The Impact of Through-and-through Guidewire on Percutaneous Nephrolithotomy

The aim to the study is to investigate the impact of combined retrograde and antegrade insertion of a through-and-through guidewire during percutaneous nephrolithotomy (PCNL). Adult patients with complex renal stones (Guy's stone score III, IV) were ranomized between standard PCNL (control group) and PCNL with comibined retrograde and antegrade inserted through-and-through guidewire (study group). This modification initially involves the retrograde insertion of an additional guidewire beside the ureteral catheter. After percutaneous puncture and dilation of the tract, the guidewire is pulled antegrade through the renal access, using either ureteroscopy or nephroscopy to secure the tract throughout the procedure.The primary outcome is to compare the initial stone free rate (SFR) between both groups. The secondary outcome is to compare both groups as regard operative time, fluorscopy time, number of tracts, haemoglobin drop, blood transfusion and major complications accoridng to Clavien-Dindo (CD) system. Success is defined as presence of insignificant residual less than 4 mm.