Design
upper tract carcinoma, kidney stones
BENIGN PROSTATIC HYPERPLASIA, STRICTURE, SECONDARY, KIDNEY STONE, URETERAL STONE
Once informed consent was obtained, patients with kidney stones from 10 to 20 mm were randomly assigned to undergo RIRS using a SP TFL (NTO IRE-Polus, Russia) laser with a reusable LF diameter of 150 μm or 200 μm or a Ho:YAG laser (Lumenis, USA) with a 200-μm reusable LF at a 1:1:1 ratio. Exclusion criteria were multiple (more than three) kidney stones over 5 mm in diameter; ureteral stones; anticoagulant or antiplatelet therapy, the need for secondary simultaneous surgical intervention (for benign prostatic hyperplasia, upper tract carcinoma, urethral and ureteral stricture), and history of previous stone surgery or SWL.Based on a non-inferiority sample size calculation, in total 87 patients (29 per group) should have been included in the study for an 80% statistical power with the upper limit of a one-sided 95% confidence interval exceeding a > 5% difference in favor of the standard treatment group. Bearing in mind a drop-off rate of 20%, 105 participants were included (35 patients in each group). For the randomization of the patients, a computer‐generated allocation sequence was used. Patients were assigned treatment on a masked basis. An online system for randomization was used (The primary objective of the study was to evaluate the efficiency of lithotripsy using fibers with different diameters, measured through the following parameters: laser on time (LOT), ablation speed (mm