The draft guidance issued offers updated testing and labeling advice to assess the safety and compatibility of medical devices for the magnetic resonance (MR) environment.
Once finalized, the 26-page draft guidance from the US Food and Drug Administration’s (FDA) Center for Devices and Radiological Health (CDRH) will supersede final guidance issued in 2014. The recommendations in the new draft guidance go beyond those set forth in 2014, particularly as it relates to mitigating the safety hazards unique to the MR environment and device labeling.
“MRIs are powerful tools for health care professionals to diagnose medical conditions & guide certain procedures,”
The draft guidance addresses “a broader range of devices,” including active implants and ancillary medical equipment, and it outlines “clearer labeling” with the goal of helping “health care professionals better consider potential hazards.”
The draft clarifies whether and how to address each hazard depending on the device type, as well as how to format assessments and labeling information that should be included in premarket submissions.
“Appropriate testing and analyses, scientific rationale, and labeling, such as well supported MR conditional labeling…form the basis of adequate mitigations for the unique safety hazards of the MR environment,”
New recommendations include mitigation measures for gradient induced variation and extrinsic electrical potential, the rectification of radiofrequency pulses from MR exams and device malfunctions. This is in addition to magnetically induced displacement force, magnetically induced torque, heating and image artifacts hazards discussed in the 2014 guidance.
With recommendations for mitigation measures across a wider range of hazards, CDRH seeks to help minimize the risks posed by devices that enter the MR environment. These include tissue damage and image corruption, among others. To mitigate the potential of a device used in the MRI room but not the MR system bore becoming a projectile, CDRH is proposing that such a device “be permanently secured so that it may not be moved into a hazardous area.”
The draft guidance newly proposes providing test report summaries and complete test reports, if applicable. It also identifies the information that should be included in such summaries or reports.
Updates make new recommendations for using a “patient medical device card,” though implant cards and patient cards have been a requirement on certain device types like breast implants and hearing aids for years. CDRH now says that patient labeling for in-scope implants and external devices fastened to or carried by patients should also include a patient medical device card so that the medical professional can identify the specific devices a patient has, the MRI safety status of the devices and the conditions for the safe use of MR Conditional devices.
FDA raised concerns in 2017 with implantable infusion pumps in the MR environment after receiving serious adverse events reports of patient injury and death, recommending patients with such devices and their caregivers use an implant card. The required inclusion of an implant card was introduced in Europe in May 2017, followed by Australia in August 2017. EU guidance on implant cards was posted last month.
The draft guidance also places greater emphasis on leveraging additional consensus standards and FDA guidances made available since 2014. These include ISO and IEC standards and guidances on Q-submissions, 510(k) submissions for MR diagnostic devices, among others.