Reduction of Stent Associated Morbidity by Minimizing Stent Material.

Reduction of Stent Associated Morbidity by Minimizing Stent Material: A Prospective Randomized Single-blind Study Assessing a Novel "Suture-Stent".

After providing informed consent, patients will be randomized into one of two groups (single-blinded): Group 1 will receive a standard Percuflex® (Boston scientific) ureteral stent. Diameter: 6F, length according to surgeons' estimation. Patients in Group 2 will receive a Suture-Stent adjusted to the individual stone location.

All participant receive standardized patient information, using a validated leaflet on ureteral stenting and associated morbidity.

In both groups, patients will complete the Ureteral Stent Symptoms Questionnaire (USSQ) 1 week after stent insertion, prior to stent removal (i.e. 2-6 weeks after insertion) and after (2-6 weeks) stent removal. USSQ results after stent removal serve as an assessment of "baseline symptoms". During secondary stone removal, stents are removed and ureteral dilatation / access is assessed.

The removed stents will be assessed for biofilm formation within the framework of an approved and ongoing study on the development of a Biofilm-model (EKSG 15/084). Potential complications and adverse events are assessed at all scheduled and unscheduled patient visits.

Inclusion Criteria:

• Kidney stone(s) and/or ureteral stone(s) at the iliacal vessel crossing of the ureter or proximally
• Indication for ureteral stenting for the preparation of a secondary intervention
• Informed consent

Exclusion Criteria:

• Patients younger than 18 years
• Bilateral ureteral stenting
• Stenting because of malignant obstruction
• Mentally retarded patients
• Obstructive pyelonephritis at the time of stent insertion
• Additional operations performed during the stent indwelling time