Loop-tail stents fail in reducing stent-related symptoms. Results of a prospective randomized controlled trial.

Abstract

PURPOSE\nTo compare stent-related symptoms (SRS) of loop-tail (LT) stents and conventional double J (DJ) stents after uncomplicated flexible ureteroronescopy (RIRS), in a prospective randomized controlled single-blind parallel-group study.\n\n\nMATERIALS AND METHODS\nPatients undergoing RIRS were randomized into two groups: group LT received loop-tail stents (Polaris ™ Loop), group DJ received conventional double J stents (Vortek ® ). Stent was removed after 4 weeks. Ureteral Stent Symptom Questionnaire (USSQ) was submitted after 2 days, 4 weeks and 8 weeks (baseline evaluation). Primary endpoint was to compare Urinary Symptom Index Score of LT group versus DJ 4 weeks after RIRS. Secondary endpoints were to compare USSQ domains subscores 2 days and 4 weeks after RIRS, USSQ single answers at 4 weeks, and 4 weeks USSQ domains subscores adjusted for baseline.\n\n\nRESULTS\n68 patients were randomized (34 LT and 34 DJ). 4 weeks answers showed no significant differences concerning Urinary Symptom Index Score (p=0.982), Pain Index Score (p=0.169), VAS (p=0.276) and all the other domains of USSQ. 4 weeks single answer analysis didn t find any difference between the two groups: urinary symptoms were all comparable; the same for pain requiring painkillers (p=0.684) and pain during sex (p=0.496). As to 2 days answers, no significant differences were noticed considering every single domain score. The same applies to USSQ subscores at 4 weeks adjusted for 8 weeks baseline results, which were also comparable.\n\n\nCONCLUSIONS\nThe study found no differences in terms of SRS between LT and DJ group, both 2 days and 4 weeks after stent insertion, with or without baseline correction.