New federal draft guidance details how to determine whether medical devices and implants can safely enter a magnetic resonance imaging (MRI) machine, which may expose the devices to powerful magnetic fields that could dangerously interact with metal and electrical systems in patients’ bodies.
The FDA draft guidance was issued earlier this month, titled “Testing and Labeling Medical Devices for Safety in the Magnetic Resonance Environment,” providing information about medical devices that are intended to enter the MR environment, such as pacemakers, neurostimulators, insulin pumps, artificial heart valves, and cochlear implants.
Traditionally, many medical devices and implants cannot enter a MRI machine, because they are metallic and can cause abnormalities to the images or potentially harm the patient. However, manufacturers have begun designing versions of medical devices that are MRI compatible. Nearly 70% of pacemakers implanted in 2018 were MRI-compatible up from 12% in 2016.
The draft guidance details how to undertake testing to assess the safety and compatibility of medical devices in the MR environment and the recommended format for magnetic resonance imaging. The guidance also includes improvements to safety of MR environments and MRI related medical device labeling.
The draft guidance reviews hazards linked to medical devices brought into the MRI including magnetic induced displacement force, magnetic induced torque, and heating of tissue near the medical device.
Medical devices entering the MR environment can have a direct impact on how providers diagnose and treat patients. Having active medical devices can cause the images to be corrupted, it can lead to images that can’t be interpreted or lead to a diagnosis, and can cause disease-mimicking artifacts, or fake items on the images.
The FDA guidance called for this hazard to be addressed for all medical devices which will be allowed to enter the MRI machine. The agency indicates manufacturers should include summaries of their test reports. The hazard being tested and the equipment should also be listed.
The devices should also include safety labeling, indicating the device is “MR Safe,” “MR Unsafe,” or “MR Conditional” to indicate if they can be brought into the MR environment, should remain outside, or have special guidance for use in the MRI machine, the draft guidance states.
Public comments on the draft guidance will be accepted until Oct 1, 2019. Comments can be submitted online, or by mail to Division of Dockets Management (HFA-305), Food and Drug Administration, 5630 Fishers Lane, Rm. 1061, Rockville, MD 20852.
All written comments must be identified with docket number FDA-2019-D-2837.