Stent-related Symptoms Comparison: Polaris Loop vs Vortek Double-J Stents

Study Overview
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Brief Summary
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Prospective randomized controlled single-blind parallel-group trial in order to compare symptoms related to loop-tail (Polaris Loop) stents versus conventional double J (Vortek) stents after uncomplicated flexible URS.

Detailed Description
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Patients undergoing RIRS for a single renal stone < 2 cm are asked to participate in a prospective randomized controlled single-blind parallel-group study. Ureteral stent is always placed after flexible URS. Patients are prospectively randomized into two groups with a 1:1 allocation: group LT receive loop-tail stents (Polaris ™ Loop - Boston Scientific, Natick, USA), while group DJ receive conventional double J stents (Vortek ® - Coloplast, Humlebaek, DK). Stent removal is planned 4 weeks after the procedure. Participants are asked to fill in the Italian validated version of the Ureteral Stent Symptoms Questionnaire (USSQ) 2 days and 4 weeks after surgery. The USSQ is further submitted 4 weeks after stent removal (8 weeks after surgery) and these results are used as baseline evaluation, on the assumption that SRS persist for a few days after removal.

Official Title
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Comparison Between Symptoms Related to Polaris Loop Stent Versus Vortek Double J Stent After Uncomplicated Flexible Ureterorenoscopy for Renal Stones

Conditions
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Symptoms and Signs, Pain, Renal Calculi

Intervention / Treatment
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* Other: USSQ questionnaire administration after RIRS.


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients undergoing flexible ureteroscopy and laser lithotripsy for kidney stones < 2 cm given informed consent WHO PS 0-2 Exclusion Criteria: significant residual fragments at the end of the procedure intraoperative complications (i.e. ureteral damage or ureteral stricture) urinary tract infections anatomic abnormalities chronic diseases or medications potentially influencing pain perception and urinary symptoms (i.e. alpha blockers and antimuscarinics) preoperative ureteral stenting.

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: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Vortek double-J stent<br>Vortek double-J stent after RIRS. | Other: USSQ questionnaire administration after RIRS.<br>* USSQ symptoms questionnaire administration after RIRS<br>|
| Active Comparator: Polaris Loop stent<br>Polaris Loop ureteral stent after RIRS. | Other: USSQ questionnaire administration after RIRS.<br>* USSQ symptoms questionnaire administration after RIRS<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| USSQ Urinary symptoms scores | Evaluation of significant differences in Urinary symptoms score between the two groups | 4 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| USSQ domains scores | Evaluation of significant differences in USSQ domains' scores between the two groups | 4 weeks | 
| USSQ domains scores | Evaluation of significant differences in USSQ domains' scores between the two groups | 2 days | 
| USSQ domains' scores adjusted for baseline | Evaluation of significant differences in USSQ domains' scores adjusted for baseline between the two groups | 8 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Symptoms and Signs, Pain, Renal Calculi, Ureteral Stent, Ureteroscopy