韩国庆熙大学Eung Je Woo教授学术报告
韩国庆熙大学Eung Je Woo教授学术报告
报告题目：Bioelectromagnetism and Electrical Impedance Imaging
报 告 人：Eung Je Woo（韩国）
The human body is an electrically conducting object withvarious ions and charge-carrying molecules in complicated structures of cells, tissues, and electrolytes. Endogenous currents are generated from excitable cells and exogenous currents can be injected or induced by man-made devices. Inside the human body, there exist electric and magnetic field distributions, which arecommonly expressed as voltage, current density, and magnetic flux density. Bioelectromagnetism is to study the interplays among these quantities related with structure, pathology, function, and metabolism of cells, tissues, and organs.
There are numerous research opportunities and challenges when we view bioelectromagnetism as a tool for bioimaging.We should non-invasivelymeasure the voltage, current, and magnetic flux densityfrom the body, tissue sample, or culture with high signal-to-noise ratio and sensitivity. Innovative new sensing methodsare being developed including voltage-sensitive dyes and optical devices as well as electrodes and coils with various configurations. Not only presenting and analyzing these measured data as images, we can also extract other quantities, of which information is embedded in the data, such as electrical conductivity and endogenic neuronal current. Since this requires solutions of nonlinear inverse problems, mathematical analyses and image reconstruction algorithms are needed.
I will review two imaging methods in bioelectromagnetism: electrical impedance tomography (EIT) and magnetic resonance electrical impedance tomography (MREIT). Applications of EIT includereal-time microscopic conductivity imaging of cells and tissues as well as macroscopic conductivity imaging of the head, lungs, and breast. For MREIT, I will explain how to utilize an MRI scanner to produce high-resolution conductivity and current density images. Its potential applications may include early-stage tumor imaging, temperature imaging, and current density imaging during deep brain stimulation (DBS) and transcranial dc stimulation (tDCS). As a long-term research goal, I will discuss multi-physics direct functional neuroimaging methods utilizing all measurable bioelectromagnetic quantities from the surface and also inside of the head.