Is an MRI?
magnetic resonance imaging (MRI) is a type of noninvasive test that uses
magnets and radio waves to create images of the inside of the body. The
magnets and radio waves create cross-sectional images of the abdomen, which
allows doctors to check for abnormalities in the tissues and organs without
making an incision.
The technology used in an MRI allows doctors to examine soft
tissues without bones obstructing the view. An MRI uses no radiation and is
considered a safer alternative to a CT scan.
Your doctor may order an abdominal MRI scan if you had abnormal
results from an earlier test such as an X-ray, CT scan, or blood work.
Is an MRI Performed?
Abdominal MRI scans are used for a variety of reasons. Your
doctor will order an MRI if they suspect something is wrong in your abdominal
area but can’t determine what through a physical examination.
Your doctor may want you to undergo an abdominal MRI scan to:
- examine blood flow
- examine your blood vessels
- investigate the cause of pain or swelling
- examine lymph nodes
Are the Risks of an MRI?
There have been no documented side effects from radio waves and
magnetism to date.
Metal objects are not allowed near MRIs because the machine uses
magnets. Let your doctor know if you have any metal implants.
People who are claustrophobic or get nervous in enclosed spaces
may feel uncomfortable in the machine. Your doctor may prescribe anti-anxiety
medication or sedatives to help you relax.
Do I Prepare for an MRI?
Because the MRI uses magnets, it can attract metals. Alert your
doctor if you have any type of metal implant from previous surgeries, such as:
- artificial heart valves
- clips, pins, or screws
Before the test, tell your doctor if you have a pacemaker.
Depending on the type of pacemaker, your doctor may suggest a different
radiological exam, such as an abdominal CT scan. Some pacemaker models can be
reprogrammed before an MRI so they’re not disrupted during the examination.
If your doctor needs images of your colon, you may be required to
use laxatives or enemas before the MRI. You also may need to fast for four to
six hours before the exam.
Your doctor may require the use of a special dye that highlights
areas of concern. This dye (gadolinium) is administered through an IV. While
allergic reactions to the dye are rare, you should alert your doctor of any
concerns before they give you the IV.
Is an MRI Performed?
An MRI machine looks like it could transport you to another
dimension. It has a bench that slowly glides you into a large tube attached to
an opening that looks like a doughnut.
The technician will ask you to lie on your back on the bench and
will give you a blanket or pillow. The technician will control the movement of
the bench using a remote control from another room, and will communicate with
you over a microphone.
The machine will make loud whirring and thumping noises as it takes
images. Many hospitals offer earplugs, televisions, or headphones to help pass
MRI machines are very sensitive to movement, so it’s important
that you stay very still. The technician may also ask you to hold your breathe
for a few seconds as pictures are being
You won’t feel anything during the test. The magnets and radio
frequencies are similar to those on FM radios, and can’t be felt.
The entire process takes 30 to 90 minutes.
Once the test is over, you’re free to drive yourself home and
continue your normal daily activities.
If the images are projected onto film, it can take hours to get
the film developed. It will also take some time for your doctor to review and
interpret the images. More modern machines display images on a computer,
allowing your doctor to view them quickly.
Preliminary results from an abdominal MRI may come within a few
days, but comprehensive results can take a week or more. A radiologist will
examine the images and send a report to your doctor. Your doctor will meet with
you to go over your results.
MRI exams are ordered for many different reasons. Abnormal results
depend on what the test was looking for. Your doctor may order more lab tests
or physical exams before they can establish a diagnosis.