S. interventionalists have focused on high-tech/low-cost models that-compared with most imaging equipment-are inexpensive to implement, entail short learning curves, and could be adopted rapidly upon validation, Wood said. "IRs are adept and very familiar with rapid change, new devices, and quick integration of technologies," Wood said. "Once [a technology's] specific benefits are proven, other people will follow."

Mr. Abella is associate editor of Diagnostic Imaging.