Dipole Field Navigation: Theory and Proof of Concept
Dipole Field Navigation: Theory and Proof of Concept
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DOI：
10.1109/tro.2015.2489518
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发表时间：
2015-12-01
影响因子：
7.8
通讯作者：
Martel, Sylvain
中科院分区：
文献类型：
--
作者：
Latulippe, Maxime;Martel, Sylvain
为了实现微尺度介质在血管网络中的有效导航，需要具有高定向磁梯度的高磁场强度。到目前为止，所研究的方法只支持其中一种规范，而不能同时支持两种规范。在此，我们提出了一种称为偶极子场导航（DFN）的新方法，该方法提供高场强，在人体任何深度以超过300 mT/m的梯度将磁性剂引入饱和磁化。对于DFN，高场强是通过将患者放置在临床MRI扫描仪的隧道中来实现的，而高梯度是由放置在患者外部特定位置的较大铁磁核对扫描仪均匀场的扭曲产生的。DFN的主要挑战在于在隧道中适当放置岩心所需的方法。本文提出了第一种方法来解决反磁问题，即定位这样一组核心，使微尺度的代理商可以在血管网络中被引导通过所需的路径。作为概念的第一个证明，磁性颗粒在三维体外网络中成功地在三个连续分叉中被引导。
To achieve the effective navigation of microscale agents in the vascular network, a high magnetic field strength with high directional magnetic gradients are required. So far, the methods that have been investigated support only one of these specifications but not both. Here, we propose a new method dubbed dipole field navigation (DFN) that provides high field strength to bring magnetic agents at saturation magnetization with gradients exceeding 300 mT/m at any depth within the human body. For DFN, the high field strength is achieved by placing the patient in the tunnel of a clinical MRI scanner, while high gradients are generated by the distortions of the scanner's homogeneous field from larger ferromagnetic cores placed at specific locations outside the patient. The main challenge of DFN lies in the methods that are required to adequately place the cores in the tunnel. Here, a first method is presented to solve the inverse magnetic problem of positioning such a set of cores so that microscale agents could be guided through a desired path in the vascular network. As a first proof of concept, magnetic particles were steered successfully in three consecutive bifurcations in a 3-D in vitro network.