Recanalization of a Petersen Defect After Prophylactic Closure: A Case of Internal Hernia Following Laparoscopic Distal Gastrectomy.

Petersen hernia (PH) is a type of internal hernia in which a portion of the small intestine protrudes through a defect located between the small bowel limbs, transverse mesocolon, and retroperitoneum after any type of gastrojejunostomy. The laparoscopic approach facilitates the occurrence of this type of hernia owing to the lack of postoperative adhesions, which otherwise help prevent bowel motility and herniation. Closure of this anatomical space, formed between the jejunal mesentery, transverse mesocolon, and retroperitoneum, has been shown to significantly lower the incidence of hernia and associated complications such as bowel obstruction and strangulation. We report the case of a 41-year-old woman who underwent laparoscopic distal gastrectomy with a Roux-en-Y reconstruction and prophylactic closure of the Petersen's defect (PD) two years earlier for gastric cancer. She presented with abdominal pain and postprandial vomiting of three days' duration. Her abdomen was slightly distended, and tenderness was noted in the upper abdomen. Laboratory examination results were unremarkable. Contrast-enhanced CT revealed an internal hernia. Exploratory laparoscopy was performed, revealing a reopened Petersen space hernia of the common limb, with obstruction and dilatation of the biliary limb. The incarcerated bowel was repositioned, and there was no evidence of ischemia. The PD was closed using non-absorbable sutures. Awareness of this postoperative anatomical defect, including the possibility of its recurrence even when initially closed, is essential for appropriate management, given the nonspecific nature of its clinical and laboratory findings. Maintaining a low threshold for diagnosis and ensuring early surgical intervention are warranted to prevent serious complications related to bowel necrosis.