A DUAL MODALITY SYSTEM FOR HIGH RESOLUTION-TRUE CONDUCTIVITY IMAGING

In this study, a dual modality imaging system which utilises the magnetic flux density measurements, acquired using Magnetic Resonance Current Density Imaging (MRCDI) techniques, and the surface potential measurements, obtained from conventional Electrical Impedance Tomography (EIT) techniques, to reconstruct high resolution absolute conductivity images. An iterative algorithm is developed to minimise the difference between the current densities calculated based on the potential and the magnetic field measurements. The proposed technique is tested on simulated data with/without noise. The conductivity error is approximately 5% with noise free data and 13% when 10% noise is added to the measurements. The spatial resolution is limited by the worst of the finite element size or half the MRI resolution.

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