Magnetic Resonance Imaging (MRI) of the Abdomen
Magnetic Resonance Imaging (MRI) of the AbdomenSkip to the navigationTest OverviewMagnetic resonance imaging (MRI) is a test
done with a large machine that uses a magnetic field and pulses of radio wave
energy to make pictures of organs and structures inside the belly. In many
cases MRI gives information about structures in the body that cannot be seen as
well with an
X-ray,
ultrasound, or
CT scan. For an MRI test, you are placed
inside the magnet so that your belly is inside the strong magnetic field. MRI
can find changes in the structure of organs or other tissues. It also can find
tissue damage or disease, such as infection or a tumor. Pictures from an MRI
scan are digital images that can be saved and stored on a computer for further
study. The images also can be reviewed remotely, such as in a clinic or an
operating room. Photographs or films of selected pictures can also be
made. In some cases, contrast material may be used during the MRI scan to
show certain structures more clearly in the pictures. The contrast material may
be used to check blood flow, find some types of tumors, and show areas of
inflammation or infection. Although MRI is a safe and valuable
test for looking at structures and organs inside the body, it is more expensive
than other imaging methods and may not be available in all medical
centers. You may be able to have an MRI with an open machine that doesn't enclose your entire body. But open MRI machines aren't available everywhere. The pictures from an open MRI may not be as good as those from a standard MRI machine. Why It Is DoneMagnetic resonance imaging (MRI) of the
abdomen is done to: - Find problems or tumors in the
abdominal organs and tissues. In some cases, MRI can
tell if a tumor is noncancerous (benign) or cancerous
(malignant).
- Check lower abdominal and pelvic organs for tumors,
bleeding, or problems present since birth (congenital
abnormalities).
- Find a blocked tube or stones in the tube that
carry
bile from the liver to the gallbladder (bile
duct).
- Check organs and blood vessels prior to organ transplantation or
surgery.
How To PrepareBefore your MRI test, tell your doctor
and the MRI technologist if you: - Are allergic to any medicines. The contrast
material used for MRI does not contain iodine. If you know that you are allergic to the contrast material used for the MRI, tell your doctor before having another test.
- Are or might be pregnant.
- Have any metal implanted in your body. This helps your doctor know if the test is safe for you. Tell your doctor if you have:
- Heart and blood vessel devices such as a coronary artery stent, pacemaker, ICD (implantable cardioverter-defibrillator), or metal heart valve.
- Metal pins, clips, or metal parts in your body, including artificial limbs and dental work or braces.
- Any other implanted medical device, such as a medicine infusion pump or a cochlear implant.
- Cosmetic metal implants, such as in your ears, or tattooed eyeliner.
- Had recent surgery on a blood vessel. In some
cases, you may not be able to have the MRI test.
- Have an
intrauterine device (IUD) in place. An IUD may prevent
you from having the MRI test done.
- Become very nervous in confined
spaces. You need to lie very still inside the MRI magnet, so you may need
medicine to help you relax. Or you may be able to have the test done with open
MRI equipment. It is not as confining as standard MRI machines.
- Have any other health conditions, such as kidney problems or
sickle cell anemia, that may prevent you from having
an MRI using contrast material.
- Wear any medicine patches. The MRI may cause a burn at the patch
site.
For some abdominal MRI tests, you may be asked to not eat
or drink before the test. You may be asked to sign a consent form. Talk to your doctor about any concerns you have regarding the need for
the test, its risks, how it will be done, or what the results will mean. To
help you understand the importance of this test, fill out the
medical test information form(What is a PDF document?). You may need to arrange for someone to
drive you home after the test, if you are given a medicine (sedative) to help you relax. How It Is DoneBefore the testA magnetic resonance imaging (MRI) test
is usually done by an MRI technologist. The resulting pictures are usually
interpreted by a
radiologist. But some other types of doctors can also
interpret an MRI scan. You will need to remove all metal objects
(such as hearing aids, dentures, jewelry, watches, and hairpins) from your body
because these objects may be attracted to the powerful magnet used for the
test. You will need to take off all or most of your clothes,
depending on which area is examined (you may be allowed to keep on your
underwear if it is not in the way). You will be given a gown to use during the
test. If you are allowed to keep some of your clothes on, you should empty your
pockets of any coins and cards (such as credit cards or ATM cards) with scanner
strips on them because the MRI magnet may erase the information on the
cards. During the testDuring the test, you will lie on your back on a table that
is part of the MRI scanner. Your head, chest, and arms may be held with straps
to help you remain still. The table will slide into the space that contains the
magnet. A device called a coil may be placed over or wrapped around the area to
be scanned. A special belt strap may be used to sense your breathing. The belt
triggers the machine to take the scan at the right time. Some
people feel nervous (claustrophobic) inside the MRI magnet. If feeling nervous
keeps you from lying still, you can be given a medicine (sedative) to help you
relax. You may be able to have an MRI with an open machine that doesn't enclose your entire body. But open MRI machines aren't available everywhere. The pictures from an open MRI may not be as good as those from a standard MRI machine. Inside the scanner, you will hear a fan and feel
air moving. You may also hear tapping or snapping noises as the MRI scans are
taken. You may be given earplugs or headphones with music to reduce the noise.
