1Haifler M1,2, Weiss D3, Winkler H1, Ramon J1, Einav S 3, Kleinmann N Malignant ureteral obstruction relieved by stiff tandem ureteral stents 1Haifler M1,2, Weiss D3, Winkler H1, Ramon J1, Einav S 3, Kleinmann N 1 Department of Urology, Chaim Sheba medical center 2 OMNI research group, Department of biomedical engineering, Tel Aviv University 3 Cardiovascular System and Bioengineering Laboratory, Department of biomedical engineering Intro Aim Material and methods Results Conclusions

Introduction Malignant ureteral obstruction (MUO) usually portends poor prognosis Many of these cases are refractory to standard ureteral stent drainage The gold standard draining method : PCN PCN drainage is accompanied by a significant impairment in quality of life1 1 Scand J Urol. 2014 Dec 1:1-7 Intro

Introduction Tandem ureteral stents (TUS) may enhance flow through the obstructed ureter by: Providing additional scaffold Allowing for extra-luminal flow through the space between the stents1 Using a stiff stent provides adequate drainage and lower renal pelvis pressure2 1 Urology 2002;59:594–596. 2 J Urol. 1992 Aug;148(2 Pt 1):278-80. Intro

Introduction Artificial and computational models imply on TUS drainage superiority. Intro

Aim To examine the effect of stiff TUS drainage of MUO on clinical parameters Intro Aim

Material and methods The use of stiff TUS drainage began in June 2014 Surgical technique: Retrograde pyelogram A 4cm/18F ureteral balloon dilation catheter (20 atmospheres) 14F ureteral dilator Two double pigtail stiff ureteral stents were placed under fluoroscopy Intro Aim Material and methods

Material and methods Data collected: Gender Age Type of primary tumor Side Obstruction site Obstruction length Failure (need for PCN) Indication for drainage Creatinine prior/post drainage Hydronephrosis prior/post drainage Intro Aim Material and methods

Material and methods 14 patients / 22 renal units (ru) were drained between 6/2014 – 4/2015 Median age – 55y (IQR 35-65) M/F – 6/8 patients Intro Aim Material and methods Results

Results Indication for drainage: Renal failure – 14 ru PCN discomfort – 3 ru Sepsis – 2 ru Flank pain – 2 ru Type of primary tumor : Gastrointestinal – 5 pt Genitourinary – 3 pt Gynecological – 5 pt Lymphoma – 1 pt Intro Aim Material and methods Results

Results 2 month post tandem TUS drainage 1 month prior to tandem TUS drainage Intro Aim Material and methods Results

Results Improvement in renal failure occurred in 86% of patients Follow-up period – 24 w (IQR 11-30) Failure – 8 (38.1%) All failures occurred due to urosepsis Median time to failure – 16 w Intro Aim Material and methods Results

Conclusions Most patients benefit from TUS drainage Failure occurs after several weeks in the minority of patients Further prospective trials should delineate the role of this type of drainage technique in this clinical scenario Intro Aim Material and methods Results Conclusions

THANK YOU! Intro Aim Material and methods Results Conclusions