Wang Yu, Guo Ran, Hu Wei, Jiang Jay, Kainz Wolfgang, Chen Ji
Annu Int Conf IEEE Eng Med Biol Soc. 2021 Nov;2021:7412-7415. doi: 10.1109/EMBC46164.2021.9630892.
During Magnetic Resonance (MR) scans, abandoned leads from active implantable medical devices (AIMDs) can experience excessive heating near the lead-tip, depending on the types of termination applied to the proximal end. The influence of different proximal treatments, i.e., (i) freely exposed in the tissue, (ii) capped with metallic material, and (iii) capped with plastic material on the RF-induced heating are studied. Abandoned leads from a sacral neuromodulation (SNM) system were investigated in this study. The device models, i.e., the transfer functions, for different proximal treatments were developed. These models are then used to assess the in-vivo lead-tip heating inside four virtual human models (FATS, Duke, Ella, and Billie). The RF-induced heating from these abandoned leads with different proximal end treatments are compared with the lead-tip heating of the original AIMD system. The maximum lead-tip heating for abandoned leads using metal cap at the proximal end is lower than that from the original intact AIMD system. Abandoned leads with plastic cap treatment at the proximal end will lead to an average in-vivo temperature that is 3.5 times higher than that from the original intact AIMD system. Therefore, from this study and in terms of the RF-induced heating, the abandoned leads with metallic cap treatment at the proximal end can maintain the MR conditionality of the original AIMD system.Clinical Relevance- The different treatments of proximal end of the abandoned leads from AIMD are studied to ensure that MR Conditional AIMD leads remain MR Conditional when the leads are abandoned in the patients.
在磁共振（MR）扫描期间，有源植入式医疗设备（AIMD）的废弃导线在靠近导线尖端处可能会出现过度发热，这取决于应用于近端的终端类型。研究了不同近端处理方式，即（i）在组织中自由暴露、（ii）用金属材料覆盖以及（iii）用塑料材料覆盖对射频感应加热的影响。本研究对骶神经调节（SNM）系统的废弃导线进行了研究。针对不同近端处理方式建立了设备模型，即传递函数。然后使用这些模型评估四个虚拟人体模型（FATS、Duke、Ella和Billie）体内导线尖端的发热情况。将这些采用不同近端处理方式的废弃导线的射频感应加热与原始AIMD系统的导线尖端发热进行比较。近端使用金属帽的废弃导线的最大导线尖端发热低于原始完整AIMD系统。近端采用塑料帽处理的废弃导线会导致体内平均温度比原始完整AIMD系统高3.5倍。因此，从本研究以及射频感应加热的角度来看，近端采用金属帽处理的废弃导线可以保持原始AIMD系统的磁共振条件性。临床相关性——研究了AIMD废弃导线近端的不同处理方式，以确保当导线在患者体内废弃时，磁共振条件性AIMD导线仍保持磁共振条件性。
