Ureteroscopic Lithotripsy for Renal Stones Using a Sheathless Approach or Using a Flexible and Navigable Ureteral Access Sheath (FANS)

NCT07741084 | Not Yet Recruiting DMC

• 1 other identifier: 992079
• Study Type: interventional
• Target: 225
• Locations: 1 country
• Sites: 1

Brief Summary

The primary aim of the study is to compare stone free rates following ureteroscopic (URS) lithotripsy for renal stones with Thulium Fiber Laser (TFL) using a sheathless approach (low power laser settings) or using a flexible and navigable ureteral access sheath (FANS) with either low power or high power laser settings. Secondary aims are to compare the results of sheathless- and FANS assisted URS lithotripsy in terms of operative time, laser time, intraoperative and postoperative complications. Following the primary comparison between sheathless and FANS groups, another aim is to compare the outcome of low power and high power URS lithotripsy in the FANS patients with respect to operative time, SFR, laser time, intraoperative and postoperative complications. Patients ≥ 18 years with renal stones (8-25 mm) scheduled for URS lithotripsy at the Day Surgery Clinic at Haukeland University Hospital in Bergen, Akershus University Hospital and The Hospital of Vestfold - all renal stone centres in Norway, are eligible for inclusion in the study. After written consent and inclusion, patients are randomised to laser lithotripsy using one of three alternative ureteroscopic approaches: Group 1: Sheathless URS using low power TFL 4 -10 Watts, short pulse mode, Group 2: URS with FANS using low power TFL 4 - 10 Watts, short pulse mode or Group 3: URS with FANS using high power TFL 16 - 24 Watts, short pulse mode. The ureteroscopic procedures are performed in general anaesthesia using a standardised technique. All patients are followed up with a low dose CT scan 3 months post endoscopically to assess stone free status as well as a consultation at the outpatient clinic. Results and data for the three randomisation groups are compared according to the aims of the study.

Conditions

Renal Stones

Keywords

URS lithotripsy; TFL; Sheatless URS; FANS; low power laser settings; high power laser settings

Outcome Measures

Primary Outcomes (1)

• Stone free rate

  Assessment of stone free status (or the presence of residual fragments) on low dose CT 3 months post endoscopically

  3 months post endoscopically

Secondary Outcomes (4)

• Operative time

  During surgery (approximately 1 hour), registered immediately after surgery

• Laser activation patterns: active laser time

  During surgery (approximately 1 hour), registered immediately after surgery

• Intraoperative complications

  During surgery (approximately 1 hour), registered immediately after surgery

• Postoperative complications

  After surgery until 3 months post endoscopically

Other Outcomes (5)

• Operative time, FANS low power vs FANS high power

  During surgery (approximately 1 hour), registered immediately after surgery

• Stone free rate, FANS low power vs FANS high power

  3 months post endoscopically

• Laser activation patterns: active laser time, FANS low power vs FANS high power

  During surgery (approximately 1 hour), registered immediately after surgery

Study Arms (3)

Group 1 - Sheathless URS, low power

EXPERIMENTAL

Sheathless URS using low power laser settings (4-6W), short pulse: 0.4 - 0.5J at 10 or 20Hz, or 0.6 - 0.8J at 10Hz

Procedure: Sheathless URS

Group 2 - FANS, low power

EXPERIMENTAL

URS with FANS using low power laser settings (4-6W), short pulse: 0.4 - 0.5J at 10 or 20Hz, or 0.6 - 0.8J at 10Hz

Procedure: FANS, low power

Group 3 - FANS, high power

EXPERIMENTAL

URS with FANS using high laser power (16-24W), short pulse: 0.4 - 0.5J at 40Hz, 0.6J at 30 - 40Hz, or 0.8J at 20 - 30Hz

Procedure: FANS, high power

Interventions

Sheathless URS PROCEDURE

Sheathless URS using low laser power (4-6W), short pulse: 0.4 - 0.5J at 10 or 20Hz, or 0.6 - 0.8J at 10Hz. Standard start-up settings: 0.4J/10Hz (4W)

Group 1 - Sheathless URS, low power

FANS, low power PROCEDURE

Sheathless URS using low laser power (4-6W), short pulse: 0.4 - 0.5J at 10 or 20Hz, or 0.6 - 0.8J at 10Hz. Standard start-up settings: 0.6J/10Hz (6W)

Group 2 - FANS, low power

FANS, high power PROCEDURE

URS with FANS using high laser power (16-24W), short pulse: 0.4 - 0.5J at 40Hz, 0.6J at 30 - 40Hz, or 0.8J at 20 - 30Hz. Standard start-up settings: 0.4J/40Hz (16W)

Group 3 - FANS, high power

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients ≥ 18 years scheduled for URS lithotripsy for renal stones, 8-25 mm, at the day surgery unit at Haukeland University Hospital, Akershus University Hospital and The Hospital of Vestfold

You may not qualify if:

• Concomitant ureteral stone
• Urinary diversion
• Active infection
• Untreated cancer in the upper urinary tract

Sponsors & Collaborators

• Haukeland University Hospital: lead
• University Hospital, Akershus: collaborator
• The Hospital of Vestfold: collaborator

Study Sites (1)

Haukeland University Hospital

Bergen, Vestland, 5021, Norway

Location

Related Publications (2)

• AEsoy MS, Juliebo-Jones P, Gjengsto P, Beisland C, Ulvik O. Watt's the difference? A randomised trial of high- vs low-power ureteroscopic thulium fibre laser lithotripsy. BJU Int. 2026 Mar;137(3):485-492. doi: 10.1111/bju.70123. Epub 2025 Dec 22.

  PMID: 41429432 BACKGROUND

• Ulvik O, AEsoy MS, Juliebo-Jones P, Gjengsto P, Beisland C. Thulium Fibre Laser versus Holmium:YAG for Ureteroscopic Lithotripsy: Outcomes from a Prospective Randomised Clinical Trial. Eur Urol. 2022 Jul;82(1):73-79. doi: 10.1016/j.eururo.2022.02.027. Epub 2022 Mar 14.

  PMID: 35300888 BACKGROUND

MeSH Terms

Conditions

Nephrolithiasis

Condition Hierarchy (Ancestors)

Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases; Urolithiasis; Male Urogenital Diseases

Study Officials

• Øyvind Ulvik

  Haukeland University Hospital

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Øyvind Ulvik, MD, PhD, Professor

CONTACT

+4790918595; doc.ulvik@online.no

Mathias S Æsøy, MD, PhD

CONTACT

mathias.asoy@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Masking Details: Stone free status is assessed on low dose CT 3 months post endoscopically by an outcome assessor blinded to the randomisation.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: The patients are randomised to ureteroscopic stone treatment with Thulium Fiber Laser with either a sheathless approach and low power laser settings, the use of FANS and low power laser settings or the use of FANS and high power laser settings. The ureteroscopic procedures are performed in a standardised manner and follow-up is similar in all three groups.

Study Record Dates

• First Submitted: July 28, 2026
• First Posted: August 3, 2026
• Study Start (Estimated): August 15, 2026
• Primary Completion (Estimated): March 31, 2027
• Study Completion (Estimated): June 30, 2027
• Last Updated: August 3, 2026

Record last verified: 2026-07

Data Sharing

• IPD Sharing: Will not share

Locations

NO (1)