Covered or Uncovered Bile Duct Stents

The study is investigator initiated. Tumors that gives the narrowing of the bile ducts prevents bile from flowing from the liver to the intestine resulting in jaundice and the risk of bacterial growth in bile with severe infections as a result. Unresectable bile duct strictures have routinely been treated them with plastic stents. The plastic stents have been replaced by self expandable metallic stents. These stents remain open longer for reasons that they have a larger diameter so that the bile flows through more easily. One problem with these stents, however, is that the tumor growing through the wire mesh which forms the wall of the stent. This has led to the development of so-called covered stents. Whether covered stents have longer patency is unclear as well as whether they are as safe. There is reason to believe that covered stents remain open longer, but there may be an increased risk of migration and other complications. The purpose is to prospectively and randomized compare the two stent types. The study endpoint is the clogging of the stent or the patient's death. We also monitor complications, regress time of the jaundice and success rate of stent placement