V11-11 Thulium Lithotripsy: From Experiment to Clinical Practice

You have accessJournal of UrologyUrolithiasis1 Apr 2017V11-11 THULIUM LITHOTRIPSY: FROM EXPERIMENT TO CLINICAL PRACTICE Alim Dymov, Petr Glybochko, Yuri Alyaev, Andrey Vinarov, Gregory Altshuler, Viktoria Zamyatina, Nikolay Sorokin, Dmitri Enikeev, Vladimir Lekarev, Alexandra Proskura, and Alexey Koshkarev Alim DymovAlim Dymov , Petr GlybochkoPetr Glybochko , Yuri AlyaevYuri Alyaev , Andrey VinarovAndrey Vinarov , Gregory AltshulerGregory Altshuler , Viktoria ZamyatinaViktoria Zamyatina , Nikolay SorokinNikolay Sorokin , Dmitri EnikeevDmitri Enikeev , Vladimir LekarevVladimir Lekarev , Alexandra ProskuraAlexandra Proskura , and Alexey KoshkarevAlexey Koshkarev View All Author Informationhttps://doi.org/10.1016/j.juro.2017.02.3000AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES To date Holmium (Ho) laser is one of the most popular and effective tools for lithotripsy. It emits very short pulses (0.1 – 1 ms) with high peak power (0.5-10 kW) that allows to efficiently fragment any type of urinary stones. Series of articles show Ho laser wavelength of 2.1 μm is significantly off the peak of water absorption, and so can negatively affect efficiency of stone fragmentation. They also stressed that the thulium (Tm) fiber laser with diode laser pumping can improve stone fragmentation, because emission of Tm laser with wavelength 1.94 μm is 4.5 times stronger absorbed by water than that of Ho laser. There is a lot of data on feasibility and efficacy of Tm laser application for stone fragmentation in vitro. Nevertheless, Thulium laser lithotripsy hasn't been widely utilized in the clinical settings. A prototype Tm fiber laser with a peak power up to 500 W were developed by NTO «IRE – Polus» METHODS We have evaluated in vitro performance of a prototype Tm fiber laser with a peak power up to 500 W as a potentially alternative for modern Ho laser system. The in vitro experimental setup for measuring the stone fragmentation rate (ablation rate) included a specially designed cuvette with several levels of meshes allowing for precise quantification of size distribution of stone fragments (for the modes of fragmentation and dusting). Post – surgery human stones and BegoStone phantoms were used. The laser parameters (pulse energy and average power) were identical. Also retropulsion effect caused by a single pulse has been evaluated. Lateral shift of a stone after a single pulse of laser energy was measured. RESULTS ¥ Proposed experimental technique offers relatively simple and reliable method of comparing performance of laser lithotripters under controlled ex vivo conditions ¥ The Tm system, at identical laser parameters, produced about 2.3 and 1.3 times greater average ablation rate than the Ho system does in dusting and fragmentation modes, respectively ¥ The ratio of ablation rates on BegoStone phantoms correlated well with human stone data and varied between 1.6 and 2.3 ¥ The effect of retropulsion of the Tm laser (at 500 W) was 75%, 60%, and 29% of that of the Ho laser for equal pulse energies of 1, 2, and 3 J, respectively. The retropulsion onset threshold was significantly higher for Tm laser CONCLUSIONS Supported by this experimental data we assessed the clinical effectiveness of Tm fiber Urolase system with peak power of 120 W for lithotripsy. Several bladder stones with the average size about 1.9 cm were successfully destroyed. Further investigation in to the clinical applicability of Thulium lithotripsy is required. © 2017FiguresReferencesRelatedDetails Volume 197Issue 4SApril 2017Page: e1285 Advertisement Copyright & Permissions© 2017MetricsAuthor Information Alim Dymov More articles by this author Petr Glybochko More articles by this author Yuri Alyaev More articles by this author Andrey Vinarov More articles by this author Gregory Altshuler More articles by this author Viktoria Zamyatina More articles by this author Nikolay Sorokin More articles by this author Dmitri Enikeev More articles by this author Vladimir Lekarev More articles by this author Alexandra Proskura More articles by this author Alexey Koshkarev More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...