Fast imaging for magnetic resonance electrical impedance tomography.

In magnetic resonance electrical impedance tomography (MREIT), currents are injected into an object, the resulting magnetic flux density is measured using MRI, and the conductivity distribution reconstructed using these MRI data. The relatively long acquisition times of conventional MREIT methods limit the signal averaging rate and are susceptible to motion artifacts. In this study, we reconstructed the conductivity distribution of an agarose gel phantom from data acquired in under a minute using a single-shot, spin echo, echo planar imaging (SS-SEPI) pulse sequence. The results demonstrate that SS-SEPI can be used for MREIT data acquisition.

[1]  M. Buonocore,et al.  Ghost artifact reduction for echo planar imaging using image phase correction , 1997, Magnetic resonance in medicine.

[2]  Y. Birgül,et al.  Use of the Magnetic Field Generated by the Internal Distribution of Injected Currents for Electrical Impedance Tomography (MR-EIT) , 1998 .

[3]  D C Barber,et al.  Theoretical limits to sensitivity and resolution in impedance imaging. , 1987, Clinical physics and physiological measurement : an official journal of the Hospital Physicists' Association, Deutsche Gesellschaft fur Medizinische Physik and the European Federation of Organisations for Medical Physics.

[4]  Ohin Kwon,et al.  Magnetic resonance electrical impedance tomography (MREIT): simulation study of J-substitution algorithm , 2002, IEEE Transactions on Biomedical Engineering.

[5]  Ohin Kwon,et al.  Electrical conductivity imaging using gradient Bz decomposition algorithm in magnetic resonance electrical impedance tomography (MREIT) , 2004, IEEE Trans. Medical Imaging.

[6]  Ohin Kwon,et al.  Reconstruction of conductivity and current density images using only one component of magnetic field measurements , 2003, IEEE Transactions on Biomedical Engineering.

[7]  Z H Cho,et al.  Limits to signal-to-noise improvement by FID averaging in NMR imaging. , 1984, Physics in medicine and biology.

[8]  David R. Wozny,et al.  The electrical conductivity of human cerebrospinal fluid at body temperature , 1997, IEEE Transactions on Biomedical Engineering.

[9]  Ohin Kwon,et al.  Static conductivity imaging using variational gradient Bz algorithm in magnetic resonance electrical impedance tomography. , 2004, Physiological measurement.

[10]  Ozlem Birgul,et al.  In vivo MRI electrical impedance tomography (MREIT) of tumors. , 2006, Technology in cancer research & treatment.

[11]  Y Ziya Ider,et al.  Algebraic reconstruction for 3D magnetic resonance-electrical impedance tomography (MREIT) using one component of magnetic flux density. , 2004, Physiological measurement.

[12]  Gene H. Golub,et al.  Tikhonov Regularization and Total Least Squares , 1999, SIAM J. Matrix Anal. Appl..

[13]  Y. Z. Ider,et al.  Experimental results for 2D magnetic resonance electrical impedance tomography (MR-EIT) using magnetic flux density in one direction. , 2003, Physics in medicine and biology.

[14]  Byung Il Lee,et al.  Electrical conductivity images of biological tissue phantoms in MREIT. , 2005, Physiological measurement.

[15]  R M Henkelman,et al.  Measurement of nonuniform current density by magnetic resonance. , 1991, IEEE transactions on medical imaging.

[16]  R. Henkelman,et al.  RF Current Density Imaging in Homogeneous Media , 1992, Magnetic resonance in medicine.

[17]  Yusuf Ziya Ider,et al.  Measurement of AC magnetic field distribution using magnetic resonance imaging , 1997, IEEE Transactions on Medical Imaging.

[18]  Orhan Nalcioglu,et al.  A simple simultaneous geometric and intensity correction method for echo-planar imaging by EPI-based phase modulation , 2003, IEEE Transactions on Medical Imaging.

[19]  Andrew A. Maudsley,et al.  Magnetic field measurement by NMR imaging , 1984 .

[20]  Ozlem Birgul,et al.  Resolution and Contrast in Magnetic Resonance Electrical Impedance Tomography (MREIT) and its Application to Cancer Imaging , 2004, Technology in cancer research & treatment.

[21]  R. Henkelman,et al.  Sensitivity of magnetic-resonance current-density imaging , 1992 .

[22]  Ozlem Birgul,et al.  Measurement of ion diffusion using magnetic resonance electrical impedance tomography , 2006, Physics in medicine and biology.

[23]  F Demsar,et al.  Magnetic resonance imaging of alternating electric currents. , 2001, Magnetic resonance imaging.

[24]  J. Reddy An introduction to the finite element method , 1989 .

[25]  Ozlem Birgul,et al.  Contrast and spatial resolution in MREIT using low amplitude current , 2006, Physics in medicine and biology.