Merwa Robert, Brunner Patricia, Missner Andreas, Hollaus Karl, Scharfetter Hermann
Institute for Medical Engineering, Graz University of Technology, Krenngasse 37, 8010 Graz, Austria.
Physiol Meas. 2006 May;27(5):S249-59. doi: 10.1088/0967-3334/27/5/S21. Epub 2006 Apr 24.
Magnetic induction tomography (MIT) is a technique to image the passive electrical properties (i.e. conductivity, permittivity, permeability) of biological tissues. The inverse eddy current problem is nonlinear and ill-posed, thus a Gauss-Newton one-step method in combination with four different regularization schemes is used to obtain stable solutions. Simulations with 16 excitation coils, 32 receiving coils and different spherical perturbations inside a homogeneous cylinder were computed. In order to compare the statistical properties of the reconstructed results a Monte Carlo study with a SNR of 40 dB and 20 dB was carried out. Simulated conductivity perturbations inside a homogeneous cylinder can be localized and resolved and the results prove the feasibility of difference imaging with MIT.
磁感应断层成像(MIT)是一种用于对生物组织的无源电学特性(即电导率、介电常数、磁导率)进行成像的技术。逆涡流问题是非线性且不适定的,因此采用高斯 - 牛顿一步法结合四种不同的正则化方案来获得稳定解。对一个均匀圆柱体内部具有16个激励线圈、32个接收线圈以及不同球形扰动的情况进行了模拟计算。为了比较重建结果的统计特性,开展了信噪比分别为40 dB和20 dB的蒙特卡罗研究。均匀圆柱体内模拟的电导率扰动能够被定位和分辨,结果证明了利用MIT进行差分成像的可行性。