An observational study in Urolithiasis, Renal Stones and Upper Ureteric Stones, sponsored by Assiut University. Not yet recruiting. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-08-07.
Sponsored by Assiut University · Observational
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:
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.
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:
253 studies on the registry are indexed under Urolithiasis; 67 are open to participants now.
This study's planned enrollment of 70 is below the median of 150 across 65 observational studies indexed under Urolithiasis.
Browse Urolithiasis studies →Assiut University is the lead sponsor of 5,078 studies on the registry; 2,178 are open to participants now.
Of its 14 completed or terminated interventional studies of FDA-regulated products, 0 (0%) have results posted.
Counted across the registry records on this site, refreshed daily.
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.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Stone-Free Rate
Treatment outcome determined through postoperative imaging to document the presence and size of any residual stone fragments.
Time frame: 4 weeks post-procedure
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.
Time frame: 4 weeks post-procedure
No study locations are listed for this record.
This study is not yet recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.