Partially Covered Nitinol (Nsems) Versus Partially Covered Steel (Ssems) Self-Expandable Metal Stent In The Palliative Treatment Of Malignant Distal Biliary Obstruction - Preliminary Results From A Prospective, Randomized, Multicenter Trial

Metallic stents have been widely used for the palliation of jaundice caused by malignant bile duct obstruction. Most SEMS are now made of a nickel titanium alloy, nitinol, nSEMS. One of the oldest, but still popular stent, the Wallstent® (Boston Scientific) is however made of a steel alloy, sSEMS. The Wallflex® (Boston Scientific) is a recently developed nSEMS, claimed to be advantageous; i.e. more flexible, but with the same radial force as the Wallstent®. Both stents are partially covered with a silastic polymer (Permalume®) to counteract tumour ingrowth. There is no randomized comparison between the two stents.