Biomedical implants and devices: Assessment of magnetic field interactions with a 3.0‐Tesla MR system

TLDR

The study evaluates magnetic field interactions of 109 biomedical implants and devices during exposure to a 3.0‑Tesla MR system. Using standardized techniques, the authors measured translational attraction and torque for each device at 3.0‑Tesla. Four percent of the devices exhibited deflection angles above safety limits, with angles up to 90° and torques up to +4, highlighting potential risks during 3.0‑Tesla MR procedures and underscoring that results are specific to this system. © 2002 Wiley‑Liss, Inc., J.

Abstract

Abstract Purpose To evaluate magnetic field interactions for 109 different biomedical implants and devices in association with exposure to a 3.0‐Tesla magnetic resonance (MR) system. Materials and Methods A total of 109 implants and devices (aneurysm clips, 32; clips, fasteners, and staples, 10; coils and stents, 10; heart valve prostheses and annuloplasty rings, 12; orthopedic implants, five; suture materials, 13; vascular access ports and accessories, 13; miscellaneous implants and devices, 14) were tested for magnetic field interactions at 3.0‐Tesla using previously‐described, standardized techniques to assess magnetic field translational attraction and torque. Results The deflection angles and torque measurements ranged, respectively, from 0 to 16° and 0 to +2 for the aneurysm clips; 0 to 90° and 0 to +4 for the clips, fasteners, and staples; 0 to 47° and 0 to +4 for the coils and stents; 0 to 4° and 0 to +1 for the heart valve prostheses and annuloplasty rings; 0 to 12° and 0 to +2 for the orthopedic implants; 0 to 13° and 0 to +2 for the suture materials; 0 to 52° and 0 to +4 for the vascular access ports and accessories; and 0 to 28° and 0 to +3 for the miscellaneous implants and devices. Conclusion Of the 109 implants and devices assessed for magnetic field interactions at 3.0‐Tesla, four (4%) are potentially unsafe based on deflection angle criteria. The implications of these results for patients undergoing MR procedures at 3.0‐Tesla is discussed. Notably, these results are specific to the 3.0‐Tesla MR system used for this evaluation. J. Magn. Reson. Imaging 2002;16:721–732. © 2002 Wiley‐Liss, Inc.