Efficacy and safety of 6.3-Fr versus 8.6-Fr disposable digital flexible ureteroscopes for pediatric upper urinary tract stones ≤ 2 cm: a randomized controlled trial
摘要
To compare the efficacy and safety of 6.3-Fr versus 8.6-Fr disposable digital flexible ureteroscopes for pediatric upper urinary tract stones ≤ 2 cm.
MethodsA single-surgeon, prospective, randomized controlled trial was conducted at our center between September 2024 and September 2025. Children undergoing surgery for upper urinary tract stones were randomized (1:1) to the 6.3-Fr or 8.6-Fr group. Inclusion criteria included: (1) age < 18 years; (2) upper urinary tract stones ≤ 2 cm confirmed by Computed Tomography (CT); and (3) informed consent obtained. Exclusion criteria were: (1) congenital anomalies of the kidney and urinary tract (CAKUT); (2) severe renal insufficiency; (3) major cardiopulmonary dysfunction or coagulopathy; and (4) ipsilateral ureteroscopic procedures or double-J (DJ) stent placement within the previous 3 months. Preoperative characteristics, operative time, stone-free rate (SFR) at 4 weeks, perioperative complications, number of anesthesia events, and hospitalization-related parameters were collected. The study was registered at ClinicalTrials.gov (NCT06628765).
ResultsForty children were included, with 20 patients in each group. Baseline demographics and stone characteristics were comparable. The first-attempt ureteroscope insertion success rate was higher in the 6.3-Fr group than in the 8.6-Fr group (60.0% vs. 20.0%, p = 0.010). During second-stage procedures, sheathless retrograde intrarenal surgery (RIRS) was more frequently performed in the 6.3-Fr group (62.5% vs. 12.5%, p = 0.021). Median hospitalization costs were significantly lower in the 6.3-Fr group (13,510 vs. 17,643 CNY, p = 0.001). The number of anesthesia events and the rate of postoperative stent placement also differed significantly between groups (p < 0.05). Both operative time, length of hospital stay, SFR at 4 weeks, and postoperative complications did not differ significantly (p > 0.05).
ConclusionThis study provides the first evidence supporting the efficacy and safety of the 6.3-Fr disposable flexible ureteroscope in children. The smaller-diameter device was associated with higher first-pass insertion success, fewer anesthesia events, and reduced hospitalization costs, offering clear advantages in pediatric RIRS.