title: Spatial-temporal ultrasound imaging of residual cavitation bubbles around a fluid-tissue interface in histotripsy.
abstract: Cavitation is considered as the primary mechanism of soft tissue fragmentation (histotripsy) by pulsed high-intensity focused ultrasound. The residual cavitation bubbles have a dual influence on the histotripsy pulses: these serve as nuclei for easy generation of new cavitation, and act as strong scatterers causing energy "shadowing." To monitor the residual cavitation bubbles in histotripsy, an ultrafast active cavitation imaging method with relatively high signal-to-noise ratio and good spatial-temporal resolution was proposed in this paper, which combined plane wave transmission, minimum variance beamforming, and coherence factor weighting. The spatial-temporal evolutions of residual cavitation bubbles around a fluid-tissue interface in histotripsy under pulse duration (PD) of 10-40 μs and pulse repetition frequency (PRF) of 0.67-2 kHz were monitored by this method. The integrated bubble area curves inside the tissue interface were acquired from the bubble image sequence, and the formation process of histotripsy damage was estimated. It was observed that the histotripsy efficiency decreased with both longer PDs and higher PRFs. A direct relationship with a coefficient of 1.0365 between histotripsy lesion area and inner residual bubble area was found. These results can assist in monitoring and optimization of the histotripsy treatment further.
authors.affiliation: The Key Laboratory of Biomedical Information Engineering of the Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China.
authors.forename: Hong
authors.initials: H
authors.lastname: Hu
authors.affiliation: The Key Laboratory of Biomedical Information Engineering of the Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Xu
authors.affiliation: The Key Laboratory of Biomedical Information Engineering of the Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Yuan
authors.affiliation: The Key Laboratory of Biomedical Information Engineering of the Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China.
authors.forename: Runna
authors.initials: R
authors.lastname: Liu
authors.affiliation: The Key Laboratory of Biomedical Information Engineering of the Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China.
authors.forename: Supin
authors.initials: S
authors.lastname: Wang
authors.affiliation: The Key Laboratory of Biomedical Information Engineering of the Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China.
authors.forename: Mingxi
authors.initials: M
authors.lastname: Wan
mesh_terms: D000465:Algorithms; D004867:Equipment Design; D005740:Gases; D057086:High-Intensity Focused Ultrasound Ablation / Q000295:instrumentation / Q000379:methods*; D008962:Models, Theoretical; D009038:Motion; D011312:Pressure; D012815:Signal Processing, Computer-Assisted; D013016:Sound; D013499:Surface Properties; D013997:Time Factors; D014160:Transducers, Pressure; D014465:Ultrasonics / Q000295:instrumentation / Q000379:methods*
chemical_list: D005740:Gases