UrolithiasisNCT07753096
Predicting the Success of Flexible Ureterorenoscopy for Kidney and Upper Ureter Stones
An observational study of Urolithiasis and Renal Stones, run by Assiut University.
Trial summary
This observational study aims to test how well a specific medical scoring tool, called a nomogram, can predict the success of a common minimally invasive surgery for kidney stones. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Urolithiasis, Renal Stones, Upper Ureteric Stones
- How many people
- 70 participants
- Where
- No sites listed yet
- Study dates
- Sep 2026to Oct 2027
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
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
- Adult, Older adult
Study population: The study population consists of adult patients, aged 18 years and older, of both sexes who present with renal or upper ureteric stones. These patients must be scheduled to undergo flexible ureterorenoscopy (fURS) as part of their standard clinical management. Participants will be drawn from the patient population receiving routine care at the Urology Department of Assiut University Hospitals.
Who may be able to join
- Adult patients (≥18 years).
- Both sexes.
- Patients with renal stones.
- Patients with upper ureteric stones.
- Patients scheduled for flexible ureterorenoscopy.
- Patients willing to provide informed consent.
Who cannot join
- Congenital urinary tract anomalies.
- Active urinary tract infection.
- Pregnancy.
- Patients with incomplete clinical or radiological data.
- Patients lost to follow-up.
About this study
Official title: Validation of a Nomogram for Prediction of Success of Flexible Ureterorenoscopy for Treatment of Renal and Upper Ureteric Stones
This observational study aims to test how well a specific medical scoring tool, called a nomogram, can predict the success of a common minimally invasive surgery for kidney stones. The surgery being studied is flexible ureterorenoscopy (fURS), which is widely used to treat stones in the kidney and the upper part of the ureter. In this study, procedural success is defined as a patient being completely stone-free after their surgery.
While fURS is highly effective, the chances of completely clearing all stones can vary from person to person based on individual factors like stone size, stone volume, and anatomical characteristics. Researchers want to determine if this nomogram can accurately estimate a patient's personalized chance of achieving a stone-free outcome before the intervention takes place.
Read more
Participants in this study will be adult patients who are already scheduled to undergo fURS as part of their standard medical care. Because this is an observational study, there are no experimental treatments, participants will receive their normal surgical care.
During the study, the research team will collect standard clinical information, including:
- Preoperative data such as age, body mass index (BMI), blood tests, and CT scan results.
- Operative details during the surgery, such as the time it takes, the experience level of the surgeon, and the laser settings used to break up the stones.
- Postoperative outcomes, specifically reviewing follow-up imaging to check for the presence and size of any remaining stone fragments.
By comparing the nomogram's preoperative predictions to the patients' actual surgical results, the researchers hope to validate the tool's accuracy. Confirming the reliability of this tool could help doctors better plan individualized treatments, avoid unnecessary procedures, and improve how they counsel future patients regarding their expected surgical outcomes.
Read the detailed description
Urolithiasis remains one of the most common urological diseases globally, characterized by increasing incidence and recurrence rates. While flexible ureterorenoscopy (fURS) has become a preferred minimally invasive treatment for renal and upper ureteric stones due to its high efficacy and low morbidity, the stone-free rate (SFR) varies significantly among patients. To optimize patient counseling and treatment selection, predictive nomograms have emerged as practical tools that integrate multiple clinical and radiological variables into a single, individualized probability estimate for achieving stone clearance.
However, external validation is a critical prerequisite before adopting any predictive model into routine clinical practice. A nomogram developed in one population may exhibit different predictive accuracy in another due to variations in patient characteristics, stone burden, and local healthcare settings. Currently, there is limited evidence regarding the performance of published fURS predictive models in Middle Eastern and Egyptian populations. This study addresses this gap by conducting an independent external validation of a published nomogram at Assiut University Hospitals.
The study involves a comprehensive, multi-phase data collection process for all enrolled participants:
- Preoperative Assessment: Patients will undergo clinical, laboratory, and radiological evaluations. Baseline demographic data (age, sex, body mass index) and serum creatinine levels will be recorded. Stone characteristics will be evaluated using computed tomography (CT) to document stone size, volume, number, location, laterality, and the presence of hydronephrosis. CT findings specifically required to calculate the nomogram score will be systematically extracted.
