Combining radiation and magnets: factors to consider when creating a PET/MR safety policy

Objectives: PET/MR is a combination of two modalities that each represents unique safety concerns. As an innovational hybrid modality, staffed by technologists that are knowledgeable in their own modality, it is important to develop a comprehensive safety policy and procedure that includes the unique considerations of both fields. Methods: A work group of staff from Nuclear Medicine (NM), Magnetic Resonance Imaging (MR), Nursing, Physics, and Radiation Safety was formed to develop a PET/MR safety policy. The entire PET/MR space and workflow was reviewed, discussing any factors from a radiation or magnet perspective, and documented to provide education and guidance to staff. Radiation Safety concerns included area surveys, spill potential, ALARA principles, personnel monitoring, and pregnancy screening. Considerations from an MR standpoint included magnet safety, patient screening, quench potential, acoustical noise, radiofrequency interference, and access pathways. Areas where the two factors conflicted were discussed to develop a resolution. For example, area monitoring must be performed, however a GM meter which is not MR compatible, cannot be brought into the scan room. Therefore, wipe tests are used for daily surveys, weekly wipes, and in the event of a spill. Some areas had overlap, where both NM and MR input needed to be combined such as patient screening. A PET/MR patient must have appropriate screening for MR safety but also screening for pregnancy potential to ensure radiation safety. NM staff required MR safety training to understand the potential risks of the magnet, not only from a metallic object perspective, but also from an operational perspective to recognize a quench and prevent patient burns. MR staff were issued badges to monitor exposure and educated on radiation safety to include time, distance, and shielding, spill containment, and the definition of a Radioactive Material Area in relation to such things as food and drink. Results: A PET/MR safety policy was developed and shared with staff working in the area. This document is reviewed and updated on a regular basis as the field of PET/MR safety continues to evolve. Technologists received education and hands-on training specific to the opposite modality. To date, no safety events from either an NM or MR perspective have occurred. Conclusion: With the proper preparation and a multi-modality work group, PET/MR can operate as a safe practice, despite the significant number of distinct con