NCT07516535

DISS vs FANS in Suction-Assisted RIRS for Medium-Sized Renal Stones

The Impact of Suction-Assisted RIRS (DISS Versus FANS) on Postoperative Infection Rate and Stone-Free Rate After Treatment of Medium Sized Renal Stones

• Status: Not Yet Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 126 (estimated)
• Sponsor: Ain Shams University · Academic / Other
• Sex: All
• Age: 18 Years – 60 Years
• Healthy volunteers: Not accepted

Summary

Kidney stones are a common health problem and may recur frequently, which can affect quality of life and kidney function. Retrograde intrarenal surgery (RIRS) is a minimally invasive treatment used for renal stones, but treatment of medium-sized stones may be associated with longer operative time, impaired visibility during surgery, residual stone fragments, and postoperative infectious complications caused by increased intrarenal pressure. Suction-assisted retrograde intrarenal surgery (RIRS) techniques have been developed to improve surgical efficiency and safety by facilitating continuous removal of stone fragments and helping control intrarenal pressure. Two commonly used suction-assisted approaches are direct in-scope suction (DISS) and flexible and navigable suction ureteric access sheath (FANS). However, there is limited prospective randomized evidence directly comparing these two techniques. This randomized prospective clinical study aims to compare direct in-scope suction (DISS) versus flexible and navigable suction ureteric access sheath (FANS) in adult patients with medium-sized renal stones measuring 2 to 3 cm who are undergoing retrograde intrarenal surgery (RIRS). Participants will be randomly assigned to one of the two suction-assisted techniques. The study will evaluate whether flexible and navigable suction ureteric access sheath (FANS) provides better outcomes than direct in-scope suction (DISS) in terms of stone-free rate and postoperative infection rate. The primary outcome is stone-free status assessed by postoperative imaging. Secondary outcomes include operative time, intraoperative visibility, and postoperative complications, particularly infection and urosepsis. The study hypothesis is that suction-assisted retrograde intrarenal surgery (RIRS) using the flexible and navigable suction ureteric access sheath (FANS) technique will result in a higher stone-free rate and a lower postoperative infection rate compared with direct in-scope suction (DISS) in the management of medium-sized renal stones.

Conditions

• Kidney Stones
• Nephrolithiasis
• Renal Calculi

Interventions

Type	Name	Description
PROCEDURE	Direct In-Scope Suction	Direct suction is applied through the working channel of the flexible ureteroscope during retrograde intrarenal surgery to facilitate evacuation of stone fragments and improve intraoperative visibility during laser lithotripsy.
PROCEDURE	Flexible and Navigable Suction Ureteric Access Sheath	A flexible and navigable suction ureteric access sheath is used during retrograde intrarenal surgery to provide suction-assisted evacuation of stone fragments, improve visibility, and support intrarenal pressure control during laser lithotripsy.

Timeline

• Start date: 2026-04-30
• Primary completion: 2027-04-30
• Completion: 2027-04-30
• First posted: 2026-04-08
• Last updated: 2026-04-08

Locations

1 site across 1 country: Egypt