First Clinical Experience of a Novel Pulsed Solid-State Thulium:YAG Laser during Percutaneous Nephrolithotomy

Abstract

Introduction: Laser lithotripsy during Mini-PCNL is one treatment option in urinary stone disease. In recent years, a new era in stone treatment has been initiated with the introduction of new pulsed thulium lasers. The aim of this study was to investigate the safety and efficacy of laser lithotripsy with a new pulsed solid-state thulium:YAG laser during mini-PCNL. Materials and methods: All patients, regardless of stone size, who were treated with a Mini-PCNL using the new pulsed thulium laser were prospectively enrolled. Operation times, stone size, laser time, and laser settings were noted. The stone-free rate was assessed postoperatively with sonography and either x-ray or computed tomography as a clinical standard. The complications were analyzed using the Clavien-Dindo classification. Results: A total of 50 patients with a mean age of 52 years were included. 31 (62 %) patients were male. The average stone size was 242.3 (±233.1) mm2 with an average density of 833 (±325) Hounsfield units. The mean operating time was 30.56 (±28.65) minutes, and the laser-on-time was 07:07 (± 07:08) minutes. The most commonly used settings were 0.4 J and 115 Hz (46 W). The mean total energy for stone ablation was 14,166 (±17,131) kJ. The total stone-free rate was 84 %, with an overall complication rate of 32% according to Clavien-Dindo (grade 1: n = 9, grade 2: n = 6, 3b: n = 1). In the group of patients with singular stones (n = 25), the stone-free rate was 88%. Summary: The new pulsed solid-state Thulium:YAG laser allows a safe and effective lithotripsy during Mini-PCNL. The stone-free rates were high regardless of stone size with a comparable low rate of complications.

Pulsed thulium:YAG laser—ready to dust all urinary stone composition types? Results from a PEARLS analysis

“…The findings of this study are pivotal for the broader future implementation of the p-Tm:YAG in clinical routine, considering that studies found in the literature so far have presented data based on non-human stone lithotripsy models (BegoStone, plaster of paris, gypsum/glass) [ 13 , 14 , 22 ], or if conducted in humans did not investigate laser effects on different human urinary stone compositions [ 16 ]. It is of particular interest to note that the p-Tm:YAG was amenable to lithotripsy of cystine stones, akin to the Ho:YAG and TFL [ 23 ].…”

“…It is important to note that these preliminary reports were based on lithotripsy models using artificial Bego Stones—and not human urinary stones—with the primary outcome being stone ablation efficiency rather than evaluation of stone dust per se. Two recent in vivo studies evaluated the clinical efficacy and safety of the p-Tm:YAG on case series of patients undergoing retrograde intrarenal surgery [ 15 ] and mini-percutaneous nephrolithotomy [ 16 ]. Both studies conclude that the p-Tm:YAG seems very promising, with patients included having a range of stone densities, although no information regarding exact differing stone compositions was provided.…”

Controversies in ureteroscopy: lasers, scopes, ureteral access sheaths, practice patterns and beyond

“…Recently, the pulsed Thulium:YAG laser has been proposed as a further alternative to the Ho:YAG, with promising stone dusting proprieties ( 23 ). Two clinical studies are available to date and reveal the pTm:YAG as an efficient and safe laser for lithotripsy ( 24 , 25 ).…”

Comparison of high and low pulse energy dusting protocols using holmium: YAG laser in flexible ureteroscopy for treatment of renal stones

“…The global prevalence of urinary stone disease treatment has shown a steady rise [ 1 ] Within the armamentarium of urinary stone management, the laser has emerged as a cornerstone for lithotripsy in endourological procedures [ 2 ]. The trajectory of laser technology has witnessed a progressive evolution, transitioning from the established holmium: yttrium-aluminum-garnet (Ho: YAG) laser with pulse modulation to the advent of thulium fiber laser (TFL) and, more recently, the innovative pulsed thulium: YAG (p-Tm: YAG) laser [ 3 ]…”