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Ency. home > Test > M > MRI
MRI
Magnetic resonance imaging; Nuclear magnetic resonance (NMR) imaging
What the Risks Are There is no ionizing radiation involved in MRI, and there have been no documented significant side effects of the magnetic fields and radio waves used on the human body to date. The most common MR intravenous contrast agent, gadolinium, is very safe, and although there have been documented allergic reactions to it, this is extremely rare. If sedation is used, there are associated risks of over-sedation. The technologist monitors the patient's vital signs, including heart rate and respiration as needed. However, because the effects of strong magnetic fields on a fetus are not well documented at this time, pregnant women are usually advised to avoid MRI scans. People have been harmed in MRI machines when they did not remove metal objects from their clothes or when metal objects were left in the room by others.
MRI is usually not recommended for acute trauma situations, because traction and life-support equipment cannot safely enter the scanner area and scan times are relatively lengthy.
For specific information about why the test is performed and normal and abnormal results, please see the specific MRI topics:
Ency. home > Test > M > MRI

