  Magnetic resonance imaging (MRI) based electrical properties tomography (EPT)
is the quantification of the conductivity and permittivity of different
tissues. These electrical properties can be obtained through different
reconstruction methods and can be used as a contrast mechanism. The work
presented here continues from the two-dimensional CSI-EPT algorithm which was
shown to work with two-dimensional Matlab based simulations. The existing
CSI-EPT algorithm is reformulated to use the transceive phase rather than
relying on the transceive phase assumption. This is achieved by implementing a
forward problem, computing the receive phase, into the inverse minimization
problem, i.e. retrieving the electrical properties. Furthermore, the radio
frequency (RF) shield is numerically implemented to model the RF fields inside
the MRI more accurately. Afterwards, the algorithm is tested with
three-dimensional FDTD simulations to investigate if the two-dimensional
CSI-EPT can retrieve the electrical properties for three-dimensional RF fields.
Finally, an MR experiment with a phantom is performed to show the potential for
this method. From the results of the two-dimensional Matlab simulations it is
seen that CSI-EPT can reconstruct the electrical properties using MRI
accessible quantities. In the three-dimensional simulations it is observed that
the electrical properties are underestimated, nonetheless, CSI-EPT is more
precise than the standard Helmholtz based methods. Finally, the first CSI-EPT
results using measured data are shown. The results for the reconstruction using
measured data were of the same quality as the results from the FDTD simulation.
