PMC3014833_01
Abdominal ultrasound showing a dilated common bile duct (11 mm).
CRIM2010-527141.001.jpg
PMC3014833_01_CRIM2010-527141.001.jpg
fig1
MRCP slice showing an air-fluid filled cyst (arrowed) posterior to the head of the pancreas.
CRIM2010-527141.002.jpg
PMC3014833_01_CRIM2010-527141.002.jpg
fig2
In addition, it revealed a "curious" cystic lesion, with an air-fluid level, lying posterior to the head of the pancreas at the level of the distal common bile and pancreatic duct, which appeared to be causing some extrinsic compression (Figure 2). 
CT scan slice showing the air-fluid filled cyst.
CRIM2010-527141.003.jpg
PMC3014833_01_CRIM2010-527141.003.jpg
fig3
This showed a cystic or necrotic mass behind the head of the pancreas, representing an inflammatory lesion, phlegmon, or duodenal diverticular abscess (Figure 3).
Images from the ERCP showing a duodenal ulcer which was draining pus and bile.
CRIM2010-527141.004.jpg
PMC3014833_01_CRIM2010-527141.004.jpg
fig4
An ERCP on her sixth day postadmission revealed a 10 cm duodenal diverticular abscess draining pus and bile, at the level of the major papilla (Figure 4).