Brief description of normal duodenojejunal junction location on imaging studies, malrotation hallmarks, and diagnostic imaging findings in midgut volvulus. From Merrow AC Jr. Diagnostic Imaging: Pediatrics. 3rd ed. Elsevier; 2017.

1. Malrotation and volvulus
Imaging findings

2. Normal position of duodenojejunal junction - DJJ
Upper GI
at or left of left vertebral pedicle
almost same level as duodenal bulb on frontal view
US/CT/MRI
D3 crosses to the left of midline
between aorta and SMA

3. Malrotation

4. Best imaging tool
fluoroscopic upper GI through DJJ

5. Most reliable signs
look at D3 and DJJ
• AP: D3 never crosses midline
• LL: D3 has an anterior course
• DJJ to the right of left vertebral pedicle and lower
than duodenal bulb on TRUE frontal views
(symmetric vertebral pedicles)

6. SMA to the right of SMV
not always reliable

7. Small bowel follow through
length of mesentery from DJJ to cecum
determines risk of mesenteric volvulus
 short = high risk

8. Midgut volvulus

9. Infant with bilious vomiting
Classically < 3 months
 emergency upper GI

10. Complete obstruction at D2-D3
with beak sign
 volvulus until proven otherwise
(can be Ladd band too)
 if corkscrew sign at or distal to beak,
then volvulus, not Ladd band
 don’t mistake for duodenal atresia
(double bubble sign and no distal air)

11. Ultrasound
whirlpool sign of SB, mesentery,
and SMV rotated around SMA