Comparative Evaluation of Temperature Generation during Laser Lithotripsy: Thulium Fiber Laser, Pulsed Thulium:YAG, and Holmium:YAG with Pulse Modulation "Presentation" - Bruce Gao
April 27, 2025
Bruce Gao, MD, FRCSC, Urologist, Department of Urology, University of California, Irvine, Irvine, CA
Bruce M. Gao: Dear UroToday viewers, we present the first ex vivo temperature evaluation of the thulium fiber laser by Soltive, pulsed thulium:YAG laser, Thulio®, and pulse-modulated holmium-- YAG laser, or MOSES. 18 porcine kidney-ureter units were implanted with Bego stones. They underwent 10 minutes of continuous lasering through a 200-micrometer laser fiber at 0.3 joules and 50 to 60 Hertz.
Temperature monitoring was conducted via percutaneously placed thermocouple in the renal pelvis. Saline irrigation was run at 150 milligrams of mercury using room temperature saline. The TFL showed the highest temperature increase from room temperature of 8.13 degrees Celsius. The thulium:YAG had a moderate increase of 4.1 degrees, and the holmium:YAG had the lowest increase of 3.3 degrees.
It is important to note that all temperature rises remained within a safe thermal range of less than 43 degrees Celsius. In conclusion, TFL generates significantly more heat than pulsed thulium:YAG and pulse-modulated holmium:YAG, yet all three remain within a safe thermal range during prolonged continuous testing. Thank you.