11. In-vivo imaging of electrical properties and electrical activity using magnetic resonance imaging (MRI): a basics guide to students and researchers (PM)

Organizers: Atul Singh Minhas, Rosalind Sadleir

Tissue electrical conductivity imaging is emerging as a popular and challenging application of MRI techniques. One MR based conductivity imaging technique, Magnetic Resonance Electrical Impedance Tomography (MREIT) has been extensively tested in phantoms and animals. However, the need for external imaging currents has hindered its acceptance in clinical diagnosis applications. Researchers working in this field are now proposing several new approaches with direct clinical significance. Neuromodulation techniques such as transcranial DC or AC stimulation (tDCS/tACS) are naturally suited to MREIT imaging, and its use to image these current flows in the brain has led to new approaches to mechanisms and practice. Conductivity can also be imaged without using current via Magnetic Resonance Electric Properties Tomography (MREPT) and Conductivity Tensor Imaging (CTI). The MREIT, MREPT, and CTI may also be used for detection of cancer and cerebral palsy in brain. Development and validation of these techniques in high field scanners requires specialized phantoms suitable for ultra-high magnetic fields. The aim of this workshop is to provide a guidance for students and researchers working in the three fields of MREIT, MREPT and CTI. The audience will learn about the setup of basic experiments, development of multi-physics models to understand conductivity contrast mechanisms, formulation and solution of electromagnetic forward and inverse problems, and new applications of these techniques.

List of Speakers

Eung Je Woo, Kyung Hee University

Electrodeless conductivity tensor imaging (CTI) using MRI

Eung Je Woo is currently Professor of Biomedical Engineering, College of Medicine, Kyung Hee University. He received BS and MS degrees in Electronic Engineering from Seoul National University in 1983 and 1985, respectively. In 1990, he received PhD degree in Electrical and Computer Engineering from the University of Wisconsin-Madison. Since 2002, he has been the Director of the Impedance Imaging Research Center (IIRC) at Kyung Hee University. His primary research interests include biomedical instrumentation and impedance imaging methods such as EIT, MREIT, MREPT and CTI. He has been the member of the KOSOMBE and IEEE EMBS for more than 30 years. He served the program chair of the WC2006 in Seoul and the IEEE EMBC17 in Jeju Island.

Hyung Joong Kim, Kyung Hee University

New contrast information on tissue condition using MR-based conductivity imaging method

Dr Kim is a Research Professor at Impedance Imaging Research Center (IIRC) in Kyung Hee University, Seoul, South Korea. His present research interests focus on the translational research of MR-based conductivity imaging from disease model animal imaging by 9.4T MRI and in vivo human imaging by 3T MRI.

Ryan J. Halter, Dartmouth College

Reconstructing Magnetic Resonance Electrical Property Tomography images using an inverse problems approach

Dr Halter is an Assistant Professor of Biomedical Engineering at Dartmouth’s Thayer School of Engineering. His present research interests focus on developing medical devices and imaging modalities that leverage the electrical properties of tissue to address clinical challenges ranging from cancer detection and surgical guidance to traumatic brain injury monitoring and cardiac health assessment.

Munish Chauhan, Arizona State University

Practical aspects of phantom and in vivo MREIT measurement and analysis

Dr Chauhan is currently a Postdoctoral Researcher at the Neuro-Electricity Laboratory, Arizona State University. His present research includes performing in-vivo imaging experiments and reconstructing magnetic flux density and conductivity maps using 800 MHz and 7T MRIs. Additionally, he is investigating the feasibility of fast MRI sequences for functional Magnetic Resonance Electric Impedance Tomography (fMREIT).

Sajib Khan, Arizona State University

DT-MREIT anisotropic conductivity reconstruction methods and challenges

Dr Sajib is currently a Postdoctoral Researcher at the Neuro-Electricity Laboratory, Arizona State University, USA. His present research focusses on in-vivo imaging of current density and electric field distribution during electrical brain stimulation.

Atul S. Minhas, Macquarie University

A multi-physics model to understand magnetohydrodynamic (MHD) effects in MREIT at ultra-high magnetic fields

Dr Minhas is a Senior Lecturer of Biomedical Engineering in the School of Engineering at Macquarie University, Sydney, Australia. He has hands on experience in developing 3Tesla wide-bore MRI system while working for Samsung Electronics at South Korea. Dr Minhas has research interest in MRI gradient/shim coil design, MRI pulse sequence programming, developing MR based tissue electrical conductivity imaging to detect brain cancer and cerebral palsy.

Rosalind J. Sadleir, Arizona State University

Construction and use of computational MREIT models from image data

Dr Sadleir is an Assistant Professor of Biomedical Engineering in the School of Biological and Health Systems Engineering at Arizona State University. Her present research interests include in-vivo imaging of electromagnetic current distributions in human heads subject to neuromodulation stimulation and functional neuroimaging based on conductivity contrast.

Sergei Turovets, Philips-EGI

Bounded EIT calibration of regional conductivities in MRI based electrical head models for EEG source localization and transcranial electrical neurostimulation

Dr. Turovets is a Senior Scientist at Philips EGI in Eugene, Oregon. His current research interests include MRI physics, biomedical engineering and physiological measurements, mathematical modeling and numerical methods in neuroscience and brain imaging.