Kidney CalculiNCT06684756
Comparison of Vacuum-Assisted and Conventional Ureteral Access Sheath in Retrograde Intrarenal Surgery
A study testing Retrograde intrarenal surgery in people with Kidney Calculi and Kidney Stones, run by Namik Kemal University at 1 site in Turkey (Türkiye).
Trial summary
This study aims to compare the efficacy and safety, the ratio of stone-free rates, and complications of two types of access sheaths used in retrograde intrarenal surgery to treat upper urothelial stones. The access sheath types are those with vacuum aspiration and the conventional ones. Read more about this study
- Who is it for?
- Ages 18 to 85 years
- Conditions the study is for
- Kidney Calculi, Kidney Stones
- What is being tested?
- Retrograde intrarenal surgery
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 150 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 1 Oct 2024to 1 Dec 2026
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 85 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Patients over 18 years of age
- Patients below 85 years of age
- Patients with 11-13 FR conventional/vacuum-assisted ureteral access sheath (UAS) during retrograde intrarenal surgery
Who cannot join
- Patients with non-sterile preoperative urine culture
- Patients with renal anatomic anomalies
- Patients with a solitary (single) kidney
- Patients with insufficient data
- Patients under the age of 18, above the age of 85
- Patients without an UAS during RIRS
- Patients without 11-13Fr UAS during RIRS
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Turkey (Türkiye)1 site, 1 recruiting
- Recruiting
Tekirdag Namık Kemal University
Tekirdağ, Turkey
About this study
Official title: The Comparison of the Efficacy and Safety of Vacuum-Assisted and Conventional Ureteral Access Sheath in Retrograde Intrarenal Surgery: A Randomized Controlled Prospective Multicenter Study
This study aims to compare the efficacy and safety, the ratio of stone-free rates, and complications of two types of access sheaths used in retrograde intrarenal surgery to treat upper urothelial stones. The access sheath types are those with vacuum aspiration and the conventional ones.
Read the detailed description
The use of ureteral access sheath (UAS) during Retrograde Intrarenal Surgery (RIRS) has been proven effective and reliable in recent years, and publications indicate that it reduces stone-free rates (SFR). Their use is also recommended in the European Urology Guidelines because it improves image quality, reduces intrarenal pressure, and shortens the operation time. For this reason, it has been routinely used in many RIRS cases. In cases where non-vacuum-assisted UAS is used, fragments during stone fragmentation remain in the kidney, and since it is not possible to remove the stones simultaneously, the image may be distorted, and the operation duration may be prolonged. All these may pave the way for postoperative infectious complications. In addition to non-vacuum-assisted UAS, new UASs with flexible ends and vacuum-assisted aspiration have been introduced in the last few years (ClearPetra). Thanks to the aspiration connected to the system, stone fragments can be removed from the body with negative pressure during stone fragmentation. Continuous circulation prevents bleeding during fragmentation and blurring of the visual field due to stone fragments. In addition, since the stone fragments pass through the edges of the sheath without breaking and are removed, a perfect field of view can be provided. Unlike the classical UAS, the tip is flexible, allowing for the safe removal of lower pole stones. Many studies in the literature compare the success and complications of RIRS in cases where conventional UAS was used and not used. In addition, there are publications related to using the newly introduced aspiration access sheath in percutaneous nephrolithotomy. In retrospective publications on using this UAS in RIRS, it has been shown that stone-free rates, operation time, hemoglobin loss, and postoperative infective complications are more successful on the 1st and 30th postoperative days compared to cases where non-vacuum-assisted UAS was used. There is no randomized controlled prospective publication on this subject. This study aims to compare the complications and stone-free rates of RIRS cases where non-vacuum-assisted UAS and new vacuum-assisted UAS were used.
