title: Simulation of thermal ablation by high-intensity focused ultrasound with temperature-dependent properties.
abstract: An integrated computational framework was developed in this study for modeling high-intensity focused ultrasound (HIFU) thermal ablation. The temperature field was obtained by solving the bioheat transfer equation (BHTE) through the finite element method; while, the thermal lesion was considered as a denatured material experiencing phase transformation and modeled with the latent heat. An equivalent attenuation coefficient, which considers the temperature-dependent properties of the target material and the ultrasound diffraction due to bubbles, was proposed in the nonlinear thermal transient analysis. Finally, a modified thermal dose formulation was proposed to predict the lesion size, shape and location. In-vitro thermal ablation experiments on transparent tissue phantoms at different energy levels were carried out to validate this computational framework. The temperature histories and lesion areas from the proposed model show good correlation with those from the in-vitro experiments.
authors.affiliation: Department of Civil Engineering, Chung Yuan Christian University, Taoyuan, Taiwan. Electronic address: cwhuang@cycu.edu.tw.
authors.forename: C W
authors.initials: CW
authors.lastname: Huang
authors.affiliation: Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital & College of Medicine, Taipei, Taiwan; Division of Medical Engineering Research, National Health Research Institutes, Miaoli, Taiwan.
authors.forename: M K
authors.initials: MK
authors.lastname: Sun
authors.affiliation: Department of Civil Engineering, Chung Yuan Christian University, Taoyuan, Taiwan.
authors.forename: B T
authors.initials: BT
authors.lastname: Chen
authors.affiliation: Department of Materials Science and Engineering, National Taiwan University, Taipei, Taiwan.
authors.forename: J
authors.initials: J
authors.lastname: Shieh
authors.affiliation: Department of Civil Engineering, National Taiwan University, Taipei, Taiwan.
authors.forename: C S
authors.initials: CS
authors.lastname: Chen
authors.affiliation: Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital & College of Medicine, Taipei, Taiwan; Division of Medical Engineering Research, National Health Research Institutes, Miaoli, Taiwan. Electronic address: wenshiang@gmail.com.
authors.forename: W S
authors.initials: WS
authors.lastname: Chen
mesh_terms: D020342:Finite Element Analysis; D057086:High-Intensity Focused Ultrasound Ablation; D020100:Hydrogels; D008954:Models, Biological; D019047:Phantoms, Imaging; D012984:Software; D013696:Temperature
chemical_list: D020100:Hydrogels
keywords: Ablation; Attenuation coefficient; High-intensity focused ultrasound (HIFU); Latent heat; Thermal dose