电极间距与电极直径对恒功率下双极射频熔脂效果影响的研究

doi:10.3969/j.issn.0258-8021.2020.05.007

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Abstract So far there is no uniform specification for some design parameters of bipolar radiofrequency (RF) devices for noninvasive treatment of local fat accumulation. In this work,the finite element method and external experiment were used to analyze the influence of different parameters on the fat melting effect of tissues in bipolar RF,seeking for the fat melting configuration with a large range of fat melting effect without causing thermal damage to skin layer as far as possible. The finite element analysis of thermoelectric coupling of biological tissues was carried out by COMSOL Multiphysics. To verify the validity of the model,a self-developed single-channel bipolar RF output device was used to perform RF output of pig abdominal tissues. The results of finite element analysis showed that the final temperature of the skin layer was lower than the thermal damage threshold temperature and part of the fat layer was in the thermal damage area under the fat melting configuration with the power of 10 W,the diameter of the electrode sphere of 3,5,8 mm and electrode spacing of 2 and 3 cm after 30 min heating with bipolar RF;the domain point probe showed that the temperature curve in the thermal damage area of the fat layer met the requirement of the fat melting temperature. The temperature distribution in tissues under bipolar RF heating was significantly affected by different fat melting configurations. At a power of 10 W,when using a spherical electrode with a diameter of 8 mm and pressing the skin to a depth of 1 mm,under the condition of electrode spacing of 2 and 3 cm,the largest area of continuous thermal damage area and spot-shaped thermal damage area within the fat layer will be generated,and the area of thermal damage area is 2.84 and 2.55 cm²,respectively.External experiments with the same fat melting configuration showed that the final temperature of the thermocouple probe at the same position as the tissue model was 0.92±0.43℃ different from that of the corresponding domain point probe. The finite element analysis results were consistent with the experimental results. According to the results of simulation and experimental validation,the above configuration made the bipolar RF not cause thermal damage to the skin layer,at the same time while generate effective thermal damage area in the fat layer. The temperature in the thermal damage area could meet the requirement of the fat melting temperature. The reasonableconfiguration is a critical factor for the success of bipolar RF fat melting.

Key words： bipolar RF fat melting finite element analysis constant power

Received: 09 September 2019

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R318

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	Articles by authors
	Zang Lianru
	Zhou Yu
	Kang Jia
	Lin Haixiao
	Li Yuan
	Xue Yinmin

Cite this article:

Zang Lianru,Zhou Yu,Kang Jia, et al. Study on the Effect of Electrode Spacing and Electrode Diameter on Bipolar Radiofrequency Fat Melting at Constant Power[J]. Chinese Journal of Biomedical Engineering, 2020, 39(5): 566-576.

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http://cjbme.csbme.org/EN/10.3969/j.issn.0258-8021.2020.05.007 OR http://cjbme.csbme.org/EN/Y2020/V39/I5/566

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