Ureteral stents: new ideas, new designs

Abstract

Ureteral stents represent a minimally invasive alternative to preserve urinary drainage whenever ureteral patency is deteriorated or is under a significant risk to be occluded due to extrinsic or intrinsic etiologies. The ideal stent that would combine perfect long-term efficacy with no stent-related morbidity is still lacking and stent usage is associated with several adverse effects that limit its value as a tool for long-term urinary drainage. Several new ideas on stent design, composition material and stent coating currently under evaluation, foreseen to eliminate the aforementioned drawbacks of ureteral stent usage. In this article we review the currently applied novel ideas and new designs of ureteral stents. Moreover, we evaluate potential future prospects of ureteral stent development adopted mostly by the pioneering cardiovascular stent industry, focusing, however, on the differences between ureteral and endothelial tissue.

Keywords: double pigtail; drug-eluting stent; metal stents; resonance; stents; ureteral stents.

Figure 1.

Stented ureter with multiple metal mesh stents. The patient was suffering from extensive retroperitoneal metastasis of malignant disease.

Figure 2.

The lower pigtail end of a full metal double-pigtail resonance stent. Note the unique spiral metal structure of the stent which provides adequate resistance to external tension.