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What is Pneumobilia can be seen in and explain in detail?
Gallstone ileus is a type of acute intestinal obstruction,often seen in elderly and is due to blockage by a bolus or mass of gallstones which commonly enter the intestine through cholecystoduodenal fistula(75%) or rarely through cholecystointestinal or gastric fistulas.Plain Xray abdomen in erect posture shows air in the biliary tract(branching gas pattern,pneumobilia) and multiple air fluid levels.Pneumobilia along with an ectopic stone and intestinal obstruction together constitutes the Rigler's triad. Reference:SRB's manual of surgery,5th edition,page no:648.