Biomedical implants and devices: assessment of magnetic field interactions with a 3.0-Tesla MR system.
OBJECTIVE
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.


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 degrees and 0 to +2 for the aneurysm clips; 0 to 90 degrees and 0 to +4 for the clips, fasteners, and staples; 0 to 47 degrees and 0 to +4 for the coils and stents; 0 to 4 degrees and 0 to +1 for the heart valve prostheses and annuloplasty rings; 0 to 12 degrees and 0 to +2 for the orthopedic implants; 0 to 13 degrees and 0 to +2 for the suture materials; 0 to 52 degrees and 0 to +4 for the vascular access ports and accessories; and 0 to 28 degrees and 0 to +3 for the miscellaneous implants and devices.


CONCLUSIONS
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.
Shellock
Frank G
FG
University of Southern California, Keck School of Medicine, Los Angeles, California, USA. frank.shellock@gte.net
D001672:Biocompatible Materials; D004869:Equipment Safety; D004864:Equipment and Supplies; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000009:adverse effects*; D019736:Prostheses and Implants; D019415:Torque
D001672:Biocompatible Materials