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MR procedures and biomedical implants, materials, and devices: 1993 update.

PURPOSE
To provide information on ferromagnetic metallic implants, materials, and devices that may be exposed to static magnetic fields during magnetic resonance (MR) imaging or spectroscopy.


MATERIALS AND METHODS
An updated compilation of the results of more than 80 studies lists the specific object tested, the material used to construct the object, whether the object was deflected or moved during exposure to the static magnetic field, and the highest field strength used for testing the object (range, 0.147-4.7 T).


RESULTS
The ferromagnetic qualities of 338 objects (32 aneurysm and hemostatic clips; six biopsy needles; five carotid artery vascular clamps; 18 dental devices or materials; 11 halo vests; 29 heart valve prostheses; 20 intravascular coils, filters, and stents; 22 ocular implants; 30 orthopedic implants, materials, and devices; 62 otologic implants; 23 pellets and bullets; 13 penile implants; 38 vascular access ports; and 29 miscellaneous objects) are reported.


CONCLUSION
MR imaging or spectroscopy may be contraindicated in patients with such objects because of the risk of movement or dislodgment of the object.