- Conditions
- Kidney Calculi, Kidney Stones
- Being tested
- Retrograde intrarenal surgery
- Keywords
- kidney stone, retrograde intrarenal surgery, ureteral access sheath, vacuum assisted
- Medical subject headings
- Kidney Calculi
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Retrograde intrarenal surgeryProcedure or surgery
Flexible optic devices and lasers fragment kidney stones during this operation. In this surgery, an ureteral access sheath is recommended to be used.
| Study group | Role | What they receive |
|---|---|---|
| Patients with conventional UAS being used in their RIRS operations | Active comparator | The patient population will be selected from cases determined by randomization and used with UAS without an aspiration (conventional) during RIRS. Receives: Procedure: Retrograde intrarenal surgery |
| Patients with vacuum assisted UAS being used in their RIRS operations | Experimental | The patient population will be selected from cases determined by randomization and used with UAS with an aspiration and flexible tip, different from the conventional one during RIRS. Receives: Procedure: Retrograde intrarenal surgery |
What is being measured
The primary outcome is the main question the study is designed to answer.
Stone free rates
Presence/absence of residual fragments in postoperative imaging, if any, diameter of longest axis in mm.
Measured: Stone-free status will be checked by performing a non-contrast abdominal CT scan 1 month after the operation.
Secondary outcomes (1)
Complication rates
Peroperative and postoperative complication rates, whether UAS related or not
Measured: Peroperative complication rates will be determined during the operation, and postoperative complications will be re-evaluated during hospitalization before discharge or in the first month after discharge.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted12 Nov 2024
- Study start1 Oct 2024
- Primary completion1 Oct 2025
- Study completion1 Dec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (4)Papers the sponsor has linked to this study.
- Other trials for Kidney CalculiStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 150 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Namik Kemal University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Mehmet Fatih Şahin, Namik Kemal University
- Investigators
- Cenk M. Yazici, Professor, Study director, Namik Kemal University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06684756
- Sponsor's protocol ID
- 2024.288.10.16
- Status last verified
- Jul 2026
- First submitted
- 8 Nov 2024
- Last updated
- 8 Jul 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Wang D, Xu Y, Liu Z, Liang J, Lai D, Guan W, Xu G. Using vacuum-assisted ureteral access sheath in the treatment of complex steinstrasse. Urolithiasis. 2023 Jun 22;51(1):89. doi: 10.1007/s00240-023-01462-2.
PubMed 37347309Zhang Z, Xie T, Li F, Wang X, Liu F, Jiang B, Zou X, Zhang G, Yuan Y, Xiao R, Wu G, Qian B. Comparison of traditional and novel tip-flexible suctioning ureteral access sheath combined with flexible ureteroscope to treat unilateral renal calculi. World J Urol. 2023 Dec;41(12):3619-3627. doi: 10.1007/s00345-023-04648-w. Epub 2023 Oct 11.
PubMed 37821778Nao T, Iga R, Yoshimura R, Kurano Y, Yamamoto S, Tamura K. A new method for effective use of the ClearPetra ureteral access sheath for a giant ureteral stone. Urol Case Rep. 2023 Oct 23;51:102599. doi: 10.1016/j.eucr.2023.102599. eCollection 2023 Nov.
PubMed 38024505Gauhar V, Traxer O, Castellani D, Sietz C, Chew BH, Fong KY, Hamri SB, Gokce MI, Gadzhiev N, Galosi AB, Yuen SKK, El Hajj A, Ko R, Zawadzki M, Sridharan V, Lakmichi MA, Corrales M, Malkhasyan V, Ragoori D, Soebhali B, Tan K, Chai CA, Tursunkulov AN, Tanidir Y, Persaud S, Elshazly M, Kamal W, Tefik T, Shrestha A, Tiong HC, Somani BK. Could Use of a Flexible and Navigable Suction Ureteral Access Sheath Be a Potential Game-changer in Retrograde Intrarenal Surgery? Outcomes at 30 Days from a Large, Prospective, Multicenter, Real-world Study by the European Association of Urology Urolithiasis Section. Eur Urol Focus. 2024 Dec;10(6):975-982. doi: 10.1016/j.euf.2024.05.010. Epub 2024 May 24.
