NCT07601932 · Icahn School of Medicine at Mount Sinai
Patient Positioning for Treatment of Proximal Ureteral Stones
What this study is about
Ureteroscopic management of proximal ureteral stones presents technical challenges including stone retropulsion, prolonged operative time, and conversion to intrarenal treatment. Reverse Trendelenburg positioning has been shown to reduce proximal stone migration and operative time in ureteral stones, while the T-tilt position improves intrarenal stone clearance.
View original scientific description
Ureteroscopic management of proximal ureteral stones presents technical challenges including stone retropulsion, prolonged operative time, and conversion to intrarenal treatment. Reverse Trendelenburg positioning has been shown to reduce proximal stone migration and operative time in ureteral stones, while the T-tilt position improves intrarenal stone clearance. The optimal strategy for proximal ureteral stones (treating stones in situ using reverse Trendelenburg versus pushing stones into the kidney followed by intrarenal treatment in T-tilt) remains unknown. This randomized controlled trial compares these two strategies, with primary focus on operative time as a measure of procedural efficiency. A total of 54 patients (27 per arm) will be enrolled at Mount Sinai West.
Interventions
PROCEDURE
Reverse Trendelenburg Position
Patients will be positioned in reverse Trendelenburg at a 20 degree incline with the use of a digital protractor. Lithotripsy will be performed within the ureter with attempts to prevent proximal migration and until all fragments are removed.
PROCEDURE
T-Tilt Position
Stone will be intentionally relocated into the kidney when feasible, followed by intrarenal lithotripsy in T-tilt position. In the T-tilt position the table is angled 15-degree Trendelenburg and 15-degree airplane away from the surgical side kidney with the use of a digital protractor. This allows fragments to rest in a superior and medial position away from the lower pole to facilitate removal.
Primary outcome measures
Total operative time
Time frame: Immediately postoperatively on the day of surgery
Operative time will be used to compare procedural efficiency
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Adults aged 18 years and older.
- Diagnosed with kidney stones and scheduled for fURS.
- Stone burden \> 1 cm and/or multiple stones will be eligible.
- Able and willing to provide informed consent.
Exclusion criteria
- Pregnant persons as determined by pre-operative urine pregnancy test (standard of care at the institution)
- Untreated UTI
- Patients with urinary anomalies (e.g., urinary diversion, ureteral reconstruction, horseshoe kidney)
- Single stone \< 1 cm
Where
- New York, New York
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jun 4, 2026 · Source of record for eligibility and locations