title: Comparative study of lesions created by high-intensity focused ultrasound using sequential discrete and continuous scanning strategies.
abstract: Lesion formation and temperature distribution induced by high-intensity focused ultrasound (HIFU) were investigated both numerically and experimentally via two energy-delivering strategies, i.e., sequential discrete and continuous scanning modes. Simulations were presented based on the combination of Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation and bioheat equation. Measurements were performed on tissue-mimicking phantoms sonicated by a 1.12-MHz single-element focused transducer working at an acoustic power of 75 W. Both the simulated and experimental results show that, in the sequential discrete mode, obvious saw-tooth-like contours could be observed for the peak temperature distribution and the lesion boundaries, with the increasing interval space between two adjacent exposure points. In the continuous scanning mode, more uniform peak temperature distributions and lesion boundaries would be produced, and the peak temperature values would decrease significantly with the increasing scanning speed. In addition, compared to the sequential discrete mode, the continuous scanning mode could achieve higher treatment efficiency (lesion area generated per second) with a lower peak temperature. The present studies suggest that the peak temperature and tissue lesion resulting from the HIFU exposure could be controlled by adjusting the transducer scanning speed, which is important for improving the HIFU treatment efficiency.
authors.affiliation: Institute of Acoustics, Key Laboratory of Modern Acoustics, Ministry of Education, Nanjing University, Nanjing 210093, China. ftbo@sohu.com
authors.forename: Tingbo
authors.initials: T
authors.lastname: Fan
authors.forename: Zhenbo
authors.initials: Z
authors.lastname: Liu
authors.forename: Dong
authors.initials: D
authors.lastname: Zhang
authors.forename: Mengxing
authors.initials: M
authors.lastname: Tang
mesh_terms: D003198:Computer Simulation; D057086:High-Intensity Focused Ultrasound Ablation / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008954:Models, Biological; D009369:Neoplasms / Q000000981:diagnostic imaging*; D019047:Phantoms, Imaging; D011312:Pressure; D012815:Signal Processing, Computer-Assisted; D013696:Temperature; D014159:Transducers; D014463:Ultrasonography