Risks
By Mayo Clinic staffThe presence of metal in your body may be a safety hazard or affect a portion of the MRI image. Tell the technologist if you have any metal or electronic devices in your body, such as:
- Metallic joint prostheses
- Artificial heart valves
- An implantable heart defibrillator
- A pacemaker
- Metal clips to prevent aneurysms from leaking
- Cochlear implants
- A bullet, shrapnel or any other type of metal fragment
Also tell the technologist if you think you're pregnant, because the effects of magnetic fields on fetuses aren't well understood. Your doctor may recommend choosing an alternative exam or postponing the MRI.
It's also important to discuss any kidney or liver problems with your physician and the technologist, because problems with these organs may impose limitations on the use of injected contrast agents during your scan.
- Neurological diagnostic tests and procedures. National Institute of Neurological Disorders and Stroke. http://www.ninds.nih.gov/disorders/misc/diagnostic_tests.htm. Accessed Sept. 2, 2010.
- Patient safety: Magnetic resonance imaging (MRI). American College of Radiology, Radiological Society of North America. http://www.radiologyinfo.org/en/safety/index.cfm?pg=sfty_mr. Accessed Sept. 2, 2010.
- MRI of the head. American College of Radiology, Radiological Society of North America. http://www.radiologyinfo.org/en/info.cfm?pg=headmr. Accessed Sept. 2, 2010.
- Functional MR imaging (fMRI) — Brain. American College of Radiology, Radiological Society of North America. http://www.radiologyinfo.org/en/info.cfm?pg=fmribrain. Accessed Sept. 2, 2010.
- Cardiac MRI. American College of Radiology, Radiological Society of North America. http://www.radiologyinfo.org/en/info.cfm?pg=cardiacmr. Accessed Sept. 2, 2010.
- MR angiography (MRA). American College of Radiology, Radiological Society of North America. http://www.radiologyinfo.org/en/info.cfm?pg=angiomr. Accessed Sept. 2, 2010.
- MRI of the body (chest, abdomen, pelvis). American College of Radiology, Radiological Society of North America. http://www.radiologyinfo.org/en/info.cfm?pg=bodymr. Accessed Sept. 2, 2010.
- MRI of the musculoskeletal system. American College of Radiology, Radiological Society of North America. http://www.radiologyinfo.org/en/info.cfm?pg=muscmr. Accessed Sept. 2, 2010.
- MRI of the breast. American College of Radiology, Radiological Society of North America. http://www.radiologyinfo.org/en/info.cfm?pg=breastmr. Accessed Sept. 2, 2010.

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