Rigler's triad is a combination of findings on an abdominal radiograph of people with

gallstone ileus Gallstone ileus is a rare form of small bowel obstruction caused by an impaction of a gallstone within the lumen of the small intestine. Such a gallstone enters the bowel via a cholecysto-enteric fistula. The presence of large stones, >2.5 ...

, a condition where a large

gallstone A gallstone is a stone formed within the gallbladder from precipitated bile components. The term cholelithiasis may refer to the presence of gallstones or to any disease caused by gallstones, and choledocholithiasis refers to the presence of ...

causes

bowel obstruction Bowel obstruction, also known as intestinal obstruction, is a mechanical or functional obstruction of the intestines which prevents the normal movement of the products of digestion. Either the small bowel or large bowel may be affected. Signs ...

. Rigler's triad consists of: (1) small bowel obstruction, (2) a gallstone outside the

gallbladder In vertebrates, the gallbladder, also known as the cholecyst, is a small hollow organ where bile is stored and concentrated before it is released into the small intestine. In humans, the pear-shaped gallbladder lies beneath the liver, althoug ...

, and (3) air in the bile ducts. It bears the name of

Leo George Rigler Leo George Rigler (16 October 1896, Minneapolis – 25 October 1979) was an American radiologist remembered for describing Rigler's sign. Biography Leo Rigler attended the University of Minnesota, receiving a B.S. in 1917, B.M. in 1919 and M ...

(1896–1979), who described it in 1941. It is not the same as

Rigler's sign Pneumoperitoneum is pneumatosis (abnormal presence of air or other gas) in the peritoneal cavity, a potential space within the abdominal cavity. The most common cause is a perforated abdominal organ, generally from a perforated peptic ulcer, althou ...

. It is most commonly seen in 6th to 7th decade of life and affects females more often. Most patients with gallstone ileus are

asymptomatic In medicine, any disease is classified asymptomatic if a patient tests as carrier for a disease or infection but experiences no symptoms. Whenever a medical condition fails to show noticeable symptoms after a diagnosis it might be considered as ...

. Due to the fistula formation between the

small intestine The small intestine or small bowel is an organ in the gastrointestinal tract where most of the absorption of nutrients from food takes place. It lies between the stomach and large intestine, and receives bile and pancreatic juice through t ...

and gallbladder, large stones can lodge in the small bowel, leading to its obstruction. Pneumobilia means air in the biliary tract. It is due to the transfer of air from bowel through the

fistula A fistula (plural: fistulas or fistulae ; from Latin ''fistula'', "tube, pipe") in anatomy is an abnormal connection between two hollow spaces (technically, two epithelialized surfaces), such as blood vessels, intestines, or other hollow or ...

into the biliary tract.

References

{{Reflist Radiologic signs Medical triads