标题： 植入线圈中铅尖加热的建模与测量 显示英文标题

标题： Modeling and Measurement of Lead Tip Heating in Implanted Wires with Loops

摘要： 目的：理论和实验研究由射频（RF）功率沉积引起的植入导线头端加热，涉及含单个或多个环路的不同导线配置。 方法：在1.5特斯拉磁场下，测量了20根具有不同环路和直线段配置的绝缘、封闭端导线的最大温升。 实验结果与之前报道的简单指数模型和改进传输线模型的预测值进行了比较，并与长波长近似法的结果进行了对比。 结果：两种模型都能有效预测所有导线配置的导线头端温升趋势，其中改进传输线模型表现出更高的准确性。对于上下方向（S/I-取向）的导线，增加环路数量降低了整体加热；然而，当导线左右方向（R/L-取向），电场的x分量可以忽略时，额外的环路增加了整体加热。 结论：先前开发并测试于直导线上的简单指数模型和改进传输线模型无需添加额外项或进一步修改即可解释各种环路配置下的射频加热现象。这些结果扩展了模型的实用性，用于管理植入设备导线头端加热问题，并提供了有关环路和电气长度在管理植入设备射频安全性方面作用的理论见解。 显示英文摘要

摘要： Purpose: To theoretically and experimentally study implant lead tip heating caused by radiofrequency (RF) power deposition in different wire configurations that contain loop(s). Methods: Maximum temperature rise caused by RF heating was measured at 1.5T on 20 insulated, capped wires with various loop and straight segment configurations. The experimental results were compared with predictions from the previously reported simple exponential and the adapted transmission line models, as well as with a long-wavelength approximation. Results: Both models effectively predicted the trends in lead tip temperature rise for all the wire configurations, with the adapted transmission line model showing superior accuracy. For superior/inferior (S/I)-oriented wires, increasing the number of loops decreased the overall heating. However, when wires were oriented right/left (R/L) where the x-component of the electric field is negligible, additional loops increased the overall heating. Conclusion: The simple exponential and the adapted transmission line models previously developed for, and tested on, straight wires require no additional terms or further modification to account for RF heating in a variety of loop configurations. These results extend the usefulness of the models to manage implanted device lead tip heating and provide theoretical insight regarding the role of loops and electrical lengths in managing RF safety of implanted devices.