Journal ArticleDOI
Induced current electrical impedance tomography system: experimental results and numerical simulations.
Sharon Zlochiver,Michal M. Radai,Shimon Abboud,Moshe Rosenfeld,Xiuzhen Dong,Ruigang Liu,Fusheng You,Haiyan Xiang,Xuetao Shi +8 more
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TLDR
The experimental reconstructed images were found to be indicative of the angular positioning of the conductivity perturbations, though the radial sensitivity was low, especially when using the Marquardt regularization method.Abstract:
In electrical impedance tomography (EIT), measurements of developed surface potentials due to applied currents are used for the reconstruction of the conductivity distribution. Practical implementation of EIT systems is known to be problematic due to the high sensitivity to noise of such systems, leading to a poor imaging quality. In the present study, the performance of an induced current EIT (ICEIT) system, where eddy current is applied using magnetic induction, was studied by comparing the voltage measurements to simulated data, and examining the imaging quality with respect to simulated reconstructions for several phantom configurations. A 3-coil, 32-electrode ICEIT system was built, and an iterative modified Newton-Raphson algorithm was developed for the solution of the inverse problem. The RMS norm between the simulated and the experimental voltages was found to be 0.08 +/- 0.05 mV (<3%). Two regularization methods were implemented and compared: the Marquardt regularization and the Laplacian regularization (a bounded second-derivative regularization). While the Laplacian regularization method was found to be preferred for simulated data, it resulted in distinctive spatial artifacts for measured data. The experimental reconstructed images were found to be indicative of the angular positioning of the conductivity perturbations, though the radial sensitivity was low, especially when using the Marquardt regularization method.read more
Citations
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PatentDOI
Magnetic induction tomography
TL;DR: In this article, a magnetic induction tomography (MIT) apparatus comprises an excitation signal generator (70), a primary excitation coil (50), an active reference source (175), and a signal distribution network (115).
Journal ArticleDOI
EIT reconstruction algorithms: pitfalls, challenges and recent developments
TL;DR: In this article, the authors reviewed developments, issues and challenges in electrical impedance tomography (EIT) for the 4th Conference on Biomedical Applications of Electrical Impedance Tomography, held at Manchester in 2003, focusing on the necessity for three-dimensional data collection and reconstruction, efficient solution of the forward problem, and both present and future reconstruction algorithms.
Journal ArticleDOI
A portable bio-impedance system for monitoring lung resistivity
Sharon Zlochiver,Marina Arad,Michal M. Radai,D. Barak-Shinar,H. Krief,T. Engelman,R. Ben-Yehuda,Avraham Adunsky,Shimon Abboud +8 more
TL;DR: The principles of a hybrid bio-impedance technique are implemented in a novel, lung resistivity monitoring system, to be utilized in the clinic or at home, for daily monitoring of patients suffering from pulmonary edema.
Journal ArticleDOI
Real-Time Dynamic Imaging Method for Flexible Boundary Sensor in Wearable Electrical Impedance Tomography
TL;DR: A novel real-time dynamic imaging method for flexible boundary sensors in wearable electrical impedance tomography (wearable EIT) and the boundary shape is well estimated with boundary error.
Journal ArticleDOI
Towards magnetic detection electrical impedance tomography: data acquisition and image reconstruction of current density in phantoms and in vivo
TL;DR: The development of an MD-EIT data acquisition system is described and the related image reconstruction issues are discussed and the ill-conditioned nature of the inverse problem is examined and a number of image reconstruction methods are compared.
References
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