Prestenting and its role in the URS: a study on the advantages it could have in intracorporeal lithotripsy interventions

Ureteroscopy (URS) represents the most used procedure in the treatment of urolithiasis, conversely ureteral stenting before URS is still a topic of scientific discussion. The aim of our study is to evaluate the possible benefits and uses of pre-stenting and if it can be used in the everyday practice. In our retrospective observational study, we collected data of patients undergoing URS for ureteral and renal lithiasis from January 2018 to December 2020 at our Department. Patients were stratified by procedure (ureterolithotripsy or URSL vs retrograde intrarenal surgery or RIRS) and by pre-stenting. We collected the patients' clinical characteristics and the timing of pre-stenting insertion. As outcomes variables, we analyzed the stone free rate (SFR), operating times (OT) and short-term complications. 244 patients were included in the study, 84 had undergone pre-stenting with a mean of 44.3±42.7 days before surgery, while 160 did not. Regarding OT there are no differences in URSL and in the RIRS of stones in the renal pelvis; considering the RIRS of caliceal stones it is observed how the OT are lower in pre-stenting patients undergoing RIRS of caliceal stones (mean 79.29±34.7 vs 91.08±53.8 mins, p=0.1) and in case of multiple caliceal stones (mean 83.24±31.2 vs 103.53±48.6 mins, p=0.1). No differences were reported in the SFR for every URSL subgroups while it is higher in patients undergoing RIRS with a pre-stenting (85% vs 75%, p=0.08). Regarding the short term complications, in the pre-stenting group fewer cases of post-operative pain (20.4% vs 39.6% p<0.02) and hematuria (14.8% vs 28.3% p=0.08) were reported. Our study is in accordance with the indications of guidelines which advise against the routine use of pre-stenting before URS. RIRS deserve a separate evaluation and our study, although considering the routine use of pre-stenting unnecessary, recognize its usefulness in achieving SFR and reducing intraoperative complications.