THE MEDICAL IMAGING EXPERIENCE
INFORMATION FOR THE PATIENT
MAGNETIC RESONANCE IMAGING of the HEAD

WHAT IS IT?
Magnetic Resonance Imaging (MRI) is accomplished using a large magnetic field that causes the hydrogen atoms in your body to release radio waves called signals. These radio signals are collected by antenna, much like your TV or radio at home. The MRI computer collects trillions of signals during the MRI procedure and after computer processing, displays the signal information in the form of a picture.

WHAT WILL HAPPEN TO ME?
The MRI technologist will help you lie down on a long narrow table. Special radio antenna that capture signal information to make the pictures, are placed around your head. You will be given ear plugs to wear during the exam, then you will be moved into the center of the big magnet which looks like a large cylinder. When the exam begins, you will feel some vibrations and will hear loud thumping noises. The thumping noises will start and stop and change frequency, but this is normal.

WHAT IF I'M CLAUSTROPHOBIC?
If you are apprehensive about having an MRI or have experienced episodes of claustrophobia in the past, we recommend that you ask your doctor to give you a prescription for something to relax you. This can be filled at the pharmacy of your choice and be taken about and hour prior to your exam. It would be best to have someone drive you to your exam as the medication will alter the awareness of your surroundings.

HOW LONG WILL THIS TEST TAKE?
The MRI head exam can take anywhere from 20 minutes to 40 minutes, depending on the number of images needed to complete the exam. It takes this length of time to allow the computer to collect enough signals and process the signal information into pictures.

WHAT WILL I FEEL -- WILL IT HURT?
You will need to lie perfectly still for most of the test so that the best picture can be made. Lying in one place can become uncomfortable, but it is very important not to move. Occasionally, it is necessary to give an injection to outline the blood vessels in your head.

WHAT WILL THE MRI TEST SHOW?
The picture shows the various tissues in your head including the brain, veins and arteries, etc., in great detail. By looking for unusual patterns in these pictures, the doctor can see any problem areas.

HOW DO I GET READY?
Very little preparation is needed for MRI tests. You will need to wear a hospital gown since any metal such as snaps, zippers and hooks can interfere with the picture. Also, jewelry, hair pins, wallets, keys, etc., must be removed before entering the magnet room. The MRI technologist will assist you in preparing for the MRI test to ensure that all metal has been removed. The MRI technologist will ask you questions about your medical history that will help in completing your MRI test.
 

Reviewed: March 2005