Gallstone Ileus

Classical findings: small bowel obstruction; gas in biliary tree; large ectopic gallstone (Rigler triad).
Other findings: collapsed gallbladder; gas in gallbladder.
Terminology: mechanical intestinal obstuction caused by impaction of one or more gallstones.
Pathology: occurs in setting of chronic cholecystitis or following multiple ERCPs. Risk increases with age.
Reference: Federle M. Jeffrey R. Desser T. Diagnostic Imaging: Abdomen 2004. Amirsys. Canada.
Credit: Dr Marina-Portia Anthony
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