PubMed 38789313
Study at a glance
From the registry record, last updated by the sponsor on 8 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Comparison of the Efficacy and Safety of Vacuum-Assisted and Conventional Ureteral Access Sheath in Retrograde Intrarenal Surgery: A Randomized Controlled Prospective Multicenter Study
- ClinicalTrials.gov ID
- NCT06684756
- Acronym / sponsor ID
- 2024.288.10.16
- Conditions
- Kidney Calculi, Kidney Stones
- Keywords
- kidney stone, retrograde intrarenal surgery, ureteral access sheath, vacuum assisted
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 150 participants (estimated)
- Lead sponsor
- Namik Kemal UniversityUniversity, hospital or other
- Study start
- 1 Oct 2024 (actual)
- Primary completion
- 1 Oct 2025 (actual)
- Study completion
- 1 Dec 2026 (estimated)
- First posted
- 12 Nov 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study aims to compare the efficacy and safety, the ratio of stone-free rates, and complications of two types of access sheaths used in retrograde intrarenal surgery to treat upper urothelial stones. The access sheath types are those with vacuum aspiration and the conventional ones.
Detailed description
The use of ureteral access sheath (UAS) during Retrograde Intrarenal Surgery (RIRS) has been proven effective and reliable in recent years, and publications indicate that it reduces stone-free rates (SFR). Their use is also recommended in the European Urology Guidelines because it improves image quality, reduces intrarenal pressure, and shortens the operation time. For this reason, it has been routinely used in many RIRS cases. In cases where non-vacuum-assisted UAS is used, fragments during stone fragmentation remain in the kidney, and since it is not possible to remove the stones simultaneously, the image may be distorted, and the operation duration may be prolonged. All these may pave the way for postoperative infectious complications. In addition to non-vacuum-assisted UAS, new UASs with flexible ends and vacuum-assisted aspiration have been introduced in the last few years (ClearPetra). Thanks to the aspiration connected to the system, stone fragments can be removed from the body with negative pressure during stone fragmentation. Continuous circulation prevents bleeding during fragmentation and blurring of the visual field due to stone fragments. In addition, since the stone fragments pass through the edges of the sheath without breaking and are removed, a perfect field of view can be provided. Unlike the classical UAS, the tip is flexible, allowing for the safe removal of lower pole stones. Many studies in the literature compare the success and complications of RIRS in cases where conventional UAS was used and not used. In addition, there are publications related to using the newly introduced aspiration access sheath in percutaneous nephrolithotomy. In retrospective publications on using this UAS in RIRS, it has been shown that stone-free rates, operation time, hemoglobin loss, and postoperative infective complications are more successful on the 1st and 30th postoperative days compared to cases where non-vacuum-assisted UAS was used. There is no randomized controlled prospective publication on this subject. This study aims to compare the complications and stone-free rates of RIRS cases where non-vacuum-assisted UAS and new vacuum-assisted UAS were used.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Patients with conventional UAS being used in their RIRS operations | Active comparator | Procedure: Retrograde intrarenal surgeryThe patient population will be selected from cases determined by randomization and used with UAS without an aspiration (conventional) during RIRS. |
| Patients with vacuum assisted UAS being used in their RIRS operations | Experimental | Procedure: Retrograde intrarenal surgeryThe patient population will be selected from cases determined by randomization and used with UAS with an aspiration and flexible tip, different from the conventional one during RIRS. |
Who may qualify
- Ages
- 18 to 85 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- Patients over 18 years of age
- Patients below 85 years of age
- Patients with 11-13 FR conventional/vacuum-assisted ureteral access sheath (UAS) during retrograde intrarenal surgery
Key exclusion criteria (7 listed)
- Patients with non-sterile preoperative urine culture
- Patients with renal anatomic anomalies
- Patients with a solitary (single) kidney
- Patients with insufficient data
- Patients under the age of 18, above the age of 85
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Retrograde intrarenal surgeryFlexible optic devices and lasers fragment kidney stones during this operation. In this surgery, an ureteral access sheath is recommended to be used. | Procedure or surgery | Patients with conventional UAS being used in their RIRS operations, Patients with vacuum assisted UAS being used in their RIRS operations |
Primary outcome
Stone free rates
Time frame: Stone-free status will be checked by performing a non-contrast abdominal CT scan 1 month after the operation.
