Comparison Between Ureterorenoscopy With Lithotripsy Alone Versus Combination With Hydrogel for Kidney Stone Removal

Inclusion Criteria: * Male or female subjects aged ≥ 18 years * Evidence of nephrolithiasis on presentation of a preoperative computer tomography (CT) scan not older than 6 months * Minimum size of the kidney stones defined as \>10mm in the longest axis in the preoperative CT. * Ability to read, write and speak German * Women of childbearing age must have a negative serum pregnancy test at the start of the study. * Submission of a personally signed and dated informed consent form stating that the subject has been informed of all relevant aspects of the study prior to any trial-related activity and that all information has been understood Exclusion Criteria: * Participation in another clinical trial for kidney stone removal in the last 6 months * Subjects with gastrointestinal cancer who have not been in remission for at least 2 years * Subjects with a single kidney, horseshoe kidney or other anatomical abnormalities that may increase the risk of surgery for the subject * Subjects with untreated ureteral stenosis or renal stenosis and narrow ureteropelvic junction/ureterovesical junction * Subjects with known impaired renal function from stage IV or known dialysis * Subjects with chronic hydronephrosis not associated with nephrolithiasis * Subjects with the following known or suspected diseases: Coagulation disorders, untreated urinary tract infections, renal disease sepsis and marked prostatic hyperplasia * Subjects with any other disease or condition that, in the opinion of the investigator, could interfere with the purpose of the study (e.g. bleeding that restricts vision in the kidney, problems in the renal tubular system) * Breastfeeding or pregnant women * Subjects who may be part of a vulnerable group (e.g. prisoners or developmentally delayed adults)