Abstract
Chronic benign ureteral strictures, a condition where narrowing of the ureter leads to impaired urine flow from the kidney to the bladder, can lead to significant patient morbidity. Two types of metal stents, the covered mesh stent (Uventa™) and the thermo-expandable stent (Memokath 051™), have been used to treat this condition when conventional methods fail. This study examines the long-term outcomes of these stent types, providing valuable insights for urologists in selecting the appropriate treatment strategy.
Keywords
1. Benign ureteral stricture
2. Ureteral stents
3. Thermo-expandable stents
4. Chronic ureter obstruction
5. Ureteral stent success rate
Introduction
Benign ureteral strictures represent a significant clinical challenge due to the risk of progressive renal dysfunction they pose. Traditional treatment methods may involve surgery or temporary ureteral stent placement, but persistent or recurrent strictures often necessitate alternative solutions. Recently, attention has turned to the use of permanent metal stents. This study, published in BMC Urology on May 6, 2019, by Joongwon Choi et al., provides comparative data on the long-term outcomes of two different metal stents for treating these challenging cases.
Materials and Methods
The study was conducted at Samsung Medical Center and approved by its Institutional Review Board (IRB No.: 2018–05–106-001). Forty-six ureter units (UUs) from patients with chronic benign ureteral strictures received either a covered mesh stent (Uventa™) or thermo-expandable stent (Memokath 051™) from 2010 to 2017. Primary success was defined as maintaining patency without additional interventions, while overall success also included cases where further procedures maintained patency.
Results
Both stent types demonstrated comparable outcomes in the first year post-insertion, with primary success rates of 54.9% for covered mesh stents and 70.4% for thermo-expandable stents (p = 0.204). Overall success also showed no significant difference, standing at 78.7% and 75.4%, respectively (p = 0.586). Long-term stent placement positively impacted both success rates, while prior radiation therapy and non-pelvic ureteral stricture locations adversely affected overall success rates. Previous percutaneous nephrostomy (PCN) was a negative predictor for both success outcomes.
Discussion
The study illuminates the viability of both the Uventa™ and Memokath 051™ stents as long-term solutions for chronic benign ureteral strictures, indicating that patient selection is crucial for success. The data show that both stent types have similar effectiveness during the first year after insertion with no significant difference in primary or overall success rates.
Conclusion
This extensive retrospective review by Choi et al. underscores the potential of both covered mesh and thermo-expandable metal stents in managing chronic benign ureteral strictures. Despite varied individual outcomes, the results affirm the necessity of individualized patient assessment in determining the optimal stent choice.
References
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DOI: 10.1186/s12894-019-0465-5