Intramesosigmoid hernia: preoperative diagnostic MDCT findings

Abstract

Internal hernias, protrusion of abdominal viscera into an intraperitoneal fossa, are uncommon causes of bowel obstruction, and preoperative diagnoses are difficult. We report a rare case of a 47-year-old female with strangulated small bowel obstruction secondary to an intramesosigmoid hernia preoperative diagnosis by multi-detector row computed tomography. We highlight the preoperatively diagnosed value and findings of MDCT in intramesosigmoid hernia.

Intramesosigmoid hernia complicated by strangulated small-bowel obstruction

“…There are atypical appearances as reported previously for an intramesosigmoid hernia, where the herniated bowel loops displaced the sigmoid colon posteriorly and superiorly instead 6. In this case, the CT angiogram showed supporting findings of redirection of the vessels that accompany the herniated small bowel with splaying of the sigmoid arteries.…”

“…It is the commonest type of sigmoid-related hernia in the West and is reportedly found in 65% of autopsies 1. It is often easily reducible;6 (2) transmesosigmoid hernia has the bowel herniating through both layers of the mesocolon to lie posterolateral to the sigmoid and the orifice is bound by branches of the inferior mesenteric artery 1. Hence, no hernial sac is formed; and (3) intramesosigmoid hernia is the rarest type in the Western literature but the commonest type in the Japanese literature 5.…”

“…Regardless of whether a more traditional laparotomy6 10 11 or increasingly popular laparoscopic approach is performed, the herniated bowel is reduced or resected if non-viable and the mesocolon is usually closed.…”

Unique case of a laparoscopic hand‐assisted repair of an intramesosigmoid hernia causing bowel obstruction in a virgin abdomen

“…In 1964, Benson and Killen were the first to report this variety with barely more than 50 cases since described . They carry an associated bowel resection of 80% due to rapid progression of necrosis . This is the first report which details a laparoscopic hand‐assisted repair of an IMSH.…”

“…The intersigmoidal types are the most common and involve herniation through the lateral aspect or to the left of the sigmoid mesentery into the intersigmoidal fossa. This occurs in the retroperitoneum where herniated bowel loops protrude into the congenital fossa (formed during fusion of lateral surface of the sigmoid mesocolon with the parental peritoneum of the abdominal wall) …”