Comparison Between Ureterorenoscopy With Lithotripsy Alone Versus Combination With Hydrogel for Kidney Stone Removal
NCT Number: NCT06469736
Status: NOT_YET_RECRUITING
Study Type: INTERVENTIONAL
Phases: NA
Conditions: Nephrolithiasis|Lithotripsy, Laser|Ureteroscopy
Interventions: PROCEDURE: Standard of Care Ureterorenoscopy|PROCEDURE: Standard of Care Ureterorenoscopy with MediNiK
Sponsor: Technical University of Munich
Sex: ALL
Age: ADULT, OLDER_ADULT
Enrollment: 120
Study Design: Allocation: RANDOMIZED|Intervention Model: CROSSOVER|Masking: NONE|Primary Purpose: TREATMENT
Start Date: 2024-06-20
Completion Date: 2026-06-30
Locations: University Hospital rechts der Isar, Munich, Bavaria, 81675, Germany

Summary:
The incidence of kidney stones (urolithiasis) has surged in both developing and developed countries, affecting approximately 15% of the global population. From 2010 to 2019, diagnoses of kidney and ureteral stones rose by 8% in Germany, 26% in France, and 15% in England. Correspondingly, the number of surgical stone removal procedures increased by 3%, 38%, and 18%, respectively. Common treatments include extracorporeal shock wave lithotripsy (ESWL), ureterorenoscopy (URS) with lithotripsy, and percutaneous nephrolithotomy (PCNL).

URS, depending on stone size, has become a preferred method due to advancements in intraoperative imaging and laser technology. Despite these improvements, small fragments often remain post-intervention, leading to recurrent stones. Complete removal of all fragments is crucial to significantly reduce recurrence rates. Current literature suggests a high recurrence rate with residual fragments, impacting healthcare costs and patient quality of life.

A key objective in endourological research is optimizing the stone clearance rate. Techniques like coagulum lithotomy and the autologous blood clot technique have been developed to enhance residual stone removal after laser fragmentation. These methods benefit selected patients but are not widely adopted due to complications such as reduced intraoperative visibility and long coagulum formation times.

Recently, a two-component hydrogel system called mediNiK® (Purenum GmbH, Germany) was developed. This biocompatible gel can be applied through an endoscope after stone fragmentation and large fragment retrieval to embed smaller fragments and dust, forming a removable conglomerate. MediNiK® has demonstrated effectiveness in embedding and removing stone residues and is already in clinical use in Europe, showing potential for optimizing stone removal.

A multicenter study has assessed the safety and tolerability of mediNiK® in standard URS (Open, randomized, multicentre study to evaluate the safety, tolerability, and performance of mediNiK® compared to standard treatment in kidney stone removal - DRKS00030532). Results indicate the gel is safe and tolerable. However, further data from larger cohorts and comparisons with conventional URS are necessary before widespread adoption of mediNiK®.

Primary Outcome Measures: Stone free Rate after URS, To answer the primary research question, a comparison of the SFR between the two surgical procedures is planned using the chi-square test. In order to be able to show a statistically significant difference with regard to the surgical procedures according to the current data situation (75 % vs. 95 %), a sample size of 120 was defined with a power of 80 % and a significance level of 0.025 (the significance correction is made due to the definition of two co-primary endpoints in relation to the definition of freedom from stones)., From enrollment to postoperative follow-up at 2 months.
Secondary Outcome Measures: Surgery Duration, • Duration of surgery (minutes, continuous): defined as the time from transurethral entry with the cystoscope to ureteral stent insertion in the affected kidney), During the procedure|Laser duration, • Laser duration (minutes, continuous): defined as the time until the stone is sufficiently dusted, during the procedure|Basketing duration, • Basketing duration (minutes, continuous): defined as the time until the fragments are completely captured and removed, during the procedure|Complication, • Complication rates according to Clavien Dindo (I-IV); the type and number (%) are recorded, after the procedure up to 1 month|Subjective assessment of the operation by the surgeon, • Subjective assessment of the operation by the surgeon via questionnaire (Likert scales, 1-5): Difficulty 1 (easy) - 5 (very difficult) ,Stone-free 1(no stones) - 5 (2nd look necessary), During the procedure|Cost, Costs (euros): defined as the costs of hospitalization, surgery, outpatient care and emergency presentation in euros per patient, From enrollment to postoperative follow-up at 12 months|Frequency of a stone-related event, Frequency of a stone-related event (defined as an event related to stone treatment, %): Repeat operation: DJ blocked (yes, no), completion of URS in case of residual stone (yes, no), repeat URS in case of stone recurrence (yes, no, side), DJ in case of new stone formation (yes, no, side, type), New stone formation: stone recurrence (yes, no, side), colic (yes, no, side), new imaging (yes, no, type), From enrollment to postoperative follow-up at 3 months.