Objectives

To describe the important imaging findings on Multidetector Computed Tomography (MDCT) of duodenal diverticulum and its complications, diagnostic tips that can allow a correct differential diagnosis.

Background

Duodenal diverticulum is outpouching from the duodenal wall, usually located along the medial wall of the second and third portions of the duodenum. Duodenal diverticulum sometimes can be easily missed, but often is an incidental finding in asymptomatic individuals.

Imaging findings OR Procedure findings

The CT appearance of a duodenal diverticulum includes a saccular outpouching, that contains air, fluid, an air-fluid level, contrast material, air-contrast level or food debris, usually interposed between the duodenum and the pancreas. Due them intermittently expand and collapse, the duodenal diverticulum has a fluctuating character, so imaging findings can be limited.

Diverticulitis, abscess formation, perforation, bleeding, intestinal obstruction, obstructive pancreatitis or biliary obstruction (Lemmel syndrome) can complicate the duodenum diverticulum.

The differential diagnosis of duodenal diverticulum include an extraluminal periduodenal gas (caused by periduodenal abscess, duodenal ulcer, duodenal injury iatrogenic or trauma, duodenitis) and an extraluminal periduodenal collection of fluid (head of pancreas cystic lesion or pseudocyst).

Conclusion

The radiologist should pay attention to duodenum and adjacent organs in order to recognize and interpretate the CT imaging characteristics of duodenal diverticulum in the scope of reducing the chances of misdiagnosis and inappropriate treatment.