In this study, authors evaluated risk factors of failure of UAS deployment during flexible ureteroscopy (URS).
Authors performed a retrospective single center study. A total of 480 consecutive patients undergoing URS for renal stones between January 2010 and January 2016 were enrolled. Three different types of UAS were used during the study including coaxial (Flexor regular, Cook Medical) and two parallels (Flexor Parallel, Cook and ReTrace, Coloplast). Patient demographics and clinical characteristics and peri-and postoperative data were collected and univariate and multivariate analysis was performed.
Of those 480 patients the failure rate was 8.6%. Sixty-four percent of ureters (379 patients) were pre-stented. Study demonstrated that independent predictive factors of deployment failure were: Non-pre-stented ureters (OR=36, p<0.0001), the absence of previous fURS (OR=4.5, p=0.02), and the use of Flexor® Parallel™ UAS (OR=7.1, p<0.0001). Age at surgery, gender, body masse index, side of surgery and length of UAS (35cm vs 45cm) were not associated with failure.
In conclusion, the study demonstrated that the failure rate in patients undergoing URS who were pre-stented is minimal. Insertion of a 12/14F UAS before RIRS failed in 8.6% of patients. The non-pre-stented status, the absence of previous fURS, the absence of srURS before fURS and the use of Flexor Parallel (Cook) UAS were significantly associated with failure of UAS insertion. If patients are planned to undergo URS with deployment of UAS, they must be pre-stented and the size of UAS must be carefully selected.
Speaker(s): Dr. Forzini, MD
Authors: Forzini T.1, Lecuelle D.1, Alezra E.1, Becquart N.1, Haraux E.2, Saint F.1, De Sousa P.1
at the #EAU17 - March 24-28, 2017- London, England