Renal StoneNCT04856722
Mini-PNL, RIRS, and ESWL for Treatment of Medium-Sized, High-Density, Non-Lower Pole, Renal Stones
A study testing mini-PNL, RIRS and SWL in people with Renal Stone and Percutaneous Nephrolithotomy, run by Al-Azhar University at 1 site in Egypt.
Trial summary
The optimal management of medium-sized renal stones remains quite challenging and continues to be contested. In the present study, the investigators will compare mini-PNL, RIRS and SWL in the treatment of non- lower pole, medium size, high dense renal stones regarding the stone-free rate, the safety of the procedures… Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Renal Stone, Percutaneous Nephrolithotomy, Retrograde Intrarenal Surgery
- What is being tested?
- mini-PNL, RIRS and SWL
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 253 participants
- Where
- 1 siteEgypt
- Study dates
- 5 Apr 2021to 4 Jun 2025
- Phase
- Interventional
- Are there results?
- None posted in the registry
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 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Adult patients (both genders)
- Single non-lower pole renal stone.
- Stone size: 10-20 mm.
- Stone density: > 1000 HU.
Who cannot join
- Pregnant women.
- Morbid obesity.
- Severe orthopaedic deformities.
- Co-morbidities precluding general anaesthesia or prone positioning.
- Uncorrectable coagulation disorders.
- Active urinary tract infection (UTI).
Show all 11Show fewer
- Stone in a calyceal diverticulum.
- Abnormal renal anatomy.
- Urinary tract obstruction distal to the stone.
- Concomitant pathology that needs intervention in the same setting.
- Advanced hydronephrosis.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Mini-PNL, RIRS, and ESWL for Treatment of Medium-Sized, High-Density, Non-Lower Pole, Renal Stones: A Prospective, Randomized, Comparative Study
The optimal management of medium-sized renal stones remains quite challenging and continues to be contested. In the present study, the investigators will compare mini-PNL, RIRS and SWL in the treatment of non- lower pole, medium size, high dense renal stones regarding the stone-free rate, the safety of the procedures, cost, and patients' and surgeon's satisfaction. Eligible patients will be randomly allocated into three equal groups (mini-PNL, RIRS, and SWL). Postoperative, patients will be followed-up by regularly for 3 months. The study parameters will be compared between groups.
Read the detailed description
The treatment options for renal stones 10-20 mm include either extracorporeal shock wave lithotripsy (SWL) or endourology (retrograde intrarenal surgery (RIRS) and percutaneous nephrolithotomy (PNL).
SWL is an attractive treatment option for renal stones because it is non-invasive and more acceptable for the patient and can be done under analgesia, sedation, or minimal anaesthesia. However, the limitation of SWL includes a relatively lower stone-free rate (SFR) and the need for repeated sessions and auxiliary procedures. The SFR after SWL is affected by several factors, including body mass index (BMI), stone size, intrarenal stone location, skin-to-stone distance (SSD), and stone density.
The EAU guidelines put endourology and SWL as two equal options in medium-sized non-lower pole renal stones and did not give special attention to the stone density, which is an important predictor for SWL outcome. Several studies reported that the number of SWL sessions increased with increased stone attenuation value (SAV) and SFR decreased significantly in high-density renal stone.
PNL and RIRS have good SFR compared to SWL but might entail a significant risk of morbidity. The improved fURS instrumentation and lithotripsy technology, and development of the miniaturized PNL technique, may lower the procedure-related complications and mPNL and RIRS an alternative and excellent option for medium-sized and even large renal stones The investigators hypothesize that addressing the stone density factor may give a clear recommendation for medium-sized, high-density renal stones. They expected the superiority for either mPNL or RIRS, regarding SFR, without increased morbidity.
The study aims to compare the outcome of mPNL, RIRS, and SWL for treatment of non-lower pole, high-density renal stones of 10 to 20 mm size.
The study will include adult patients with non-lower pole, high-density (>1000 HU) renal stones of 10 to 20 mm size.
