Investigations

The main distinguishing features of gallstone ileus are small bowel obstruction with the presence of pneumobilia and a gallstone in the right iliac fossa on X-ray/CT (referred to as Rigler's triad): (1)

• gas in the biliary tree:
  • 40% of cases
    
    
• a gallstone in the intestine:
  • often at the ileo-caecal junction
    
    
• small bowel obstruction

In practice, plain abdominal films demonstrate small bowel obstruction, ultrasound scanning shows biliary tract pathology and CT scanning then makes the final diagnosis.

Reference

1. Shekhda KM, Abro AH, Gupta A, et al; Gallstone Ileus. Chonnam Med J. 2021 Jan;57(1):91-92.