IS case 457: Chilaiditi's sign
Imaging Sciences URMC 2010
Publication Date: 2010-08-30
A 90-year-old male presented to the emergency room with frequent falls. A chest x-ray was performed to evaluate for fractures and signs of infection.
PA and lateral views of the chest demonstrated a loop of large bowel seen anteriorly, and superiorly to the liver. Otherwise, no focal areas of consolidation to suggest pneumonia and no fractures.
Chilaiditi's sign refers to the presence of a gas filled loop of large bowel in the right upper quadrant, between the liver and the right hemidiaphragm. Like this patient, it is usually an incidental finding. If the patient has abdominal pain, volvulus, or shortness of breath, along with imaging findings of transposition of the colon, then it is referred to as Chilaiditi's syndrome.
The importance of Chilaiditi's sign is recognizing that it is a normal variant, and should not be mistaken as pneumoperitoneum, which may lead to unnecessary surgery. Differentiating between free air and air within a loop of bowel can be difficult, however, close evaluation for haustra or plicae circulares can be used to confirm the presence of bowel. Another factor to consider is that changing the position of the patient will tend to move free air, but no change in position of the radiolucency will be seen with hepatodiaphragmatic interposition of the colon.
Several causes of hepatodiaphragmatic interposition have been proposed, some of which include: increased colonic mobility, laxity of suspensory ligaments, reduced liver volume, and phrenic nerve palsy.
- Saber A. Boros M. Chilaiditi's syndrome: what should every surgeon know? Am Surg. 2005 Mar;71(3):261-3. PMID: 15869145