What is an MRI scan?

Magnetic resonance imaging (MRI) looks inside the body using magnetism and radio waves instead of an x-ray. These  scans produce extremely clear pictures of whatever body parts are being scanned at the time, including but not limited to head, spine, arms, and bones.  An MRI scanner has a strong magnet and radio transmitter to receive information from your body and produce soft-tissue images. These images are used to distinguish normal, healthy tissue from pathologic tissue.

Your doctor may require a contrast-agent to be given intravenously to assist visualization of certain structures in your body.  A contrast-agent may or may not be used, depending on what information is needed.

Preparing for an MRI

There are no special preparations for an MRI unless your doctor has specific instructions for you. You will need to complete a safety screening form and answer medical history questions.

Loose clothing without zippers or metallic parts are preferable. You will need to remove any metallic objects, such as hairpins, jewelry, watches, glasses and your wallet. Credit cards and other cards with magnetic in-coding can be completely erased by the MRI.

What happens during an MRI scan?

The technologist will position you on a special table, after you have removed all metal objects. Your head will be placed in a padded plastic cradle or on a pillow, and the table will slide into the scanner. You and the technologist will be able to communicate during the scan.

You will need to hold very still and relax during the procedure, and sometimes asked to hold your breath up to 30 seconds in some instances. Any movement of your head, back, or even talking will seriously blur the pictures. You will hear loud, repeating thumping noises during the scan. When it stops you will still need to keep your position and not move.

This procedure will usually be repeated several times during the 15 to 30 minutes needed to complete the scan.

Important: Precautions

MR is a non-invasive, safe test. Since it works with strong magnet and radio waves, you need to let your technician know if you or anyone accompanying you has the following:

Hearing aid

Any metallic external or internal object, fragment, or foreign body

Aneurysm clip(s)

Cardiac pacemaker

Implanted cardioverter defibrillator

Electronic implant or device

Magnetically activated implant or device

Neurostimulation system

Spinal cord stimulator

Cochlear implant or implanted hearing aid

Artificial prosthetic limb or implant

Any metallic substance can affect the quality of the diagnostic images if brought into the magnet area. Discomfort or even injury is possible if placed in the magnetic field.

Also, please notify the technologist if you are pregnant.

Finding out the results

The radiologist will interpret your exam and report his findings to your doctor. Your doctor will discuss the results with you and explain what they mean in relation to your health. Results cannot be given directly to the patient or the family at the time of the scan.