The Zilver 518 and 635 biliary stents are self-expandable stents made of nitinol. They are flexible, slotted tubes that provide strength and flexibility in biliary duct upon deployment. Post-deployment, the stents impart an outwardly strong radial force upon the inner lumen of the duct, establishing patency in designated stent region. The Zilver 518 biliary stents is preloaded in a 5 Fr delivery catheter and the Zilver 635 biliary stents is preloaded in a 6 Fr delivery catheter. Stent deployment is controlled by retracting the handle while holding the metal cannula stationary.
