MRI Safety

Magnet Type  The MRI magnet used at MCH is the superconducting type. Superconducting magnets use a special wire which loses all resistance when cooled to -270 degrees Centigrade. This requires liquid helium to surround the magnet wire. Current is applied to the wire during instillation, which generates the magnetic field as it flows. Superconducting magnets are normally FULLY ENERGIZED at all times.

Magnetic Field  While MRI is considered to be a safe imaging technique, it is not without hazards. The magnet field will attract many ferromagnetic metals in an uncontrolled fashion and cause them to fly towards the magnets bore and turning them into high velocity projectiles. The bore of the magnet is where the fringe field is strongest, as all the lines of force are constricted and their relative strengths heightened. Various objects can be considered projectiles

Objects Considered to be Projectiles

Magnetic Field Cont…  The magnetic field extends outside of the poles of the magnet in all directions. It is always important to remember that the MRI magnet is the source of an invisible but powerful force, and this force grows considerably stronger as you come closer to the magnet.

 When transporting patients to the MRI suite always use non-magnetic stretchers, oxygen bottles, IV poles, and wheelchairs. These devices are normally located at the MRI suite, if you have any questions regarding what can and cannot enter the MRI vault consult the technologist Transporting Patients to MRI

Entering a Magnetic Field  Before entering the magnetic field you should remove all personal effects. The characteristics of the magnet field will harm digital and analog watches, magnetized strip on credit cards, pagers, radios, and some car alarm activators.

Precautions if Staying Inside the MRI Vault  Use auditory protection  If you have…  Pacemaker  Aneurysm Clips  Metal Orthopedic prosthesis  Ocular Implants  Dental Implants  Heart Valve Prosthesis  Intravascular Stents  Permanent Eyeliner Tattoos  Shrapnel Wounds  History of welder or machinist ALERT the Technologist BEFORE Entering the Magnetic Field

BE ALERT!!!!  Do not become a victim to the adverse effects of the magnet field, an incident can occur when you least expect it due to inattention.