Clinical Research Directory

Extracorporeal shock wave lithotripsy will be performed using a third-generation electromagnetic lithotripter The focal depth is 110 mm; the focal area is 7 mm (radial) and 45-50 mm (axial), and the focal pressure is 6-30 MPa). The procedure is performed in a supine or prone position without anesthesia. Stone localization and simultaneous real-time monitoring during the process will be performed by ultrasound). The shock frequency is 60-90 (shock waves/min). The total number of shock waves applied for one session is between 1500 and 2500 waves, or the session is stopped at a significant stone fragmentation is detected. The voltage applied per session ranged from 10 to 16 kV with stepwise power ramping strategy. All procedures in the SWL group are outpatient procedures.

All F-URS cases will be performed by a single surgeon (HMI). A guidewire is placed in the upper urinary tract through a rigid cystoscope under fluoroscopic guidance. An 8-10 F dual lumen catheter is used to dilate the intramural ureter and to fix a second guidewire with hydrophilic coat. The 7.5 F flexible ureteroscope is passed into the upper urinary tract in a monorail fashion over the second wire. A holmium-YAG laser is used at an energy setting of 0.8-1 J and a rate of 10-15 Hz. A 200 µm laser fibre is used for delivering laser energy to the stones. A 2.2 F tipless nitinol basket is used to displace the stones from the lower pole to an upper pole calyx before disintegration. Adequate fragmentation is considered when fragments are smaller than the diameter of the guide wire. Stone fragments will be left for spontaneous passage. At the end of the procedure, the whole collecting system will be inspected for residual stones and a double pigtail ureteric stent will be left for 2 weeks t