Retrospective, multicenter evaluation of outcome in percutaneous nephrolitholapaxy using different energy sources for lithotripsy

Purpose: Mini percutaneous nephrolithotomy (mini-PNL) is an effective treatment for large renal stones, offering high stone clearance rates with low complication risks. This study aimed to compare the efficacy and safety of holmium YAG laser, ballistic, and ultrasound lithotripsy during mini-PNL. Methods: This multicenter prospective study analyzed 125 patients who underwent mini-PNL using either laser, ballistic, or ultrasound lithotripsy. Efficacy was assessed based on the stone-free rate (evaluated endoscopically and via fluoroscopy) and intrarenal surgery time adjusted for stone volume. Stone volume was estimated using automated CT-based computation when available or calculated using the ellipsoid volume formula. Complications were classified according to the Clavien-Dindo system. Results: A total of 125 patients (59 in Regensburg, 66 in Trier) were included. The primary energy sources were laser (54.4%) and EMS Trilogy (44%). In Regensburg, lithotripsy was performed using a laser in 96.6% of cases, whereas in Trier EMS Trilogy was used in 81.8% and laser in 16.7% of cases. The median intrarenal operative time was shorter with laser compared to EMS Trilogy (28.5 min vs. 35 min; p = 0.033). After adjustment for stone volume, the difference remained significant (mean difference = −18.77 min; p = 0.0001). There were no significant differences regarding stone-free rate (SFR) (laser 85.3% vs. EMS 72.8%; p = 0.222) or reintervention rate (laser 19.1% vs. EMS 23.6%; p = 0.8706). Postoperative complications occurred independently of the method used (Grade 1–2: laser 13.2% vs. EMS 29%; Grade 3–4: laser 5.9% vs. EMS 1.8%; p = 0.138). In the univariate analysis, higher BMI was associated with an increased rate of complications (p = 0.04). Conclusion: Compared with laser lithotripsy, the use of EMS Trilogy for stone fragmentation was associated with a significantly longer operative time, while complication rates and stone-free rates did not differ significantly.