It is very important to hold completely still while the scan is being done. You
may be asked to hold your breath for short periods of time. You
may be given a medicine, such as glucagon, to slow bowel movements for some MRI
tests. During the test, you may be alone in the scanner room. But
the technologist will watch you through a window. You will be able to talk with
the technologist through a two-way intercom. If contrast material
is needed, the technologist will put it in an
IV in your arm or hand. The material may be given over
1 to 2 minutes. Then more MRI scans are done. An MRI test usually
takes 30 to 60 minutes but can take as long as 2 hours. How It FeelsYou won't have pain from the magnetic
field or radio waves used for the MRI test. The table you lie on may feel hard
and the room may be cool. You may be tired or sore from lying in one position
for a long time. If a contrast material is used, you may feel some
coolness when it is put into your IV. In rare cases,
you may feel: - A tingling feeling in the mouth if you have
metal dental fillings.
- Warmth in the area being examined. This is
normal. Tell the technologist if you have nausea, vomiting, headache,
dizziness, pain, burning, or breathing problems.
RisksThere are no known harmful effects from the
strong magnetic field used for MRI. But the magnet is very powerful. The magnet
may affect pacemakers, artificial limbs, and other medical devices that contain
iron. The magnet will stop a watch that is close to the magnet. Any loose metal
object has the risk of causing damage if it gets pulled toward the strong
magnet. Metal parts in the eyes can damage the
retina. If you may have metal fragments in the eye, an
X-ray of the eyes may be done before the MRI. If metal is found, the MRI will
not be done. Iron pigments in tattoos or tattooed eyeliner can
cause skin or eye irritation. An MRI can cause a burn with some
medicine patches. Be sure to tell your doctor if you are wearing a
patch. There is a slight chance of an
allergic reaction if contrast material is used during
the MRI. But most reactions are mild and can be treated using medicine.
Contrast material that contains gadolinium may cause a serious problem (called
nephrogenic systemic fibrosis) in people with
kidney failure. If you have decreased kidney function
or serious kidney disease, tell your doctor before having an MRI scan. There also is a slight risk of an infection at the IV site if contrast
material was used. If you breastfeed and are concerned about whether the dye used in this test is safe, talk to your doctor. Most experts believe that very little dye passes into breast milk and even less is passed on to the baby. But if you prefer, you can store some of your breast milk ahead of time and use it for a day or two after the test. If you are pregnant, be sure to tell your doctor. The contrast material that contains gadolinium could be harmful to your baby. ResultsMagnetic resonance imaging (MRI) is a test done with a large machine that uses a magnetic
field and pulses of radio wave energy to make pictures of organs and structures
inside the belly. The
radiologist may discuss initial results of the MRI
with you right after the test. Complete results are usually available for your
doctor in 1 to 2 days. An MRI scan can sometimes find a problem in
a tissue or an organ that is not seen by
X-ray,
ultrasound, or
CT scan, even when the size and shape of the tissue or
organ looks normal. Magnetic resonance imaging (MRI) of the abdomen Normal: | The organs and blood vessels are normal in
size, shape, and location. |
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No abnormal growths, such as tumors, are
present. | No blockage is found in the ducts draining
the liver, gallbladder, or pancreas. | No blockage is found in the tubes (ureters) that lead out of the kidneys. | No bleeding, abnormal collections of fluid,
blockage in the flow of blood, or bulges in the blood vessels (aneurysms) are present. | No signs of inflammation or infection are
present. | Abnormal: | An organ is too large, too small, or in
the wrong place. The MRI also may show areas of scarring or injury. |
---|
Growths are found, such as tumors that
could be either benign or cancerous. Signs of infection may be
present. | A collection of fluid is present, which
could mean you have internal bleeding or an infection. | A bulge in the wall of a blood vessel
(aneurysm) is present. Blockage in or narrowing of a blood vessel also may be
found. | Blockage is present in the
bile ducts. Reasons for the blockage may include a
gallstone, tumor, infection, or inflammation. | Blockage is present in the tubes leading
from the kidneys (ureters). Reasons for the blockage may include a kidney
stone, tumor, infection, or inflammation. | What Affects the TestReasons you may not be able to
have the test or why the results may not be helpful include: - Medical devices that use electronics, such as a pacemaker
or medicine infusion pump. The MRI magnet may cause problems with these
devices.
- Medical devices that contain metal, which can make some of
the detailed MRI pictures blurry. This may prevent your doctor from seeing the
organ that is being looked at. For example, an
intrauterine device (IUD) that contains metal may
prevent your doctor from seeing the uterus clearly.
- If you are not
able to remain still during the test.
- Obesity. A person who is very overweight may not fit
into standard MRI machines.
What To Think About- Sometimes your MRI test
results may be different than those from CT, ultrasound, or X-ray tests because
the MRI scan is more specific.
- An abdominal CT scan or
abdominal ultrasound is generally done before an MRI
of the abdomen. Another test that may be done before or after an MRI of the
abdomen is called endoscopic retrograde cholangiopancreatography (ERCP).
- Open MRI machines are now made so that the magnet does not
completely surround you. Open MRI is useful for people who are claustrophobic
or obese. But these machines are not available everywhere. Also, these machines
may not be able to do all the studies needed to check for
problems.
- Magnetic resonance angiogram (MRA) is a
special MRI method that studies blood vessels and blood flow. To learn more, see the topic
Magnetic Resonance Angiogram (MRA).
ReferencesOther Works Consulted- Chernecky CC, Berger BJ (2008). Laboratory Tests and Diagnostic Procedures, 5th ed. St. Louis: Saunders.
- Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.
- Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier.
CreditsByHealthwise Staff Primary Medical ReviewerKathleen Romito, MD - Family Medicine E. Gregory Thompson, MD - Internal Medicine Adam Husney, MD - Family Medicine Martin J. Gabica, MD - Family Medicine Specialist Medical ReviewerHoward Schaff, MD - Diagnostic Radiology Current as ofNovember 28, 2016 Current as of:
November 28, 2016 Last modified on: 8 September 2017
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