Flexible Ureteroscopy With and Without Ureteral Access Sheath in Treatment of Large Renal Stones

Study Overview
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Brief Summary
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The aim of this study is to evaluate the flexible ureteroscope (FURS) technique with and without ureteral access sheath (UAS).

Detailed Description
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Treating a large renal stone, more than 2 cm, is changing during the last decades. Technological innovations have led to a significant improvement in flexible ureteroscopes over recent years. Many authors have used flexible ureteroscope (FURS) with laser fragmentation as proved treating modality with high efficacy. Although percutaneous extraction of large renal stones is still the first option, it has higher and more severer complications than flexible ureteroscopy. FURS has developed into a standard diagnostic and treatment modality for upper urinary stone disease, transitional cell carcinoma and ureteral strictures. Indeed, more recently FURS is becoming a minimally invasive competitor to percutaneous nephrolithotomy for larger kidney stones as well as an accepted modality for localized treatment of small upper urinary tract transitional cell carcinoma. The use of ureteral access sheath (UAS) is widely recognized as a technique utilized to keep the intrarenal pressure low when performing FURS for larger and more complex stones, although some authors advocate its use for most renal stones. UASs are now produced with varying characteristics including various lengths, diameters, materials, dilator tip designs, radiopaque markers, and stiffness. However, it also rises surgical costs and may injure the ureteral wall. Most common reasons cited by urologists for using a UAS are to facilitate repeated entrance into the ureter and collecting system (as a time-saver), lower intrarenal pressure and protection of ureteroscope and ureter when extracting stone fragments. UAS has encouraged urologists in the fragmentation of large stones; it facilitates multiple entries and stone extraction during FURS.

Official Title
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Flexible Ureteroscopy With and Without Ureteral Access Sheath in Treatment of Large Renal Stones: a Randomized Controlled Trial.

Conditions
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Flexible Ureteroscopy, Ureteral Access Sheath, Large Renal Stones

Intervention / Treatment
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* Procedure: Flexible ureteroscope with ureteral access sheath
* Procedure: Flexible ureteroscope without ureteral access sheath


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age > 18 years old. Both sexes. Patients with upper ureter and renal stones scheduled for flexible ureteroscope. Exclusion Criteria: Patients with associated distal ureteral stone, kidney transplant or any kind of urinary diversion. Larger stones (11 cm) where the routine use of an access sheath will be felt appropriate to aid multiple passes of the scope. Known ureteric strictures. Concomitant ureteric stones. Patients with narrow ureter where ureteral access sheath was anticipated to be difficult.

Ages Eligible for Study
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Minimum Age: 18 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: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Flexible ureteroscope with ureteral access sheath<br>Stones will be treated by flexible ureteroscope with ureteral access sheath | Procedure: Flexible ureteroscope with ureteral access sheath<br>* The flexible ureteroscope either directly or via an access sheath, depending on the size of the ureter, a 9.5/11.5 Fr or a 12 Fr access sheath will be used.<br>|
| Active Comparator: Flexible ureteroscope without ureteral access sheath<br>Stones will be treated by flexible ureteroscope without ureteral access sheath | Procedure: Flexible ureteroscope without ureteral access sheath<br>* Ureteroscopy will be carried out without a ureteral access sheath<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Operative time | Time from sterilization till the end of surgery | Intraperatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Complications | Complications such as mucosal lacerations, bleeding, urosepsis, and stein Strasse. | 28 days after intervention | 
| Duration of stay | Time from admission till hospital discharge | 28 days after intervention | 
| Number of patients who need ancillary procedures | Need for Ancillary Procedures if there was residual. | 28 days after intervention | 
| Stone-free rate | Stone-free status was defined as no residual stones or residual stones with a maximum diameter ≤ 4 mm with no clinical symptoms at 1 month after the procedure | 28 days after intervention |