Tip-flexible Semi-rigid Ureterorenoscope Versus Flexible Ureteroscopy in Renal Calculi

Study Overview
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Brief Summary
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This study evaluates the safety and efficacy of the novel tip-flexible semi-rigid ureterorenoscope for the treatment of renal calculi using a prospective, randomized multicentre trial design. Half of participants will receive retrograde intrarenal surgery using the tip-flexible semi-rigid ureterorenoscope, while the other half participants will receive retrograde intrarenal surgery using the classic flexible ureteroscope.

Detailed Description
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Retrograde intrarenal surgery using flexible ureteroscope has become the first-line treatment for renal calculi < 3.0 cm and is recommended by the European Association of Urology due to its minimally-invasive nature and satisfactory result. However, some limitations still remain. Poor maneuverability, extra costs for the ureteral access sheath, and high device vulnerability still preclude flexible ureteroscopy from wider distribution. Recently, the investigators present a novel ureterorenoscope, which is composed of a retractable rigid sheath and a semi-rigid ureteroscope with a flexible part on the tip. When the flexible tip of the inner shaft maintains within the sheath, working in the rigid mode, the tip-flexible semi-rigid ureterorenoscope is capable of passing either the orifice or the physiological tortuosity of the ureter with ease. When the inner shaft is extended beyond the sheath, the endoscope is switched to the flexible mode, capable of performing an intrarenal approach. This endoscope integrates the classic semi-rigid and flexible ureteroscope both structurally and functionally, and has been approved for clinical application by the China Food and Drug Administration. In this study, transverse comparison is designed to evaluate the safety and efficacy of the tip-flexible semi-rigid ureterorenoscope for the treatment of renal calculi.

Official Title
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Tip-flexible Semi-rigid Ureterorenoscope Versus Flexible Ureteroscopy for the Treatment of Renal Calculi < 3 cm - Efficacity Prospective Randomized Multicentre Trial

Conditions
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Renal Calculi

Intervention / Treatment
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* Device: the tip-flexible ureterorenoscope
* Device: the classic flexible ureteroscope


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subject has provided informed consent and indicated a willingness to comply with study treatments Subject has a diagnosis of renal stones according to computer tomography (CT) and intravenous pyelogram (IVP) results Subject is a surgical candidate for the ureteroscopic approach Subject is 18-80 yrs of age Subject has a single stone < 3 cm in size (IVP), or multiple stones < 3 cm in cumulative size (IVP) Subject has a serum creatinine level within the normal range for the study center Exclusion Criteria: Subject needs bilateral procedures within one-stage ureteroscopy Subject has an active urinary tract infection (e.g., cystitis, prostatitis, urethritis, etc.) Subject has been diagnosed with a urethral stricture or bladder neck contracture Subject has been diagnosed with a urinary tract infection related to stone obstruction within two weeks Subject has severe hematuria that might blur the vision of the endoscopy Subject has a disorder of the coagulation cascade system that would put the subject at risk for intraoperative or postoperative bleeding Subject is unable to discontinue anticoagulant and antiplatelet therapy preoperatively (3-5 d) Subject has other diseases and could not tolerate the endoscopic surgery Subject has any kind of anatomic abnormality of the urinary system that might have an influence on the surgery Subject has ipsilateral pre-stenting or previous ureteroscopy within six months Subject has been diagnosed with hydronephrosis larger than 3 cm according to the B-scan ultrasonography examination

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 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 |
| --- | --- |
| Experimental: tf-URS<br>Participants in tf-URS group undergo ureteroscopy using the tip-flexible ureterorenoscope. | Device: the tip-flexible ureterorenoscope<br>* Ureteroscopy will be conducted using the tip-flexible semi-rigid ureterorenoscope to treat renal calculi. Holmium laser and basket can be used to perform the technique.<br>|
| Active Comparator: f-URS<br>Participants in f-URS group undergo ureteroscopy using the classic flexible ureteroscope. | Device: the classic flexible ureteroscope<br>* Ureteroscopy will be conducted using the classic flexible ureteroscope (Flex x2 STORZ, Germany) to treat renal calculi. Holmium laser and basket can be used to perform the technique.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Stone clearance | Number of participants undergo tf-URS or f-URS surgeries without residual calculus/Total number of participants in each group *100% | 12 weeks post-operatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Stone clearance | Number of participants undergo tf-URS or f-URS surgeries without residual calculus/Total number of participants in each group *100% | One day post-operatively | 
| Complication rates | Number of participants undergo tf-URS or f-URS surgeries suffer complications associated with the surgery (i.e. painess(NRS≥4), hematuria, T≥38℃, serum WBC≥12×〖10〗^9/L ,serum WBC<4×〖10〗^9/L, perforation, etc.)/Total number of participants in each group *100% | Within 12 weeks after surgery | 
| Endoscope deflection loss rates | Number of the broken novel ureterorenoscope or the broken classic flexible ureterosocpe with deflection loss>10%/Total number of ureterorenoscope or ureterosocpe used *100% | intraoperative | 
| Endoscope Leakage rates | Number of the broken novel ureterorenoscope or the broken classic flexible ureterosocpe with leakage of the working channel or the outer shaft/times of the ureterorenoscope or ureterosocpe used *100% | intraoperative | 
| Endoscope black dots rates | Number of the broken novel ureterorenoscope or the broken classic flexible ureterosocpe with black dots on endoscopic images/times of ureterorenoscope or ureterosocpe used *100% | intraoperative | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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retrograde intrarenal surgery, flexible ureteroscopy, renal calculi