Double J ureteral stents (DJ) are widely used in urological practice and commonly inserted after most of ureteroscopies. Stent-related symptoms (SRS) represent a major issue. Many research lines have been explored with the aim of decreasing SRS: Vogt et al. projected a self-made pigtail suture stent (PSS) replacing the distal pigtail with a 0.3 Fr suture reaching the bladder, showing decreased SRS and good tolerance. To date, these promising results hasn't been confirmed by a prospective randomized controlled trial (RCT) involving a marketed PSS. Thus, we designed a prospective single-blind RCT to compare SRS caused by marketed PSS and conventional DJ after uncomplicated URS for stone treatment.

Inclusion Criteria:

• ureteral or renal stones < 2 cm needing treatment through semirigid or flexible URS and laser lithotripsy
• stone-free procedure and absence of intraprocedural complications
• WHO performance status 0-2

Exclusion Criteria:

• significant residual fragments at the end of the procedure
• intraprocedural complications (e.g. ureteral damage or stricture)
• indwelling double J stent
• acute kidney failure
• urinary tract infection
• urinary tract abnormalities
• pathologies or medications potentially influencing voiding pattern and pain perception