What is MRI?
Magnetic Resonance Imaging is a way to visualize anatomic structures within the body by using radio waves and a magnet. Exposing the body to a strong magnetic field causes all of the hydrogen atoms to be in alignment. The machine then sends a high frequency radio wave, which causes these hydrogen atoms to "resonate" or send back a signal giving detailed information about body structures. The image resolution is high detail and is useful for many parts of the body.
What to Expect During MRI?
You will lie on a bed and the technologist will position you comfortably. Headphones or earplugs will be placed over your ears. The machine can be very loud. Music will be provided through the headphones if you desire. The scanning bed will enter a large cylinder that is open on both ends and you will be kept in constant communication with the technologist because he/she will be able to hear and see you at all times. Depending on the scan you are having, the exam will take 30 minutes to 2 hours. Please lie still and relax, as movement will impair the scan.
What if I'm afraid of closed in spaces?
Claustrophobia is a common condition that can cause difficulty during an MRI exam. If you suspect that you may have a problem, please contact your doctor so that he/she may prescribe a medication that will help you relax and relieve anxiety.
Is MRI painful?
The MRI exam is not painful, but you may be given an intravenous injection during your scan to allow for better visualization of certain body structures. The contrast injection may be slightly painful, but the medication does not produce any sensations.
What are some uses of MRI?
MRI gives unparallel quality in imaging the brain, spine, bones and joints. The clarity is superior and enables the physician to diagnose very small abnormalities.
Is MRI safe?
Because MRI uses no X-rays, it presents no apparent health hazards. If you are pregnant or nursing, please consult your doctor before having the exam.
EXAM PREPARATION
How do I prepare for an MRI?
Wear comfortable clothing with no metallic buttons, zippers, or hooks or you will be asked to change into a gown. You may be asked to not eat or drink two hours before the exam if it is ordered "with contrast." You will need to remove all metal objects from your body. Glasses, dentures, hearing aids, jewelry, credit cards and barrettes will need to be removed prior to the exam.
Who can have an MRI?
Anyone can have a MRI except those with the following conditions: Heart pacemaker, history of metal in your body (except dental work), artificial heart valves, previous brain aneurysm surgery, and severe claustrophobia. If you fall under any one of these categories, please consult with the MRI technologist prior to the exam.
MRA
What is MRA?
Magnetic Resonance Angiography is an imaging method used to visualize certain blood vessels in the body. It is used as an alternative to angiography, which requires needles and catheters to be inserted into the vessels. MRA is painless and is used to visualize blood flow in the head, neck, aortic arch, kidneys and femoral arteries.
How long does the exam last?
Most MRAs last anywhere from 45 minutes to two hours depending on the exam. It is very important that you remain absolutely still during the entire exam.
Is there any preparation involved?
There is no preparation needed for a MRA.
Why is MRA useful?
It provides a high quality tool for the radiologist to make a diagnosis of vessel disease. It shows abnormalities, such as stenosis (narrowing of a vessel) or aneurysm. It is a safe alternative to angiography, which is a surgical way to examine the blood vessels using iodine contrast.
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