Stents used within the gastrointestinal system, such as biliary stents or pancreatic stents, are generally tubular plastic structures, although metal stents and expandable stents are also sometimes employed. Delivery of these stents is usually accomplished in an endoscopic procedure (e.g. see U.S. Pat. No. 5,876,450). Likewise, retrieval of such stents is accomplished in a separate endoscopic procedure. Retrieval may be accomplished using specialized retrieval devices such as those disclosed in U.S. Pat. Nos. 5,334,208 and 5,643,277, or more conventional devices such as grasping forceps or snares. Some degree of direct visualization of both the stent and device are required in order to retrieve the stents, thus giving rise to the need for the separate endoscopic procedure for removal.
Unfortunately, these stents can sometimes migrate up a patients duct, rendering them difficult to remove. As endoscopic stenting procedures in the biliary and pancreatic ducts become more prevalent, the medical challenge in retrieving these stents will increase. Accordingly, there exists a need to provide devices and methods for retrieval of gastrointestinal stents which improve the ability to remove the stent, including once the stent has migrated up a patient's duct or which otherwise does not require direct visualization of the stent and retrieval device.