针对人工肛门括约肌的生物电磁相容性问题，通过对人体断层照片进行图像分割实现了组织的划分和识别，建立了包含40种生物组织的人体电磁模型.运用时域有限差分法，计算了经皮能量传输系统对生物组织产生的辐射剂量，获得了人体不同组织在该电磁场中的比吸收率分布情况，并根据国际人体电磁安全标准对其进行了深入分析.仿真结果表明，经皮能量传输系统在发射功率为1.5W，谐振频率为358kHz的实验环境下对人体组织具有良好的生物相容性.
Bio-electromagnetic compatibility for artificial anal sphincter is investigated in this paper. Through segmentation of the image, the tissues are divided and identified. Electromagnetic model of human body is established with 40 kinds of tissues. The radiation dose of the transcutaneous energy transfer system on biological tissues is calculated using the finite difference time domain (FDTD) method. The specific absorption rate distribution of different tissues is obtained in the electromagnetic field. The safety analysis is carried out according to the international standard for electromagnetic safety of human body. The simulation results show that the transcutaneous energy transfer system has good biocompatibility to human tissues when transmitting power is 1500mW and resonant frequency is 358kHz in the experimental environment.
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