[Self-expanding and expandable bile duct prostheses].

The main problem of conventional endoscopic or percutaneous biliary drainage is the clogging of plastic endoprostheses. Therapeutic advances may be achieved by self-expanding or balloon-expandable braided or slit metal stents due to their large lumen and small surface area. Preliminary clinical studies show excellent early results but a divergent long-term clinical outcome depending on the selection of patients, the implantation technique or the type of the stent. If a long-distance overlap of biliary stenoses is achieved the metal stents may be superior to plastic prostheses due to a reduction of the risk of bile encrustation.