FDA has finalized guidance on the safety testing and labeling of medical devices that may be used in the magnetic resonance environment.
The final document, which arrives 21 months after the draft was released for consultation, sets out recommendations for testing the safety and compatibility of medical devices in the area around the magnets used in MR imaging equipment.
FDA has retained the structure of the draft document but changed many of the details about how medical device developers should test if their products are safe in the MR environment.
FDA received little feedback on the 2019 draft. Cook Medical, the only medical device manufacturer to submit a public comment, was broadly upbeat about the draft, commending FDA for addressing the perceived limitations of its 2014 guidance and for incorporating references to ISO standards into the document.
The draft, like the 2014 text, also referenced standards from ATSM, the organization formerly known as the American Society for Testing and Materials. Cook welcomed the continued inclusion of those standards but flagged up a potential issue with the timing of FDA’s guidance.
Writing in 2019, Cook told FDA: “Many of the changes in these ASTM standards and guidance documents have not yet been agreed upon by the working groups. However, elements from these draft ASTM standards and guidance documents have been included in FDA's new draft guidance.”
Cook highlighted a potential for conflicts if the agency’s guidance was based on draft ATSM standards that were changed during the finalization of those documents. Cook asked FDA for feedback on how it planned to avoid conflicts and causing “confusion for industry and global regulatory authorities.”
Between the release of the draft and final FDA guidance documents, ATSM has published two books that feature the standards referenced by the U.S. regulator. FDA added a paragraph to its final text to explain that the ATSM and ISO standards may be useful when assessing the safety of medical devices in the MR environment.
Other changes made by FDA in the final guidance relate to its recommendations on testing medical devices. For example, the final guidance features additional information on how to assess the effect of magnetically induced displacement force, explaining that manufacturers should test whether the carts and stands used to mount large medical devices tip or topple in the MR environment.
FDA has scheduled a webinar to discuss the guidance and answer questions about it for June 24.