Location of the fossa: inferior to the third portion of the duodenum; behind the root of the small bowel mesentery; extends rightward and downward into the ascending mesocolon. The superior mesenteric artery and vein run along the anteromedial edge.
Contents: usually small intestine
Risk factor: partial or complete failure of rotation of the midgut
Clinical features:
(1) small bowel obstruction with vomiting
(2) volvulus or intussusception
(3) long-term indigestion or periodic cramps
(4) abdominal distention
(5) postprandial pain that is relieved by a postural change
CT findings:
(1) encapsulated cluster of dilated small bowel loops in the right mid-abdomen or RUQ with a sac-like appearance, lateral and inferior to the descending duodenum
(2) the superior mesenteric vein and superior mesenteric artery are anterior to the defect
(3) jejunal branches of the superior mesenteric vessels may course posteriorly and to the right
(4) variable compression of the right ureter
