Study of Temperature Changes around Fibres in Super Pulse Thulium Fibre Laser in Vitro Lithotripsy

To investigate temperature changes around the fibres of the super pulse thulium fibre laser (SP-TFL) during in vitro lithotripsy. Stones were placed in the in vitro model. The laser was continuously excited for 180 s; the probe was positioned 5 mm around the fibre; the laser power was set at 10, 15, 20, 25, and 30 W; and the irrigation rate was set at 0, 15, 25, 35 ml/min, using a domestic SP-TFL. The temperature variations around the fibre under different power settings and different irrigation rates were compared. Without irrigation, the temperature around the fibre rapidly reached the safety threshold of 43℃ at 24 s. At irrigation rate 15 ml/min and laser power