Treatment of upper urinary tract stones with flexible ureteroscopy in children.

This single-centre, retrospective study aimed to assess the efficacy and safety of flexible ureteroscopy (FURS) combined with holmium laser lithotripsy in treating children with upper urinary tract stones. From June 2014 to October 2015, a total of 100 children (74 boys and 26 girls) with upper urinary tract stones were treated using FURS. A 4.7 Fr double-J stent was placed two weeks before operation. Patients were considered stone-free when the absence of residual fragments was observed on imaging studies. The preoperative, operative, and postoperative data of the patients were retrospectively analyzed. A total of 100 pediatric patients with a mean age of 3.51±1.82 years underwent 131 FURS and holmium laser lithotripsy. Mean stone diameter was 1.49±0.92 cm. Average operation time was 30.8 minutes (range 15-60). The laser power was controlled between 18 and 32 W, and the energy maintained between 0.6 and 0.8 J at any time; laser frequency was controlled between 30 and 40 Hz. Complications were observed in 69 (69.0 %) patients and classified according to the Clavien system. Postoperative hematuria (Clavien I) occurred in 64 (64.0 %) patients. Postoperative urinary tract infection with fever (Clavien II) was observed in 8/113 (7.1%) patients. No ureteral perforation and mucosa avulsion occurred. The overall stone-free rate of single operation was 89/100 (89%). Stone diameter and staghorn calculi were significantly associated with stone-free rate. FURS and holmium laser lithotripsy is effective and safe in treating children with upper urinary tract stones.