Magnetic Resonance Imaging (MRI) has been hailed as a breakthrough in medical imaging, with MR scanners using magnetic fields and radio waves to visualize the internal structure of the human body, such as bones, organs, and muscles. It is able to provide images of soft tissue with better detail and contrast than both CT scans and X-rays without using ionizing radiation, giving physicians more information about the patient’s condition and better informing their next course of action. The technology was developed in the 1970s by physicists Peter Mansfield and Paul Lauterbur, earning them the Nobel Prize in 2003.
However, due to the strong magnetic fields and radio waves used in MRI, there are significant safety precautions that need to be taken into account. Magnetic objects should not be brought into the same room as an operational MR scanner, as they could be sucked towards the machine at high speed, potentially injuring people. Additional care must be taken with patients who have medical devices attached to them or implants that could be affected by the magnetic fields or radio waves used in MRI. Around 10% of Americans will have a medical device implanted in their bodies at some point in their lives, making this a significant issue for patients, health providers, and medical device and MR scanner manufacturers.
According to Dr. Wolfgang Kainz, President and CEO of HPC for MRI Safety and former Senior Biomedical Engineer at the US FDA’s Center for Devices and Radiological Health (CDRH), it is very important for device manufacturers to ensure that their products are safe for use in patients undergoing MRI to avoid serious discomfort or injury.
Dr. Kainz explains that MR scanners use three types of fields: a static magnetic field, a gradient magnetic field, and a radio frequency field. The static magnetic field is up to 200,000 times stronger than the Earth’s magnetic field and could turn medical devices with magnetic properties into projectiles. On the other hand, the radio frequency field causes tissues and electrically conductive medical devices to heat up, similar to how a microwave oven works. The possibility of torque or heating that can lead to injuries to the patient and medical personnel is a serious problem and, in the distant past, anyone who had a medical implant was contraindicated for MRI. This included both passive implants (unpowered devices such as stents, screws, and joint replacements) and active implants (battery-operated devices, such as pacemakers and deep brain stimulators).
However, with more people living with implants, determining which ones are safe for MRI has become more important. In relation to MRI, the FDA classifies medical devices into three categories: MR Unsafe, MR Conditional, and MR Safe. Medical devices labeled as MR Conditional can only be safely scanned if the conditions in the MRI labeling are closely followed, as any off-label scans might pose a high risk to the patient.
Having been part of the FDA’s CDRH for around 20 years, Dr. Kainz, who holds a PhD in Technical Science from the Technical University of Vienna, was the FDA’s primary liaison to various standard-setting bodies related to MRI safety for both passive and active implants. He helped develop international standards and FDA Guidances for medical device manufacturers to follow and ensure that their products are safe in the MR environment. He also reviewed more than 1,000 MRI safety-related submissions to the FDA and published hundreds of peer-reviewed publications on MRI safety.
In 2022, Dr. Kainz founded HPC (High Performance Computing) for MRI Safety, a consulting firm that uses the latest computer hardware and software to evaluate medical devices for MRI safety. While still working at the FDA, Dr. Kainz developed sophisticated and anatomically correct computer models of humans used to accurately simulate the effects of MRI on the patient’s body and any implanted devices. Today, models for the entire patient population are available, i.e., from babies, kids, and adults to elderly patients, obese patients, and even pregnant women, for greater accuracy. Computer simulations are often more affordable than bench tests and allow HPC for MRI Safety and device manufacturers to iterate their tests more quickly, leading to significant efficiency improvements.
Dr. Kainz and his team have more than 20 years of experience dealing with regulatory bodies of major markets, such as the US, the EU, and China, which helps clients more successfully navigate the regulatory processes in these jurisdictions.
According to Dr. Kainz, obtaining safe and effective MR labeling for medical devices should be the goal of device manufacturers, and this begins early in the product design process. This means that MRI safety should be a crucial component early in the design process for any medical device seeking MR labeling. When the MR Conditional labeling is not as effective as it could be, the MR scan is suboptimal, which could lead to lower imaging quality and longer scan times and may prevent certain body parts from being scanned at all, which is disadvantageous to the patient.
He adds that device manufacturers can benefit by working early on in the design phase with MRI safety experts who also have the necessary regulatory knowledge, such as HPC for MRI Safety. This will help them determine the most effective and Least Burdensome Provisions to acquire safe and effective MR labeling. Incorporating these experts early in the design process will result in cost savings for manufacturers because it avoids having to go back to the drawing board if something is found to be MR Unsafe or less effective in MR Conditional labeling.
HPC for MRI Safety also helps manufacturers create effective regulatory submissions for their devices, using the FDA’s Least Burdensome Provisions to minimize deficiencies and delays.
“MRI is a huge benefit to patients and their physicians, who have a powerful imaging tool that gives them accurate and detailed information about the patient’s internal condition,” Dr. Kainz says. “With medical devices and implants becoming more common and MRI more accessible, it’s of paramount importance that these devices are properly labeled, easily understood by the user, and closely followed to avoid accidents during MRI. HPC for MRI Safety uses advanced technology in hardware and software, including GPU accelerated workstations and the latest modeling tools, to create highly accurate computer simulations aiding device manufacturers in achieving safe and most effective MR labeling. We provide full support, from the design phase to the regulatory submission, ensuring the greatest chance of approval in the shortest time possible.”
Media contact:
Name: Dr. Wolfgang Kainz
Email: [email protected]
