MP04-02 ANALYSIS OF EX-VIVO HUMAN BPH TISSUE TREATED BY HISTOTRIPSY: DOSE AND PARAMETER EFFECTS

Abstract

You have accessJournal of UrologyCME1 May 2022MP04-02 ANALYSIS OF EX-VIVO HUMAN BPH TISSUE TREATED BY HISTOTRIPSY: DOSE AND PARAMETER EFFECTS Zorawar Singh, Yashwanth N. Kumar, Yak-Nam Wang, Adam Maxwell, Matthew Bruce, Rishi Sekar, Eli Vlaisavljevich, Lawrence D. True, and George R. Schade Zorawar SinghZorawar Singh More articles by this author , Yashwanth N. KumarYashwanth N. Kumar More articles by this author , Yak-Nam WangYak-Nam Wang More articles by this author , Adam MaxwellAdam Maxwell More articles by this author , Matthew BruceMatthew Bruce More articles by this author , Rishi SekarRishi Sekar More articles by this author , Eli VlaisavljevichEli Vlaisavljevich More articles by this author , Lawrence D. TrueLawrence D. True More articles by this author , and George R. SchadeGeorge R. Schade More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002521.02AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Histotripsy is a promising alternative to more invasive procedures for the treatment of benign prostatic hyperplasia (BPH). However, in a phase 1 clinical trial, histotripsy failed to provide objective improvements in urinary function. One explanation may be that the clinical trial pulse parameters, optimized in a canine model, do not translate to more fibrotic human prostates. We aimed to evaluate the efficacy of different histotripsy parameter settings to identify a more efficacious exposure in ex-vivo human BPH tissue (EVHP). METHODS: Deidentified EVHP tissue specimens (n=17) were treated with an 18 element 700kHz cavitation histotripsy transducer, which approximated the device used in the prior clinical trial, and a 1.5MHz boiling histotripsy (BH) transducer. Three different histotripsy exposures were compared: 1) a high pulse repetition frequency (PRF) (approximating the clinical system cavitation cloud histotripsy [CCH]), 2) low PRF CCH and 3) 1Hz PRF BH. Treatment effectiveness was evaluated by measuring pre vs. post treatment Young’s modulus through shear wave elastography (SWE) and histologic analysis (H&E, Masson’s Trichome) of the targeted area. The dose was standardized at 30s/mm and escalated as required to note a significant change in SWE. RESULTS: At the given dose of 30s/mm, BH treatments resulted in a significant 40.1% reduction in SWE Young’s modulus (Figure 1A) p < 0.001. At this dose, neither of the CCH parameter settings (500Hz and 10Hz) resulted in a significant reduction in the Young’s modulus with % changes of differences of 3.1% (p = .83) and -5% (p = .08), respectively. For CCH settings, greater exposure times (up to 90s) did result in significant stiffness reduction of 12.5% (p = 0.04) and 41.1% (p < 0.001) for 500Hz and 10Hz parameter settings, respectively. On histology (Figure 1B), at 30s/mm, the CCH parameter settings resulted in minimal intermittent damage while BH treatments caused near complete ablation. At increasing doses, CCH was also capable of causing complete liquefactive cavity formation. CONCLUSIONS: BH parameters applied in this study resulted in more complete ablation of EVH tissue in comparison to CCH parameters. Additionally, histotripsy treatment parameters similar to those applied with a previous clinical system did not produce consistent ablation of EVHP possibly explaining trial results. Source of Funding: None © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 207Issue Supplement 5May 2022Page: e56 Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.MetricsAuthor Information Zorawar Singh More articles by this author Yashwanth N. Kumar More articles by this author Yak-Nam Wang More articles by this author Adam Maxwell More articles by this author Matthew Bruce More articles by this author Rishi Sekar More articles by this author Eli Vlaisavljevich More articles by this author Lawrence D. True More articles by this author George R. Schade More articles by this author Expand All Advertisement PDF DownloadLoading ...