Epix works with vendors to ensure contrast agent compatibility

April 26, 2000

Equipment performance inevitably affects contrast agent performance; the quality of an image cannot be better than the scanner can deliver. This is especially true for intravascular MRI agents, which depend on hardware and software developments to reach

Equipment performance inevitably affects contrast agent performance; the quality of an image cannot be better than the scanner can deliver. This is especially true for intravascular MRI agents, which depend on hardware and software developments to reach their full potential.

Epix Medical is reaching out to equipment vendors, creating partnerships designed to ensure that its new vascular agent, called AngioMark, will be compatible with MRI scanners and workstations. The idea is to coordinate and integrate product development and marketing before AngioMark, which is now in phase III clinical trials, passes the FDA.

“Our relationships with MRI equipment vendors, software developers, and clinical researchers will put us in a unique position to replace a large percentage of x-ray angiography procedures with noninvasive MRI methods to diagnose and help manage cardiovascular disease,” said Gregg Mayer, Epix vice president and business manager for AngioMark.

Epix hosted a panel discussion on this topic March 28 at the BIO 2000 symposium in Boston, where representatives of GE Medical Systems, Vital Images, Epix, and the user community addressed the challenges of developing hardware, imaging software, and contrast agents.

The driving force behind this integrated development is the persistence of AngioMark in the bloodstream, Mayer said. Whereas current MRI agents circulate for only a few seconds, AngioMark remains in the bloodstream for an hour or more, meaning that it will be visible in venous as well as arterial circulation. This requires manufacturers to tweak their equipment with special real-time image processing and visualization tools to capture selected information. These acquisitions are later complemented by software that generates high-resolution images of specific areas.

Several projects are under way with academic collaborators to develop computer algorithms that automatically separate arteries and veins, according to Mayer. Meanwhile, vendors are working on “temporal labeling” routines, he said. These are being designed to separate arteries and veins by calculating the arrival of contrast agents. The trick is to make these acquisitions as easy and transparent as possible for users.

“We want to develop automated scanning sequences, image processing, and visualization tools to make this a simple ‘light-switch’ operation in the clinic,” Mayer said. “Our equipment collaborators, like GE, Philips, and Siemens, are all working on techniques to do this and they’re as confident as we are that by the time (AngioMark) hits the market, we’ll have it whupped.”

The development of these automated tools is taking place in an environment of change, said Andrew Hayes, GE Medical Systems’ manager of cardiovascular MR.

“The trend is to go from optimized to dedicated (cardiovascular) systems and from systems being used by radiologists or highly specialized workers to an environment where (cardiologists) will be involved in MR,” Hayes said.

The challenge is to make accessible these increasingly complex scanners, which may be using novel high-resolution coils, contrast agents, and new postprocessing capabilities, so that physicians who have little knowledge of MRI can generate consistent and reproducible results.

“Experts in MR are not experts in cardiac disease and the people who are experts in cardiac have to learn to become experts in MR, if they are going to take this on,” Hayes said.

The means for accomplishing this transition may be the development of visualization tools that preserve a normal workflow for specialists in cardiovascular medicine. A critical part of preserving this flow is development of the means for efficiently analyzing image data.

“Physicians need a simple and fast and affordable productivity tool that allows them to look at 2-D images and 3-D data sets,” said Jay Miller, senior vice president and general manager of Vital Images. “In a number cases, it is easier to see things in 3-D than it is to see them in 2-D. That is certainly true for those of us who are not radiologists, such as referring physicians, surgeons, and interventionalists.”

Along with these new ways to visualize, Vital Images is creating tools that automatically measure, for example, a blood vessel lumen, so as to calculate the size of the stent to be implanted.

To be effective, however, development of these tools must be part of the coordinated improvement of contrast agents and scanner technology. This, said Dr. Steven Wolff, director of cardiovascular MRI at Integrated Cardiovascular Therapeutics in Woodbury, NY, is only the beginning.

“Intravascular contrast agents are driving the equipment manufacturers to take advantage of new agents by designing coils, software to move the table, and new hardware that will allow cardiac catheter interventions to be performed,” Wolff said. “The main impediment so far has been ease of use. And the equipment manufacturers are working on that.”