Treatment of Urolithiasis with Thulium Fiber Laser in Fragmentation Mode Using Optimized Pulse Sequences

Area of Science:

• Urology
• Laser technology
• Nephrolithiasis treatment

Background:

• Super-pulsed thulium fiber laser (SP TFL) is an emerging alternative for intracorporeal lithotripsy.
• While SP TFL shows promise in dusting, its fragmentation efficiency requires further investigation.
• The second-generation SP TFL incorporates an advanced fragmentation pulse (AFP) sequence to enhance fragmentation capabilities.

Purpose of the Study:

• To evaluate the safety and efficacy of the second-generation SP TFL in fragmentation mode.
• To assess SP TFL's performance in ureteroscopy (URS) and mini percutaneous nephrolithotomy (mini-PCNL).

Main Methods:

• Ex vivo safety assessment comparing AFP to standard SP TFL fragmentation on porcine kidney tissue using histological analysis.
• Clinical evaluation involving 40 patients undergoing URS or mini-PCNL for ureteral and renal stones.
• Recording stone characteristics (size, volume, density) and laser parameters (laser-on-time, total energy, AFP energy, average power).

Main Results:

• Ex vivo analysis showed similar mucosal damage profiles between AFP and regular SP TFL pulses.
• Clinical phase demonstrated effective fragmentation of diverse ureteral and renal stones for extraction.
• Median stone volumes were 0.4 cm³ (ureteral) and 1.3 cm³ (renal); median densities were 1029 HU and 1113 HU, respectively.
• Low overall complication rates were observed in both URS and mini-PCNL groups.

Conclusions:

• The second-generation SP TFL with AFP capability provides effective fragmentation of ureteral and renal stones regardless of composition.
• This laser technology is safe and efficient for use in URS and mini-PCNL procedures.
• Minimal complication rates are associated with SP TFL fragmentation for lithotripsy.