Ileal Atresia

Etiology: In utero vascular accident so it has no other associated congenital abnormalities
Imaging AXR: Distal small bowel obstruction with distended air-filled loops of distal ileum
Imaging Enema:
— Microcolon without any meconium filling defects
— Cannot reflux into the terminal ileum and the upstream dilated ileal loops
DDX:
Complications:
— Intestinal perforation
— Multiple gastrointestinal atresias can exist in the same patient so it is important for surgeon to run the entire bowel during repair
Treatment: Surgical
Clinical:
— Most common intestinal atresia
— 10% have cystic fibrosis

Radiology Cases of Ileal Atresia

Enema of ileal atresia — Enema shows a microcolon with an inability to reflux contrast into the dilated loops of distal small bowel.

Enema of ileal atresia — AXR supine (above left) and AXR left lateral decubitus (above right) show multiple dilated loops of bowel with no gas in the rectum. AP (below left) and lateral (below right) views of an enema show the colon to be small in diameter throughout its length (microcolon) and to contain filling defects representing pellets of meconium. The terminal ileum could not be refluxed despite multiple attempts to do so.

Enema of ileal atresia — AXR (left) shows multiple loops of dilated bowel suggesting a distal bowel obstruction. AP image from an enema (right) shows the colon to be small in caliber (a microcolon). Despite multiple attempts, the terminal ileum could not be refluxed with contrast.

Upper GI of ileal atresia — AP image from an upper GI exam (above) shows the duodenal jejunal junction to be over the left pedicle of the T12 vertebral body in a normal position. AP image obtained 30 minutes later (below) shows progressive passage of contrast into several extremely dilated loops of proximal jejunum.

Radiology Cases of Ileal Atresia Causing Bowel Perforation

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.

Surgery Cases of Ileal Atresia

Surgical image of ileal atresia — Surgical image shows a massively dilated distal ileum (to the left of the image) than then dramatically narrows in the center of the image.

Surgical image of ileal atresia — Surgical image shows an extremely dilated C-shaped loop of distal ileum with a normal caliber terminal ileum being held between the fingers at the top of the image.