Comparing Efficiency and Stone-Free Rates Mini PCNL vs Flex URS

NCT ID: NCT07072598

Last Updated: 2025-12-02

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

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Recruitment Status

NOT_YET_RECRUITING

Clinical Phase

NA

Total Enrollment

80 participants

Study Classification

INTERVENTIONAL

Study Start Date

2025-12-31

Study Completion Date

2026-12-31

Brief Summary

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The objective of the study is to compare the stone free rates with ureteroscopy utilizing the ClearPETRA suction ureteral access sheath, and mini-PCNL; both procedures and ClearPETRA sheaths are standard of care and are used regularly for stone treatment. Our primary objective is to assess the complete stone free rate with both procedures.

Detailed Description

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With the advent of mini-PCNLs, some endourologists have been utilizing the technique to treat renal calculi up to 3cm in size with better stone free rates and similar comorbidity compared to ureteroscopy. These procedures require percutaneous renal access, and it is associated with greater length of stay and fluoroscopy time.

The ClearPETRA ureteral access sheath has shown great promise with improving stone free rates, decreasing intra-renal pressure and delivering some of the benefits of mini-PCNL without the added risk associated with obtaining percutaneous renal access.

The ClearPETRA flexible suction ureteral access sheath anecdotally improves efficiency and allows endourologists to better clear stone debris when compared to traditional ureteral access sheaths. We have yet to see a comparison between suction ureteral access sheaths and mini-PCNL with the suction renal access sheath.

Study Hypothesis: Compared to traditional access sheaths, using ClearPETRA access sheaths will result in an improvement in stone free rates with both modalities, with lower complications. Using ClearPETRA access sheaths in both modalities compared to traditional access sheaths should result in less of a difference in stone free rates between the ureteroscopy group and the mini-PCNL group.

Conditions

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Kidney Stones Nephrolithiasis Urolithiasis

Study Design

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Allocation Method

RANDOMIZED

Intervention Model

PARALLEL

Primary Study Purpose

TREATMENT

Blinding Strategy

NONE

Study Groups

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Ureteroscopy

Patients randomized to this arm will have their stones treated using the method of Ureteroscopy in a standardized fashion. A second 0.035in sensor guidewire will then be advanced up to the renal pelvis with placement confirmed by fluoroscopy. Placement of a 12/14Fr ClearPETRA ureteral access sheath will be attempted. If this is unsuccessful, a 11/13Fr ClearPETRA ureteral access sheath will be advanced over the wire. If this is unsuccessful, a 5Fr open ended ureteral catheter will be placed and procedure will be converted to a miniPCNL. Lithotripsy will be performed with the MOSES 2.0 high power Holmium laser with settings of 0.3J and 120Hz or 2J and 20Hz depending on stone location and appearance. Stones will be extracted with the suction access sheath. A ureteral stent will be placed at the conclusion of the procedure.

Group Type ACTIVE_COMPARATOR

ClearPETRA suction access sheath

Intervention Type DEVICE

Ureteroscopy utilizing the ClearPETRA suction access sheath.

Mini-PCNL

Will be performed by first starting with supine flexible cystoscopy to cannulate the ureteral orifice with a 5Fr open ended ureteral catheter. The patient will then be repositioned prone with 1-2 bumps placed transversely across the chest. Contrast will be instilled into the ureteral catheter and renal access will be obtained fluoroscopically with the triangulation technique. Once access is obtained, the tract will be dilated to 20Fr and a 18/20Fr ClearPETRA renal access sheath will be inserted to assess the collecting system. If there is concern that the 20Fr access is not sufficient to clear the stone, the tract will be upsized to 24 or 30Fr. The stones will be evacuated with the Trilogy Lithotripter and/or laser, suction and/or basket extraction. A ureteral stent will be placed at the conclusion of the procedure.

Group Type ACTIVE_COMPARATOR

ClearPETRA suction access sheath

Intervention Type DEVICE

Mini-PCNL utilizing the ClearPETRA suction access sheath

Interventions

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ClearPETRA suction access sheath

Ureteroscopy utilizing the ClearPETRA suction access sheath.

Intervention Type DEVICE

ClearPETRA suction access sheath

Mini-PCNL utilizing the ClearPETRA suction access sheath

Intervention Type DEVICE

Eligibility Criteria

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Inclusion Criteria

* Patients 18 years or older
* Have a CT scan showing renal stones 1-3cm in length
* Patients who will be able to read, understand, and complete patient questionnaires

Exclusion Criteria

* Pregnant individuals
* Those with anomalous renal anatomy
* Patients with a urinary diversion (ex: Ileal conduit, reservoir, bladder substitute, etc.)
* Any condition rendering patient medically unfit to undergo either procedure (Bleeding diasthesis)
* Patients who lack decisional capacity
* Patients who are non-english speakers\*

* Non-recruitment of non-english speakers is due to the study being a small pilot study that is used to assess the stone free rate for patients treated with a ureteroscopy or mini-PCNL using ClearPETRA suction access sheaths in a small portion of our patient population seeking treatment for stones. The team also does not possess the bandwidth or personnel to consent patients who are non-English speaking.
Minimum Eligible Age

18 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

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KARL STORZ Endoscopy-America, Inc.

INDUSTRY

Sponsor Role collaborator

Northwestern University

OTHER

Sponsor Role lead

Responsible Party

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Amy Krambeck

Director of the Endourology/Stone Division

Responsibility Role PRINCIPAL_INVESTIGATOR

Locations

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Northwestern Memorial Hospital

Chicago, Illinois, United States

Site Status

Countries

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United States

Central Contacts

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Alyssa McDonald, MPH

Role: CONTACT

312-695-8146

Allaa Fadl-Alla, BA

Role: CONTACT

312-695-8146

Facility Contacts

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Alyssa McDonald, MPH

Role: primary

312-695-8146

Allaa Fadl-Alla

Role: backup

312-695-8146

Other Identifiers

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STU00222993

Identifier Type: -

Identifier Source: org_study_id

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