Duodenal Diverticula

Congenital diverticula are commonly found on the medial wall of the duodenum adjacent to or involving the papilla of Vater, and as a result are of particular relevance to ERCP. As the neck of the diverticulum is often narrow, the opening is usually small. Diverticula of the duodenum are incidental findings in 1%-5% of barium examinations of the upper gastrointestinal tract. They are acquired lesions consisting of a sac of mucosal and submucosal layers herniated through a muscular defect in the bowel wall. They are found most commonly along the medial border of the descending duodenum where penetrating vessels cause potential weak spots in the bowel wall. Thirty to forty percent of diverticula arise in the third and fourth portions of the duodenum.