Upper intestinal obstruction due to inverted intraduodenal diverticulum.

Inverted intraduodenal diverticulum is a rare congenital abnormality usually arising near the ampulla of Vater. We describe a case of an inverted duodenal diverticulum in a patient that presented with an upper recurrent intestinal obstruction that required surgery. Recognition of the entity and its anatomic relationships to the ampulla of Vater is essential to the prevention of iatrogenic complications. The inverted intraduodenal diverticulum must be considered in the management of upper intestinal obstruction of unclear origin.