Infant with crampy abdominal pain and a mass protruding from the rectum

Air enema of intussusception reduction
AXR scout image (above left) shows a non-obstructive bowel gas pattern. AP image from the start of an air enema begun after manual reduction of the mass into the rectum (above right), shows the tip of the rectal catheter in contact with the mass in the rectum. AP image from later in the study (below left) shows the mass now in the transverse colon near the splenic flexure. Despite multiple attempts the intussusception could not be reduced further and the exam was ended when air was seen outlining the liver and both sides of the wall of the small bowel (Rigler’s sign)(below right). In the operating room the intussusception was reduced manually and a site of perforation could not be found.

The diagnosis was ileocolic intussusception extending all the way out of the rectum, that could not be reduced successfully and which resulted in pneumoperitoneum.