A New Navigation System of Renal Puncture for Endoscopic Combined Intrarenal Surgery: Real-time Virtual Sonography-guided Renal Access

OBJECTIVE To evaluate the clinical utility of a new navigation technique for percutaneous renal puncture using real-time virtual sonography (RVS) during endoscopic combined intrarenal surgery. MATERIALS AND METHODS Thirty consecutive patients who underwent endoscopic combined intrarenal surgery for renal calculi, between April 2014 and July 2015, were divided into the RVS-guided puncture (RVS; n = 15) group and the ultrasonography-guided puncture (US; n = 15) group. In the RVS group, renal puncture was repeated until precise piercing of a papilla was achieved under direct endoscopic vision, using the RVS system to synchronize the real-time US image with the preoperative computed tomography image. In the US group, renal puncture was performed under US guidance only. In both groups, 2 urologists worked simultaneously to fragment the renal calculi after inserting the miniature percutaneous tract. The mean sizes of the renal calculi in the RVS and the US group were 33.5 and 30.5 mm, respectively. RESULTS A lower mean number of puncture attempts until renal access through the calyx was needed for the RVS compared with the US group (1.6 vs 3.4 times, respectively; P=.001). The RVS group had a lower mean postoperative hemoglobin decrease (0.93 vs 1.39 g/dL, respectively; P=.04), but with no between-group differences with regard to operative time, tubeless rate, and stone-free rate. None of the patients in the RVS group experienced postoperative complications of a Clavien score >= 2, with 3 patients experiencing such complications in the US group. CONCLUSION RVS-guided renal puncture was effective, with a lower incidence of bleeding-related complications compared with US-guided puncture. (C) 2017 Elsevier Inc.