In vitro fragmentation performance of a novel, pulsed Thulium solid-state laser compared to a Thulium fibre laser and standard Ho:YAG laser

Lasers Med Sci. 2022 Apr;37(3):2071-2078. doi: 10.1007/s10103-021-03495-8. Epub 2021 Dec 14.

Abstract

The aim of this work was to compare the fragmentation efficiency of a novel, pulsed Thulium solid-state laser (p-Tm:YAG) to that of a chopped Thulium fibre laser (TFL) and a pulsed Holmium solid-state laser (Ho:YAG). During the fragmentation process, we used a silicone mould to fixate the hemispherical stone models under water in a jar filled with room-temperature water. Each laser device registered the total energy applied to the stone model to determine fragmentation efficiency. Our study examined laser settings with single pulse energies ranging from 0.6 to 6 J and pulse frequencies ranging from 5 to 15 Hz. Similar laser settings were applied to explicitly compare the fragmentation efficiency of all three devices. We experimented with additional laser settings to see which of the three devices would perform best. The fragmentation performance of the three laser devices differed statistically significantly (p < 0.05). The average total energy required to fragment the stone model was 345.96 J for Ho:YAG, 372.43 J for p-Tm:YAG and 483.90 J for TFL. To fragment the stone models, both Ho:YAG and p-Tm:YAG needed similar total energy (p = 0.97). TFL's fragmentation efficiency is significantly lower than that of Ho:YAG and p-Tm:YAG. Furthermore, we found the novel p-Tm:YAG's fragmentation efficiency to closely resemble that of Ho:YAG. The fragmentation efficiency is thought to be influenced by the pulse duration. TFL's shortest possible pulse duration was considerably longer than that of Ho:YAG and p-Tm:YAG, resulting in Ho:YAG and p-Tm:YAG exhibiting better fragmenting efficiency.

Keywords: Holmium laser; Laser lithotripsy; Pulsed Thulium laser; Thulium fibre laser; Urinary stone; Urolithiasis.

MeSH terms

  • Calculi*
  • Holmium
  • Humans
  • Lasers, Solid-State* / therapeutic use
  • Lithotripsy, Laser* / methods
  • Thulium

Substances

  • Thulium
  • Holmium