Experimental study of the effects of laser sialolithotripsy

Abstract

BACKGROUND: The effectiveness of removing concretions using sialoendoscopy depends on the size and location of the concretion in the salivary gland. According to the research results, holmium YAG lasers are the predominant intracorporeal lithotriptors in crushing urolites and sialoliths. However, to date, in comparative studies of lasers of different types in urology, the Thule laser FiberLase U2 demonstrates high efficiency. Research by urologist surgeons served as the basis for the experiment on the possibility of crushing sialoliths and analyzing the physical effects. AIM: To evaluate the safety and time of crushing of sialolith using a thulium laser FiberLase U2 in vitro. MATERIALS AND METHODS: Twelve round-shaped sialolith with a diameter of 5–6 mm were selected for the study. A model simulating the gland duct was developed. The fiber of the FiberLase U2 laser was fed through the proximal end of the model, and a series of lithotripsies were performed sequentially in three modes of the device at maximum and minimum values of energy and pulse frequency, fixing the temperature rise during irrigation and the resulting effects during crushing. RESULTS: Crushing sialoliths to fragments measuring 1 mm is possible in all three laser modes. Operation at maximum values of pulse energy and frequency proceeded faster, whereas the maximum temperature rise varied from 45°C to 48°C, depending on the mode. Crushing was accompanied by pronounced cavitation and frequent sparks when the laser pulse was applied. Fragmentation at the minimum parameters of the pulse energy and frequency proceeded much slower; however, the maximum temperature rise ranged from 33°C to 40°C, and the listed effects were observed to a lesser extent in all three modes. CONCLUSION: The use of a Thule laser for crushing concretions in all three modes at maximum pulse energy and frequency is inefficient and unsafe. Work at minimum values of the dusting and popcorning modes has shown the best results; however, further study of crushing with this laser is necessary.