Pre-operatively, patients will be evaluated by medical history taking, physical examination. urinalysis, urine culture, complete blood cell count (CBC), liver function tests, coagulation profile, blood urea nitrogen (BUN), serum creatinine, plain abdominal X-ray and computed tomography for urinary tract (CT-UT), Eligible patients will be randomly divided into 3 equal groups. PNL group, in which PNL procedures will be performed using miniature nephroscope, RIRS group, in which RIRS will be performed using flexible ureteroscope and SWL group, in which SWL procedures will be performed using Dornier Lithotripter.
post-operatively, patients will be followed up regularly, for 3 months. The SFR, complication rate, cost, patients' and surgeon's satisfaction will be evaluated and compared between the three groups using the appropriate statistical tests and analytical program.
- Conditions
- Renal Stone, Percutaneous Nephrolithotomy, Retrograde Intrarenal Surgery, Extracorporeal Shockwave Lithotripsy
- Being tested
- mini-PNL, RIRS, SWL
- Medical subject headings
- Nephrolithiasis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
mini-PNLProcedure or surgery
PCNL using miniature nephroscope. The procedure will be performed under general or regional anaesthesia under fluoroscopy guidance.
RIRSProcedure or surgery
RIRS using flexible ureteroscope. The procedure will be performed under general or regional anaesthesia under fluoroscopy guidance. Holmium Laser lithotripter will be used for stone fragmentation.
SWLProcedure or surgery
SWL using Dornier SII lithotripter. the procedure will be performed under sedoanalgesia, and fluoroscopy will be used for stone localization; for a maximum of 3 SWL session.
| Study group | Role | What they receive |
|---|---|---|
| mini-PNL group | Experimental | In which PCNL will be performed using miniature nephroscope Receives: Procedure: mini-PNL |
| RIRS group | Experimental | In which RIRS will be performed using a flexible ureteroscope Receives: Procedure: RIRS |
| SWL group | Experimental | In which extracorporeal shock wave lithotripsy will be performed using Dornier lithotripter SII Receives: Procedure: SWL |
What is being measured
The primary outcome is the main question the study is designed to answer.
Stone-free rate
Stone free status is defined as no residual renal stone or residual fragment(s) less than 4 mm size.
Measured: as detected by non-contrasted computed tomography 3 months after the intervention procedures.
Complication rate
intra- and post-operative complications
Measured: up to 3 months.
Secondary outcomes (3)
Cost of treatment
The cost of each treatment methods will be estimated, Including the devices, disposable instruments, operating room, bed stay, imaging, laboratory, medications, retreatment and ancillary procedures.
Measured: throughout the study procedure, up to 3 months post-operative.
Patients satisfaction
A 5-point scale will be used to assess satisfaction, where 1 is unsatisfied and 5 fully satisfied.
Measured: throughout the study procedure, up to 3 months post-operative
Surgeon's satisfaction.
A 5-point scale will be used to assess satisfaction, where 1 is unsatisfied and 5 fully satisfied.
Measured: throughout the study procedure, up to 3 months post-operative
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 Apr 2021
- Study start5 Apr 2021
- Primary completion4 Jun 2024
- Study completion4 Jun 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for Renal StoneStudies of the same condition, open and under way.
- More trials run by Al-Azhar UniversityThe sponsor's other registered studies.
- 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
- 253 participants (actual)
Sponsor and investigators
- Lead sponsor
- Al-Azhar University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Abul-fotouh Ahmed, Al-Azhar University
- Investigators
- Abul-fotouh Ahmed, MD, Principal investigator, Al-Azhar University Hospitals, Cairo, Egypt
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04856722
- Sponsor's protocol ID
- Uro_Azhar_11_021
- Status last verified
- Feb 2023
- First submitted
- 17 Apr 2021
- Last updated
- 14 Aug 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Ahmed AF, ElShazly A, Daoud A, Abdelazim H, AlGammal M. Safety and Efficacy of Fluoroscopy-Free Technique During Retrograde Intrarenal Surgery for Renal Stones: A Prospective, Randomized, Controlled, Noninferiority Trial. J Endourol. 2025 Jul;39(7):636-645. doi: 10.1089/end.2025.0120. Epub 2025 May 14.
