Program looks to build a safer implant

While more than 120,000 Canadians have pacemakers – and an estimated 25,000 new ones are implanted each year – these patients are unknowingly putting themselves at risk of a lower standard of care down the road.

Between 50-75 per cent of patients with pacemakers will need a magnetic resonance (MR) scan over the device’s lifetime. As of right now, all will be denied that service because most standard medical devices either cease to operate, or present a danger to the patient, when within the MR environment.

Some of the major technical challenges associated with using any medical device in the MR environment can include radiofrequency, heating, device-induced image distortion, device/scanner interference, among others.

Western Physics and Astronomy professor Blaine Chronik looks to end that through a Canadian-first program to develop MR-compatible medical devices. He and his team are working on building better standards by assisting close to a dozen major companies assuring their medical device products are safe for the public.

Toward that end, Chronik recently received a $705,911 Canada Foundation for Innovation (CFI) award to facilitate his research.

“People who get implanted devices – a pacemaker is a great example – are getting this excellent standard of care with this device. But as soon as you get it, you are more or less eliminated from the MR,” Chronik said. “That creates a problem.”

And the numbers are massive.

In 2009, there were 266 MRI systems installed in Canada, an increase of 70 per cent over 2004 levels. And they were busy machines. In 2008-09, there were 620,357 MR exams in Ontario and more than 1.3 million across Canada.

Each year, more than 200,000 patients in the U.S. receive a pacemaker, and it is estimated more than 5 million people worldwide currently have pacemakers.

And while pacemakers are just one example, the problem also affects people with orthopedic, cardiac, dental and cochlear implants, as well as trauma fixation devices, insulin pumps, neurostimulators, vascular stents and physiological monitoring devices.

“MR-compatible medical device development is a highly complex problem whose solution requires access to a dedicated facility and appropriate expertise, which is currently absent in Canada,” he said. “This project aims to improve health care for Canadians by facilitating the development of safer, more advanced medical devices for use within safer, more advanced MR systems.”

Proximity and access to Western’s top imaging facilities will give companies an additional advantage in the competitive medical device industry, added Chronik.

So why not just change what the medical device is made of?

“It’s easy to imagine it’s just material selection. Most companies start with that, go into production and then hit a wall,” Chronik said. “Every single device is a challenge. If you change one thing, you have to re-demonstrate and understand whether you are MR-safe or not. And MRIs are changing each year, so at the same time we are helping companies look ahead to anticipate that.”

While doing similar work over the last number of years, Chronik said this latest CFI award would dramatically increase his ability to do more.

“It’s like crash testing a car,” he said. “Piece by piece we can test in the lab these interactions so that, before we go into the scanner, we are able to help this company and figure out exactly what’s wrong with it and how to fix it. And we do fix it, but we still have to do the crash test, but that’s the last stage.

“But now in the lab we can test each components interaction – a better test and more cost effective. Our goal is to be the go-to-guys worldwide. When somebody somewhere needs to get something in a scanner and they don’t know how to do it, ‘we got to go to Western.’”

While the only ones in Canada doing such work, Chronik said medical devices are also being tested and given MR-safe labeling by regulatory agencies elsewhere, so “clearly we are not inventing this field.”

“However, we would argue that no other group or institution has ‘put it all together.’ It is certainly the case that any MR scientist with access to a scanner can conduct some degree of MR device evaluation and testing,” he said. “The difference is the lack of a comprehensive program that covers all aspects of device testing and development. We want to take the power and advantages of being in an academic university, with the students, all the training and resources we have, like CFI, and be as responsive and quality driven as any registered consulting company.”

The work around the testing and development facility will have a true interdisciplinary element, evident from the CFI application. Represented are three universities – Western, Alberta and McMaster – as well as seven departments including work with Western researchers Jody Culham, Psychology/Social Science; Aaron Fenster, Robarts Research Institute; David Holdsworth, Surgery; Ravi Menon, Robarts Research Institute; Shaun Salisbury, Mechanical & Materials and Electrical & Computer Engineering; Kevin Shoemaker, Kinesiology; and John de Bruyn, Physics and Astronomy.