Mini-PNL, RIRS, and ESWL for Treatment of Medium-Sized, High-Density, Non-Lower Pole, Renal Stones

August 13, 2026 updated by: Abul-fotouh Ahmed, Al-Azhar University

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.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

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 Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
253

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Egypt
      • Cairo, Egypt, 11633
        • Urology Department, Al-Azhar University Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Adult patients (both genders)
  • Single non-lower pole renal stone.
  • Stone size: 10-20 mm.
  • Stone density: > 1000 HU.

Exclusion Criteria:

  • Pregnant women.
  • Morbid obesity.
  • Severe orthopaedic deformities.
  • Co-morbidities precluding general anaesthesia or prone positioning.
  • Uncorrectable coagulation disorders.
  • Active urinary tract infection (UTI).
  • 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.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: mini-PNL group
In which PCNL will be performed using miniature nephroscope
Procedure: mini-PNL
PCNL using miniature nephroscope. The procedure will be performed under general or regional anaesthesia under fluoroscopy guidance.
Experimental: RIRS group
In which RIRS will be performed using a flexible ureteroscope
Procedure: RIRS
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.
Experimental: SWL group
In which extracorporeal shock wave lithotripsy will be performed using Dornier lithotripter SII
Procedure: SWL
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.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
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.
as detected by non-contrasted computed tomography 3 months after the intervention procedures.
Complication rate
Time Frame: up to 3 months.
intra- and post-operative complications
up to 3 months.

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Cost of treatment
Time Frame: throughout the study procedure, up to 3 months post-operative.
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.
throughout the study procedure, up to 3 months post-operative.
Patients satisfaction
Time Frame: throughout the study procedure, up to 3 months post-operative
A 5-point scale will be used to assess satisfaction, where 1 is unsatisfied and 5 fully satisfied.
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
A 5-point scale will be used to assess satisfaction, where 1 is unsatisfied and 5 fully satisfied.
throughout the study procedure, up to 3 months post-operative

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Al-Azhar University

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Abul-fotouh Ahmed, MD, Al-Azhar University Hospitals, Cairo, Egypt

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
April 5, 2021

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
June 4, 2024

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
June 4, 2025

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
April 17, 2021

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
April 21, 2021

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
April 23, 2021

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
August 14, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
August 13, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
February 1, 2023

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • Uro_Azhar_11_021

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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