PMID- 31339599 OWN - NLM STAT- MEDLINE DCOM- 20201113 LR - 20201113 IS - 1550-9613 (Electronic) IS - 0278-4297 (Linking) VI - 39 IP - 2 DP - 2020 Feb TI - Comparative Study of Pulsed Versus Continuous High-Intensity Focused Ultrasound Ablation Using In Vitro and In Vivo Models. PG - 259-271 LID - 10.1002/jum.15098 [doi] AB - OBJECTIVES: To compare the efficacy of pulsed high-intensity focused ultrasound (PHIFU) versus continuous high-intensity focused ultrasound (CHIFU) ablation at identical doses. METHODS: Continuous and pulsed HIFU (1200 J) at duty cycles (DCs) of 60% and 20% were examined for their capacity to ablate bovine liver tissue in vitro and rabbit liver tissue in vivo. After ablation, grayscale changes and pathologic characteristics were observed or measured, and the tissue necrosis volume, energy efficiency factor, and average grayscale density were calculated. RESULTS: The pulsed mode generated greater liquefaction necrosis. An inconspicuous grayscale change was observed for PHIFU at a DC of 20% in some samples, which appeared as an elliptical cavity. The energy efficiency factor of PHIFU at a DC of 60% was significantly lower than that of CHIFU, as observed both in vitro and in vivo (P < .05). The grayscale value and average grayscale density in response to CHIFU were significantly greater than those in response to PHIFU (60% or 20%; P < .05). Histopathologic analysis revealed liquefaction necrosis in all PHIFU groups. CONCLUSIONS: At identical doses, compared with CHIFU, a single session of PHIFU can generate liquefaction necrosis and at a higher DC can improve ablation efficiency. This increased efficacy of PHIFU may involve enhancement of tissue destruction by cavitation effects and a reduction in the obstruction effect of endogenous microbubbles through cavitation effects or a more effective diffusion of heat. CI - (c) 2019 by the American Institute of Ultrasound in Medicine. FAU - Wang, Yanhao AU - Wang Y AD - State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Collaborative Innovation Center for Minimally Invasive and Noninvasive Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, 400016, China. AD - College of Stomatology, Chongqing Medical University, Chongqing, 401147, China. FAU - Wang, Qi AU - Wang Q AD - State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Collaborative Innovation Center for Minimally Invasive and Noninvasive Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, 400016, China. FAU - Luo, Yong AU - Luo Y AD - State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Collaborative Innovation Center for Minimally Invasive and Noninvasive Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, 400016, China. FAU - Jiang, Lu AU - Jiang L AD - State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Collaborative Innovation Center for Minimally Invasive and Noninvasive Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, 400016, China. FAU - Zeng, Zihuan AU - Zeng Z AD - State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Collaborative Innovation Center for Minimally Invasive and Noninvasive Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, 400016, China. FAU - Gan, Lidan AU - Gan L AD - State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Collaborative Innovation Center for Minimally Invasive and Noninvasive Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, 400016, China. FAU - Chen, Jianli AU - Chen J AD - State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Collaborative Innovation Center for Minimally Invasive and Noninvasive Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, 400016, China. FAU - Han, Hongfei AU - Han H AD - State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Collaborative Innovation Center for Minimally Invasive and Noninvasive Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, 400016, China. FAU - Zou, Jianzhong AU - Zou J AUID- ORCID: 0000-0003-2500-0317 AD - State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Collaborative Innovation Center for Minimally Invasive and Noninvasive Medicine, College of Biomedical Engineering, Chongqing Medical University, Chongqing, 400016, China. LA - eng GR - cstc2015jcyjA50001/Chongqing Research Program of Basic Research and Frontier Technology/ GR - 11574039/National Natural Science Fund of the Chinese National Science Foundation/ GR - 2013YQ030629/the National Instrumentation Program/ PT - Comparative Study PT - Journal Article DEP - 20190724 PL - England TA - J Ultrasound Med JT - Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine JID - 8211547 SB - IM MH - Animals MH - Cattle MH - High-Intensity Focused Ultrasound Ablation/*methods MH - Liver/*surgery MH - Models, Animal MH - Rabbits OTO - NOTNLM OT - ablation OT - comparison OT - duty cycle OT - high-intensity focused ultrasound OT - identical doses EDAT- 2019/07/25 06:00 MHDA- 2020/11/18 06:00 CRDT- 2019/07/25 06:00 PHST- 2019/02/15 00:00 [received] PHST- 2019/06/26 00:00 [revised] PHST- 2019/07/01 00:00 [accepted] PHST- 2019/07/25 06:00 [pubmed] PHST- 2020/11/18 06:00 [medline] PHST- 2019/07/25 06:00 [entrez] AID - 10.1002/jum.15098 [doi] PST - ppublish SO - J Ultrasound Med. 2020 Feb;39(2):259-271. doi: 10.1002/jum.15098. Epub 2019 Jul 24.