Pediatric Small Bowel Perforation

Etiology:
— Placement of a gastrojejunostomy tube
— Use of indomethacin to close a patent ductus arteriosus
— Bowel atresia
— Ischemic necrosis
— Blunt trauma
Imaging CXR upright: Air beneath the diaphragm
Imaging AXR upright: Air beneath the diaphragm
Imaging AXR left lateral decubitus: Air above the liver (air between abdominal wall and liver)
Imaging AXR cross-table lateral:
— For small amounts of free air see tell-tale triangle sign of air between bowel loops
— For large amounts of free air see air superiorly between abdominal wall and viscera
Imaging AXR supine:
— Overall increased lucency of abdomen
— American football sign of falciform ligament
— Inverted Y of umbilical artery ligaments
— Rigler’s sign (see air outlining both sides of bowel wall)
Note:
— Neonates with bowel perforation have an inflamed abdomen and pneumoperitoneum may be loculated and not be classically seen on upright or decubitus or cross-table lateral views and pneumoperitoneum may appear as fixed air collection that does not appear to conform to bowel
— In such cases US showing complex free fluid may assist in making the diagnosis of bowel perforation keeping in mind the differential diagnosis of complex free fluid is bowel perforation or infection or hemorrhage
DDX:
Complications:
Treatment: Surgical
Clinical:

Radiology Cases of Small Bowel Perforation

Radiology Cases of Small Bowel Perforation Due to Jejunal Atresia

AXR of pneumoperitoneum — Supine (left) and upright (right) AXR show a central fixed air collection that does not appear to conform to bowel and does not demonstrate any of the classic signs of free air.

Radiology Cases of Small Bowel Perforation Due to Ileal Atresia

AXR of pneumoperitoneum — Supine AXR shows increased lucency in the upper abdomen without clear demonstration of the American football sign of the falciform ligament being outlined by free air.

Radiology Cases of Small Bowel Perforation Due to Intussusception

AXR of pneumoperitoneum — Supine AXR obtained during an intussusception reduction shows air outlining both the inner and outer walls of the small bowel (Rigler’s sign).

Radiology Cases of Small Bowel Perforation Due to Spontaneous Ileal Perforation

AXR of esophageal perforation from nasogastric tube placement — Supine AXR (above) shows increased lucency in the upper abdomen. The cross-table lateral AXR (below) shows air between the anterior abdominal wall and the bowel. The nasogastric tube follows a very straight course and does not curve towards the stomach. Note on both views that the tip of the nasogastric tube does not project over the stomach. US performed subsequently showed the tip of the nasogastric tube was in the retroperitoneum and not in the stomach.

Radiology Cases of Small Bowel Perforation Due to Spontaneous Intestinal Perforation

CXR and AXR of pneumoperitoneum — CXR AP (above) shows increased lucency in the upper abdomen. Left lateral decubitus AXR (below) shows a large amount of free air between the abdominal wall and the liver.

Radiology Cases of Small Bowel Perforation Due to Bowel Ischemia

AXR of bowel perforation — AXR AP (above) shows a large oval lucency in the midline of the upper abdomen. Cross table lateral AXR (below) shows a large amount of air between the abdominal wall and the liver. There is also air outlining both sides of the bowel wall of a loop of bowel (Rigler’s sign).

Surgery Cases of Small Bowel Perforation

Surgical image of small bowel perforation — Surgical image shows an ileal perforation with the forceps placed through the perforation.

Surgical image of small bowel perforation — Surgical image shows a large hole in the small intestine in the center of the image.