Introduction: The in vitro effects of thulium fiber laser (TFL) for lithotripsy has been previously described.1 We aim to describe the first North American clinical experience in the use of thulium laser lithotripsy in mini-PCNL.
Methods: A consecutive series of patients undergoing mini-PCNL with the TFL (SoltiveTM, Olympus Surgical) at two institutions was reviewed. Mini-PCNL with 16.5F dilation/17.5 sheath was performed with Storz MIPS system. The TFL was utilized in all cases for lithotripsy. Dust, stone debris, and fragments were cleared in standard fashion through nephrostomy sheath. Visual and fluoroscopic stone clearance was confirmed for all patients. Operative technique and postoperative management were maintained at the institutional standard.
Results: Six patients underwent mini-PCNL with TFL. Five cases were unilateral and performed supine and one patient had a bilateral mini-PCNL in the prone position. Mean age was 51, mean BMI was 30. Mean Charlson Comorbidity Index was 1.3 and mean ASA score was 2.8. 3 of 7 renal units had a single primary stone vs. 4 of 7 with more than one significant stone. Mean stone volume in primary calculus was 4,940mm3. Laser energy settings ranged from 0.1-1.0J and rate ranged from 20-500Hz. Mean laser time was 18.1 minutes (range = 0.9-28 min). Mean laser energy was 15.9kJ (range 1.6-64kJ). There were no intraoperative complications. 3 patients received stents, for a mean of 8 days. 2 of the 7 renal units had nephrostomy placed at end of case, both removed the next day. One patient had an extended 4 day hospital stay for treatment of bacteremia. Overall mean hospital stay was 1.6 days (range 1-4 days). Mean decrease in creatinine and hemoglobin were 0.1mg/dL and 1.0g/dL respectively. No blood transfusions were performed.
Conclusions: In this initial North American cohort, the TFL has been shown to be promising as a safe and effective modality for clearance of calculi during mini-PCNL. Our group has noted synergy in the ability to clear stone when TFL is used in combination with supine mini-PCNL, in both fragmentation and dusting modes. Larger cohort and longer follow up is needed for further evaluation of this new technology.
1. Knudsen* B, Chew B, Molina W. MP79-1: SUPER PULSE THULIUM FIBER LASER COMPARED TO 120W HOLMIUM:YAG LASER: IMPACT ON RETROPULSION AND LASER FIBER BURN BACK. Journal of Urology. 2019. Source of
Funding: SoltiveTM Thulium Fiber Laser was provided to institutions on a trial basis
