Supine abdominal plain film
Abdominal imaging
Case TypeClinical Cases
AuthorsR. Jelassi, F. Réty, JC Le Van An, M. Brauner
Patient73 years, female
Because of the diagnosis of gallstone ileus made on the CT scan, an emergency laparotomy was performed. A gallstone was identified within the ileum.
Enterolithotomy alone was performed. The patient had no biliary symptoms on follow-up.
Gallstone ileus results from a bilioenteric fistula with impaction of one or more gallstones anywhere betwen the stomach and rectum. Three quarters of fistulae occur between the gallblader and duodenum. A gallstone must measure at least 2cm in diameter to impact in the bowel. Terminal ileum, which is the narrowest part of the bowel, is the most frequent site of obstruction. Bouveret syndrome is uncommon and is caused by impaction of a gallstone in the duodenal bulb.
Clinical features of gallstone ileus are rarely specific. Intermittent symptoms of incomplete intestinal obstruction are seen but are non-specific. Previous pathology of the biliary tree or of the gallblader is seen in 30-60% of cases. The classic radiographic triad of Rigler, which associates features of pneumobilia, ectopic gallstone and small bowel obstruction, is pathognomonic of gallstone ileus. However, these three radiological features are only present in 30% of cases of gallstone ileus. Each one of these three radiological signs by itself is not specific of gallstone ileus.
Ultrasound may show air in the biliary tree and in the gallblader, a calcified ectopic gallstone and dilated small bowel loops, which are most frequently filled with large quantities of liquid but little gas. However, the usefulness of this imaging modality is highly dependent on the patient's echogenicity and on the skills of the operator.
CT imaging is probably the best imaging modality for the diagnosis of gallstone ileus. It allows good visualisation of pneumobilia, cholecystoduodenal fistulae and moderately or uncalcified ectopic gallstones. Moreover, CT scanning confirms intestinal obstruction, especially when bowel loops are fluid-filled but with little gas, and shows the site of the obstruction.
[1] Coulier B, Coppens JP, Broze B. Computed tomographic diagnosis of biliary ileus. J Belge Radiol 1998;81(2):75-8. (PMID: 9640871)
[2] Delabrousse E, Bartholomot B, Sohm O, Wallerand H, Kastler B. Gallstone ileus: CT findings. Eur Radiol 2000;10(6):938-40. (PMID: 10879707)
[3] Oikarinen H, Paivansalo M, Tikkakoski T, Saarela A. Radiological findings in biliary fistula and gallstone ileus. Acta Radiol 1996;37(6):917-22. (PMID: 8995466)
URL: | https://www.eurorad.org/case/1518 |
DOI: | 10.1594/EURORAD/CASE.1518 |
ISSN: | 1563-4086 |