Air within the biliary tree is known as which finding?

Air within the biliary tree is known as which finding?

• A. Hemobilia
• B. Pneumobilia
• C. Biloma
• D. Adenomyomatosis

Answer: (B)

Air within the biliary tree is pneumobilia. On ultrasound this shows up as bright echogenic foci inside the bile ducts with reverberation artifacts; the air may move with changes in patient position. Pneumobilia most often occurs after biliary instrumentation or surgery that creates a connection between the gastrointestinal tract and the biliary system (for example, ERCP with sphincterotomy or biliary-enteric anastomosis), or from a fistula with the gut. It’s distinguished from other biliary gas findings by being inside the ducts rather than in a collection outside the biliary system or within the gallbladder wall. Hemobilia would be blood in the ducts; a biloma is a bile collection outside the ducts; adenomyomatosis is gallbladder wall thickening with intramural diverticula.

Air within the biliary tree is pneumobilia. On ultrasound this shows up as bright echogenic foci inside the bile ducts with reverberation artifacts; the air may move with changes in patient position. Pneumobilia most often occurs after biliary instrumentation or surgery that creates a connection between the gastrointestinal tract and the biliary system (for example, ERCP with sphincterotomy or biliary-enteric anastomosis), or from a fistula with the gut. It’s distinguished from other biliary gas findings by being inside the ducts rather than in a collection outside the biliary system or within the gallbladder wall. Hemobilia would be blood in the ducts; a biloma is a bile collection outside the ducts; adenomyomatosis is gallbladder wall thickening with intramural diverticula.