Elliot Imaging Center at Londonderry
Screening and Pre-registration
What can you expect during the exam?
Magnetic Resonance Imaging (MRI) is an advanced medical imaging technique that produces cross-sectional images of the body without the use of X-rays. The images are produced using a large magnet, radio frequency waves and a computer system.
Large Bore Magnetic Resonance Imaging (MRI) uses the same technology as a standard MRI machine but has a larger patient opening. The width of the opening (bore) of the MRI machine is 70 centimeters across and the length of the MRI machine is 125 centimeters long. Siemens has designed this machine to have the same picture quality as a standard MRI machine but in a less confining area. This greatly eases patients who are uncomfortable with confining spaces. Having a larger bore also permits us to perform MRI’s on patient of all sizes while maintaining patient comfort.
The human body contains an abundant amount of water, and those water
molecules (hydrogen atoms) act as tiny magnets. The MRI magnetic
field aligns the molecules and applies a radio wave frequency.
This stimulates the molecules to release energy that transmits
as a signal. The MRI test is very noisy due to gradient pulses
that determine the location of signals within the body. A powerful
antenna collects the signals, which are collected and processed
by powerful computers to generate detailed images from within the
body.
Screening and Pre-registration
It is recommended to pre-register prior to your appointment. This is a simple procedure in which your current information is updated such as insurance, address etc. Click here to complete your pre-registration paperwork, or call 603-663-5663. If you are pre-registered, you may come directly to the MRI Department in Londonderry at your scheduled time. If you are not pre-registered, you will need to go to the Admissions Department at the Elliot Medical Center at Londonderry and register before your appointment.
The MRI patient coordinator will attempt to call you prior to your appointment. This is not the same as pre-registration. The purpose of this call is to ask a few screening questions to make sure you are a candidate for the exam. Certain implants are not safe in a magnetic environment. This phone call is also provided to answer any questions you may have about the MRI exam.
Please wear clothes without any metal zippers, hooks or snaps. These objects can cause a bright or blank spot on the picture. Do not wear hairclips or hairpins. Leave your jewelry at home. If this is not possible, a personal locker will be provided for you. If your MRI is of your head, do not wear eye makeup. Do not bring credit cards, keys or coins into the MRI exam room.
There are many metal implants that are perfectly safe in the MRI environment and MRI poses no known risk to most patients if appropriate safety guidelines are followed. However, for some patients, MRI may be inadvisable. It is very important that you communicate all your implant information when the MRI patient coordinator or technologist screens you.
If you have a cardiac pacemaker or internal defibrillator,
your MRI will be cancelled. These implants are affected
by the magnetic field used in a MRI exam. Hearing
aids must be removed before entering the exam room.
The magnet will cause damage to hearing aids.
Please let the MRI patient coordinator or technologist know if you have:
• Cardiac Pacemaker/ defibrillator
• Aneurysm clips
• Metal plates, pins, or other metallic implants
• Shrapnel from a gunshot wound
• Ever been a metal worker
• Permanent tattoo eyeliner
• Cochlea implant
• TENS unit (dorsal column stimulator)
Also, be sure to tell us if you are pregnant or think you might possibly be pregnant.
If you are scheduled to have a MRCP (a special MRI of the bile ducts), you must fast for 6 hours prior to the exam. For all other examinations, you may eat or drink as usual.
What you can expect during the exam?
The MRI exam itself is painless. The technologist will ask you to
lie down on a cushioned table. A device called a coil will be adjusted
into place. The table is moved into position within the large donut-shaped
magnet. Keep in mind that the part of the body being imaged needs
to be positioned in the center of the magnet. The technologist
will be in contact with you at all times visually and through an
intercom. You will hear a series of repetitive pulsing or knocking
noises. This noise occurs when the images are being taken so it
is particularly important to hold very still. Motion causes the
images to blur and will extend the exam time since it would be
necessary to repeat that sequence. Headphones with music or earplugs
are offered to muffle the loud noises heard during the exam.
Your doctor or the radiologist will determine whether an injection of contrast (dye) is necessary to complete your test. MRI contrast is very different from X-ray contrast. It does not contain Iodine, which many patients are allergic to when having CT scans or IVP exams.
After the MRI exam, you are free to resume your normal daily activities. Soon after the completion of the test, a radiologist will do a careful analysis of all the images. The results will be reported to your personal physician, usually within 24 hours. Your physician will then contact you to discuss your test results.
If you have any questions regarding an upcoming MRI exam, please feel free to call our patient coordinator at 603-552-1477.
