Figure 5. Intramural duodenal air after ERCP in a 55-year-old woman. ERCP was performed for evaluation of an ampullary tumor. Cannulation of the common bile duct was unsuccessful, and extravasation of contrast material from the duodenum was seen during the procedure. CT was performed with oral and intravenous contrast material 3 days after ERCP. CT scan shows air (arrow) in the dependent wall of the duodenum, which represents pneumatosis. The common bile duct is dilated, a finding compatible with the history of ampullary tumor. The patient was treated medically, and repeat CT performed 11 days later showed no evidence of an abscess.