Nagoya Institute of Technology, Department of Electrical and Mechanical Engineering, Nagoya, Aichi 466-8555, Japan.
Center of Biomedical Physics and Information Technology, Nagoya Institute of Technology, Nagoya 466-8555, Japan.
Phys Med Biol. 2020 Dec 17;65(24):24TR03. doi: 10.1088/1361-6560/aba40d.
Transcranial magnetic stimulation (TMS) is a technique for noninvasively stimulating a brain area for therapeutic, rehabilitation treatments and neuroscience research. Despite our understanding of the physical principles and experimental developments pertaining to TMS, it is difficult to identify the exact brain target as the generated electric field exhibits a non-uniform distribution owing to the complicated and subject-dependent brain anatomy and the lack of biomarkers that can quantify the effects of TMS in most cortical areas. Computational dosimetry has progressed significantly and enables TMS assessment by computation of the induced electric field (the primary physical agent known to activate the brain neurons) in a digital representation of the human head. In this review, TMS dosimetry studies are summarised, clarifying the importance of the anatomical and human biophysical parameters and computational methods. This review shows that there is a high consensus on the importance of a detailed cortical folding representation and an accurate modelling of the surrounding cerebrospinal fluid. Recent studies have also enabled the prediction of individually optimised stimulation based on magnetic resonance imaging of the patient/subject and have attempted to understand the temporal effects of TMS at the cellular level by incorporating neural modelling. These efforts, together with the fast deployment of personalised TMS computations, will permit the adoption of TMS dosimetry as a standard procedure in medical applications.
经颅磁刺激（TMS）是一种非侵入性刺激大脑区域的技术，可用于治疗、康复治疗和神经科学研究。尽管我们了解与 TMS 相关的物理原理和实验进展，但由于复杂的、因人而异的大脑解剖结构以及缺乏可以量化 TMS 在大多数皮质区域影响的生物标志物，因此很难确定确切的大脑目标，因为产生的电场分布不均匀。计算剂量学取得了重大进展，通过计算人头部数字表示中的感应电场（已知激活大脑神经元的主要物理因子），可以实现 TMS 评估。在这篇综述中，总结了 TMS 剂量学研究，阐明了解剖学和人体生物物理参数以及计算方法的重要性。这篇综述表明，对于详细的皮质褶皱表示和周围脑脊液的精确建模，存在高度共识。最近的研究还能够基于患者/受试者的磁共振成像来预测个体优化刺激，并通过纳入神经建模来尝试了解 TMS 在细胞水平上的时间效应。这些努力，以及个性化 TMS 计算的快速部署，将允许 TMS 剂量学作为医疗应用中的标准程序。
