Percutaneous nephrolithotomy for staghorn stones: a randomised trial comparing high-power holmium laser versus ultrasonic lithotripsy

Objective To compare high-power holmium laser lithotripsy (HP-HLL) and ultrasonic lithotripsy (US-L) for disintegration of staghorn stones during percutaneous nephrolithotomy (PCNL). Patients and Methods A non-inferiority randomised controlled trial was conducted between August 2011 and September 2014. Inclusion criteria were patients' aged >18 years who had complete staghorn stones (branching to the three major calyces), without contraindications to PCNL. Eligible patients were randomised between two groups: HP-HLL and US-. A standard PCNL in the prone position was performed for all patients. The only difference between the treatment groups was the method of stone disintegration. In the first group (HP-HLL), a laser power of 40-60 W (2 J, 20-30 Hz) was used to pulverise the staghorn stone into very small fragments, which could pass through the Amplatz sheath with the irrigation fluid. US-L, with suction of the fragments, was used in the second group. The primary outcome (stone-free rate) was evaluated with non-contrast computed tomography after 3 months. Secondary outcomes of complications, blood transfusion, operative time, and haemoglobin deficit were compared. The outcome assessor was 'blinded' to the treatment arm. Results The study included 70 patients (35 in each group). The baseline characteristics (age, sex, body mass index, side, stone volume, and density) and operative technique (number, size of tracts, and need for second PCNL session) were comparable for both groups. Operative time was significantly shorter in US-L group, at a mean (SD) of 130 (34) vs 148.7 (35) min (P = 0.028). The haemoglobin deficit was significantly more with in the US-L group, at a mean (SD) of 1.7 (0.9) vs 1.3 (0.6) g/dL (P = 0.037). The differences in blood transfusion (17% for US-L vs 11% for HP-HLL) and the complication rates (34% for US-L vs 23% for HP-HLL) were not significant (P = 0.495 and P = 0.290, respectively). The stone-free rates at 3 months were comparable (60% for US-L and 66% for HPL-L; P = 0.621). Conclusions Compared with US-L for intracorporeal lithotripsy of staghorn stones during PCNL, HP-HLL showed comparable safety and efficacy with a lower haemoglobin deficit but longer operative time.