Percutaneous transhepatic cholangiography
Encyclopedia
Percutaneous transhepatic cholangiography (PTHC or PTC) or percutaneous hepatic cholangiogram is a radiologic technique used to visualize the anatomy
of the biliary tract. A contrast medium
is injected into a bile duct in the liver
, after which X-ray
s are taken. It allows access to the biliary tree in cases where endoscopic retrograde cholangiopancreatography
(ERCP) has been unsuccessful. Initially reported in 1937, the procedure became popular in 1952.
It is predominantly now performed as a therapeutic technique. There are less invasive means of imaging the biliary tree including transabdominal ultrasound, magnetic resonance cholangiopancreatography
, computed tomography
and endoscopic ultrasound
. If the biliary system is obstructed, PTC may be used to perform biliary drainage until a more permanent solution for the obstruction is performed (e.g. surgery). Additionally, self expanding metal stents can be placed across malignant biliary strictures to allow palliative drainage. Percutaneous placement of metal stents can be utilised when therapeutic ERCP has been unsuccessful, anatomy is altered precluding endoscopic access to the duodenum, or where there has been separation of the segmental biliary drainage of the liver, allowing more selective placement of metal stents. It is generally accepted that percutanous biliary procedures have higher complication rates than therapeutic ERCP. Complications encountered include infection, bleeding and bile leaks.
Anatomy
Anatomy is a branch of biology and medicine that is the consideration of the structure of living things. It is a general term that includes human anatomy, animal anatomy , and plant anatomy...
of the biliary tract. A contrast medium
Contrast medium
A medical contrast medium is a substance used to enhance the contrast of structures or fluids within the body in medical imaging...
is injected into a bile duct in the liver
Liver
The liver is a vital organ present in vertebrates and some other animals. It has a wide range of functions, including detoxification, protein synthesis, and production of biochemicals necessary for digestion...
, after which X-ray
X-ray
X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 120 eV to 120 keV. They are shorter in wavelength than UV rays and longer than gamma...
s are taken. It allows access to the biliary tree in cases where endoscopic retrograde cholangiopancreatography
Endoscopic retrograde cholangiopancreatography
Endoscopic retrograde cholangiopancreatography is a technique that combines the use of endoscopy and fluoroscopy to diagnose and treat certain problems of the biliary or pancreatic ductal systems...
(ERCP) has been unsuccessful. Initially reported in 1937, the procedure became popular in 1952.
It is predominantly now performed as a therapeutic technique. There are less invasive means of imaging the biliary tree including transabdominal ultrasound, magnetic resonance cholangiopancreatography
Magnetic resonance cholangiopancreatography
Magnetic resonance cholangiopancreatography is a medical imaging technique that uses magnetic resonance imaging to visualise the biliary and pancreatic ducts in a non-invasive manner...
, computed tomography
Computed tomography
X-ray computed tomography or Computer tomography , is a medical imaging method employing tomography created by computer processing...
and endoscopic ultrasound
Endoscopic ultrasound
Endoscopic ultrasound or echo-endoscopy is a medical procedure in endoscopy is combined with ultrasound to obtain images of the internal organs in the chest and abdomen. It can be used to visualize the wall of these organs, or to look at adjacent structures...
. If the biliary system is obstructed, PTC may be used to perform biliary drainage until a more permanent solution for the obstruction is performed (e.g. surgery). Additionally, self expanding metal stents can be placed across malignant biliary strictures to allow palliative drainage. Percutaneous placement of metal stents can be utilised when therapeutic ERCP has been unsuccessful, anatomy is altered precluding endoscopic access to the duodenum, or where there has been separation of the segmental biliary drainage of the liver, allowing more selective placement of metal stents. It is generally accepted that percutanous biliary procedures have higher complication rates than therapeutic ERCP. Complications encountered include infection, bleeding and bile leaks.