PubMed 40364776Ahmed AF, Raafat M, ElDamanhory H, Abdelazim H, Soliman A, ElShazly A, Hindawy M, Anwar M, Algammal M, Soliman A, Daoud A. Prospective randomized trial comparing mini-percutaneous nephrolithotomy, retrograde intrarenal surgery, and shock wave lithotripsy for treatment of medium-sized high-density renal stones. Int Urol Nephrol. 2026 Jun;58(6):2025-2035. doi: 10.1007/s11255-025-04928-x. Epub 2025 Dec 12.
PubMed 41385038
Study at a glance
From the registry record, last updated by the sponsor on 14 Aug 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Mini-PNL, RIRS, and ESWL for Treatment of Medium-Sized, High-Density, Non-Lower Pole, Renal Stones: A Prospective, Randomized, Comparative Study
- ClinicalTrials.gov ID
- NCT04856722
- Acronym / sponsor ID
- Uro_Azhar_11_021
- Conditions
- Renal Stone, Percutaneous Nephrolithotomy, Retrograde Intrarenal Surgery, Extracorporeal Shockwave Lithotripsy
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 253 participants (actual)
- Lead sponsor
- Al-Azhar UniversityUniversity, hospital or other
- Study start
- 5 Apr 2021 (actual)
- Primary completion
- 4 Jun 2024 (actual)
- Study completion
- 4 Jun 2025 (actual)
- First posted
- 23 Apr 2021 (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.
The optimal management of medium-sized renal stones remains quite challenging and continues to be contested. In the present study, the investigators will compare mini-PNL, RIRS and SWL in the treatment of non- lower pole, medium size, high dense renal stones regarding the stone-free rate, the safety of the procedures, cost, and patients' and surgeon's satisfaction. Eligible patients will be randomly allocated into three equal groups (mini-PNL, RIRS, and SWL). Postoperative, patients will be followed-up by regularly for 3 months. The study parameters will be compared between groups.
Detailed description
The treatment options for renal stones 10-20 mm include either extracorporeal shock wave lithotripsy (SWL) or endourology (retrograde intrarenal surgery (RIRS) and percutaneous nephrolithotomy (PNL).
SWL is an attractive treatment option for renal stones because it is non-invasive and more acceptable for the patient and can be done under analgesia, sedation, or minimal anaesthesia. However, the limitation of SWL includes a relatively lower stone-free rate (SFR) and the need for repeated sessions and auxiliary procedures. The SFR after SWL is affected by several factors, including body mass index (BMI), stone size, intrarenal stone location, skin-to-stone distance (SSD), and stone density.
The EAU guidelines put endourology and SWL as two equal options in medium-sized non-lower pole renal stones and did not give special attention to the stone density, which is an important predictor for SWL outcome. Several studies reported that the number of SWL sessions increased with increased stone attenuation value (SAV) and SFR decreased significantly in high-density renal stone.
PNL and RIRS have good SFR compared to SWL but might entail a significant risk of morbidity. The improved fURS instrumentation and lithotripsy technology, and development of the miniaturized PNL technique, may lower the procedure-related complications and mPNL and RIRS an alternative and excellent option for medium-sized and even large renal stones The investigators hypothesize that addressing the stone density factor may give a clear recommendation for medium-sized, high-density renal stones. They expected the superiority for either mPNL or RIRS, regarding SFR, without increased morbidity.
The study aims to compare the outcome of mPNL, RIRS, and SWL for treatment of non-lower pole, high-density renal stones of 10 to 20 mm size.
The study will include adult patients with non-lower pole, high-density (>1000 HU) renal stones of 10 to 20 mm size.
