Effect of pulse energy, frequency and length on holmium

• Verfasst von: Wezel, Felix [VerfasserIn]
• Verfasst von: Häcker, Axel [VerfasserIn]
• Verfasst von: Gross, Andreas [VerfasserIn]
• Verfasst von: Michel, Maurice Stephan [VerfasserIn]
• Verfasst von: Bach, Thorsten [VerfasserIn]
• Titel: Effect of pulse energy, frequency and length on holmium
• Titelzusatz: yttrium-aluminum-garnet laser fragmentation efficiency in non-floating artificial urinary calculi
• Verf.angabe: Felix Wezel, M.D., Axel Häcker, M.D., Andreas J. Gross, M.D., Maurice Stephan Michel, M.D., and Thorsten Bach, M.D.
• E-Jahr: 2010
• Jahr: 12 Jul 2010
• Umfang: 6 S.
• Fussnoten: Gesehen am 11.12.2023
• Titel Quelle: Enthalten in: Journal of endourology
• Ort Quelle: Larchmont, NY : Liebert, 1999
• Jahr Quelle: 2010
• Band/Heft Quelle: 24(2010), 7, Seite 1135-1140
• ISSN Quelle: 1557-900X
• DOI: doi:10.1089/end.2010.0115
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1873059361

Abstract

Background and Purpose: Holmium:yttrium-aluminum-garnet (Ho:YAG) laser lithotripsy is the standard lithotrite in ureteroscopy. We investigated the influence of pulse frequency, energy and length on the fragmentation efficiency of Ho:YAG laser lithotripsy in non-floating artificial stones in vitro. - - Materials and Methods: Stone fragmentation efficiency of three different Ho:YAG laser devices were evaluated in vitro at different pulse energy (1.0 and 2.0 J) and frequency settings (5 and 10 Hz), resulting in a standardized output power of 10W, respectively. Where possible, pulse length was modified (350 vs 700 μsec). Each setting was performed with a 273 μm and a 365 μm fiber. Lithotripsy was conducted using non-repulsive stones consisting of soft stone (plaster of Paris) and hard stone composition (Fujirock type 4). - - Results: Our results showed an increased stone disintegration efficiency at higher pulse energy (2.0 J/5 Hz vs 1.0 J/10 Hz) independently of two fiber diameters and stone types applied in this study (P < 0.05 in 18 of 20 groups). Similarly, reduction of the pulse length from 700 to 350 μsec resulted in a higher stone disintegration (P < 0.05 in 13 of 16 groups). This effect was most prominent when applied to soft stones. Higher fiber diameter was not constantly associated with an increase in stone disintegration. - - Conclusion: We demonstrate that an increase of pulse energy and a reduction of pulse length at a standardized output power of 10W can improve Ho:YAG laser fragmentation efficiency in vitro in nonfloating stones. These results may potentially affect clinical practice of Ho:YAG laser lithotripsy in impacted or large stones, when retropulsion is excluded.