Paraduodenal Hernia

Paraduodenal hernias are a type of internal hernia whereby an abdominal organ passes through a defect into another compartment within the abdominal cavity. These hernias are congenital and arise from anomalous rotation and fusion of mesentery and parietal peritoneum during embryogenesis. There are two types of paraduodenal hernia: the left paraduodenal hernia and the right paraduodenal hernia. Left paraduodenal hernias are three times more common than right paraduodenal hernias. Paraduodenal hernias may not cause symptoms and may be discovered incidentally, though bowel incarceration and strangulation can occur.

Left Paraduodenal Hernias


Left paraduodenal hernias penetrate the fossa of Landzert and enter the descending mesocolon. Small bowel loops pass into the left upper quadrant in a sac separate from other bowel, lateral to the distal duodenum. These hernias are distinguished by the left colic artery and the inferior mesenteric vein in the anteromedial border of the left paraduodenal hernia sac.

Right Paraduodenal Hernias


Right paraduodenal hernias occur through the fossa of Waldeyer into the ascending mesocolon. These hernias are lateral and inferior to the descending duodenum, forming small bowel loops in a sac that are not separable. CT may demonstrate branches of the superior mesenteric or ileocolic arteries in the ventral wall of the hernia sac.

 

2002 by the Rector & Visitors of the University of Virginia