First, the MRI scanner is quite loud.  To help with this you will be given ear plugs and/or a pair of headphones.  An intercom system will let you speak with the technologist during the exam, but this is best done every 3-4 minutes during the breaks between scans.

The second thing to be aware of is that you will need to be as still as you can while the MRI scanner is running.  Motion during a scan will cause the pictures to be blurred and make them difficult to interpret. Blurry scans may need to be repeated, which adds time to the exam.  You will be allowed to make small, subtle movements during the breaks, but for the most part you will need to be very still.  For this reason the MRI Technologist will try to position you in the most comfortable way possible that still allows the scans to be done correctly.

For most patients, having an MRI is a very comfortable experience. Many patients are actually able to fall asleep during the exam.  Make sure to tell the Technologist if there is any way they can make you more comfortable.

Hydrogen atoms are present in large amounts in both water and fat in the body.  These hydrogen atoms can be manipulated by using the magnet and radio frequency pulses so that they give off a radio frequency signal of their own.  This signal is then detected by a coil (which acts like an antenna) placed near the area being scanned. 

The signals received by the coil are then processed to create an image.  Because different tissues, such as bone, tendon, muscle, and cartilage each have a different amount of hydrogen present, extremely detailed images of the anatomy and pathology are able to be produced.  Modern MRI machines, like the Siemens Aera 1.5T used in our office, are able to calculate the location of structures down to fractions of a millimeter. 

There are a few things that may be helpful to know ahead of time.  You will need to remove most jewelry (especially piercings) before your exam.  Metal buttons or clips in clothing may need to be removed as well, depending on what part of your body we are scanning, so you may want to dress accordingly or bring clothes (such as shorts) to change into.  We will provide shorts and/or a T-shirt if needed.

However, depending on the type of metal and where it’s located it could be quite dangerous, so you will be asked to fill out a questionnaire before having your MRI.  Certain implants, such as Pacemakers or clips used to treat brain aneurysms, can have very severe and dangerous reactions in the magnet, so patients with these implants should not have an MRI.  Other implants, such as total joint replacements and plates or screws used to treat fractures are usually safe.

The MRI Technologist will review your questionnaire and medical history to insure you are safe prior to entering the MRI room for your exam.