Biloma

thumb|261x261px|Duodenobiliary fistula of biliary tree. |alt=Image is an X-ray of Duodenobiliary fistula of biliary tree. It shows pipe like ulcers that result from the fistula.Barium demonstrates contrasts into the bile ducts. A biloma is a circumscribed abdominal collection of bile outside the biliary tree. It occurs when there is excess bile in the abdominal cavity during or after a bile leak. There is an increased chance of a person developing biloma after having a gallbladder removal surgery, known as laparoscopic cholecystectomy. This procedure can be complicated by biloma with incidence of 0.3–2%. Other causes are liver biopsy, abdominal trauma, and, rarely, spontaneous perforation. The formation of biloma does not occur frequently. Biliary fistulas are also caused by injury to the bile duct and can result in the formation of bile leaks. Biliary fistulas are abnormal communications between organs and the biliary tract. Once diagnosed, they usually require drainage.

The term "biloma" was first coined in 1979 by Gould and Patel. They discovered it in a case with extrahepatic bile leakage. The cause of this was trauma to the upper right quadrant of the abdomen. Originally, biloma was described as an "encapsulated collection" of extrahepatic bile. Biloma is now described as extrabiliary collections of bile that can be either intrahepatic or extrahepatic. The most common cause of biloma is trauma to the liver. There are other causes such as abdominal surgery, endoscopic surgery and percutaneous catheter drainage. Injury and abdominal trauma can cause damage to the biliary tree. The biliary tree is a system of vessels that direct secreations from the liver, gallbladder, and pancreas through a series of ducts into the duodenum. This can result in a bile leak which is a common cause of the formation of biloma. It is possible for biloma to be associated with mortality, though it is not common. Bile leaks occur in about one percent of causes.