Your doctor or an MRI technician will ask you some questions before the test, such as:
Your answers will help your doctor decide whether you should have chest MRI.
Your doctor or technician will ask you to not wear or bring metal, electronic, or magnetic objects into the MRI room. Examples include:
MRI magnets can damage these objects, or the objects may interfere with the MRI machine.
The MRI machine looks like a long, narrow tunnel. During the MRI, you lie on your back on a sliding table. The table passes through the scanner as it takes pictures of your chest. Newer machines are shorter and wider and don't completely surround you; others are open on all sides.
Tell your doctor if you're afraid of tight or closed spaces. He or she may give you medicine to help you relax, or find you a place that has an open MRI machine.
If you receive medicine to relax you, your doctor may ask you to stop eating about 6 hours before you take it. This medicine may make you tired, so you'll need someone to drive you home.
Your doctor may inject a substance called contrast dye into a vein in your arm before the MRI. You may feel some discomfort where the needle is inserted. You also may have a cool feeling as the dye is injected.
Contrast dye allows the MRI to take more detailed pictures of the structures in your chest. The dye used for chest MRIs doesn't contain iodine, so it won't create problems for people who are allergic to iodine. Rarely, people develop allergic symptoms from the dye, such as hives and itchy eyes. If this happens, your doctor can give you medicine to relieve your symptoms.
If you're breastfeeding, ask your doctor how long you need to wait after the test before you breastfeed. The contrast dye can be passed to your baby through your breast milk.
You may want to prepare for the test by pumping and saving milk for 24 to 48 hours in advance. You can bottle-feed your baby in the hours after the test.
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