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Human in-vivo brain magnetic resonance current density imaging (MRCDI)

Cihan Göksu, Lars G. Hanson, Hartwig R. Siebner, Philipp Ehses, Klaus Scheffler, Axel Thielscher
2018 NeuroImage  
Figure 2 . 16172 have demonstrated the feasibility of reliable MRCDI measurements in-vivo in the human brain at 586 a current strength of 1 mA.  ...  of current-induced 528 magnetic fields in the human brain.  ... 
doi:10.1016/j.neuroimage.2017.12.075 pmid:29288869 fatcat:eqernm2rcff5fhp3ah6hbhv7pu

Sensitivity and resolution improvement for in-vivo magnetic resonance current density imaging (MRCDI) of the human brain [article]

Cihan Goksu, Klaus Scheffler, Frodi Gregersen, Hasan H Eroglu, Rahel Heule, Hartwig R Siebner, Lars G Hanson, Axel Thielscher
2021 bioRxiv   pre-print
Purpose: Magnetic resonance current density imaging (MRCDI) combines MR brain imaging with the injection of time-varying weak currents (1-2 mA) to assess the current flow pattern in the brain.  ...  imaging of the human brain.  ...  Figure 1 . 1 Experimental set-up for human in-vivo brain MRCDI.  ... 
doi:10.1101/2021.03.23.436558 fatcat:erqd4mhi4jalzhse7busomem5q

Reconstruction of conductivity and current density images using only one component of magnetic field measurements

Jin Keun Seo, Jeong-Rock Yoon, Eung Je Woo, Ohin Kwon
2003 IEEE Transactions on Biomedical Engineering  
Magnetic resonance current density imaging (MRCDI) is to provide current density images of a subject using a magnetic resonance imaging (MRI) scanner with a current injection apparatus.  ...  Index Terms-Conductivity, current density, magnetic flux density, magnetic resonance current density imaging, magnetic resonance electrical impedance tomography.  ...  INTRODUCTION Magnetic resonance current density imaging (MRCDI) has been developed to quantitatively visualize internal current density distributions of a subject due to an injection current through surface  ... 
doi:10.1109/tbme.2003.816080 pmid:12943280 fatcat:7a7s3kxdnffsdke5324yxyvxde

Safety Evaluation of a New Setup for Transcranial Electric Stimulation during Magnetic Resonance Imaging

Fróði Gregersen, Cihan Göksu, Gregor Schaefers, Rong Xue, Axel Thielscher, Lars G. Hanson
2021 Brain Stimulation  
To optimize the stimulation setup for MR current density imaging (MRCDI) and increase maximum stimulation current, a new low-conductivity (σ = 29.4 S/m) lead wire is designed and tested.  ...  Coupling to the RF field can be reliably prevented by low-conductivity leads, enabling cable paths optimal for MRCDI.  ...  Image c) is clearly dominated by stray fields seen in image b), whereas the stray fields from leads in image e) are greatly reduced, so f) is dominated by tissue currents. F. Gregersen, C.  ... 
doi:10.1016/j.brs.2021.02.019 pmid:33706007 fatcat:j6fukd2h4zgydphickv6dmmxhy

Gradient-based magnetic resonance electrical properties imaging of brain tissues

Jiaen Liu, Xiaotong Zhang, Sebastian Schmitter, Pierre-Francois Van de Moortele, Bin He
2014 2014 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society  
Using a 7 Tesla MRI system, we report high-quality in vivo human brain electrical property images with refined structural details, which can potentially merit clinical diagnosis (such as cancer detection  ...  Electrical properties tomography (EPT) holds promise for noninvasively mapping at high spatial resolution the electrical conductivity and permittivity of biological tissues in vivo using a magnetic resonance  ...  Acknowledgments This work was supported in part by NIH RO1EB006433, RO1EB007920, R21EB017069, R21EB009133, R21EB014353, P41RR008079, P30NS057091, and U01HL117664.  ... 
doi:10.1109/embc.2014.6945010 pmid:25571378 pmcid:PMC4404311 dblp:conf/embc/LiuZSM014 fatcat:ykhrevbutbcptdjndvmu3xnjme

