Comparison of axial force and cell width of self-expandable metallic stents: Which type of stent is better suited for hilar biliary strictures?

Background Various types of self-expandable metallic stents (SEMSs) are commercially available. However, few reports have compared the performance of the various SEMSs. In addition to long-term patency, maneuverability during initial placement and feasibility of re-intervention for the stent occlusion are also very important. Methods In this retrospective analysis, we compared the duration of stent patency and frequency of re-interventions in 96 patients diagnosed with unresectable hilar biliary strictures in whom initial 10-mm SEMSs were inserted between June 1999 and November 2008. Results Based on Kaplan-Meier curves, significantly shorter patency duration was noted for SEMSs with moderate axial force (AF) than for other groups of SEMSs with low AF. Endoscopic re-interventions for SEMS occlusion were easier in a group of SEMSs with low AF and large cell width than in other groups of SEMSs. Conclusions With respect to patency duration and the frequency of re-intervention required, we consider that SEMSs with low AF and large cell width are favorable for hilar biliary strictures.