- Intraoperative Parameters: During the fURS procedure, the surgical team will prospectively record the total operative time, utilization of a ureteral access sheath, specific laser lithotripsy settings utilized for fragmentation, the operating surgeon's experience level, and any intraoperative complications encountered.
- Postoperative Evaluation: Following the surgery, researchers will document the duration of the hospital stay, any postoperative complications, and the potential need for auxiliary procedures (such as repeat ureteroscopy, shock wave lithotripsy, or percutaneous interventions for residual stone burden).
- Keywords
- Flexible Ureterorenoscopy, fURS, Nomogram, Upper Ureteric Stones, Renal Stones, Urolithiasis
- Medical subject headings
- Urolithiasis, Nephrolithiasis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Patients Undergoing Flexible Ureterorenoscopy (fURS) | This cohort consists of adult patients (18 years and older) of both sexes diagnosed with renal or upper ureteric stones who are scheduled to undergo flexible ureterorenoscopy (fURS) as part of their routine clinical management. Preoperative characteristics, intraoperative parameters, and postoperative outcomes will be prospectively recorded to validate a predictive nomogram for determining stone-free status. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Stone-Free Rate
Treatment outcome determined through postoperative imaging to document the presence and size of any residual stone fragments.
Measured: 4 weeks post-procedure
Secondary outcomes (1)
Predictive Accuracy of the Nomogram
The discrimination ability of the nomogram to accurately predict stone-free status after the procedure, evaluated using the Area Under the Receiver Operating Characteristic (AUC-ROC) curve.
Measured: 4 weeks post-procedure
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted7 Aug 2026
- Study startSep 2026 (estimated)
- Primary completionSep 2027 (estimated)
- Study completionOct 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for UrolithiasisStudies of the same condition, open and under way.
- More trials run by Assiut UniversityThe sponsor's other registered studies.
- 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
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 70 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Assiut University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Abdelrahman Sayed Abdelrehim Abdelaziz, Assiut University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07753096
- Sponsor's protocol ID
- fURS Success Nomogram Validity
- Status last verified
- Aug 2026
- First submitted
- 4 Aug 2026
- Last updated
- 7 Aug 2026
- Results posted
- No
Study at a glance
From the registry record, last updated by the sponsor on 7 Aug 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Validation of a Nomogram for Prediction of Success of Flexible Ureterorenoscopy for Treatment of Renal and Upper Ureteric Stones
- ClinicalTrials.gov ID
- NCT07753096
- Acronym / sponsor ID
- fURS Success Nomogram Validity
- Keywords
- Flexible Ureterorenoscopy, fURS, Nomogram, Upper Ureteric Stones, Renal Stones, Urolithiasis
- Study type
- Observational
- Recruitment status
- Not yet recruiting
- Enrolment
- 70 participants (estimated)
- Lead sponsor
- Assiut UniversityUniversity, hospital or other
- Study start
- Sep 2026 (estimated)
- Primary completion
- Sep 2027 (estimated)
- Study completion
- Oct 2027 (estimated)
- First posted
- 7 Aug 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.
This observational study aims to test how well a specific medical scoring tool, called a nomogram, can predict the success of a common minimally invasive surgery for kidney stones. The surgery being studied is flexible ureterorenoscopy (fURS), which is widely used to treat stones in the kidney and the upper part of the ureter. In this study, procedural success is defined as a patient being completely stone-free after their surgery.
While fURS is highly effective, the chances of completely clearing all stones can vary from person to person based on individual factors like stone size, stone volume, and anatomical characteristics. Researchers want to determine if this nomogram can accurately estimate a patient's personalized chance of achieving a stone-free outcome before the intervention takes place.
Participants in this study will be adult patients who are already scheduled to undergo fURS as part of their standard medical care. Because this is an observational study, there are no experimental treatments, participants will receive their normal surgical care.
During the study, the research team will collect standard clinical information, including:
- Preoperative data such as age, body mass index (BMI), blood tests, and CT scan results.
- Operative details during the surgery, such as the time it takes, the experience level of the surgeon, and the laser settings used to break up the stones.
- Postoperative outcomes, specifically reviewing follow-up imaging to check for the presence and size of any remaining stone fragments.
