Multi-Center Phase II Study of the Clinical Use of the Avicenna Roboflex

Abstract

Objectives: To present the results of a multicentric phase-II study, representing the next step according to the IDEAL-criteria in the evualuation process of robot-assisted flexible ureterorenocopy. Material and methods: The Avicenna Roboflex consists of a console and the manipulator. Peri-operative data from 266 patients who underwent robotic retrograde intra-renal stone surgery (robRIRS) between January 2015 and March 2016 at two centres (Heilbronn, Ankara) were recorded prospectively. Six surgeons were involved in the study. We treated 90 females and 176 male patients with a mean age of 55 (2576) years. 118 stones were located on the right and 148 on the left side. Mean number of stones was 1.8 with a mean stone burden of 1620 (98-10600)mm3; 43% of the patients were pre-stented. A 12/14F access sheath was used in all cases; laser fragmentation was accomplished by a high-energy laser device applying actual concepts of laser lithotripsy. Results: Preparation of the robot required 4:30min (range 3-8min); docking time was 4 min (range 1-29min). Console time to identify the stone amounted 4min (range 1-12min.); total operating time was 96 min (range 58-193min) including a console time of 65(16-174) min. Laser lithotripsy was performed in 245 patients (92%), 112(42%) patients required extraction of larger fragments using N-gage-basket. The stone clearance rate amounted 25(9-101)mmA3/min. Total fluoroscopy time was time 2:30min with a radiation dosis of 297 cGy*cm2. 117(44%) of our patients were stented post-operatively of which 75(28%) had the stent on a string removed on day 1 together with the Foley catheter. In 2(0.7%) cases we had to convert to classical FURS due to technical failure of the robot. Median post-operative hospital stay was 1(1-30) day. We encountered one case of urosepsis (Clavien 3a) requiring treatment on an intensive care unit.