相邻骨科植入物的磁共振射频致热耦合效应作用机理  

Investigation of Coupling Effect for Adjacent Orthopedic Implants on MRI Radio-Frequency Heating

作　　者：国然 汪志超 王晶 李铖铃 李永华 胡晟 GUO Ran;WANG Zhichao;WANG Jing;LI Chengling;LI Yonghua;HU Sheng(Shanghai Institute of Medical Device Testing,Shanghai,201318;Center for Medical Device Evaluation,NMPA,Beijing,100081;NMPA Key Laboratory for Medical Electrical Equipment,Shanghai,201318;NMPA Key Laboratory for Respiratory and Anaesthetic Equipment,Shanghai,201318)

机构地区：[1]上海市医疗器械检验研究院,上海市201318 [2]国家药品监督管理局医疗器械技术审评中心,北京市100081 [3]国家药品监督管理局医用电气设备重点实验室,上海市201318 [4]国家药品监督管理局呼吸麻醉设备重点实验室,上海市201318

出　　处：《中国医疗器械杂志》2024年第5期478-485,共8页Chinese Journal of Medical Instrumentation

基　　金：上海市2021年度“科技创新行动计划”自然科学基金项目申报指南/面上项目(21ZR1459600);上海市2022年度“科技创新行动计划”技术标准项目申报指南/共性关键技术标准研究(22DZ2202800)。

摘　　要：该文研究了1.5 T/3.0 T磁共振(magnetic resonance imaging,MRI)环境下2个相邻的骨科植入物的射频场相互耦合对射频致热的作用。当患者佩戴多个相邻的植入物时,这些植入物之间的相互作用可能会增加射频致热。采用骨板和骨钉作为例子,通过基于惠更斯原理的数值模拟计算并提取热点位置的入射和散射电场向量的振幅和方向,以分析其他相邻植入物的影响。结果表明,不仅入射场的存在会导致强耦合效应,强散射场也会起作用,通过惠更斯源可以得到器械之间产生的一阶和二阶散射场,如果在一定区域内,一阶和二阶电场项相互叠加,则双植入物系统的射频致热风险会增加。This paper investigates the mechanism of radio-frequency(RF)heating that occurs when two adjacent orthopedic implants are present together under magnetic resonance imaging(MRI)at 1.5 Tesla and 3.0 Tesla.When a patient has multiple implants close to each other,interactions between the implants may increase RF heating.Typical generic interlocking plate and antibiotic nail implants are adopted as examples.To analyze the effect of adjacent implants,the amplitude and direction of incident and scattering vector electric fields at the hot spot position are calculated and extracted using numerical simulation based on Huygens principle.It is shown that a strong coupling effect occurs due to the existence of both the incident field and a strong scattering field.Huygens principle can be used to obtain the first and second order scattering fields generated between implants.If the first-and second-order electric field terms are summed within a certain region,the RF-induced heating of this dual-implant system increases.

关 键 词：时域有限差分法 惠更斯源 磁共振成像 骨科植入物 射频致热 耦合作用 

分 类 号：R318[医药卫生—生物医学工程] TP273[医药卫生—基础医学]