MP24-10 WAVELENGTH AND PULSE SHAPE EFFECTS ON STONE FRAGMENTATION OF LASER LITHOTRIPTERS

Abstract

You have accessJournal of UrologyStone Disease: Basic Research & Pathophysiology II1 Apr 2018MP24-10 WAVELENGTH AND PULSE SHAPE EFFECTS ON STONE FRAGMENTATION OF LASER LITHOTRIPTERS Andreas Gross, Benedikt Becker, Mark Taratkin, Dmitry Enikeev, Leonid Rapoport, and Christopher Netsch Andreas GrossAndreas Gross More articles by this author , Benedikt BeckerBenedikt Becker More articles by this author , Mark TaratkinMark Taratkin More articles by this author , Dmitry EnikeevDmitry Enikeev More articles by this author , Leonid RapoportLeonid Rapoport More articles by this author , and Christopher NetschChristopher Netsch More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2018.02.763AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Pulsed Holmium:YAG lasers are the energy source of choice in the endoscopic management of urolithiasis. Until recently, pulse frequency and pulse energy were the most investigated parameters to improve efficiency of such lasers. Newer research focusses on the influence of pulse width and pulse shape. Aim of our study was to compare the efficiency of stone dusting of pulsed 2.1µm Holmium:YAG lasers and a pulsed 1.94µm Thulium-fiber laser (TFL) using identical pulse energy, pulse frequency, and average power settings. METHODS The lasers systems tested were the Lumenis Versa Pulse Power Suite P 100 (Ho short pulse), the Lumenis Pulse 120H (Ho long pulse) and a commercially not available prototype of a pulsed TFL (Fig.1, A) to C)). The lasers were tested at 0.2 J and 40 Hz (average power of 8-W). Pulse energies and pulse shapes were measured. Subsequently, efficiency of stone ablation (ablation speed) was compared in vitro on human COM, COM-phosphate, and Uric Acid stones for the three lasers. The in vitro experimental setup included a specially designed cuvette with several levels of metallic meshes allowing for precise quantification of size distribution of stone fragments. RESULTS The pulsewidths (range in ms) of all three lasers are shown in Fig. 1 below. The following values of the peak power were derived from the pulse shape and pulse energy measurements: P100: 1650-W, P120: 1040-W, TFL: 660-W. The measured values of stone ablation speed (in dusting mode, i.e. fragments < 1mm) are summarized in Fig.2. CONCLUSIONS The new pulsed TFL shows a clearly defined pulsewidth with a large area under the curve. This in combination with the wavelength superior in terms of water absorption leads to better efficiency of stone fragmentation in dusting mode. © 2018FiguresReferencesRelatedDetails Volume 199Issue 4SApril 2018Page: e293-e294 Advertisement Copyright & Permissions© 2018MetricsAuthor Information Andreas Gross More articles by this author Benedikt Becker More articles by this author Mark Taratkin More articles by this author Dmitry Enikeev More articles by this author Leonid Rapoport More articles by this author Christopher Netsch More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...