Percutaneous transhepatic cholangiogram
A percutaneous transhepatic cholangiogram (PTCA) is an x-ray of the bile ducts inside and outside the liver. The x-ray is taken after contrast medium (dye) is injected directly into the bile ducts.
PTCA; Cholangiogram - PTCA
How the test is performed
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 your abdomen will be cleansed and you will be given a local anesthetic. A long, thin, flexible needle is then inserted through the skin into the liver.
With guidance from an x-ray machine that projects images onto a TV screen (fluoroscope), 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.
How to prepare for the test
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.
How the test will feel
There will be a sting as the anesthetic is given and some discomfort as the needle is advanced into the liver. You may be given medication for sedation and/or pain control. Generally, the x-ray itself causes little or no discomfort.
Why the test is performed
Bile is a by-product of protein metabolism. It is created in the liver and removed from the body through the intestines via the bile ducts. It contains bilirubin, which is a product of normal metabolism. If bile cannot be removed from the body, bilirubin collects in the blood and is seen as a yellow discoloration of the skin and eyes (jaundice). One cause of this is a blockage of the bile ducts.
Also, the pancreas creates digestive fluids, which drain via a common bile duct into the intestine. A blockage can prevent the fluids from draining, and may cause pancreatitis (inflammation of the pancreas).
A PTCA test can help identify whether a blockage is causing the jaundice or pancreatitis.
The bile ducts are normal in size and appearance for the age of the patient.
What abnormal results mean
The results may show that the ducts are enlarged, which may indicate the ducts are blocked. The blockage may be caused by scarring or stones. It may also indicate cancer in the bile ducts, liver, pancreas, or region of the gallbladder.
What the risks are
There is a slight chance of an allergic reaction to the contrast medium (iodine).
There is a slight chance of excessive blood loss, blood poisoning (sepsis), and inflammation of the bile ducts.
This test has been mostly replaced by an endoscopic retrograde cholangiopancreatography (ERCP) test. A PTCA may be done if an ERCP test cannot be performed or has failed.
A magnetic resonance cholangiopancreatography (MRCP) is a newer, noninvasive imaging method, based on MRI. It provides similar views of the bile ducts, but is not always possible to perform.
ReferencesAlfdahl NH. Diseases of the gall bladder and bile ducts. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 159.
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and George F. Longstreth, MD, Department of Gastroenterology, Kaiser Permanente Medical Care Program, San Diego, California. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.