What happens before a magnetic resonance imaging (MRI)?

The following are the things you need to know before a magnetic resonance imaging (MRI) -- a diagnostic procedure that uses a combination of a large magnet, radiofrequencies, and a computer to produce detailed images of organs and structures within the body:
  • Your physician will explain the procedure to you and offer you the opportunity to ask any questions that you might have about the procedure.
  • If your procedure involves the use of contrast dye, you will be asked to sign a consent form that gives permission to do the procedure. Read the form carefully and ask questions if something is not clear.
  • Notify the technologist if you have ever had a reaction to any contrast dye, or if you are allergic to iodine or seafood.
  • Generally, there is no special restriction on diet or activity prior to an MRI procedure.
  • Notify the technologist if you are pregnant or suspect you may be pregnant.
  • Before the examination, it is extremely important that you inform the technologist if any of the following apply to you: you are claustrophobic and think that you will be unable to lie still while inside the scanning machine, in which case you may be given a sedative; you have a pacemaker or have had heart valves replaced; you have any type of implanted pump, such as an insulin pump; you have metal plates, pins, metal implants, surgical staples, or aneurysm clips; you have any metallic fragments anywhere in the body; you have permanent eye liner or tattoos; you are pregnant or suspect you may be pregnant; you ever had a bullet wound; you have ever worked with metal (e.g., a metal grinder or welder); you have any body piercing; you have an intrauterine device (IUD).
  • Sedative medication may be given if you have claustrophobia and/or anxiety that would make it difficult for you to remain still during the procedure.
  • Based upon your medical condition, your physician may request other specific preparation.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.