Understanding MRI
Your doctor has referred you to the MRI Centers for an MRI scan. This information is designed to explain the process of MRI scanning and help you understand what to expect. Magnetic Resonance Imaging (MRI) is a highly advanced and safe imaging method used to achieve pictures of the internal structures of the body. MRI utilizes magnetic fields and radio waves to produce the images. MRI can illustrate the differences between healthy and diseased tissue. In some cases, MRI can simplify the need for extensive testing. Another advantage is that MRI can actually “see through” bone, enabling very finely detailed images of soft tissue. It also offers imaging in any plane for three-dimensional viewing.
The MRI Scanning Process
For most scans, no advance preparation is required. If you are scheduled for an abdominal or a pelvic scan, do not eat or drink for 4 hours prior to your appointment. You will be asked to change into a gown to avoid interference from metal zippers, snaps or buckles. A private locker will be provided for you since the following items cannot be taken into the scanning room:
- Jewelry/Watches
- Coins
- Hairpins/Clips
- Credit Cards
- Dentures
- Keys
- Glasses
- Metal Objects
- Hearing Aids
Patients who have metal within the eye, brain or spinal cord generally cannot be imaged. If you have ever had metal fragments in your eyes, an X-ray of the eyes may be necessary before an MRI can be done. If you have this history, please contact the MRI Centers before your scheduled appointment. Please remember that any metal inside your body (such as cardiac pacemakers or intracranial aneurysm clips) can be affected by the MRI magnet. You must inform the MRI Centers’ personnel if you have ANY metal objects implanted in your body. The same precautions and procedures will apply to anyone who may accompany you in the MRI scanning room.
For some studies an injection of contrast will be given before or during the scan. Extreme rare allergic reactions can occur with any medication, however contrast used for MRI is generally very safe.
The MRI process is painless and takes from 30 to 60 minutes, depending on the specific study your doctor has requested. You will lie on a comfortable table which will move into the center of a large cylinder shaped magnet. The patient compartment is open at both ends, ventilated, well-lighted, and there is an intercom so our staff can monitor you during the entire scan. A small number of patients who suffer from claustrophobia may tend to feel “closed in” or be bothered by the knocking noise they hear during the scan. Let us know if you feel anxious or ill so we can help make you more comfortable or discontinue the test if you so desire. For the MRI study, several sets of scans are required. Each set takes 2 to 10 minutes, during which time it is necessary to remain as motionless as possible. Throughout your scan we are able to hear, see and speak to you. As the study is performed, you will hear a tapping sound; otherwise, there is no sensation during the scan so you can relax and may even go to sleep. Following your scan you can resume normal activities and should not experience any after effects. The MRI Centers’ radiologists will interpret your scan and promptly report the results to your doctor, who will then discuss the findings with you.
Special Concerns About MRI
The powerful magnetic field from the MRI scanner is what allows us to obtain such clearly defined images. However, the force is also strong enough to erase credit cards or disturb metallic objects in the body. For this reason, patients with cardiac pacemakers or intracranial aneurysm clips are NOT candidates for MRI scanning. Other metallic devices (such as prosthetic heart valves and joint replacements) are usually safe for MRI exams, but the MRI Centers’ staff should be made aware of them to check if they are MRI compatible. Also, pregnant women should consult with their physicians about the advisability of an MRI scan. Our open architecture scanner (location #2) now offers greater flexibility in size and weight parameters as well as a less confining environment for patients who tend to be claustrophobic.