Flexible vs Semi-rigid URS

Assiut University

Status: Enrolling

Conditions: Ureteric Stone; Upper Urinary Tract Stones; Flexible Ureteroscopy

Treatments: Procedure: Flexible URS; Procedure: Semi-Rigid URS

Study type: Interventional

Funder types: Other

Identifiers

NCT07247617

Upper third ureteric stones

Details and patient eligibility

About

To compare the efficacy, safety, success rate, operative time, and cost-effectiveness of flexible ureteroscopy versus semirigid ureteroscopy in the management of upper ureteric stones smaller than 2 cm.

The investigators' main concern in this study is Upper third ureteric stones to determine which cases can be treated with Semi-Rigid Ureteroscopy, and which one needs flexible ureteroscopy. This depends on several factors:

1. Division of the upper third of the ureter
2. Stone size
3. Stone impaction
4. Surgeon experience
5. Anesthesia
6. Ureteric dilatation above the stone
7. Mini endoscopy

Full description

Ureteroscopy (URS) is a widely accepted minimally invasive approach for treating ureteric stones, particularly proximal (upper) ureteral stones. Options include rigid, semirigid (often grouped as one), and flexible ureteroscopes. Flexible ureteroscopy allows deflection and access to the proximal ureter and intrarenal collecting system, facilitating treatment of stones that are difficult to reach with rigid ureteroscopes due to anatomical constraints or stone migration. Semirigid ureteroscopy has shown good efficacy, particularly for stones amenable to direct access without complex deflection, offering shorter operative times and lower costs. Studies report stone-free rates of approximately 90-93% for flexible URS and 81-90% for semirigid URS, with flexible URS having somewhat higher success in accessing stones and managing fragment migration. However, flexible URS typically incurs higher costs and longer operative times. Semirigid ureteroscopy is often the initial approach for upper ureteric stones where anatomy, stone size (<2 cm), and location allow straightforward access.

• Flexible ureteroscopy is preferred when stones are located higher in the ureter, difficult to reach by semirigid scopes, or if stone migration into the kidney occurs. It is also favored when more maneuverability is required to treat complex anatomy or large stones.
• Both modalities use holmium laser lithotripsy for stone fragmentation.
• Treatment choice also depends on surgeon preference, availability of equipment, and cost considerations.

Despite advances, there is ongoing debate about the optimal first-line ureteroscopic approach for upper ureteric stones, balancing efficacy, safety, cost, and procedure time. Comparing flexible and rigid/semirigid ureteroscopy outcomes informs treatment algorithms, improving patient care and resource utilization, especially in differing healthcare settings.

Enrollment: 100 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Patients ≥18 years
• upper ureteric stone
• ≤20 mm

Exclusion criteria

• Associated renal stones
• Any contraindications to Anesthesia

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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100 participants in 2 patient groups

Flexible Ureteroscopy

Active Comparator group

Treatment:

Procedure: Flexible URS

Semi-Rigid Ureteroscopy

Experimental group

Treatment:

Procedure: Semi-Rigid URS