Duodenal diverticula Duodenal diverticula can be Extraluminal (which protrude outside the duodenal wall) Intraluminal (which protrude into the duodenal lumen) Extraluminal diverticula of the duodenum are common and are seen in about 25% of patients > 50 years of age who are undergoing endoscopic retrograde cholangiopancreatography; they are periampullary in 75% of these patients.