Read My Leads: Subject-Specific RF Hazard Assessment and Mitigation for DBS Implants in MRI

PurposeTo develop and validate a framework for personalized, implant-specific MRI safety assessments using feedback from commercial deep brain stimulation (DBS) systems. To further use this framework to suppress RF-induced heating with minimum compromise in imaging performance. MethodsTwo off-the-shelf DBS implantable pulse generators and a commercial 8-electrode DBS lead were utilized for quantitative safety assessments. In controlled phantom experiments, (i) RF-induced voltages on the DBS lead, and (ii) temperature-dependent admittance/impedance changes in the tissue surrounding the lead's electrodes were quantified. This information was used to suppress implant-related RF heating by calculating implant-friendly imaging modes. Experimental conditions included excitations with different RF transmit coils (8-channel 3 T and 7 T head coils, 2-channel 3 T body coil), over 1000 different exposure scenarios, different implant configurations, and the use of external reference probes (E-field and temperature) for validation. Imaging performance of the applied implant-friendly mode was demonstrated in vivo on a 3 T scanner. ResultsE-fields and temperature rises around the tip electrodes could be robustly detected directly from the DBS lead. Both signals quantify the momentary patient hazard. Utilizing these measurements–recorded and wirelessly transmitted by the DBS system–tissue heating was reduced up to 99% for the same transmission power with comparable imaging performance to a conventional imaging mode. ConclusionAll the information needed for full in situ control of implant heating in MRI can be read directly from the DBS device. This approach would improve both patient safety and image quality while simultaneously reducing workload and responsibilities of the clinical personnel. B. Silemek, F. Seifert, M. Yalaz, et al., “ Read My Leads: Subject-Specific RF Hazard Assessment and Mitigation for DBS Implants in MRI,” Magnetic Resonance in Medicine (2025): Early view, https://doi.org/10.1002/mrm.70186.研究目的 开发并验证一套基于商用脑深部电刺激（deep brain stimulation, DBS）系统反馈的个性化、植入物专属的磁共振成像（magnetic resonance imaging, MRI）安全性评估框架，并进一步利用该框架在尽可能不牺牲成像性能的前提下抑制射频（radio frequency, RF）诱导的组织加热。 研究方法 本研究采用两款市售DBS植入式脉冲发生器及一款商用8电极DBS电极导线开展定量安全性评估。在受控体模实验中，我们分别量化了：① DBS电极导线上由RF诱导产生的电压；② 电极导线周围组织的温度依赖性导纳/阻抗变化。基于上述信息，通过计算适配植入物的成像模式，实现植入物相关RF加热的抑制。实验设置涵盖了不同RF发射线圈（8通道3T及7T头部线圈、2通道3T体部线圈）的激发、超过1000种不同暴露场景、不同植入物配置，并使用外部参考探针（电场（electric field, E-field）及温度探针）进行验证。我们还在3T扫描仪上开展了活体实验，验证了所采用的适配植入物成像模式的成像性能。 研究结果 可直接从DBS电极导线可靠检测到尖端电极周围的电场（electric field, E-field）及温度升高。这两类信号均可量化患者即时面临的风险。借助DBS系统记录并无线传输的上述测量数据，在保持与常规成像模式相当的成像性能前提下，相同发射功率下的组织加热量可被抑制高达99%。 研究结论 磁共振成像中植入物加热的全原位控制所需的全部信息，均可直接从DBS设备中读取。该方法可同时提升患者安全性与图像质量，并减轻临床工作人员的工作负担与职责压力。 参考文献 B. Silemek、F. Seifert、M. Yalaz 等：《读取您的电极导线：磁共振成像中DBS植入物的受试者专属RF风险评估与缓解策略》，《Magnetic Resonance in Medicine》，2025年，预刊出，https://doi.org/10.1002/mrm.70186。