By comparing the nomogram's preoperative predictions to the patients' actual surgical results, the researchers hope to validate the tool's accuracy. Confirming the reliability of this tool could help doctors better plan individualized treatments, avoid unnecessary procedures, and improve how they counsel future patients regarding their expected surgical outcomes.
Detailed description
Urolithiasis remains one of the most common urological diseases globally, characterized by increasing incidence and recurrence rates. While flexible ureterorenoscopy (fURS) has become a preferred minimally invasive treatment for renal and upper ureteric stones due to its high efficacy and low morbidity, the stone-free rate (SFR) varies significantly among patients. To optimize patient counseling and treatment selection, predictive nomograms have emerged as practical tools that integrate multiple clinical and radiological variables into a single, individualized probability estimate for achieving stone clearance.
However, external validation is a critical prerequisite before adopting any predictive model into routine clinical practice. A nomogram developed in one population may exhibit different predictive accuracy in another due to variations in patient characteristics, stone burden, and local healthcare settings. Currently, there is limited evidence regarding the performance of published fURS predictive models in Middle Eastern and Egyptian populations. This study addresses this gap by conducting an independent external validation of a published nomogram at Assiut University Hospitals.
The study involves a comprehensive, multi-phase data collection process for all enrolled participants:
- Preoperative Assessment: Patients will undergo clinical, laboratory, and radiological evaluations. Baseline demographic data (age, sex, body mass index) and serum creatinine levels will be recorded. Stone characteristics will be evaluated using computed tomography (CT) to document stone size, volume, number, location, laterality, and the presence of hydronephrosis. CT findings specifically required to calculate the nomogram score will be systematically extracted.
- Intraoperative Parameters: During the fURS procedure, the surgical team will prospectively record the total operative time, utilization of a ureteral access sheath, specific laser lithotripsy settings utilized for fragmentation, the operating surgeon's experience level, and any intraoperative complications encountered.
- Postoperative Evaluation: Following the surgery, researchers will document the duration of the hospital stay, any postoperative complications, and the potential need for auxiliary procedures (such as repeat ureteroscopy, shock wave lithotripsy, or percutaneous interventions for residual stone burden).
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Patients Undergoing Flexible Ureterorenoscopy (fURS) | – | –This cohort consists of adult patients (18 years and older) of both sexes diagnosed with renal or upper ureteric stones who are scheduled to undergo flexible ureterorenoscopy (fURS) as part of their routine clinical management. Preoperative characteristics, intraoperative parameters, and postoperative outcomes will be prospectively recorded to validate a predictive nomogram for determining stone-free status. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Age groups
- Adult, Older adult
- Study population
- The study population consists of adult patients, aged 18 years and older, of both sexes who present with renal or upper ureteric stones. These patients must be scheduled to undergo flexible ureterorenoscopy (fURS) as part of their standard clinical management. Participants will be drawn from the patient population receiving routine care at the Urology Department of Assiut University Hospitals.
Key inclusion criteria (6 listed)
- Adult patients (≥18 years).
- Both sexes.
- Patients with renal stones.
- Patients with upper ureteric stones.
- Patients scheduled for flexible ureterorenoscopy.
Key exclusion criteria (5 listed)
- Congenital urinary tract anomalies.
- Active urinary tract infection.
- Pregnancy.
- Patients with incomplete clinical or radiological data.
- Patients lost to follow-up.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Stone-Free Rate
Time frame: 4 weeks post-procedure
Treatment outcome determined through postoperative imaging to document the presence and size of any residual stone fragments.
1 secondary outcome
Predictive Accuracy of the Nomogram
Time frame: 4 weeks post-procedure
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 7 Aug 2026.
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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.
The record lists no contact. Use the official record to reach the sponsor.
Questions about this trial
What is this clinical trial studying?
An observational study of Urolithiasis and Renal Stones, run by Assiut University.
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 6 inclusion and 5 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: opening soon, as of the sponsor's last update on 7 Aug 2026. Status can change between updates, so confirm with the study contact before making plans.
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?
This study is still under way. Results are not available in the source record yet.
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?
Stone-Free Rate (time frame: 4 weeks post-procedure). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 7 Aug 2026.