How is cholangiography performed?

Cholangiography is a common method for examining bile duct diseases. Some patients cannot be examined with ordinary X-rays. At this time, some medical contrast agents can be used to enter the bile duct, so that the image of the lesion can be clearly displayed on the X-ray. This method is cholangiography. When doing cholangiography, it is important to communicate well with the patient, relieve the patient's concerns, and actively cooperate with the examination.

How is cholangiography performed?

Examination process : (1) Provide good explanations to relieve the patient's concerns and encourage him to cooperate actively. (2) Carefully inquire about the patient's medical history to find out whether the patient has any contraindications to cholangiography. (3) Use medical contrast agents to enter the bile duct through certain methods and channels, so that the outline of the bile duct imaging site and the image of the lesion can be clearly displayed on the X-ray film. Intravenous cholecystography and cholangiography involve intravenous injection of contrast agents, which are not affected by gastrointestinal absorption and can produce results quickly. Intravenous angiography usually shows the common bile duct and common hepatic duct more clearly 30-40 minutes after injection, and then gradually becomes less clear.

There are many methods of clinical significance cholangiography, which are generally divided into two categories: excretory cholangiography and direct cholangiography. Excretory cholangiography: It is a cholangiography that uses oral or intravenous contrast agents (using the principle that the contrast agents are taken up by liver cells and excreted into the bile duct). This imaging method is suitable for patients whose other organs function normally and who have no complications. Commonly used methods include oral cholecystography, transvenous cholangiography (conventional intravenous cholangiography and infusion intravenous cholangiography), and combined oral and intravenous cholangiography. Direct cholangiography: contrast agents are injected directly into the bile duct through various routes for imaging. Commonly used methods in clinical practice include percutaneous transhepatic cholangiography, endoscopic retrograde cholangiography, laparoscopic cholangiography, surgical cholangiography (intraoperative cholangiography, postoperative cholangiography), etc. The advantage of this type of imaging method is that the contrast agent reaches the lesion site directly, and the imaging effect is relatively ideal. The direction of the intrahepatic and extrahepatic bile duct, abnormal or stenotic diameter, occlusion, bile duct tumors, and gallstones can be clearly displayed. The use of an endoscope allows for direct observation and retrograde angiography, which can provide a fairly clear understanding of the lesions near the ampulla of Vater, and also allow for direct biopsy of lesion tissue in the bile or duodenum.

Precautions

(1) Do not take medicines containing iron, iodine, sodium, bismuth, silver, etc. 2 days before the examination. (2) Avoid eating too much fiber or indigestible foods one day before the angiography. (3) The night before the angiography, eat foods low in residue, such as soy milk, noodles, porridge, etc. (4) On the day of the examination, you should avoid wearing clothes with a lot of metal patterns. Before the examination, you should remove jewelry, belts, coins, keys, and other items in your pocket that may cause artifacts. (5) Do not eat or drink anything on the morning of the imaging session, including drinking water and taking any medicine. (6) Patients need to undergo an iodine allergy test before angiography. Requirements during the examination: Patients only need to follow the doctor's instructions and cooperate. Unsuitable groups: (1) People with esophageal varicose veins or stenosis. (2) Allergy to contrast agent (iodized oil). (3) Acute pancreatitis or acute exacerbation of chronic pancreatitis. (4) Patients with severe cardiovascular disease accompanied by heart failure or frequent angina pectoris. (5) Viral hepatitis, hepatitis B surface antigen positive (Australia antigen positive). (6) Those who are mentally ill and unable to cooperate. (7) Acute biliary tract infection.