DISS vs FANS in Suction-Assisted RIRS for Medium-Sized Renal Stones
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Direct In-Scope Suction, Flexible and Navigable Suction Ureteric Access Sheath.
- Who it may be relevant to
- Registry conditions: Kidney Stones, Nephrolithiasis, Renal Calculi. Basic parameters: 18 years — 60 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Egypt
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
The Impact of Suction-Assisted RIRS (DISS Versus FANS) on Postoperative Infection Rate and Stone-Free Rate After Treatment of Medium Sized Renal Stones
Overview
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.
Interventions
- 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.
Primary outcome measures
- Stone-Free Rate [Time frame: At 1 month after surgery]
Secondary outcome measures (4)
- Postoperative Infection Rate [Time frame: Within 1 month after surgery]
- Operative Time [Time frame: During surgery (Intraoperatively)]
- Intraoperative Visibility Score [Time frame: During surgery (Intraoperatively)]
- Postoperative Complication Rate [Time frame: Within 1 month after surgery]
Eligibility criteria
Inclusion criteria
- Adults aged 18 to 60 years
- Radiologically confirmed renal stones measuring 2 to 3 centimeters
- Eligible for retrograde intrarenal surgery
- Normal renal function as evidenced by normal serum creatinine
- Able and willing to provide written informed consent
Exclusion criteria
- Pregnancy or lactation
- Active urinary tract infection at the time of enrollment
- Bleeding disorders or coagulopathies that contraindicate surgical intervention
- Anatomical malformations affecting the urinary tract
- Solitary kidney
- Inability or unwillingness to provide informed consent
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Allocation
- Randomized
- Model
- Parallel assignment
- Masking
- Open label
- Primary purpose
- Treatment
Study locations
Egypt · 1 center
- Ain Shams University Hospitals — Cairo
Identifiers
NCT: NCT07516535 · FMASU MS 142/2026