Metal stents in gastroenterology

Self-expanding metal stents have, when introduced in their constrained form through gastrointestinal and biliary strictures, a relatively small diamet er. Once placed through the stricture and released, however, they expand to a much larger internal diameter, thus giving rise to sufficient palliative reopening of these strictures. Since metal stents are usually not removabl e, their primary use has been in malignant stenoses. Benign strictures shou ld be treated with metal stents only in exceptional situations. For palliat ion of dysphagia in esophagocardial malignancies, metal stents have been sh own to be associated with significantly fewer initial complications on plac ement than plastic tubes. The long-term fate of both stent types seems to b e similar. In the palliation of malignant jaundice, metal stents were demon strated to have a significantly longer patency rate, resulting in a favoura ble cost-benefit ratio despite the high price of metal stents. Continued de velopments are necessary to further reduce long-term complications and effe ctiveness.