Presentation Authors: Alexey Martov*, Andrey Andronov, Sergey Dutov, Moscow, Russian Federation, Olivier Traxer, Paris, France
Introduction: Conventional PCNL has been commonly used for large kidney stones for a long time. New possibilities of minimally invasive operative techniques emerged with technological improvement of the instruments. Micro-PCNL has acquired popularity in recent years due to its high efficiency and low complications rate. Kidney stones less than 1.5 cm, low calyceal stones, and stones in calyceal diverticulum are the main indications for micro-PCNL. Considering the small size of the â€œall-seeing-needleâ€, stone disintegration can be achieved mostly by means of laser energy. Holmium laser is typically used for this procedure. New Thulium SuperPulse Fiber Laser (TSPFL) with wavelength 1940 nm has been developed, cleared, and introduced into the clinical practice in 2016 (IRE-Polus, RF). The aim of the study is to evaluate stone free-rate and safety of Micro-PCNL with TSPFL.
Methods: Since June 2018 till October 2018, Micro-PCNL has been performed in 14 patients (8 females, 6 males, age range 30 to 71) with single kidney stones. All patients underwent preoperative ultrasound and CT-scan with stone density evaluation. Location of stones was as follows: renal pelvis â€“ 6 cases, low calyx â€“ 6 cases and middle calyx â€“ 2 cases. Stone size varied between 7 and 19 mm. Stone density varied from 560 to 1380 HU. All operations started with kidney catheterization and ureteral sheath 10-12F placement for passive fragment evacuation during the procedure. We performed Micro-PCNL with special PolyDiagnost micro-optics with resolution 10000 pixels passed through the working sheath of the puncture needle 4.85F. Stones were fragmented and dusted with TSPFL (FiberLase U2, IRE-Polyus, RF) with the use of the 200 Î¼m laser fiber. The laser mode for fragmentation was 1-1.5 J and 15-30 Hz and for dusting 0.1-0.3 J and 50-100 Hz. Control exam with kidney CT-scan was performed 30 days after surgery.
Results: The following criteria for stone-free status were adopted: 1) no residuals exceeding 3 mm and 2) no need for auxiliary procedures. Stone free-rate was in 92.8% (13 cases) 30 days after surgery. Operation time was variable and ranged between 55 and 105 min. Stone fragmentation time (or lasering time) was 8Â±6 min. Complication rate was low and included postoperative infection in one patient with significant bacteriuria and haematuria in one patient with coagulopathy. No serious bleeding or tissue perforation was observed during operation. The double-J stent was placed in one patient with renal colic because of â€œsteinstrasseâ€ developing after the surgery. This patient underwent ESWL afterwards. Postoperative stay was 3.4Â±1.2 days.
Conclusions: Micro-PCNL conducted with the new TSPFL is effective and safe for the endourological management of renal stone disease.