Introduction: The metal-based Resonance stent (RS) has traditionally been placed in patients with malignant ureteral obstruction; as such, the long-term utility of RS among patients with benign ureteral obstruction (BUO) remains underinvestigated. Methods: We retrospectively reviewed our database for patients with BUO who underwent RS placement between 2010 and 2020. The impact of chronic RS placement on renal function was evaluated by estimated serum creatinine-based glomerular filtration rate (eGFR), furosemide renal scan, and CT-based renal parenchymal volume measurement. The number of and reason for RS stent exchanges during the follow-up period, incidence of encrustation, and the average indwell time were recorded. A cost analysis of placing the RS vs a polymeric stent was performed. Results: Among 43 RS patients with BUO, at a mean follow-up of 26 months, there was no change in eGFR (p = 0.99), parenchymal volume (p = 0.44), or split renal function of the stent-bearing side on renal scan (p = 0.48). The mean RS indwell time was 9.7 months. Eleven patients (26%) underwent premature stent replacement (6 cases) or removal (5 cases). Stents in 9 patients (32%) were encrusted, of which 4 (44%) required laser lithotripsy. Overall, 25 patients (58%) and 12 patients (28%) had a mean stent indwell time of ≥6 months and ≥12 months, respectively. Placing an RS resulted in a 52%, 37%, and 5.6% cost reduction compared with a regular polymeric stent placement, where it was exchanged every 6, 4, or 3 months, respectively. Conclusions: RS deployment in the patient with a BUO results in cost-effective maintenance of renal function and of renal parenchymal volume at a mean follow-up of 2 years; however, only 28% of patients fulfilled the 1-year criterion for RS indwell time.

中文翻译：

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良性疾病共振支架置入后肾功能和支架耐久性的评估。

简介：金属共振支架（RS）传统上被放置在恶性输尿管梗阻患者中；因此，RS 在良性输尿管梗阻 (BUO) 患者中的长期效用仍未得到充分研究。方法：我们回顾性审查了 2010 年至 2020 年间接受 RS 植入的 BUO 患者数据库。通过估计血清肌酐肾小球滤过率 (eGFR)、呋塞米肾扫描和 CT 评估长期 RS 植入对肾功能的影响基于肾实质体积的测量。记录随访期间更换RS支架的次数和原因、结垢发生率以及平均留置时间。对放置 RS 与聚合物支架的成本进行了分析。结果：在 43 名患有 BUO 的 RS 患者中，平均随访 26 个月，支架一侧的 eGFR (p = 0.99)、实质体积 (p = 0.44) 或分裂肾功能没有变化。肾脏扫描（p = 0.48）。平均 RS 留置时间为 9.7 个月。11 名患者（26%）接受了过早支架置换（6 例）或移除（5 例）。9 例患者（32%）的支架结垢，其中 4 例（44%）需要激光碎石术。总体而言，25 名患者 (58%) 和 12 名患者 (28%) 的平均支架留置时间分别≥6 个月和≥12 个月。与每 6、4 或 3 个月更换一次的常规聚合物支架放置相比，放置 RS 的成本分别降低了 52%、37% 和 5.6%。结论：在 BUO 患者中进行 RS 部署，可以在平均随访 2 年时经济有效地维持肾功能和肾实质体积；然而，只有 28% 的患者符合 RS 留置时间 1 年的标准。