title: Effects of an implant on temperature distribution in tissue during ultrasound diathermy.
abstract: The effects of an implant on temperature distribution in a tissue-mimicking hydrogel phantom during the application of therapeutic ultrasound were investigated. In vitro experiments were conducted to compare the influences of plastic and metal implants on ultrasound diathermy and to calibrate parameters in finite element simulation models. The temperature histories and characteristics of the opaque (denatured) areas in the hydrogel phantoms predicted by the numerical simulations show good correlation with those observed in the in vitro experiments. This study provides an insight into the temperature profile in the vicinity of an implant by therapeutic ultrasound heating typically used for physiotherapy. A parametric study was conducted through numerical simulations to investigate the effects of several factors, such as implant material type, ultrasound operation frequency, implant thickness and tissue thickness on the temperature distribution in the hydrogel phantom. The results indicate that the implant material type and implant thickness are the main parameters influencing the temperature distribution. In addition, once the implant material and ultrasound operation frequency are chosen, an optimal implant thickness can be obtained so as to avoid overheating injuries in tissue.
authors.affiliation: Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, Miaoli, Taiwan.
authors.forename: Ming-Kuan
authors.initials: MK
authors.lastname: Sun
authors.affiliation: Department of Materials Science and Engineering, National Taiwan University, Taipei, Taiwan.
authors.forename: Jay
authors.initials: J
authors.lastname: Shieh
authors.affiliation: Department of Civil Engineering, National Taiwan University, Taipei, Taiwan.
authors.forename: Chuin-Shan
authors.initials: CS
authors.lastname: Chen
authors.affiliation: Department of Orthopedic Surgery, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Hongsen
authors.initials: H
authors.lastname: Chiang
authors.affiliation: Department of Civil Engineering, Chung Yuan Christian University, Taoyuan, Taiwan. Electronic address: cwhuang@cycu.edu.tw.
authors.forename: Chang-Wei
authors.initials: CW
authors.lastname: Huang
authors.affiliation: Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, Miaoli, Taiwan; Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital Hsin-Chu Branch, Hsinchu, Taiwan. Electronic address: wenshiang@gmail.com.
authors.forename: Wen-Shiang
authors.initials: WS
authors.lastname: Chen
mesh_terms: D003198:Computer Simulation; D008954:Models, Biological; D019047:Phantoms, Imaging; D013696:Temperature; D014464:Ultrasonic Therapy
keywords: Finite element simulation; Implant; In vitro experiments; Temperature distribution; Ultrasound diathermy