Figure 3a.  Metallic biliary stent in a 69-year-old woman with pancreatic carcinoma. (a) Endoscopic retrograde cholangiopancreatogram obtained prior to injection of contrast material into the bile duct reveals a metallic biliary stent (arrows). (b) MR cholangiogram demonstrates the fluid-filled bile duct (arrows) despite the presence of the stent. The filling defects within the stent represent adherent debris and may be distinguished from stones by their indistinct margins and their peripheral location within the duct on axial images.