A Multicenter Prospective Research on the Treatment of Low Pole Renal Calculus by Flexible Ureteroscope

Study Overview
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Brief Summary
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This study centers on the treatment of low pole renal stones by flexible ureteroscope and intends to find the key anatomical parameters using a prospective, randomized multi-center trial design and to make a more appropriate standard for flexible ureteroscopy of low pole renal stones.

Detailed Description
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With the development of manufacturing technique, new generation of flexible ureteroscopes have great initiative and passive bending capacity and have greatly expanded its application. In our clinical practice, we have found that IPA (Infundibulopelvic angle) is no longer a decisive factor for the success of f-URS（flexible ureteroscope） surgeries. Thus, we think it is necessary to have further study on the effect of anatomy of renal collecting system for f-URS surgeries.

Official Title
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A Multicenter Prospective Research on the Treatment of Low Pole Renal Calculus by Flexible Ureteroscope

Conditions
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Renal Calculus

Intervention / Treatment
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* Procedure: Flexible Ureteroscopy


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 is 18-70 yrs of age Subject can be either male or female Subject has a diagnosis of low pole renal stones according to CT urography(CTU) or intravenous pyelogram (IVP) results Subject has a single stone 1 2cm in size (KUB), or multiple stones 1 2cm in cumulative size (KUB), and is a surgical candidate for the ureteroscopic approach Exclusion Criteria: • 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 is pregnant or in monthly period Subject has coexistent disease like systemic disease, heart disease, lung disfunction or other diseases that could not tolerate the endoscopic surgery or anesthesia. Subject has unadjusted diabetes or high blood pressure 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 (2 weeks) Subject has been diagnosed with hydronephrosis larger than 3cm according to the B-scan ultrasonography examination Subject has any kind of anatomic abnormality of the urinary system that might have an influence on the surgery

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Low Pole Renal Calculus<br>patients with low pole renal calculus who are suitable to treat by flexible ureteroscopy | Procedure: Flexible Ureteroscopy<br>* the Treatment of Low Pole Renal Calculus by Flexible Ureteroscope<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| whether the f-URS could enter the low kidney calyx or not | Following conditions are regarded as failures: 1. the f-URS couldn't enter the low kidney calyx 2. Though the f-URS has entered the low kidney calyx, it cannot crush the stone. | during the operation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| stone clearance | Check NECT（nonenhanced CT）, no residual or residual stones are smaller than 2mm in total refers to clear success.Number of participants undergo f-URS surgeries without residual calculus/Total number of participants in each group *100%=stone clearance | 4 weeks post-operatively | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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anatomical parameters, flexible ureteroscopy, lowl pole renal calculus