Partial Duodenal Obstruction in Pediatrics

Intrinsic Causes

The American College of Radiology states that partial duodenal obstruction in pediatric patients is most commonly caused by duodenal stenosis, incomplete duodenal webs, annular pancreas, and malrotation with intermittent volvulus, with duodenal stenosis presenting more insidiously than complete atresia 1, 2
Duodenal stenosis results from incomplete failure of recanalization of the primitive gut lumen during embryologic development, creating a narrowed but patent lumen, according to the American College of Radiology 2
Incomplete duodenal web represents type I duodenal atresia with a mucosal web containing a small central perforation allowing partial passage of contents, and can present beyond the immediate newborn period with feeding intolerance and failure to thrive, as recommended by the American College of Radiology 1, 2

Malrotation can present with partial obstruction from Ladd bands compressing the duodenum or from intermittent midgut volvulus, with an associated risk of 28% of duodenal atresia cases, according to the American College of Radiology 1, 3, 4
The American College of Radiology recommends that upper GI series is the reference standard for diagnosing malrotation, showing abnormal position of the duodenojejunal junction (ligament of Treitz), though false-negative rates of 3% and false-positive rates of 10-15% occur 3, 4

The American College of Radiology suggests that plain abdominal radiographs showing dilated stomach and proximal duodenum with variable distal gas suggest partial obstruction, and that upper GI series is essential for diagnosing partial obstruction, showing delayed passage of contrast through a narrowed segment 1, 4, 5
The American College of Radiology states that ultrasound has limited utility for duodenal obstruction diagnosis compared to fluoroscopic studies 5