A 48 year old man came with abdominal pain and vomiting since one month
On contrast enhanced CT scan of abdomen, an air filled outpouching with a thin wall is seen arising from the medial aspect of the second part of the duodenum (D2) adjacent to the papilla. It measures about 11.5 mm. It compresses the distal CBD , There is no wall defect or adjacent fluid or gas collection. There is mild dilatation of the intrahepatic biliary radicles. Distal to this the CBD is normal