Covered Metal Ureteral Stents in the Treatment of Benign Short Ureteral Stricture

Study Overview
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Brief Summary
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BSUS patients were prospectively enrolled in this study, and non-randomly treated with balloon dilation +CMUS and balloon dilation + tandem DJ stent. Perioperative data of the patients were recorded to compare their efficacy and complications, and the ureteral stent symptom questionnaire was used to compare their impact on patients' quality of life. CMUS and tandem DJ stents were removed after ≥3 months of indwelling. After the removal of stents, the patients' serum creatinine and renal pelvis width were followed up to compare their curative effect on BSUS.

Detailed Description
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The ureteral stricture is caused by various benign and malignant reasons, and then appears hydronephrosis and progressive decline of renal function. Benign short ureteral stenosis (BSUS) especially refers to ureteral stenosis of no more than 2cm in length caused by benign causes such as impacted ureteral stone or endoscopic lithotomy. Currently, BSUS can be treated with laparoscopic or open ureteroplasty, endoscopic balloon dilation or ureterotomy, ureteral stents insertion, or nephrostomy. Since its introduction, covered metal ureteral stent (CMUS) can be used to treat various types of ureteral stricture, achieving a long-term patency rate of more than 80% for BSUS and even curing some patients. It also has fewer complications than a double-J stent (DJ stent). However, there is still a lack of comparative studies on the therapeutic effect and complications of the two treatment methods, namely CMUS after balloon dilation and tandem DJ stent, for BSUS, especially the evaluation of the curative effect of BSUS. Therefore, BSUS patients were prospectively enrolled in this study, and non-randomly treated with balloon dilation +CMUS and balloon dilation + tandem DJ stent. Perioperative data of the patients were recorded to compare their efficacy and complications, and the ureteral stent symptom questionnaire was used to compare their impact on patients' quality of life. CMUS and tandem DJ stents were removed after ≥3 months of indwelling. After the removal of stents, the patients' serum creatinine and renal pelvis width were followed up to compare their curative effect on BSUS.

Official Title
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Evaluation of Curative Effect of Covered Metal Ureteral Stents in the Endoscopic Treatment of Benign Short Ureteral Stricture: a Prospective Controlled Study

Conditions
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Ureteral Stenosis

Intervention / Treatment
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* Device: Covered metal ureteral stents
* Device: Tandem DJ stents


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: BSUS patients from January 2023 to January 2024 in Peking University People's Hospital, no gender limitation, aged from 18 to 80, Benign ureteral stricture with definite reason (ureteropelvic junction obstruction, ischemic ureter stenosis caused by surgical separation, ureter partial excision anastomosis stricture after operation, ureteral stricture caused by ureteral endoscope surgery, ureteral stenosis caused by impacted ureteral calculi, ureteral anastomotic stricture after urinary flow diversion, ureteral anastomotic stricture after kidney transplantation, retroperitoneal fibrosis, ureteral stricture caused by trauma, idiopathic ureteral stricture), patients can tolerate anesthesia and surgery and obtain informed consent. Exclusion Criteria: Patients with hypertonic neurogenic bladder, severe bladder outlet obstruction or bladder capacity less than 50ml, combined with sepsis, incomplete clinical data, failed stent implantation, insufficient indwelling time (< 3 months), postoperative loss of follow-up.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: CMUS group<br>Balloon dilatation and CMUS insertion were performed in this group. | Device: Covered metal ureteral stents<br>* The CMUS is a fully covered, self-expanding, large caliber metal stent. The stent is made of super-elastic nickel-titanium alloy, which maintain lumen patency via providing long-term direct wall support.<br>|
| Active Comparator: Tandem DJ stent group<br>Balloon dilatation and Tandem DJ stent insertion were performed in this group. | Device: Tandem DJ stents<br>* Tandem DJ stents represents for two stents side-by-side, which improves the urine flow by better withstanding the compressive tumoral forces and allowing urine to flow between the stents.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative Serum Creatinine (SCr) | It represents for the renal function change after ureteral stent insertion. | Postoperative 3-month | 
| Serum Creatinine (SCr) after stent removal | It represents for the curative effect of balloon dilatation and ureteral stent. | Three-month after stent removal | 
| Postoperative Renal pelvic width (RPW) | It represents for the change of hydronephrosis after ureteral stent insertion. | Postoperative 3-month | 
| Renal pelvic width (RPW) after stent removal | It represents for the curative effect of balloon dilatation and ureteral stent. | Three-month after stent removal | 
| Ureteral stent symptom questionnaire (USSQ) | USSQ represents for the quality of life of patients with ureteral stents. | Postoperative 3-month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Complications | Ureteral stent related complications | Postoperative 3-month | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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ureteral stricture, ureteral stent, curative effect