摘要
背景:基于人体组织的导电特性,研究微弱电流耦合信号在人体内的传输特性,对实现植入式医疗仪器的人体充电和通信具有重要意义。目的:分析微弱电流耦合信号在人体上臂的分布及衰减情况。方法:将人体上臂抽象成由皮肤、脂肪、肌肉、骨骼4层组织构成的同心圆柱体,采用有限元方法建立微弱电流耦合信号在上臂传输的准静态场模型,分析了多种情况下模型中电流密度的分布,并将体表电位的衰减率与仿真结果进行比较。结果与结论:仿真结果表明肌肉层是人体内耦合电流传导的主要路径,皮肤层中的电流随频率提高而增大;人体内的传导电流远大于位移电流,但随频率的提高,位移电流逐步增大,传导电流减小;皮肤干湿程度对肌肉层中总电流密度大小有一定影响,湿皮肤时肌肉层中总的电流密度大于干皮肤时的情况;耦合电流的体表电位具有较大衰减,随频率提高成一定的高通特性,且是否考虑人体组织电容效应对建模的准确性具有显著影响;人体实验与仿真实验结果具有较好的一致性。
BACKGROUND: Research the features of feeble coupling current signal transmitting through the human body based on the conductive character of the human tissues is important for the charging and communicating of the implantable medical devices. OBJECTIVE: To analyze the distribution and attenuation when the feeble current coupling signal transmitting within the human limb. METHODS: The human limb was abstracted to a four layers cylinder, including the skin, fat, muscle and bone. The quasi-static model was formed and analyzed via the finite element method. The simulation and the in vivo experiment were carried out to insight the distribution of the current density and compare decay rate of potential on body surface with the simulation results. RESULTS AND CONCLUSION: The simulation results indicated that the muscle was the major path of the coupling current, the part of current in the skin was increasing with the frequency and the conductive current was much more than the displace current. However, the displace current increased while the frequency increasing, yet the conductive current decreased. Moreover, the current density in the wet skin was greater than the dry skin case. The attenuation of the body surface had a high pass filter character with the frequency. And the capacity effect of the tissues had obvious influence on the attenuation. Finally, the in vivo experiment matched well with the simulation results.
出处
《中国组织工程研究与临床康复》
CAS
CSCD
北大核心
2011年第52期9738-9741,共4页
Journal of Clinical Rehabilitative Tissue Engineering Research
基金
国家自然科学基金(51047001)
福建省自然科学基金(2011J05077)
福建省教育厅项目(JK2010006)
澳门科学发展基金(014/2007/A1
063/2009/A
024/2009/A1)~~