A New Self-Expanding Nitinol Stent (JoStent SelfX) for Palliation of Malignant Biliary Obstruction: a Pilot Study

Background and Study Aims: The JoStent SelfX is a new biliary uncovered self-expanding nitinol stent. The main advantage of this stent in comparison with the ”gold standard” Wallstent is the minimal shortening (< 10 %) that occurs during stent deployment. A prospective feasibility study was conducted to evaluate the method of stent implantation and the stent’s short-term efficacy.
Patients and Methods: Between April 2001 and December 2002, the JoStent SelfX was implanted in 20 patients with inoperable malignant biliary obstructions, mainly caused by pancreatic cancer (12 of 20). All patients underwent sphincterotomy prior to stent insertion. After implantation, laboratory parameters for cholestasis and expansion of the stent were checked over a period of several days. All patients were followed for 8 weeks after implantation to document early stent dysfunction.

Results: Stent implantation was easily managed and successful in all patients, with no technical problems. Prior bougienage was required in only one patient, who had a filiform stenosis. No stent retraction was observed during stent release. All stents showed full expansion within 5 days. No acute complications occurred. Adequate reduction in the elevated laboratory parameters for cholestasis was observed. Two patients had recurrent cholestasis and fever due to cholangitis, or stent occlusion caused by biliary sludge within 4 weeks.
Conclusions: This new biliary metal stent is easily inserted and does not shorten during stent release, allowing precise positioning. No acute complications occurred, but there were two cases of early stent dysfunction. The role of the JoStent SelfX in comparison with other biliary stents will need to be evaluated in a multicenter trial with a larger number of patients, to investigate the long-term results.

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