Ureteric stents: The past, present and future

Ureteric stents are fundamental to modern-day urological practice. This article aims to chronicle their development over the last century and the key individuals whose efforts have made their development possible. Early stents were ureteric catheters that were exteriorised outside the body and were associated with complications including migration, infection and encrustation. The use of polyethylene stents in humans was first reported by Tulloch in 1952. Polyethylene was thought to be a promising material due to its durability and water-repellent nature. It would, however, suffer the problems that would become associated with stents over the following decades mentioned above. The first silicone ureteric stents were developed in the 1960s by Zimskind and provided prolonged, efficient drainage but were complicated with stent migration. Collars, wings, flanges and barbs were developed to help prevent migration. Finney developed a double 'pig-tail' stent in the 1970s which helped to prevent both proximal and distal migration and the modern-day ureteric stent was born. Modern polymers have been developed such as polyurethane or styrene ethylene-butylene (C-flex (R)). Metal stents have also been used over the last three decades including the Wallstent, Resonance (R) and Memokath stents. They have shown promising results particularly when long-term relief of ureteric obstruction is needed. Various strategies are available for removal including cystoscopically, stents with a metallic end that can be removed by using a catheter with a magnet at the proximal end, tethered stents that can be removed noninvasively either by the urologist, nurse or even by the patient and dissolvable stents which are in development.