Abdominal Sonography

Abdominal Sonography examines the organs and arteries of the upper abdomen using ultrasound technology. Abdominal Sonography is used to examine and evaluate:

• Abdominal Aorta
• Appendix
• Gallbladder
• Kidney
• Liver
• Pancreas
• Spleen

The reflected sound waves are returned as echoes which are then recorded and displayed as a real-time visual image. Abdominal sonography is a noninvasive imaging test that helps physicians diagnose and treat medical conditions. An abdominal ultrasound documents the abdominal organs and other structures in the upper abdomen.

Organs and structures in the lower abdomen are examined using a Pelvic Ultrasound.

Abdominal ultrasounds are typically preformed using a standard ultrasound, but if blood flow is also being evaluated, doppler ultrasound is used instead of, or in addition to, a standard ultrasound.

Abdominal ultrasound is done to:

• Find the cause of abdominal pain.
• Find, measure, or monitor an aneurysmin the aorta. An aneurysm may cause a large, pulsing lump in the abdomen.
• Check the size, shape, and position of the liver. An ultrasound may be done to evaluate jaundiceand other problems of the liver, including liver masses,cirrhosis, fat deposits in the liver (called fatty liver), or abnormal liver function tests.
• Detect gallstones, inflammation of the gallbladder (cholecystitis), or blocked bile ducts. See a picture of a gallstone.
• Learn the size of an enlarged spleen and look for damage or disease.
• Find problems with the pancreas, such as a pancreatic tumor.
• Look for blocked urine flow in a kidney. A kidney ultrasound may also be done to find out the size of the kidneys, detect kidney masses, detect fluid surrounding the kidneys, investigate causes for recurring urinary tract infections, or check the condition of transplanted kidneys.
• Find out whether a mass in any of the abdominal organs (such as the liver) is a solid tumor or a simple fluid-filled cyst.
• Guide the placement of a needle or other instrument during a biopsy.
• Look for fluid buildup in the abdominal cavity (ascites). An ultrasound also may be done to guide the needle during a procedure to remove fluid from the abdominal cavity (paracentesis).

How is abdominal ultrasound done?

An abdominal ultrasound uses a handheld probe called a transducer that sends out ultrasonic sound waves at a frequency too high to be heard. When the transducer is placed on the abdomen at certain locations and angles, the ultrasonic sound waves move through the skin and other body tissues to the organs and structures of the abdomen. The sound waves bounce off the organs like an echo and return to the transducer. The transducer picks up the reflected waves, which are then converted into an electronic picture of the organs.

Different types of body tissues affect the speed at which sound waves travel. Sound travels the fastest through bone tissue, and moves most slowly through air. The speed at which the sound waves are returned to the transducer, as well as how much of the sound wave returns, is translated by the transducer as different types of tissue.

Prior to the procedure, clear, water-based gel is applied to the skin to allow for smooth movement of the transducer over the skin and to eliminate air between the skin and the transducer.

By using an additional mode of ultrasound technology during an ultrasound procedure, blood flow within the abdomen can be assessed. An ultrasound transducer capable of assessing blood flow contains a Doppler probe. The Doppler probe within the transducer evaluates the velocity and direction of blood flow in the vessel by making the sound waves audible. The degree of loudness of the audible sound waves indicates the rate of blood flow within a blood vessel. Absence or faintness of these sounds may indicate an obstruction of blood flow.

Ultrasound may be safely used during pregnancy or in the presence of allergies to contrast dye, because no radiation or contrast dyes are used.

Other related procedures that may be performed to evaluate the abdomen include abdominal X-rays, computed tomography (CT scan) of the abdomen, and abdominal angiogram. Please see these procedures for more information.