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Magnetic Resonance Imaging (MRI)
An MRI exam is a special way of looking inside of your body. It is different than an X-ray. It uses a magnetic field and radio waves to create the pictures. During the test, a contrast agent ("dye") may be given. It makes certain parts of your body appear brighter on the pictures.
The exam time depends upon the area to be scanned and the information needed by your doctors. Most exams last about 45 to 60 minutes. The MRI is done in the Radiology (X-ray) Department. Northwestern offers the option of three locations.
Before the Test
Please tell your doctor if you might be pregnant, are trying to get pregnant or are breastfeeding.
Dialysis patients should try to schedule their MRI exam just before their dialysis treatment. This helps rid the body of any contrast dye used during the MRI exam. Every MRI patient needs to be screened to ensure that certain safeguards are in place. If you have any metal inside of your body, please tell your doctor before the exam. This may include:
- pacemaker
- aneurysm clip
- ear or eye implant
- joint or bone rods or clips
- metal plate
- bullets or shrapnel
It is also helpful to talk with your doctor if you:
- cannot lie flat (for about an hour)
- have claustrophobia (uncomfortable with closed-in spaces).
Please ask your doctor if you need to make any changes in your diet before this exam. Otherwise, there is no special preparation for this test.
Day of the Test
Arriving at the Hospital
On the day of the test, plan to arrive 30 minutes before your test time. Also, be sure to bring:
- your doctor's written order for the test
- insurance card
- Medicare card (Medicare patients only)
If plans were made to give you any medicine to help you relax, you will also need a responsible adult to take you home.
Upon arrival, you are asked to complete an MRI Safety Questionnaire and a medical history form.
Preparing for the Test
Prior to the test, you are taken to a locker room to change into a hospital gown and store your belongings. It is important that you remove all metal from your body including jewelry, credit cards, keys and dentures. The nurse then reviews your completed forms with you. An IV (into the vein) line is started in your arm or hand.
During the Test
- Once you are taken into the exam room, you are introduced to the technologist (tech) and nurse doing the test. They can answer any questions you may have.
- You will be asked to lie on a table attached to the MRI machine. The nurse and tech help position you comfortably on the exam table.
- You will be given a hand held "bulb" to help you contact the tech during the test as needed. Earplugs will be provided.
- If medicine to relax you is ordered, it is injected into the IV at this time. You may be given an IV contrast agent (gadalinium dye) during the test.
- As the dye is injected, you may feel warm, flushed or you might notice a metallic taste in your mouth. This is normal. However, please notify the staff right away if you have shortness of breath, hives or itching.
- Your body and the machine are "lined up" so that the proper area of your body can be examined. Then the table moves so that you are in the center of the machine. The tech keeps in contact with you throughout the exam.
- During the MRI scanning, you will hear a loud drumming noise. It is very important that you lie still and follow the staff 's instructions.
- Between scans, the drumming noise stops.
- You may be asked to hold your breath several times during the test.
- When the exam is over, you will be assisted off the exam table.
After the Test
- If relaxing medicine was given, you must remain in the department until the medicine wears off.
- Unless told otherwise, you may resume your normal activities and diet after the exam. It is helpful to drink extra fluids if a contrast agent was given. The contrast agent does not discolor your urine.
- Most often, initial findings are sent to your doctor within 48 hours. A full report follows in about five business days.
Contact
MRI Department
(312) 926-9000
Review Date: 01/04
