UrolithiasisNCT07566741
A Prospective Analysis of Thulium Fiber Laser Efficiency
A study testing thulium fiber laser lithotripsy in people with Urolithiasis, run by Bozok University at 1 site in Turkey (Türkiye).
Trial summary
Patients diagnosed with urolithiasis will be prospectively enrolled in this study. Preoperative diagnostic assessment will be performed using computed tomography (CT). Key parameters, including stone dimensions, quantity, total stone burden, and stone density (Hounsfield units), will be evaluated preoperatively. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Urolithiasis
- What is being tested?
- thulium fiber laser lithotripsy
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 61 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 1 Jun 2025to 31 Jan 2026
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- aged 18 years and above
- diagnosed with symptomatic urinary system stones
- planned URS or fURS
- normal upper urinary tract anatomy
- achieved stone-free
Who cannot join
- active urinary tract infection
- history of surgery/DJ stent placement within the last six months
- congenital renal anomalies
- patients with residual fragments on postoperative evaluation
Trial locations and contacts
1 site in 1 country.
Turkey (Türkiye)1 site
Yozgat Bozok University Faculty of Medicine
Yozgat, Yozgat, 66100
About this study
Official title: A Prospective Analysis of Thulium Fiber Laser Efficiency: How Stone Volume and Density Predict Intraoperative Energy Consumption
Patients diagnosed with urolithiasis will be prospectively enrolled in this study. Preoperative diagnostic assessment will be performed using computed tomography (CT). Key parameters, including stone dimensions, quantity, total stone burden, and stone density (Hounsfield units), will be evaluated preoperatively. This study aims to analyze data from patients who undergo ureteroscopic Thulium Fiber Laser (TFL) lithotripsy and achieve a stone-free status within a single procedural session. Based on these data, a 'Specific Energy Coefficient' will be derived to enable the preoperative prediction of the total laser energy required for successful lithotripsy.
Read the detailed description
This prospective observational trial investigated the correlation between Thulium Fiber Laser (TFL) energy consumption and stone characteristics. Adult patients (≥18 years) with symptomatic urinary stones indicated for (f)URS and normal upper tract anatomy were included. Only patients achieving a complete stone-free status in a single session were analyzed. Exclusion criteria comprised active urinary tract infection, history of ipsilateral surgery or stent placement within six months, congenital renal anomalies, and postoperative residual fragments. Stone parameters were evaluated via non-contrast computed tomography (NCCT, 1.0 mm slice thickness). Mean stone density was measured in Hounsfield Units (HU) using a representative region of interest (ROI). Stone volume (V) was calculated using the validated ellipsoid formula. Procedures were performed by two high-volume endourologists using a 200 µm Thulium fiber. Semirigid URS (7.5-9.5 F) or flexible URS (7.5 F) with an access sheath (10/12-12/14 F) were utilized based on stone location. All cases employed "Dusting Mode" (0.1-0.2 J; 80-150 Hz). Laser ablation time was recorded from the initial firing until complete visual stone clearance/dusting. The primary outcome was the derivation of the Specific Energy Coefficient, calculated by dividing the total energy by the product of stone volume and density. Data were analyzed using SPSS v26.0. Normality was assessed via Shapiro-Wilk/Kolmogorov-Smirnov tests. Descriptive data were reported as mean ± standard deviation or median. Spearman's correlation and Multiple Linear Regression were used to identify independent predictors of laser energy requirements, with the model's predictive power reported as adjusted R2. Statistical significance was set at p < 0.05.
- Conditions
- Urolithiasis
- Being tested
- thulium fiber laser lithotripsy
- Keywords
- urolithiasis, thulium fiber laser, lithotripsy, steno-free, energy
- Medical subject headings
- Urolithiasis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
thulium fiber laser lithotripsyProcedure or surgery
Procedures were performed by two high-volume experienced endourologists. Semirigid URS (7.5-9.5 F) was utilized for ureteral stones, while flexible URS (7.5 F) with a ureteral access sheath (10/12 F or 12/14 F) was preferred for renal stones. A 200 µm Thulium fiber was employed in all cases. Fragmentation was performed in Dusting Mode (Pulse Energy: 0.1-0.2 J, Frequency: 80-150 Hz).
| Study group | Role | What they receive |
|---|---|---|
| Stone-free | Experimental | Not described Receives: Procedure: thulium fiber laser lithotripsy |
What is being measured
The primary outcome is the main question the study is designed to answer.
thulium fiber laser energy consumption per mm3xHu
Measured: 4 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted5 May 2026
- Study start1 Jun 2025
- Primary completion31 Jan 2026
- Study completion31 Jan 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for UrolithiasisStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 61 participants (actual)
Sponsor and investigators
- Lead sponsor
- Bozok University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Volkan Selmi, Bozok University
- Investigators
- volkan selmi, Principal investigator, Yozgat Bozok University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07566741
- Sponsor's protocol ID
- 2025-GOKAEK-2513
- Status last verified
- May 2026
- First submitted
- 28 Apr 2026
- Last updated
- 8 May 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Selmi V, Oztekin U, Caniklioglu M, Isikay L. Prediction of The Energy Required for Ho:YAG Laser Lithotripsy of Urinary Stones. Urol J. 2021 Apr 28;18(3):284-288. doi: 10.22037/uj.v18i.6442.
