Abstract：
Magnetic nanoparticle hyperthermia (MNPH) has emerged as a promising cancer treatment that complements conventional ionizing radiation and chemotherapy. MNPH involves injecting iron-oxide nanoparticles into the tumor and exposing it to an alternating magnetic field (AMF). Iron oxide nanoparticles produce heat when exposed to radiofrequency AMF due to hysteresis loss. Minimizing the non-specific heating in human tissues caused by exposure to AMF is crucial. A pulse-width-modulated AMF has been shown to minimize eddy-current heating in superficial tissues. This project developed a control strategy based on a simplified mathematical model in MATLAB SIMULINK®to minimize eddy current heating while maintaining a therapeutic temperature in the tumor. A minimum tumor temperature of 43 [°C] is required for at least 30 [min] for effective hyperthermia, while maintaining the surrounding healthy tissues below 39 [°C]. A model predictive control (MPC) algorithm was used to reach the target temperature within approximately 100 [s]. As a constrained MPC approach, a maximum AMF amplitude of 36 [kA/m] and increment of 5 [kA/m/s] were applied. MPC utilized the AMF amplitude as an input and incorporated the open-loop response of the eddy current heating in its dynamic matrix. A conventional proportional integral (PI) controller was implemented and compared with the MPC performance. The results showed that MPC had a faster response (30 [s]) with minimal overshoot (1.4 [%]) than PI controller (115 [s] and 5.7 [%]) response. In addition, the MPC method performed better than the structured PI controller in its ability to handle constraints and changes in process parameters.
摘要：
磁性纳米粒子热疗（MNPH）已成为一种有前途的癌症治疗方法，可补充常规的电离辐射和化学疗法。MNPH涉及将氧化铁纳米颗粒注射到肿瘤中并暴露于交变磁场(AMF)。氧化铁纳米颗粒在暴露于射频AMF时由于磁滞损耗而产生热量。将人体组织暴露于AMF会通过感应涡流在组织中引起非特异性加热，必须最小化。已显示脉冲宽度调制的AMF可最大程度地减少表面组织中的涡流加热。该项目基于MATLABSIMULINK®中的简化数学模型开发了一种控制策略，以最大限度地减少涡流加热，同时保持肿瘤的治疗温度。需要43[°C]肿瘤温度的最低肿瘤温度至少30[min],同时保持周围健康组织低于39[°C]。模型预测控制(MPC)算法用于在大约100[s]内达到目标温度。作为一种受约束的MPC方法，施加36[kA/m]的最大AMF振幅和5[kA/m/s]的增量。MPC使用AMF振幅作为输入，并在其动态矩阵中使用涡流加热的开环响应。实现了传统的比例积分（PI）控制器，并将其与MPC性能进行了比较。结果显示,与PI(115[s]和5.7[%])响应相比,MPC具有更快的响应(30[s])和最小的过冲(1.4[%])。此外,MPC方法在处理过程参数的约束和变化方面比结构化PI控制器性能更好。
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