The test is performed in a radiology department by a radiologist. You will be asked to lie on your back on the X-ray table. The upper right side of the abdomen is cleansed and a local anesthetic is given. A long, thin, flexible needle is then inserted through the skin into the liver.

With guidance from the fluoroscope (an X-ray machine that projects images onto a TV screen), the bile duct is located and the contrast medium injected. The contrast medium then flows through the ducts and can be seen on the fluoroscopic monitor.

Inform the health care provider if you are pregnant. You will be given a hospital gown to wear and will be asked to remove all jewelry.

Infants and children:
The physical and psychological preparation you can provide for this or any test or procedure depends on your child's age, interests, previous experiences, and level of trust. For specific information regarding how you can prepare your child, see the following topics as they correspond to your child's age:

• Infant test or procedure preparation (birth to 1 year)
• Toddler test or procedure preparation (1 to 3 years)
• Preschooler test or procedure preparation (3 to 6 years)
• Schoolage test or procedure preparation (6 to 12 years)
• Adolescent test or procedure preparation (12 to 18 years)

Bile is a by-product of protein metabolism which is created in the liver and excreted into the intestines via the bile ducts. If bile cannot be removed from the body, it collects in the blood and is seen as a yellow discoloration of the skin and eyes (jaundice).

As well, the pancreas creates digestive fluids which drain via a common bile duct into the intestine, and thus obstruction can prevent the drainage of the fluids and may cause pancreatitis (inflammation of the pancreas).

PTCA may distinguish between obstructive and non-obstructive causes of jaundice and pancreatitis. If there is an obstruction, it can then be located and described.

The results may show ducts that are dilated which may indicate there is an obstruction. The obstruction may be caused by infection, scarring, stones, or cancer in the bile ducts, liver, pancreas, or region of the gallbladder.

Additional conditions under which the test may be performed include the following:

• Biliary obstruction
• Cholangitis

ERCP (endoscopic retrograde cholangiopancreatography) is an invasive procedure performed by gastroenterologists to visualize the bile ducts and to remove obstructing stones. If a diagnostic ERCP cannot be performed, or has failed in the past, PTCA may be performed. MRCP (magnetic resonance cholangiopancreatography) is a newer, noninvasive imaging method, based on MRI, which provides similar views of the biliary ducts in multiple planes.