Mechanism of Lithotripsy by Superpulse Thulium Fiber Laser and Its Clinical Efficiency

Abstract

Thulium fiber laser with a wavelength of 1.94 µm is widely used in urology for lithotripsy. This paper studies the mechanism of lithotripsy and evaluates its clinical efficiency using the superpulse thulium fiber laser with a wavelength of 1.94 µm and a peak power of 500 W. An experimental setup was developed to study the mechanism of lithotripsy. The superpulse thulium fiber laser (TFL) with a wavelength of 1.94 µm with a peak power of 500 W (FiberLase U2 from “IRE-POLUS” Ltd., Fryazino, Moscow Region, Russia) was used for the lithotripsy of stone phantoms (BegoStone). The processes were recorded with a high-speed camera. The acoustic signals registered during lithotripsy were studied with wideband and needle hydrophones. The main mechanism of lithotripsy performed by using superpulse TFL was thermal cavitation in the water-filled pore space and thermal destruction of the phantom. During the clinical application of the superpulse thulium fiber laser, the high efficiency of laser lithotripsy was established. The performed optical and acoustic studies showed that the mechanism of the destruction of stones was based on the synergic effect of the explosive boiling of water in the pore space of the stone, and its thermal destruction is associated with the heating of the stone to several hundred degrees with laser radiation.

Moses and Moses 2.0 for Laser Lithotripsy: Expectations vs. Reality

“…Exclusion criteria included the use of MT in a non-endoscopic lithotripsy context and studies performed exclusively on pediatric patients. This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement [ 10 ].…”

“…In this way, the stone is heated and the chemical decomposition begins (photothermal mechanism). Simultaneously, the water contained within the pores of the stone surface also absorbs the laser energy and vaporizes, causing microexplosions and stone bursting from the inside (thermomechanical ablation) [ 8 , 9 , 10 ]. However, it was proposed that one half or more of the laser pulse is lost in the bubble formation [ 11 ].…”