CII Food Drive

Implants

All patients are reviewed for contraindications prior to MRI scanning. Medical devices and implants are categorized as MR Safe, MR Conditional or MR Unsafe: ^[44]

MR-Safe — The device or implant is completely non-magnetic, non-electrically conductive, and non-RF reactive, eliminating all of the primary potential threats during an MRI procedure.
MR-Conditional — A device or implant that may contain magnetic, electrically conductive or RF-reactive components that is safe for operations in proximity to the MRI, provided the conditions for safe operation are defined and observed (such as ‘tested safe to 1.5 teslas’ or ‘safe in magnetic fields below 500 gauss in strength’).
MR-Unsafe — Objects that are significantly ferromagnetic and pose a clear and direct threat to persons and equipment within the magnet room.

The MRI environment may cause harm in patients with MR-Unsafe devices such as cochlear implants and most permanent pacemakers. Several deaths have been reported in patients with pacemakers who have undergone MRI scanning without appropriate precautions.^[45]Many implants can be safely scanned if the appropriate conditions are adhered to and these are available online (seewww.MRIsafety.com). MR Conditional pacemakers are increasingly available for selected patients. ^[46]

Ferromagnetic foreign bodies such as shell fragments, or metallic implants such as surgical prostheses and ferromagnetic aneurysm clips are also potential risks. Interaction of the magnetic and radio frequency fields with such objects can lead to heating or torque of the object during an MRI.^[47]

Titanium and its alloys are safe from attraction and torque forces produced by the magnetic field, though there may be some risks associated with Lenz effect forces acting on titanium implants in sensitive areas within the subject, such as stapes implants in the inner ear.

The very high strength of the magnetic field can also cause “missile-effect” accidents, where ferromagnetic objects are attracted to the center of the magnet, and there have been incidents of injury and death.^[48]^[49] To reduce the risk of projectile accidents, ferromagnetic objects and devices are typically prohibited in the proximity of the MRI scanner and patients undergoing MRI examinations are required to remove all metallic objects, often by changing into a gown or scrubs, and ferromagnetic detection devices are used at some sites.^[50]^[51]

There is no evidence for biological harm from even very powerful static magnetic fields.^[52]

In order to ensure your exam does not have to be rescheduled, one of our staff members will contact you by phone to conduct the interview in the days leading up to your appointment. If you would like to speak with our screening staff please call 559.325.5800.