Pre-operatively, patients will be evaluated by medical history taking, physical examination. urinalysis, urine culture, complete blood cell count (CBC), liver function tests, coagulation profile, blood urea nitrogen (BUN), serum creatinine, plain abdominal X-ray and computed tomography for urinary tract (CT-UT), Eligible patients will be randomly divided into 3 equal groups. PNL group, in which PNL procedures will be performed using miniature nephroscope, RIRS group, in which RIRS will be performed using flexible ureteroscope and SWL group, in which SWL procedures will be performed using Dornier Lithotripter.
post-operatively, patients will be followed up regularly, for 3 months. The SFR, complication rate, cost, patients' and surgeon's satisfaction will be evaluated and compared between the three groups using the appropriate statistical tests and analytical program.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| mini-PNL group | Experimental | Procedure: mini-PNLIn which PCNL will be performed using miniature nephroscope |
| RIRS group | Experimental | Procedure: RIRSIn which RIRS will be performed using a flexible ureteroscope |
| SWL group | Experimental | Procedure: SWLIn which extracorporeal shock wave lithotripsy will be performed using Dornier lithotripter SII |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- Adult patients (both genders)
- Single non-lower pole renal stone.
- Stone size: 10-20 mm.
- Stone density: > 1000 HU.
Key exclusion criteria (11 listed)
- Pregnant women.
- Morbid obesity.
- Severe orthopaedic deformities.
- Co-morbidities precluding general anaesthesia or prone positioning.
- Uncorrectable coagulation disorders.
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 |
|---|---|---|
| mini-PNLPCNL using miniature nephroscope. The procedure will be performed under general or regional anaesthesia under fluoroscopy guidance. | Procedure or surgery | mini-PNL group |
| RIRSRIRS using flexible ureteroscope. The procedure will be performed under general or regional anaesthesia under fluoroscopy guidance. Holmium Laser lithotripter will be used for stone fragmentation. | Procedure or surgery | RIRS group |
| SWLSWL using Dornier SII lithotripter. the procedure will be performed under sedoanalgesia, and fluoroscopy will be used for stone localization; for a maximum of 3 SWL session. | Procedure or surgery | SWL group |
Primary outcome
Stone-free rate
Time frame: as detected by non-contrasted computed tomography 3 months after the intervention procedures.
Stone free status is defined as no residual renal stone or residual fragment(s) less than 4 mm size.
Complication rate
Time frame: up to 3 months.
intra- and post-operative complications
3 secondary outcomes
Cost of treatment
Time frame: throughout the study procedure, up to 3 months post-operative.
Patients satisfaction
Time frame: throughout the study procedure, up to 3 months post-operative
Surgeon's satisfaction.
Time frame: throughout the study procedure, up to 3 months post-operative
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 14 Aug 2026.
- Background: PubMed 40364776Ahmed AF, ElShazly A, Daoud A, Abdelazim H, AlGammal M. Safety and Efficacy of Fluoroscopy-Free Technique During Retrograde Intrarenal Surgery for Renal Stones: A Prospective, Randomized, Controlled, Noninferiority Trial. J Endourol. 2025 Jul;39(7):636-645. doi: 10.1089/end.2025.0120. Epub 2025 May 14.
- Derived from this study: PubMed 41385038Ahmed AF, Raafat M, ElDamanhory H, Abdelazim H, Soliman A, ElShazly A, Hindawy M, Anwar M, Algammal M, Soliman A, Daoud A. Prospective randomized trial comparing mini-percutaneous nephrolithotomy, retrograde intrarenal surgery, and shock wave lithotripsy for treatment of medium-sized high-density renal stones. Int Urol Nephrol. 2026 Jun;58(6):2025-2035. doi: 10.1007/s11255-025-04928-x. Epub 2025 Dec 12.
- Safety and Efficacy of Fluoroscopy-Free Technique During Retrograde Intrarenal Surgery for Renal Stones: A Prospective, Randomized, Controlled, Noninferiority TrialLink provided by the sponsor.
- Individual participant dataSharing planned: No
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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. This study is not recruiting at the moment.
Abul-fotouh Ahmed, MD principal investigator
Al-Azhar University Hospitals, Cairo, Egypt
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing mini-PNL, RIRS and SWL in people with Renal Stone and Percutaneous Nephrolithotomy, run by Al-Azhar University at 1 site in Egypt.
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 4 inclusion and 11 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: finished, as of the sponsor's last update on 14 Aug 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 Egypt. 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?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Stone-free rate (time frame: as detected by non-contrasted computed tomography 3 months after the intervention procedures.). The study lists 2 primary outcomes in all. 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 NCT04856722, which also lists 2 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 14 Aug 2026.