Which Patinets Benefit More From Percutaneous Nephrolithotomy? A Location-Based Comparative Analysis of PCNL and RIRS for 1-2 cm Renal Stones

May 10, 2026 updated by: Esra DOĞAN YILMAZ, PhD, Kırıkkale University
This prospective randomized controlled trial aims to compare the clinical efficacy and safety of Percutaneous Nephrolithotomy (PCNL) and Retrograde Intrarenal Surgery (RIRS) for renal stones measuring 10-20 mm. The study specifically investigates whether the anatomical location of the stone (upper, middle, or lower calyx) influences the success rates and stone-free outcomes of these two surgical modalities. A total of 110 patients were randomized into two equal groups to evaluate primary endpoints, including stone-free rates at the 3-month follow-up, and secondary endpoints such as operative time and complication rates

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

n this prospective randomized controlled trial, 110 adult patients diagnosed with a single non-staghorn renal stone measuring 10-20 mm were enrolled. The study was conducted at Kırıkkale High Specialization Hospital between the specified study dates. Participants were randomized in a 1:1 ratio into two treatment arms: Percutaneous Nephrolithotomy (PCNL) and Retrograde Intrarenal Surgery (RIRS). Randomization was implemented using a computer-generated sequence to ensure unbiased allocation.

The primary objective is to compare the stone-free rates (SFR) between the two surgical techniques at the 3-month postoperative mark, as confirmed by non-contrast computed tomography. A secondary and key focus of the study is the impact of stone localization (upper, middle, and lower calyx) on the success of each procedure. Additional outcomes evaluated include total operative time, hospital stay duration, hemoglobin level changes, and postoperative complication rates according to the Clavien-Dindo classification system. The results aim to provide a location-based surgical selection framework for mid-sized renal stones.

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.
110

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

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

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

Patients aged 18 years or older. Presence of a single, non-staghorn radiopaque renal stone measuring 10-20 mm in diameter.

Stone location in the upper, middle, or lower renal calyx. Patients who provided written informed consent.

Exclusion Criteria:

Patients with untreated urinary tract infections or urosepsis. Patients with uncorrected bleeding disorders or receiving anticoagulant therapy.

Presence of severe skeletal deformities preventing surgical positioning. Patients with morbid obesity (BMI > 40 kg/m²). Presence of anatomical abnormalities (e.g., horseshoe kidney, ectopic kidney). Pregnancy. Multiple renal stones or stones larger than 20 mm

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: PCNL Group
Patients in this group underwent Percutaneous Nephrolithotomy (PCNL) for the treatment of renal stones measuring 10-20 mm. The procedure was performed in the prone or lithotomy position under general anesthesia.
Device: Percutaneous Nephrolithotomy (PCNL)
A standard percutaneous approach was used. Under general anesthesia, a nephrostomy tract was established, and the stone was fragmented using a pneumatic or ultrasonic lithotripter.
Active Comparator: RIRS Group
Patients in this group underwent Retrograde Intrarenal Surgery (RIRS) using a flexible ureterorenoscope and laser lithotripsy for the treatment of renal stones measuring 10-20 mm.
Device: Retrograde Intrarenal Surgery (RIRS)
The procedure was performed using a flexible ureterorenoscope. Stones were fragmented using a Holmium:YAG laser fiber after reaching the renal pelvis and calyces retrogradely.

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 (SFR)
Time Frame: 3 months postoperatively
The percentage of patients who are completely free of stones or have only clinically insignificant residual fragments (less than 3 mm). This will be evaluated using non-contrast computed tomography (NCCT)
3 months postoperatively

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
Total Operative Duration
Time Frame: During the surgical procedure (intraoperative)
The time from the initial incision or insertion of the endoscope until the completion of the procedure and dressing, measured in minutes
During the surgical procedure (intraoperative)
Change in Hemoglobin Levels
Time Frame: Within 24 hours postoperatively.
The difference between preoperative and postoperative hemoglobin levels to assess blood loss.
Within 24 hours postoperatively.
Postoperative Complications
Time Frame: From surgery up to 30 days postoperatively.
The frequency and severity of complications classified according to the Clavien-Dindo classification system
From surgery up to 30 days postoperatively.
Length of Hospital Stay
Time Frame: From the day of surgery until hospital discharge (typically 1-3 days).
The total number of days the patient remained in the hospital following the procedure.
From the day of surgery until hospital discharge (typically 1-3 days).

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.
Kırıkkale University

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.
May 1, 2012

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.
September 15, 2013

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.
November 1, 2013

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).
May 10, 2026

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.
May 10, 2026

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.
May 15, 2026

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.
May 15, 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.
May 10, 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.
May 1, 2026

More Information

Terms related to this study

Keywords

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.
  • 12/14-06

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.

Clinical Trials on Kidney Calculi Nephrolithiasis Urolithiasis Renal Stone

Clinical Trials on Percutaneous Nephrolithotomy (PCNL)

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings