Comparison of Flexible & Navigable Suction Ureteral Access Sheath vs. Antegrade Suction in Retrograde Flexible Ureteroscopy for Lower Calyceal Stones

Comparison Study Between Using Retrograde Flexible Ureteroscopy With Flexible & Navigable Suction Ureteral Access Sheath Versus Retrograde Flexible Ureteroscopy With Antegrade Suction in Lower Calyceal Stone: A Randomized Controlled Trial

This randomized controlled trial aims to compare the efficacy and safety of two suction techniques during retrograde flexible ureteroscopy (FURS) for lower calyceal renal stones measuring 1.5-2 cm. The study evaluates Flexible & Navigable Suction Ureteral Access Sheath (FANS) versus Antegrade Suction (via percutaneous access) in improving stone-free rates (SFR), reducing operative time, and minimizing complications such as bleeding, ureteral injury, and infection. A total of 120 adult patients will be randomized into two groups, undergoing either flexible ureteroscopy (FURS) with Flexible & Navigable Suction Ureteral Access Sheath (FANS) or flexible ureteroscopy (FURS) with antegrade suction, at Banha University Faculty of Medicine.

Study Overview

• Status: Not yet recruiting
• Conditions: Nephrolithiasis; Urolithiasis; Endourology
• Intervention / Treatment: Procedure: Flexible & Navigable Suction Ureteral Access Sheath (FANS); Procedure: Antegrade Suction via Percutaneous Nephrostomy

• Study Type: Interventional
• Enrollment (Estimated): 120
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Tamer Diab, MD; Phone Number: +2 01003583264; Email: tamer.diab@fmed.bu.edu.eg

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adult patients (≥18 years old)
• Patients diagnosed with renal stones (1.5-2 cm) confirmed by non-contrast computed tomography (NCCT)
• Patients undergoing flexible ureteroscopy (FURS) as the primary treatment approach
• Patients with no active urinary tract infection (UTI) at baseline
• Patients who provide written informed consent

Exclusion Criteria:

• Patients with anatomical anomalies (e.g., horseshoe kidney, PUJ obstruction)
• Patients with a single functioning kidney
• Pregnant women
• Patients with a history of urological malignancy
• Patients with active bleeding disorders or those on anticoagulant therapy that cannot be safely discontinued
• Patients at high risk for anesthesia

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Flexible & Navigable Suction Ureteral Access Sheath (FANS) Group; Patients in this group will undergo retrograde flexible ureteroscopy (FURS) with the Flexible & Navigable Suction Ureteral Access Sheath (FANS). The FANS facilitates continuous suctioning, improving stone fragment evacuation, reducing intrarenal pressure, and optimizing stone-free rates (SFR).	Procedure: Flexible & Navigable Suction Ureteral Access Sheath (FANS); The Flexible & Navigable Suction Ureteral Access Sheath (FANS) is used during retrograde flexible ureteroscopy (FURS) for renal stones (1.5-2 cm). It allows continuous active suctioning, improving stone fragment evacuation, reducing operative time, lowering intrarenal pressure, and optimizing stone-free rates (SFR). The procedure involves inserting the Navigator 10F, 55 cm YIGAOMED FANS over a guidewire, followed by flexible ureteroscopy with PUSEN® 9.2 Fr ureteroscope and laser lithotripsy using Holmium Laser (JenaSurgical® MultiPulse HoPLUS™ 150W).
Active Comparator: Antegrade Suction with Flexible Ureteroscopy (FURS) Group; Patients in this group will undergo retrograde flexible ureteroscopy (FURS) with antegrade suction, using a percutaneous nephrostomy (PCN) access for suctioning from the kidney during the procedure. This method aims to enhance stone fragment clearance and reduce intrarenal pressure without using a ureteral access sheath.	Procedure: Antegrade Suction via Percutaneous Nephrostomy; This technique involves antegrade suction from the kidney during flexible ureteroscopy (FURS) without the use of a ureteral access sheath. A percutaneous nephrostomy (PCN) tract is created using an 18G needle, and a 6F renal dilator is placed and fixed to the skin, allowing for direct suctioning from the collecting system. Following this, retrograde flexible ureteroscopy (FURS) is performed using the PUSEN® 9.2 Fr ureteroscope and Holmium Laser (JenaSurgical® MultiPulse HoPLUS™ 150W) for stone fragmentation. This technique aims to improve stone clearance while minimizing ureteral trauma associated with access sheaths.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Stone-Free Rate (SFR)	The stone-free rate (SFR) will be assessed one month postoperatively using non-contrast computed tomography (NCCT) to determine the presence or absence of residual stone fragments ≥4 mm. A higher SFR indicates better effectiveness of the intervention.	1 Month Postoperative

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Operative Time	The total operative time will be recorded from the initial endoscopic access to procedure completion. This includes access sheath insertion, ureteroscopy, lithotripsy, and final stone evacuation. A shorter operative time is indicative of a more efficient technique.	During Surgery
Intraoperative Bleeding Requiring Intervention	The incidence of ureteral injuries, including mucosal damage, perforation, or full-thickness injury, will be documented. The severity will be graded based on endoscopic findings and clinical impact.	During Surgery
Ureteral Injury	The incidence of ureteral injuries, including mucosal damage, perforation, or full-thickness injury, will be documented. The severity will be graded based on endoscopic findings and clinical impact.	During Surgery
Postoperative Hematuria	The presence of postoperative hematuria (macroscopic bleeding) will be assessed. It will be classified as mild (self-limited), moderate (requiring irrigation), or severe (requiring intervention such as transfusion or embolization).	Within 7 Days Postoperative
Postoperative Urosepsis	The incidence of postoperative urosepsis, defined as systemic inflammatory response syndrome (SIRS) with a positive urine culture and clinical deterioration requiring IV antibiotics or ICU admission, will be recorded.	Within 7 Days Postoperative

Collaborators and Investigators

• Sponsor: Benha University

Study record dates

Study Major Dates

• Study Start (Estimated): March 30, 2025
• Primary Completion (Estimated): March 30, 2026
• Study Completion (Estimated): March 30, 2026

Study Registration Dates

• First Submitted: March 15, 2025
• First Submitted That Met QC Criteria: March 15, 2025
• First Posted (Actual): March 25, 2025

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: March 15, 2025
• Last Verified: March 1, 2025

More Information

Terms related to this study

• Keywords: Laser Lithotripsy; Flexible Ureteroscopy (FURS); Ureteral Access Sheath (UAS); Suction Ureteral Access Sheath (FANS); Antegrade Suction; Percutaneous Nephrostomy (PCN)
• Additional Relevant MeSH Terms: Urogenital Diseases; Male Urogenital Diseases; Calculi; Pathological Conditions, Anatomical; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Urinary Calculi; Kidney Calculi; Nephrolithiasis; Urolithiasis
• Other Study ID Numbers: MD-290-2025

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: De-identified individual participant data (IPD) will be shared, including baseline characteristics, intraoperative details, postoperative outcomes, and complication data for research purposes. No personally identifiable information will be disclosed.
• IPD Sharing Time Frame: Start Date: Upon publication of primary study results; End Date: Available for 5 years after study completion
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; ANALYTIC_CODE; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No