Presence/absence of residual fragments in postoperative imaging, if any, diameter of longest axis in mm.
1 secondary outcome
Complication rates
Time frame: Peroperative complication rates will be determined during the operation, and postoperative complications will be re-evaluated during hospitalization before discharge or in the first month after discharge.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 8 Jul 2026.
- Background: PubMed 37347309Wang D, Xu Y, Liu Z, Liang J, Lai D, Guan W, Xu G. Using vacuum-assisted ureteral access sheath in the treatment of complex steinstrasse. Urolithiasis. 2023 Jun 22;51(1):89. doi: 10.1007/s00240-023-01462-2.
- Background: PubMed 37821778Zhang Z, Xie T, Li F, Wang X, Liu F, Jiang B, Zou X, Zhang G, Yuan Y, Xiao R, Wu G, Qian B. Comparison of traditional and novel tip-flexible suctioning ureteral access sheath combined with flexible ureteroscope to treat unilateral renal calculi. World J Urol. 2023 Dec;41(12):3619-3627. doi: 10.1007/s00345-023-04648-w. Epub 2023 Oct 11.
- Background: PubMed 38024505Nao T, Iga R, Yoshimura R, Kurano Y, Yamamoto S, Tamura K. A new method for effective use of the ClearPetra ureteral access sheath for a giant ureteral stone. Urol Case Rep. 2023 Oct 23;51:102599. doi: 10.1016/j.eucr.2023.102599. eCollection 2023 Nov.
- Results publication: PubMed 38789313Gauhar V, Traxer O, Castellani D, Sietz C, Chew BH, Fong KY, Hamri SB, Gokce MI, Gadzhiev N, Galosi AB, Yuen SKK, El Hajj A, Ko R, Zawadzki M, Sridharan V, Lakmichi MA, Corrales M, Malkhasyan V, Ragoori D, Soebhali B, Tan K, Chai CA, Tursunkulov AN, Tanidir Y, Persaud S, Elshazly M, Kamal W, Tefik T, Shrestha A, Tiong HC, Somani BK. Could Use of a Flexible and Navigable Suction Ureteral Access Sheath Be a Potential Game-changer in Retrograde Intrarenal Surgery? Outcomes at 30 Days from a Large, Prospective, Multicenter, Real-world Study by the European Association of Urology Urolithiasis Section. Eur Urol Focus. 2024 Dec;10(6):975-982. doi: 10.1016/j.euf.2024.05.010. Epub 2024 May 24.
- Individual participant dataSharing planned: No
Related trials for Kidney Calculi
Not yet recruiting
Automated Versus Manual Irrigation During Flexible Ureteroscopy
Renal Stone Disease
Not yet recruiting
Optimal Intrarenal Pressure During Flexible Ureteroscopy
Renal Stone Disease
RecruitingObservational study
Stone Clearance With Aspiration vs Other Technologies: a Real-world Evidence Study
Urolithiasis, Stones, Kidney
Not yet recruiting
Intertransverse Process Block Versus Erector Spinae Plane Block for Postoperative Analgesia After Percutaneous Nephrolithotomy
Kidney Stones, Urolithiasis, Hypocitraturia, Pain, Postoperative
Not yet recruiting
Comparison of Smart Pressure-Controlled Flexible Ureteroscopy and Flexible Suction Ureteral Access Sheath-Assisted Flexible Ureteroscopy for 2-3 cm Renal Stones
Kidney Stones
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Cenk M. Yazici, Professor study director
Namik Kemal University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Retrograde intrarenal surgery in people with Kidney Calculi and Kidney Stones, run by Namik Kemal University at 1 site in Turkey (Türkiye).
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 8 Jul 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Turkey (Türkiye). Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Mehmet F. Şahin, Ass. Professor (+905555511871, mfatihsahin@gmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Stone free rates (time frame: Stone-free status will be checked by performing a non-contrast abdominal CT scan 1 month after the operation.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT06684756, which also lists 4 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 8 Jul 2026.