Figure 7. Duodenitis after ERCP in a 37-year-old man. Cannulation of the common bile duct was difficult, and sphincterotomy could not be performed. The patient experienced pain and vomiting after the procedure and recovered within 10 days with conservative treatment. CT was performed with oral and intravenous contrast material on the day of ERCP. CT scan shows marked thickening of the wall of the duodenum (arrow) secondary to inflammation from ERCP. There is also fluid in the right perirenal space and thickening of the Gerota fascia.