Recent Progress and Future Challenges in MR Electric Properties Tomography

Ulrich Katscher, Dong-Hyun Kim, Jin Keun Seo
2013 Computational and Mathematical Methods in Medicine  
MR Electric Properties Tomography (EPT) is a lately developed medical imaging modality capable of visualizing both conductivity and permittivity of the patient at the Larmor frequency usingB1maps.  ...  In MRCDI, the induced current density J produces a change of the main dc magnetic field, and only is a measurable quantity by MRI since it alters the MR phase image.  ...  At frequency below 1 kHz, Joy et al. in 1989 [2] introduced MR current density imaging (MRCDI) which aims to provide noninvasive visualization of current density J = ∇ × H inside a body by externally  ... 
doi:10.1155/2013/546562 pmid:23573170 pmcid:PMC3614062 fatcat:b3gwd77honeetc7pwas4lf2w64

Proceedings Of The 4Th Conference On Biomedical Applications Of Electrical Impedance Tomography: Abstracts [article]

William Lionheart, Richard Bayford
2003 Zenodo  
Current density distribution can be imaged using Magnetic Resonance Current Density Imaging (MRCDI) techniques.  ...  Magnetic Resonance Current Density Imaging (MRCDI) is to provide current density images of a subject using an MRI system with a current injection apparatus.  ...  Low frequency electric current flows through the extra-cellular space and either its widening or the disruption of the tight junctions (or both) will decrease the resistance.  ... 
doi:10.5281/zenodo.17924 fatcat:iniab6q6dfcdxle4a325c5hp4e

Sensitivity analysis of magnetic field measurements for magnetic resonance electrical impedance tomography (MREIT)

Cihan Göksu, Klaus Scheffler, Philipp Ehses, Lars G. Hanson, Axel Thielscher
2017 Magnetic Resonance in Medicine  
INTRODUCTION Magnetic resonance current density imaging (MRCDI) and magnetic resonance electrical impedance tomography (MREIT) are two emerging imaging modalities, which combine MRI with externally applied  ...  However, a reliable DB z,c measurement in in-vivo situations is crucial and challenging as only weak currents can be applied to the human body in the low frequency range, e.g. around 1-2 mA for brain studies  ... 
doi:10.1002/mrm.26727 pmid:28560836 fatcat:7mxt4nrmjjhz3lsfgg5lwc7tdq

Magnetic-Resonance-Based Electrical Properties Tomography: A Review

Xiaotong Zhang, Jiaen Liu, Bin He
2014 IEEE Reviews in Biomedical Engineering  
quantifying radiofrequency (RF) coil induced Specific Absorption Rate (SAR) which is a major safety concern in high-and ultrahigh-field Magnetic Resonance Imaging (MRI) applications.  ...  well as their applications in in vivo tumor detection and subject-specific SAR prediction.  ...  Acknowledgments This work was supported in part by NIH RO1EB006433, RO1EB007920, R21EB017069, R21EB009133, R21EB014353, P41RR008079, P30NS057091, and U01HL117664. The authors are grateful to Drs. P.  ... 
doi:10.1109/rbme.2013.2297206 pmid:24803104 pmcid:PMC4113345 fatcat:g74halcdmzgfjge4m3qv7mezpe

Magnetic resonance electrical impedance tomography (MREIT) for high-resolution conductivity imaging

Eung Je Woo, Jin Keun Seo
2008 Physiological Measurement  
Eng. 46 1139-49 Joy M L G, Scott G C and Henkelman R M 1989 In vivo detection of applied electric currents by magnetic resonance imaging Magn. Reson.  ...  Imaging 21 695-702 Kim H J et al 2008a In vivo electrical conductivity imaging of a canine brain using a 3 T MREIT system Physiol.  ...  Acknowledgments The authors thank collaborators at the Impedance Imaging Research Center (IIRC) in Korea for their contribution to the materials included in this review paper.  ... 
doi:10.1088/0967-3334/29/10/r01 pmid:18799834 fatcat:duwdqbz6ujhehcrorzaypioyba

