Note: The following preps are for outpatient care only. For questions about any of these preps, please contact the Radiology Reception Desk, at (734) 936-4500 for more information.
What is MRI?
Magnetic Resonance Imaging (MRI) provides physicians with a method of visualizing your internal body structures. This technology enables physicians to detect developing diseases or abnormalities earlier than ever before. Basically MRI involves a powerful but harmless magnetic field and radiowaves like the kind that transmit your favorite FM music. The combination of radio waves and magnetic field produces very clear images of body structures such as the brain, spine, knee, kidney, liver, blood vessels, heart and other important structures.
What Kinds of Machines Are Used to Perform MRI? Does MRI Hurt?
Your scan will be performed in a room containing a MRI machine. The MRI unit looks like a large circle, open on both ends. Many times referenced to look like a bagel or a doghnut. You will be asked to lie on a comfortable, padded table that is gently moved into the opening of the magnet where the scanning is performed. Sometimes a "coil", which is really just a special camera, will be placed around the body part being scanned (your head, or knee, or stomach, etc.). The data from the scan is fed into computers which turns it into pictures that the physician will use to make a diagnosis. MRI itself is a painless procedure. To date, millions of patients have experienced MRI and the procedure has been proven to be extremely safe.
Is MRI For Everybody?
While the great majority of people can undergo an MRI exam with no problems, some cannot. The radiologist or the staff at the MRI center will probably ask you questions like the following:
- Height and weight?
- Can you lie flat for an extended period of time?
- Do you suffer from claustrophobia (fear of tight or closed spaces)?
- Might you be pregnant?
Since the MRI scan involves the use of a powerful magnet you will be asked the following kinds of questions:
- Do you have any implanted devices such as a cardiac pacemaker, a cerebral aneurysm clip, a neurostimulator, a hearing aid?
- Do you have any metal shrapnel in your body or any metal fragments in your eyes?
Remember that the questioning process is a two-way street. After providing all of the necessary information, feel free to air any concerns you may have about the upcoming examination. Don't be afraid to ask! Radiologists and technologists expect questions and part of their job is answering them.
What Happens the Day of the Exam?
You should allow about two hours for your MRI exam, although most scans take an hour or less. If you are having an MRI of your abdomen (such as for your liver or kidneys), please avoid eating or drinking for 4 hours before the study. For all other MRI studies, you can eat normally for the day of your exam unless your doctor or the MRI department specifically tells you otherwise. Any medication that is needed should be taken as prescribed with a small amount of water, unless otherwise instructed by the Radiology Department. Don't wear any makeup, since some brands contain metallic components. Before you arrive for your MRI please remove any body piercings (studs, rings, etc) as they can heat up in the magnetic field. When you arrive at the MRI center, you will be asked to put on a patient gown and to remove all personal possessions such as your watch, wallet and car keys or metallic items such as dentures, pins, etc. It's very important not to take anything that could be affected by a magnet into the examining room. For example, the information on your credit cards will be erased if you have them in your pocket during the exam.
What Happens During the Actual Exam?
You will be escorted into the room containing the MRI unit by a technologist. You'll be given a pair of earplugs and headphones to decrease the noise encountered during the examination and asked to lie down on the padded table. Then the technologist will position you inside the magnet so that the appropriate part of your body is ready to be scanned. You'll be asked to lie down on the padded table. Then the technologist will position you inside the magnet so that the appropriate part of your body is ready to be scanned. During the exam, you will be able to talk with the technologist conducting the exam by means of an intercom and they will be able to watch you through a glass window and cameras in the room. You may hear very loud clanking and thumping sounds that the machine makes as the technologists adjust the radio frequencies and other controls. These sounds are completely normal. Sometimes, a radiologist, nurse or technologist may come into the scanning room for an injection. At that time, a liquid contrast agent will be given that aids in showing the blood vessels and organs. The agent is injected into a vein, usually in the arm. All you have to do during the exam is lie as still as possible. Very active children may require some relaxing medication (sedation) prior to the exam to help them stay still.
After the Procedure:
After completing the exam, some computer analysis may be necessary to obtain the best possible images. The radiologist will send a report to your doctor after the images have been studied. It is best to ask your doctor for the exam results.
Scheduling:
If you have any questions regarding MRI scheduling, please call (734) 936-4500. Reviewed and Approved: Hero Hussain, MD Peter Liu, MD Ann Cormack 10/2011