What is magnetic resonance imaging?

Magnetic resonance imaging (MRI) is a technique that produces a very detailed picture of the internal organs and structures of the body without using x-rays. The electromagnetic energy released during this technique is measured and fed into a computer to form an image, which is viewed on a TV monitor.

When is it used?

MRI is especially helpful in diagnosing tumors in the brain and spinal cord, as well as diseases and disorders of the eyes and ears. It can be used to examine joints and soft tissues.

Because MRI uses a large magnet, people with certain metal implants should not have this procedure done. Discuss any concern with your doctor.

How do I prepare for MRI?

No preparation is necessary for MRI unless the doctor gives you special instructions.

What happens during the procedure?

MRI is usually done in a hospital. It takes about 30 minutes and does not require anesthesia.

You will be asked to lie very still, on a table in a small, enclosed tunnel. You may feel a little cramped. The tunnel has a magnet and a radio-wave source. These are connected to a computer and display screen. When the machine is turned on, the computer produces detailed images of the body tissues.

What happens after the procedure?

There are no special steps to take after the procedure unless the doctor gives you instructions.

What are the benefits of this procedure?

The procedure helps the doctor see inside your body, which helps to diagnose your problem.

What are the risks associated with this procedure?

Other than with certain metal implants, there are no known risks, but discuss your concerns with your doctor.

When should I call the doctor?

Call the doctor immediately if:

• You have any change or worsening of pain or symptoms.

Call the doctor during office hours if:

• You have questions about the procedure or its result.

• You want to make another appointment.