Objective: To evaluate the safety and feasibility of percutaneous tract dilation by the one-stage method in preschool children. Methods: Between April 2009 and February 2013, all preschool (<6 years) children who were candidates for percutaneous nephrolithotomy were enrolled in this prospective study. Patients were randomly assigned to dilation by serial metallic dilators (group!, 31 patients) or dilation by one-stage Amplatz according to Frattini et al. [J Endourol 2001;15:919-923] (group II, 31 patients). The primary end-point of interest was fluoroscopy time. Secondary endpoints included tract creation and dilation time, success rate and complications. Stone-free status was defined as residuals mm. Results: Age, stone size, operation success and operation time were not significantly different between the studied groups. The most common stone composition was calcium oxalate in both groups. The mean standard deviation of access and fluoroscopy times in groups I and II were 7.3 +/- 1.2 min vs. 5.9 +/- 1.5 min (p > 0.05) and 70.0 +/- 8.9 s vs. 22.0 +/- 5.6 s (p < 0.001), respectively. Postoperative complications included one case of postoperative fever lasting less than 48 h in group I. Conclusions: Percutaneous tract dilation by the one-stage method is safe and effective. Also, it is associated with considerably less radiation exposure in preschool children. (c) 2014 S. Karger AG, Basel
