Impact of Ureteral Stent and Sheaths Size on Post-Operative Pain

Inclusion Criteria: • Patients undergoing a retrograde intra-renal surgery (RIRS) (only patients undergoing the procedure for stone treatment will be included) who will require post-operative indwelling ureteral stent placement on a string at the conclusion of the procedure. Exclusion Criteria: * Patients with intra-operative ureteral injury who will require ureteral stent for extended time (more than 10 days, in that case a stent without a string will be used). * Patient undergoing ureteroscopy for any indication other than stone extraction. * Patients who are currently pregnant as determined by clinical presurgical screening.