Metallic biliary endoprostheses.

In patients with obstructive jaundice caused by unresectable malignant tumors, biliary endoprostheses inserted percutaneously or endoscopically can provide excellent palliation. Conventional plastic stents are associated with a relatively high rate of occlusion caused by biliary sludge. Migration is another significant problem. Self-expandable, metallic stents can be inserted percutaneously via a small transhepatic track but expand to achieve a relatively large internal diameter. This minimizes the problem of occlusion due to encrusted bile and reduces the rate of reintervention. Migration rarely occurs. Metallic stents have also been employed in the management of recurrent benign biliary strictures unsuitable for surgery. In those patients in whom the frequency of radiological intervention is unacceptably high, such endoprostheses can provide a means of preventing restenosis.