How to Prepare
Before the MRI test, tell your doctor and the MRI technologist if you:
- Have a pacemaker, artificial limb, any metal pins or metal fragments in your body (especially in the eyes), metal heart valves, metal clips in your brain, metal implants in your ear, tattooed eyeliner, or any other implanted or prosthetic medical device (such as a drug infusion pump). Also, tell your doctor if you have worked around metal or if you have recently had surgery on a blood vessel. In some cases you may not be able to have the MRI test done.
- Weigh more than 550 lbs. Please note that the diameter of the bore of the MRI is 70 cm.
- Have an intrauterine device (IUD) in place. An IUD may prevent you from having the MRI test done.
- Are or might be pregnant. In some cases, MRI may be done in late pregnancy to assess the fetus.
- Become very nervous in confined spaces. You need to lie very still inside the MRI magnet, so you may need to have the test done with open MRI equipment that is not as confining as conventional MRI machines, or you may need medication to help you stay relaxed. For certain MRI studies (such as of the legs or wrist), your body will be out of the confined space.
- Have allergies of any kind (such as hay fever, hives, food or medication allergies, or allergic forms of asthma). The contrast material used for MRI does not contain iodine. If you have a known allergy to the contrast material used for MRI, tell your doctor before having another test. Sometimes the benefits of having this test may outweigh the risks.
- You have any health conditions. Certain conditions (such as serious kidney problems or sickle cell anemia) may prevent you from having an MRI using contrast material.
- You will need to sign a consent form that says you understand the risks of an MRI of the head and agree to have the test done. Talk to your health professional about any concerns you have regarding the need for the test, its risks, or how it will be done.