Presentation
Patient in the late postoperative period for bariatric surgery with complaints of recurrent abdominal pain.
Patient Data
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Radiography of the abdomen shows abnormal distribution of intestinal gas; It seems that the middle-distal ileum courses downwards in the left hypochondrium.
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It is possible to identify CT signs compatible with internal abdominal herniation suggesting Petersen hernia:
- herniated intestinal loop segment above the gastric level
- rotation of mesenteric vessels (whirl sign)
- soft mesenteric fat haziness
- ligament of Treitz displaced anteriorly and to the right and middle-distal ileum coursing downwards in the left hypochondrium
Case Discussion
Petersen hernia is a type of internal hernia which occurs in the potential space posterior to a gastrojejunostomy. In this specific type, the intestine moves into the potential space between the caudal surface of the transverse mesocolon and the edge of the Roux limb. It is usually found in patients with a Roux-en-Y gastric bypass.