Ultrasound-Guided Shockwave Lithotripsy Reduces Radiation Exposure and Has Better Outcomes for Pediatric Cystine Stones

Background/Aims/Objectives: To evaluate the outcomes and ionizing radiation (IR) exposure of children with cystine stones (CS) using different shockwave lithotripsy (SWL) guidance modalities. Methods: Data from pediatric patients with renal stones treated between January 2009 and August 2015 were retrospectively reviewed. Outcome results and IR exposure in patients undergoing fluoroscopy (FL)-guided SWL and ultrasonography (US)-guided SWL were compared. First-time stone formers and those treated with SWL and with complete follow-up data, including post-treatment stone analysis confirming CS were included. Results: Forty-four patients (16 girls and 28 boys) met the inclusion criteria. Results of SWL performed in 51 kidneys were analyzed. After the SWL, 41 (80.4%) of 51 kidneys were stone free, and 10 (19.6%) had clinically insignificant residual fragments (≤3 mm) or unfragmented stones. The success rates differed between patients in Group-FL (60%) and Group-US (93.5%) (p = 0.008). Single-session success rates were higher, and prospects of retreatment were lower in Group-US (p = 0.000 and p = 0.002, respectively). In addition, overall complications were significantly lower in Group-US (p = 0.042). Overall IR exposure was higher in Group-FL (p = 0.013). Conclusions: US-guided SWL is more effective for pediatric CS and should be considered a preferred treatment to reduce IR doses in children.