Feldkamp Joe R, Quirk Stephen
Kimberly-Clark Corporation, Neenah, Wisconsin, United States.
Kimberly-Clark Corporation, Roswell, Georgia, United States.
J Med Imaging (Bellingham). 2017 Apr;4(2):023504. doi: 10.1117/1.JMI.4.2.023504. Epub 2017 Jun 16.
Recent work has shown that single-coil, magnetic induction tomography (MIT) is useful for visualizing three-dimensional electrical conductivity distributions within biological targets. Coil-induced eddy currents and the associated secondary field are detected as an inductive loss while the coil is relocated to several unique positions and orientations near a target. Image reconstruction is then accomplished by inversion of a convolution integral that quantitatively maps inductive loss with conductivity. Previously, coil position and orientation had to be established by a template, which required assignment of fixed locations for the coil to visit. Here, our existing device is modified so that coil position and orientation are optically tracked while measuring inductive loss. Optical tracking is accomplished via a set of infrared reflective spheres mounted on the same enclosure that supports the coil. The coil center can be tracked with submillimeter accuracy while orientation angle is known to within a fraction of a degree. This work illustrates the use of single-coil MIT in full, position-orientation-tracked scan mode while imaging laboratory phantoms consisting of features having biologically relevant conductivity.
最近的研究表明，单线圈磁感应断层扫描（MIT）可用于可视化生物目标内的三维电导率分布。当线圈重新定位到目标附近的几个独特位置和方向时，线圈感应的涡流和相关的二次场被检测为感应损耗。然后通过对卷积积分进行反演来完成图像重建，该卷积积分将感应损耗与电导率进行定量映射。以前，线圈的位置和方向必须通过模板来确定，这需要为线圈指定固定的访问位置。在这里，我们对现有的设备进行了改进，以便在测量感应损耗时对线圈的位置和方向进行光学跟踪。光学跟踪是通过安装在支撑线圈的同一外壳上的一组红外反射球来完成的。线圈中心可以以亚毫米的精度进行跟踪，而方向角的精度可达几分之一度。这项工作展示了单线圈MIT在全位置-方向跟踪扫描模式下的应用，同时对由具有生物相关电导率特征的实验室模型进行成像。
