Biomedical Imaging: Not Just a Pretty Picture
By Mary-Russell Roberson
“Imaging will become ubiquitous. Resolution limits will fall. Imagers will have impact in a whole array of new areas.”
These are the predictions of William Walker, a member of the panel discussing biomedical imaging at the 40th anniversary BME. Walker holds both an undergraduate and a doctoral degree in biomedical engineering from Duke and is now a professor of biomedical engineering at the University of Virginia. He’s also helped start several medical device companies.
The panelists, all of whom are Duke alumni, said the new generation of biomedical images contain a wealth of information that can be used to help doctors save lives.
“The field has matured,” said Joseph Lo. “We’re no longer satisfied with a pretty picture. You need to be able to measure something, to quantify something—so you can improve patient outcomes.” Lo has been at Duke’s biomedical engineering department since his freshman year in1984. He earned a BSE and PhD in the department and is now on the faculty.
Lo is working on an imaging technology called tomosynthesis to diagnose breast cancers. Tomosynthesis combines X-rays taken at several angles to create a 3D image.
“It’s a powerful tool when it comes to finding tumors,” he said. In a trial at Duke, tomosynthesis found two cancers in 300 subjects that were not found with other methods. Although the technology is available in other countries, it has not yet been approved by the FDA for use in the United States. For the future, Lo is excited about the possibilities of using tomosynthesis with ultrasound and molecular imaging to maximize detection ability.
Panelist Pat Scheller also talked about the emerging trend of combining information from multiple imaging technologies. She is president and CEO of Prescient Medical, Inc.
“We develop products to diagnose patients at risk for heart attacks and treat them prophylactically,” she said. “We shine a laser light on the wall of the artery to obtain a spectral signature, which gives us information about all the materials present. We can provide the cardiologist with a map of the inside of the artery.” She said the technique, which involves inserting a fiber-optic catheter into an artery, can be combined with ultrasound to provide an even more complete picture.
Bob Galloway creates biomedical images that help guide surgeons during surgery, a technique he calls image-guided therapy. He earned an undergraduate and a PhD degree in biomedical engineering at Duke and is now a professor of biomedical engineering and neurologic surgery at Vanderbilt University. “We use images not as pictures but as maps,” Galloway says. Real-time interactive images in the operating room show the target organ, the preplanned surgical plane, and the movements of the tools being used by the surgical team.
Susan Wood, president and CEO of VIDA Diagnostics, Inc., is also investigating the idea of using images to guide treatment. She’s working with imaging techniques that can be used not only to quantify and characterize lung disease, but also to guide the implantation of a device into an area of the lung with decreased function. “Chronic obstructive pulmonary disease is not homogenous,” she said. “These 3D images enable us to characterize disease by location and quantify it.” This allows customization of therapy to each individual.
A topic that came up more than once during the discussion was the difficulty of getting new medical devices and imaging techniques approved by the FDA today. Scheller said, “FDA problems are driving manufacturing dollars offshore and driving development dollars offshore.” She acknowledged the need to have a regulatory body to ensure safety, but she added, “There’s an economic price this country is paying.”
Wood said, “Companies are marketing in Europe because they can’t get approval here,” and Lo expressed frustration that the approval for breast tomosynthesis is taking so long. “I don’t think physicians have anything but enthusiasm for the technology,” he said.
Galloway agreed with those comments, but added that his European colleagues say some of the drugs and devices that get approved in Europe are not medically useful.
The imaging panel was moderated by Joseph Izatt and Kathryn Nightingale, both of whom are professors in Duke’s biomedical engineering department.