The abdominal x-ray shows
- Dilated central small bowel loops.
- Branching gas pattern over the liver indicating the presence of pneumobilia.
The above two findings should raise suspicion for a gall stone ileus.
Gall stone ileus is a cause of small bowel obstruction in elderly patients. Rigler’s triad, which consists of three specific radiological signs, provides an indication of gall stone ileus:
- Dilated small bowel loops (80%)
- Pneumobilia (67%)
- Calcified gall stone in an ectopic location, commonly in the distal ileum (50%)
Further reading: https://www.eurorad.org/case/9958