What is it?

An abdominal ultrasound uses reflected sound waves to produce a picture of the organs and blood vessels in the upper belly. These include your liver, gallbladder, spleen, pancreas, kidneys, and major blood vessels like the aorta. The sound waves create a picture on a video monitor.

Why is this test done?

An ultrasound can be done to:

• Find out what's causing belly pain—a gallstone, for example.
• Look at a lump or mass that was found in a prior exam and, in some cases, tell what it is.
• Check for problems in the liver and kidneys.
• Look for changes in an aortic aneurysm, a bulging section in the wall of the large artery that carries blood out of the heart.
• Find fluid in the belly.
• Guide needles or other medical instruments in treatment.

How can you prepare for the test?

Depending on the part of your belly your doctor will be looking at, you may need to eat a fat-free meal the night before your test. Or you may need to avoid eating for 4 to 12 hours before the test. Your doctor will tell you what to do.

How is the test done?

• You lie down on your back or your side on an exam table.
• The doctor or technologist spreads some warm gel on your belly to improve the transmission of the sound waves. A small hand-held unit called a transducer is pressed against your belly and is moved back and forth. A picture of the organs and blood vessels can be seen on a video monitor.
• You need to lie still. You may be asked to take a breath and hold it for several seconds during the scanning.

How does having an abdominal ultrasound feel?

Most people do not feel pain during the test. If your belly hurts already from an injury or illness, the slight pressure from the transducer may be somewhat painful. You will not hear or feel the sound waves.

How long does the test take?

• The test will take about 30 minutes.
• You may be asked to wait until the radiologist has reviewed the scan. He or she may want to do more ultrasound views of some areas of your belly.

What happens after the test?

• You will probably be able to go home right away.
• You can go back to your usual activities right away.