Flexible Ureteroscopy Versus Mini-Percutaneous Nephrolithotomy for Treatment of Renal Stones

Flexible Ureteroscopy Versus Mini-Percutaneous Nephrolithotomy for Treatment of Renal Stones 2 Cm or Less; A Randomised, Comparative Study.

Management of nephrolithiasis is evolving rapidly, and various minimally-invasive urological procedures are currently available for treating patients with renal stones, including extracorporeal shockwave lithotripsy (ESWL), flexible ureteroscopy (f-URS) and miniaturised percutaneous nephrolithotomy (mini-PCNL).

Despite being the only truly-non-invasive, outpatient procedure, stone-free rates (SFRs) of ESWL are lower than both mini-PCNL and f-URS. Furthermore, ESWL has several limitations, such as pregnancy; uncorrected coagulopathy;aortic aneurism; severe obesity; large stone burdens (>2cm); stones with high densities (>970/1000 Hounsfield units); ESWL-resistant stone compositions; lower calyceal stones with unfavourable anatomical criteria; and stones in calyceal diverticula; Morbidities of the conventional PCNL are significantly minimised by using less access diameters in PCNL while providing comparable SFRs. Additionally, Mini and Micro PCNL result in shorter hospital stay and higher tubeless rates compared to conventional PCNL.

Flexible ureteroscopy has been increasingly used as a primary modality for treatment of renal stones with significantly lower complication rates than PCNL and mini-PCNL in terms of less bleeding and transfusion rates, shorter hospital stay and less postoperative pain. Additionally, f-URS is the only treatment modality of nephrolithiasis that can be safely and effectively used in patients with bleeding tendency, as well as pregnant women; moreover, its outcomes are not affected by obesity. Nevertheless, its poor durability and high costs remain major limitations for f-URS, especially in developing countries.

Study Overview

• Status: Completed
• Conditions: Stone;Renal
• Intervention / Treatment: Procedure: Flexible ureteroscopy; Procedure: mini-Percutaneus nephrolithotomy

• Study Type: Observational
• Enrollment (Actual): 118

Contacts and Locations

Study Locations

• Egypt
  • Asyut Governorate
    • Asyut, Asyut Governorate, Egypt, 71515
      • Assiut Urology and Nephrology Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years to 70 years (Child, Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

no specific criteria

Description

Inclusion Criteria:

• Age above than 15 years
• Renal stone(s) with total burden of 2 cm or less
• Signature on written, informed consents with the details of this study requirements.
• Inappropriateness or failure of ESWL (examples of ESWL inappropriateness: patient preference; distal obstruction; contraindications of ESWL)

Exclusion Criteria:

• Uncorrectable bleeding diathesis
• Current pregnancy

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
f-URS	Procedure: Flexible ureteroscopy; The procedure will be performed in an endourology room where a radiolucent operative table together with a C-arm, a video-camera unit and a Laser device are available. Irrigation fluids include normal saline and/or sterile water.; Other Names: RIRS; f.URS; Retrograde Intrarenal Surgery
mini-PCNL	Procedure: mini-Percutaneus nephrolithotomy; The procedure is done in the prone position under fluoroscopy guidance with a semi-rigid 12Fr. Nephroscope; Other Names: Mini-perc; Mini-PCNL; m.PCNL

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
initial stone clearance	Number of participants who has been totally cleared of stones as measured by KUB and ultrasound	24 hours after the operation
final stone clearance	Number of participants who has been totally cleared of stones as measured by non-contrast CT	90 days after the operation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Operative time	time passed during the operation	Within 24 hours
Hospital stay	Number of days the patient has been hospitalised	Within a week from the operation
Haemoglobin drop	The percentage of haemoglobin drop before and after the operation	within 24 hours

Collaborators and Investigators

• Sponsor: Assiut University

Study record dates

Study Major Dates

• Study Start (Actual): May 27, 2019
• Primary Completion (Actual): July 30, 2021
• Study Completion (Actual): December 27, 2021

Study Registration Dates

• First Submitted: April 27, 2019
• First Submitted That Met QC Criteria: April 27, 2019
• First Posted (Actual): April 30, 2019

Study Record Updates

• Last Update Posted (Estimated): September 30, 2025
• Last Update Submitted That Met QC Criteria: September 24, 2025
• Last Verified: September 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Urogenital Diseases; Male Urogenital Diseases; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Urolithiasis; Nephrolithiasis
• Other Study ID Numbers: NCT03932370

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
• product manufactured in and exported from the U.S.: No