北京生物医学工程

脑组织射频消融的有限元仿真与分析

Finite element simulation analysis of radiofrequency ablation in brain

作者：洪焦高宏建吴水才

单位：北京工业大学生命科学与生物工程学院（北京 100124）

分类号：

出版年·卷·期（页码）：2012·31·1（10-15）

摘要：

目的运用有限元方法(finite element method，FEM)模拟颅内病灶射频消融过程中的温度场分布，以合理有效利用热疗方案，提高射频消融对颅内病灶的治疗效果。方法建立电导率不变和电导率随温度变化的两种有限元模型，并对两种模型的中心温度、电场强度、热生成率、比吸收率(specific absorption rate，SAR)，以及热损伤区域进行对比分析。结果对比电导率不变的有限元模型，在电导率随温度变化的情况下，电场强度减小，电流密度增大，中心温度升高，热损伤范围增大；当消融温度接近100 ℃时电导率变化明显，其对消融效果影响较大。结论射频热疗手术中考虑随温度变化的组织参数有较高的临床参考价值。

Objective To simulate the temperature distribution during radiofrequency ablation(RFA)of intracranial lesion by the finite element method(FEM). This thermotherapy might improve the treatment effectiveness of the RFA in intracranial nidus. Methods Two finite element models including the constant electrical conductivity model and the temperature-dependent conductivity model were built，and the key parameters including central temperature，electric field intensity，heat flux，specific absorption rate(SAR)and lesion size were compared. Results In the case of the temperature-dependent conductivity，the lower electric field intensity，the higher electric current density，the higher central temperature，and the bigger lesion size were obtained. The impact of the temperature-dependent conductivity on the radiofrequency ablation operation was great， especially when the central temperature was near to 100℃. Conclusions The temperature-dependent parameters provided important clinical reference values in the intracranial radiofrequency ablation operation.

参考文献：

［1］Tungjitkusolmun S，Woo EJ，Cao H，et al. Finite element analyses of uniform current density electrodes for radio-frequency cardiac ablation［J］. IEEE Trans Biomed Eng，2001,47(1):32-40.
［2］Goldberg SN. Radiofrequency tumor ablation：principles and techniques［J］. Eur J Ultrasound,2001，13(2):129-147.
［3］Cosman E. Radiofrequency lesions［M］//. Gildenberg PL，Tasker R，eds.Textbook of stereotactic and functional neurosurgery. Kingsport：Quebecor Printing，1996:973-985
［4］王启弘，杨富明，杨世春. 射频毁损脑深部肿瘤的应用研究［J］. 功能性和立体定向神经外科杂志,1997,10(4):14-16.
［5］王梅. 肿瘤热疗的研究进展［J］. 海南医学院学报，2010，16(2):245-247.
［6］徐晓菲，白景峰,陈亚珠. 水冷式射频消融过程中水冷温度对热损伤的影响［J］.北京生物医学工程，2008，27(4）:393-395.
［7］Isaac Chang. Finite Element Analysis of Hepatic Radiofrequency Ablation Probes using Temperature-Dependent Electrical Conductivity［EB/J］. BioMed Central. BioMedical Engineering OnLine,2003.
［8］范晓筠，白景峰，陈亚珠. 单针水冷式射频消融过程中组织热损伤区域的有限元分析［J］. 中国医学物理学杂志，2007，24(3):197-199.
［9］Johansson JD， Eriksson O， Wren J，et al Radio-frequency lesioning in brain tissue with coagulation-dependent thermal conductivity：modelling，simulation and analysis of parameter influence and interaction［J］. Med Bio Eng Comput，2006，44:757-766.
［10］Pennes HH. Analysis of tissue and arterial blood temperatures in theresting human forearm［J］.J Appl Physiol，1948,1:93-122.
［11］Gabriel C，Gabriel S，Corthout E. The dielectric properties of biological tissues：I. Literature survey［J］. Physics in Medicine and Bbiology,1996，41(11):2231-2250.
［12］Duck AF. Physical properties of tissue［J］. Cambridge:The University Press，1990.
［13］Chato JC. Selected thermophysical properties of biological materials［M］. Shitzer A，Eberhart R，eds. Heat transfer in medicine and biology：analysis and applications,1985:413-418.
［14］Chachati L， Wright AS， Mahvi DM. Hepatic radiofrequency ablation with internally cooled probes：effect of coolant temperature on lesion size［J］. Ieee Transactions on Biomedical Engineering，2003,50(4):493-500.
［15］Strogyn. Equations for calculating the dielectric content of saline water［M］. IEEE Tran Microwave Theory and Tech，1971,19：733-736.
［16］Chang IA，Beard BB. Precision test apparatus for evaluating the heating pattern of radiofrequency ablation devices［J］. Medical Engineering & Physics,2002，24：633-640.

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