PubMed 33931845
Study at a glance
From the registry record, last updated by the sponsor on 8 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Prospective Analysis of Thulium Fiber Laser Efficiency: How Stone Volume and Density Predict Intraoperative Energy Consumption
- ClinicalTrials.gov ID
- NCT07566741
- Acronym / sponsor ID
- 2025-GOKAEK-2513
- Conditions
- Urolithiasis
- Keywords
- urolithiasis, thulium fiber laser, lithotripsy, steno-free, energy
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 61 participants (actual)
- Lead sponsor
- Bozok UniversityUniversity, hospital or other
- Study start
- 1 Jun 2025 (actual)
- Primary completion
- 31 Jan 2026 (actual)
- Study completion
- 31 Jan 2026 (actual)
- First posted
- 5 May 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Patients diagnosed with urolithiasis will be prospectively enrolled in this study. Preoperative diagnostic assessment will be performed using computed tomography (CT). Key parameters, including stone dimensions, quantity, total stone burden, and stone density (Hounsfield units), will be evaluated preoperatively. This study aims to analyze data from patients who undergo ureteroscopic Thulium Fiber Laser (TFL) lithotripsy and achieve a stone-free status within a single procedural session. Based on these data, a 'Specific Energy Coefficient' will be derived to enable the preoperative prediction of the total laser energy required for successful lithotripsy.
Detailed description
This prospective observational trial investigated the correlation between Thulium Fiber Laser (TFL) energy consumption and stone characteristics. Adult patients (≥18 years) with symptomatic urinary stones indicated for (f)URS and normal upper tract anatomy were included. Only patients achieving a complete stone-free status in a single session were analyzed. Exclusion criteria comprised active urinary tract infection, history of ipsilateral surgery or stent placement within six months, congenital renal anomalies, and postoperative residual fragments. Stone parameters were evaluated via non-contrast computed tomography (NCCT, 1.0 mm slice thickness). Mean stone density was measured in Hounsfield Units (HU) using a representative region of interest (ROI). Stone volume (V) was calculated using the validated ellipsoid formula. Procedures were performed by two high-volume endourologists using a 200 µm Thulium fiber. Semirigid URS (7.5-9.5 F) or flexible URS (7.5 F) with an access sheath (10/12-12/14 F) were utilized based on stone location. All cases employed "Dusting Mode" (0.1-0.2 J; 80-150 Hz). Laser ablation time was recorded from the initial firing until complete visual stone clearance/dusting. The primary outcome was the derivation of the Specific Energy Coefficient, calculated by dividing the total energy by the product of stone volume and density. Data were analyzed using SPSS v26.0. Normality was assessed via Shapiro-Wilk/Kolmogorov-Smirnov tests. Descriptive data were reported as mean ± standard deviation or median. Spearman's correlation and Multiple Linear Regression were used to identify independent predictors of laser energy requirements, with the model's predictive power reported as adjusted R2. Statistical significance was set at p < 0.05.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Stone-free | Experimental | Procedure: thulium fiber laser lithotripsy |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- aged 18 years and above
- diagnosed with symptomatic urinary system stones
- planned URS or fURS
- normal upper urinary tract anatomy
- achieved stone-free
Key exclusion criteria (4 listed)
- active urinary tract infection
- history of surgery/DJ stent placement within the last six months
- congenital renal anomalies
- patients with residual fragments on postoperative evaluation
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| thulium fiber laser lithotripsyProcedures were performed by two high-volume experienced endourologists. Semirigid URS (7.5-9.5 F) was utilized for ureteral stones, while flexible URS (7.5 F) with a ureteral access sheath (10/12 F or 12/14 F) was preferred for renal stones. A 200 µm Thulium fiber was employed in all cases. Fragmentation was performed in Dusting Mode (Pulse Energy: 0.1-0.2 J, Frequency: 80-150 Hz). | Procedure or surgery | Stone-free |
Primary outcome
thulium fiber laser energy consumption per mm3xHu
Time frame: 4 weeks
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 8 May 2026.
- Background: PubMed 33931845Selmi V, Oztekin U, Caniklioglu M, Isikay L. Prediction of The Energy Required for Ho:YAG Laser Lithotripsy of Urinary Stones. Urol J. 2021 Apr 28;18(3):284-288. doi: 10.22037/uj.v18i.6442.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
volkan selmi principal investigator
Yozgat Bozok University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing thulium fiber laser lithotripsy in people with Urolithiasis, run by Bozok University at 1 site in Turkey (Türkiye).
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 8 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Turkey (Türkiye). Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
thulium fiber laser energy consumption per mm3xHu (time frame: 4 weeks). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07566741, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 8 May 2026.