Comprehensive overview of ureteral stents based on clinical aspects, material and design

Abstract

Ureteral stents are useful devices in urological surgery. The main objective of a ureteric stent is to allow passage of urine and reduce early or late complications related to obstruction in the urinary tract. Despite their widespread use, there is a general lack of knowledge and awareness in stent composition and indication of application. We represented a synthesis of our extensive research over materials, coatings and shapes available on the market and then analyzed the main characteristics and peculiarities of ureteral stents. We have also focused our attention over the side effects and complication that must be considered when placing a ureteral stent. Encrustation, microbial colonization, stent-related symptoms and patient's history must always be evaluated when there is the need for a ureteral stent. The perfect stent should have many characteristics including easy insertion and removal, easy manipulation, resistance to encrustation and migration, lack of complications, biocompatibility, radio-opacity, biodurability, affordability (cost-effectiveness), tolerability and optimal flow characteristics. Nevertheless, further research and studies need to be done to provide more information about stent composition and efficacy in vivo. In this narrative review, we covered the basic information and main characteristics of ureteral stents, in order to help clinicians choose the appropriate device needed for a given situation.

Keywords: RIRS; kidney calculi; ureteral obstruction; ureteral stent; ureteroscopy; urolithiasis.

Figure 1

Overview of the most common materials for ureteral stents.

Figure 2

Ureteral stent anatomv. Some stents do not have side holes.

Figure 3

Overview of different coatings for ureteral stents. PTFE – TeflonTM; SIPNS – sequential interpenetrating polymer networks; PVP – polyvinylpyrrolidone, PEI – polyethyleneimine

Figure 4

How to choose the right stent. BUO – benign ureteral obstruction; MUO – malignant ureteral obstruction; UPJ – ureteropelvic junction; PU – polyurethane; SJ – single J; DJ – double J; PSS – pigtail suture stent