CoReHA 2.0: A Software Package forIn VivoMREIT Experiments

Kiwan Jeon, Chang-Ock Lee
2013 Computational and Mathematical Methods in Medicine  
Magnetic resonance electrical impedance tomography (MREIT) is a new medical imaging modality visualizing static conductivity images of electrically conducting subjects.  ...  image.  ...  The technique involves (i) current injection into an electrically conducting object such as animal or human body through surface electrodes, (ii) measurement of induced internal magnetic flux density using  ... 
doi:10.1155/2013/941745 pmid:23509604 pmcid:PMC3595674 fatcat:sfa6uy4njzdpnagg773v5xn7ii

Magnetic Resonance Electrical Impedance Tomography (MREIT)

Jin Keun Seo, Eung Je Woo
2011 SIAM Review  
Since then, imaging techniques in MREIT have advanced rapidly and have now reached the stage of in vivo animal and human experiments.  ...  Magnetic resonance electrical impedance tomography (MREIT) is a recently developed medical imaging modality visualizing conductivity images of an electrically conducting object.  ...  The authors thank collaborators at the Impedance Imaging Research Center for their invaluable contributions.  ... 
doi:10.1137/080742932 fatcat:6duvf6tdxjedte7xxezx53qyma

Magnetic resonance electrical impedance tomography (MREIT): conductivity and current density imaging

Jin Keun Seo, Ohin Kwon, Eung Je Woo
2005 Journal of Physics, Conference Series  
Basic idea of MREIT Since late 1980s, measurements of the internal magnetic flux density due to an injection current have been studied in Magnetic Resonance Current Density Imaging (MRCDI) to visualize  ...  In MREIT, we measure the induced magnetic flux density B inside a subject due to an injection current I using an MRI scanner. Then, we may compute the internal current density J as is done in MRCDI.  ... 
doi:10.1088/1742-6596/12/1/014 fatcat:falmptuoefcrppkvbvwlfo7ykq

Optimization of magnetic flux density for fast MREIT conductivity imaging using multi-echo interleaved partial fourier acquisitions

Munish Chauhan, Woo Chul Jeong, Hyung Joong Kim, Oh In Kwon, Eung Je Woo
2013 BioMedical Engineering OnLine  
The injected current through a pair of surface electrodes induces a magnetic flux density distribution inside the imaging object, which results in additional magnetic flux density.  ...  Magnetic resonance electrical impedance tomography (MREIT) has been introduced as a non-invasive method for visualizing the internal conductivity and/or current density of an electrically conductive object  ...  The internal current density distribution has been studied in magnetic resonance current density imaging (MRCDI) by measuring the whole magnetic flux density data B = (B x , B y , B z ) [1, 2] .  ... 
doi:10.1186/1475-925x-12-82 pmid:23981409 pmcid:PMC3766253 fatcat:g7bruolfzbbotpywzkxkoorg7m

Complex B1mapping and electrical properties imaging of the human brain using a 16-channel transceiver coil at 7T

Xiaotong Zhang, Pierre-Francois Van de Moortele, Sebastian Schmitter, Bin He
2012 Magnetic Resonance in Medicine  
In this study, using a 16channel transceiver coil at 7T, based on hybrid B 1 -mapping techniques within the human brain, a complex B 1 -mapping method has been developed, and in-vivo EPs imaging of the  ...  human brain has been demonstrated by applying a logarithm-based inverse algorithm.  ...  Can Akgun for providing XFDTD electromagnetic models of the human brain; Dr. Christopher Collins, Dr. Suk-Hoon Oh and Dr. Wei Luo for EPs measurements in the phantom model, and Dr. Gang Hu, Mr.  ... 
doi:10.1002/mrm.24358 pmid:22692921 pmcid:PMC3549472 fatcat:btv2uati3nd6pk223fw3hwnh3e
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