Comparison of irrigation flows between different irrigation methods for flexible ureteroscopy: An in vitro study.

OBJECTIVE: To compare the irrigation flows between different irrigation methods for f-URS. METHODS: We compared the automatic irrigation system Endoflow II to gravity-based irrigation, and gravity-based irrigation with pressure cuff. Irrigation pressures were set at 40 and 100cmH2O. A LithoVue f-URS with a 3.6Fr working channel was used for the experiments. The f-URS was placed in straight alignment without active deflection on the operating table. For each irrigation pressure level, we evaluated the influence of the occupation of the working channel of the f-URS with an empty working channel, a 272µm laser fiber, a 1.9Fr nitinol basket. The outflow from f-URS was measured by the volume of irrigation fluid collected using a graduated glass at 1min, 2min, 3min and 5min. RESULTS: Irrigations flows remained constant over the time for the Endoflow II and the gravity-based irrigation methods regardless of the irrigation pressure and setting. For the pressure cuff method, the irrigation flow remained constant only when the working channel was occupied either by the nitinol basket or the laser fiber. Irrigation flow with the Endoflow II were constantly higher than gravity-based irrigation methods. Irrigation flow significantly increased with increased irrigation pressure. In the presence of any instruments at any irrigation pressure, the flow decreased as the size of the instrument in the working channel increased. CONCLUSIONS: Automatic irrigation system Endoflow II provided higher irrigation flows than gravity-based irrigation methods. The irrigation flow decreased as the size of the instrument in the working channel increased. Further studies conducted in vivo are needed to investigate if the differences found between irrigation methods result in higher intrarenal pressure during procedures. LEVEL OF PROOF: 4.

[Urethro-vesical anastomosis reconstruction using extra-peritoneal robot-assisted laparoscopy for anastomotic stenosis after radical prostatectomy]. / Réfection d'anastomose urétro-vésicale par voie extra-péritonéale laparoscopique robot-assistée pour sténose anastomotique post-prostatectomie radicale.

INTRODUCTION: Urethro-vesical anastomosis stenosis following radical prostatectomy is a rare complication but represents a challenging situation. While the first-line treatment is endoscopic, recurrences after urethrotomies require a radical approach. We present the updated results of our patient's cohort treated by pure robotic anastomosis refection. MATERIAL AND METHODS: This is a retrospective, single-center study focusing on one surgeon's experience. Patients presented an urethro-vesical stricture following a radical prostatectomy. Each patient received at least one endoscopic treatment. The procedure consisted of a circumferential resection of the stenosis, followed by a re-anastomosis with well-vascularized tissue. We reviewed the outcomes in terms of symptomatic recurrences and continence after the reconstructive surgery. RESULTS: From April 2013 to May 2020, 8 patients underwent this procedure. Half of the patients had previously been treated with salvage radio-hormonotherapy. The median age was 70 years (64-76). The mean operative time was 109minutes (60-180) and blood loss was 120cc (50-250). One patient had an early postoperative complication, with vesico-pubic fistula. The average length of stay was 4.6 days (3-8). Mean follow-up was 24.25 months (1-66). Half of the patients experienced a recurrence at a median time of 8.25 months (6-11) after surgery. Five patients experienced incontinence of which 3 required an artificial urinary sphincter implantation. CONCLUSION: Extra-peritoneal robot-assisted urethro-vesical reconstruction is feasible and safe to manage bladder neck stricture after radical prostatectomy. The risk of postoperative incontinence is high, justifying preoperative information. LEVEL OF EVIDENCE: III.