Rigler's sign

Rigler’s sign, also known as the double wall sign, is seen on an x-ray of the abdomen when air is present on both sides of the intestine; a Rigler’s sign is present when air is present on the inside (lumenal side) and the outside (peritoneal side). Air in the peritoneum is considered abnormal, unless the patient had a recent abdominal surgery.

A false double wall sign can result from two loops of bowel being in contact with one another.^[1]

The images shown below are courtesy of RadsWiki.

• 
• 
• 
  Confirmed on CT

• Football sign – another sign of pneumoperitoneum.

Template:WH Template:WS