Abdominal Ultrasound
Test OverviewAn abdominal
ultrasound takes pictures of the organs and other structures in your upper belly. It uses sound waves to show images on a screen. Areas that can be checked include the: - Abdominal
aorta. This large blood vessel passes down the back of the chest and belly. It supplies blood to the
lower part of the body and the legs.
- Liver. This large organ lies under the rib cage on the right side of the
belly. It makes bile (a substance that helps digest fat). It also stores
sugars and breaks down many of the body's waste products.
- Gallbladder. This small organ is right under the liver. It stores bile. When you eat, the gallbladder
contracts to send bile to the bowels (intestines). The bile helps your body digest food and
absorb vitamins that dissolve in fat.
- Spleen. This organ helps fight infection. It also filters old red blood
cells. The spleen sits to the left of the stomach, just behind the lower
left ribs.
- Pancreas. This gland is in the upper belly. It makes
enzymes that help digest food. The digestive enzymes
then move into the bowels. The pancreas also releases
insulin into the bloodstream. Insulin helps the body
use sugars for energy.
- Kidneys. This pair of organs is in the upper part of your belly, but toward your back. The kidneys remove wastes from the blood. They also make urine.
If your doctor needs more details about a specific organ in the upper part of your belly, you may get a special ultrasound, such as a kidney ultrasound. If you need the structures and organs in
your lower belly checked, you will get a pelvic ultrasound. Why It Is DoneAbdominal ultrasound is done to: - Find the cause of belly
pain.
- Find, measure, or monitor an
aneurysm in the aorta. An aneurysm may cause a large,
pulsing lump in the belly.
- Check the size, shape, and position of
the liver. It may also check for
problems of the liver. These include jaundice, cirrhosis, or fatty
liver. This test may be done to follow up after liver function tests.
- Look for
gallstones, inflammation of the gallbladder, or blocked bile ducts.
- Learn the size of an
enlarged spleen and look for damage or disease.
- Find problems
with the pancreas, such as
a tumor.
- Look for blocked urine flow in a kidney. If needed, a kidney
ultrasound can find out the size of the kidneys, detect a mass, or detect fluid surrounding the kidneys. It can also look for causes of bladder infections that won't go away. Or it can check how the kidneys are doing after a transplant.
- Find out if a mass in a belly organ is a solid tumor or a fluid-filled
cyst.
- Guide the placement of a needle or other tool
during a
biopsy.
- Look for fluid buildup in the
belly cavity. This problem is called ascites. An ultrasound also may be done to guide the
needle during a paracentesis. This is a procedure to remove fluid from the belly cavity.
How To PrepareTell your doctor if you have had a
barium enema or upper GI
(gastrointestinal) tests within the past 2 days. Barium that stays in the
intestines can affect the results of the ultrasound. You may need to prepare in other ways too. It depends on what test you are having. For example: - If you are having your liver, gallbladder,
spleen, and pancreas checked, you may need to eat a fat-free meal on the evening
before the test. Then you may need to avoid eating for 8 to 12 hours before the
test.
- For a test of the kidneys, you may be asked to drink 4 to 6 glasses of liquid about an hour before the test. This is to fill your bladder. You may need
to avoid eating for 8 to 12 hours before the test to avoid gas buildup in the
intestines. Gas could affect the results of the kidney ultrasound.
- If you are having your aorta checked, you
may need to avoid eating for 8 to 12 hours before the test.
How It Is DoneThe test is done by a radiologist. This is a doctor who
has special training to perform and interpret imaging tests. Sometimes an ultrasound technologist (sonographer) will do the test. In that case, a radiologist will supervise. The test is done in an ultrasound room in a hospital or doctor's office. You may need to take off your jewelry. You may also need to take off all or most of your clothes. It depends on which area is being examined. You will be given a cloth or
paper to cover yourself during the test. During the testYou will lie on your back
(or on your side) on a padded exam table. Warmed gel will be spread on your
belly or back to help the sound waves work best. A small handheld device (transducer) is pressed against your belly. You may be asked to change positions so more scans can
be done. For a kidney ultrasound, you may be asked to lie on your
stomach. You need to lie very still while the test is
being done. You may be asked to take a breath and hold it for several seconds
during the test. This lets the person doing the test see organs and structures more clearly. The test usually
takes 30 to 60 minutes. After the testYou may be asked to wait until the radiologist has
reviewed the images. He or she may want to take more views
of some areas of your belly. How It Feels The gel may feel cold when it is put on
your skin. But the gel may be warmed to body temperature first. You will feel
light pressure from the transducer as it passes over your belly. Most people do not feel pain during the test. But if the test is being done to check
damage from a recent injury, the slight pressure of the transducer may be
somewhat painful. You will not hear or feel the sound waves. RisksThere are no known risks from having an abdominal
ultrasound test. ResultsAn abdominal
ultrasound takes pictures of the organs and other structures in your upper belly. It uses sound waves to show images on a screen. Abdominal ultrasoundNormal: | The organs have a normal size, shape, and texture. No abnormal growths are seen. No fluid is in the
belly. |
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The aorta looks
normal. No
aneurysms are seen. | The thickness of the
gallbladder wall is normal. The size of the bile ducts is normal. No
gallstones are seen. | No
kidney stones are seen. The system that drains the kidneys is not blocked. | Abnormal: | An organ looks abnormal. It may be smaller than normal. A growth may press against it or may be seen in an organ. Or fluid may be seen in the belly cavity. These things may be due to inflammation, infection, or other diseases. |
---|
The aorta is enlarged or an aneurysm is
seen. | The liver looks abnormal. This may
point to liver disease (such as
cirrhosis or cancer). | The walls of the gallbladder are
thickened, or fluid is found around the gallbladder. These may point to
inflammation. The bile ducts may be enlarged. Or gallstones may be seen. | The kidneys or the ureters are enlarged because urine does not drain as it should. Kidney stones are seen. (But not all stones
can be seen with ultrasound.) | An area of infection or a fluid-filled
cyst is seen inside an
organ. Or the spleen may be ruptured. | What Affects the TestYou may not be able to
have the test, or the results may not be helpful, if: - Stool, air (or other gas), or
contrast material (such as barium) is in the stomach or
intestines.
- You cannot stay still during the
test.
- You are extremely overweight.
- You have an open or bandaged wound
in the area being viewed.
What To Think About- You may need other tests, such as a
CT scan, to follow
up after the ultrasound. To learn more, see the topic
Computed Tomography (CT) Scan of the Body.
- In rare cases, gallstones may not be found
by ultrasound. Other imaging tests may be done if gallstones are suspected but
not seen by the ultrasound.
- An ultrasound test can't tell if a solid tumor is
cancerous (malignant) or noncancerous (benign). A
biopsy test may be needed if a tumor is found. Ultrasound
may be used during the biopsy. It helps guide the placement of the
needle.
- Ultrasound costs less than other tests that take pictures of the organs in the belly. But for some problems, such as
masses in the belly or an injury, a CT scan or MRI scan may be the better option. Your doctor may also suggest those tests if ultrasound results are normal but
you still have belly pain.
ReferencesOther Works Consulted- 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 Specialist Medical ReviewerHoward Schaff, MD - Diagnostic Radiology Current as ofOctober 14, 2016 Current as of:
October 14, 2016 Last modified on: 8 September 2017
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