Impedance Imaging Research Center (IIRC), Kyung Hee University

30/05/2025

On May 24th, we held our IIRC alumni gathering, where we had the honor of bidding farewell to Prof. Woo as he retired from Kyung Hee University. Prof. Woo is one of Korea’s most distinguished scientists, with a remarkable legacy of interdisciplinary contributions in the field of Biomedical Engineering, and is globally regarded as a pioneer in conductivity imaging.

This occasion also marked the formal closure of the Impedance Imaging Research Center (IIRC) as an center. While the laboratory’s research efforts will continue under the leadership of Prof. Tong In Oh, the IIRC will no longer operate as a dedicated center.

Kyung Hee University, Korea

25/12/2022

We wish you a merry Christmas and have a happy new year.

24/02/2021

Many congratulations to the new graduates from IIRC 🥳🥳🥳

We wish you a successful future ahead and very good luck with all future endeavors.

IIRC의 새로운 졸업생이 되신걸 축하합니다.

성공적인 미래와 앞으로 하시는 노력에 빛을 보시길 기원합니다.

03/09/2020

MR‐Based Electrical Conductivity Imaging of Liver Fibrosis is now available at JMRI. With a heavy heart, this was the last paper of MREIT research from IIRC.

As a pioneer and 3 decades as a leading group, IIRC bid adieu to Magnetic Resonance Electrical Impedance Tomography.

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https://onlinelibrary.wiley.com/doi/full/10.1002/jmri.27275

19/02/2020

Many congratulations to Dr Ghazal Ayoub and Dr Nitish Katoch for getting their PhD degree from IIRC at Kyung Hee University.

We wish a whole hearted wishes for their future and also hope that they excel in there future jobs.

28/06/2019

https://ieee-tmi.org/ -- IEEE-TMI (Transactions on Medical Imaging) is now one of the top 3 journals in Radiological Sciences. Following behind JACC: Cardiovascular Imaging and Medical Image Analysis. IIRC extends its congratulations remarks to the editorial team. Happy to share our most recent 2 articles in IEEE TMI.

IEEE Xplore IEEE Engineering in Medicine & Biology Society (EMBS)

Conductivity Tensor Imaging of In Vivo Human Brain and Experimental Validation using Giant Vesicle Suspension
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https://ieeexplore.ieee.org/document/8556029

In Vivo Measurement of Brain Tissue Response after Irradiation: Comparison of T2 Relaxation, Apparent Diffusion Coefficient, and Electrical Conductivity
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https://ieeexplore.ieee.org/document/8701664/

Photo Credit : IEEE-TMI

01/05/2019

Our recent article on "In Vivo Measurement of Brain Tissue Response after Irradiation: Comparison of T2 Relaxation, Apparent Diffusion Coefficient, and Electrical Conductivity" published in IEEE Transaction on Medical Imaging.

Abstract:- Radiation therapy (RT) has been widely used as a powerful treatment tool to address cancerous tissue because of its ability to control cell growth. Its ionizing radiation damages the DNA of cancerous tissues, leading to cell death. Medical imaging, however, still has limitations regarding the reliability of its assessment of tissue response and in predicting the treatment effect because of its inability to provide contrast information on the gradual, minute tissue changes after RT. A recently developed magnetic resonance (MR)-based conductivity imaging method may provide direct, highly sensitive information on this tissue response because its contrast mechanism is based on the concentration and mobility of ions in intracellular- and extracellular spaces. In this feasibility study, we applied T2-weighted, diffusion-weighted, and electrical conductivity imaging to mouse brain, thus using MR imaging to map the tissue response after radiation exposure. To evaluate the degree of response, we measured the T2 relaxation, apparent diffusion coefficient (ADC), and electrical conductivity of brain tissues before and after irradiation. The conductivity images, which showed significantly higher sensitivity than other MR imaging methods, indicated that the contrast is distinguishable in different ways at different areas of the brain. Future studies will focus on verifying these results and the long-term evaluation of conductivity changes using various irradiation methods for clinical application.

Radiation therapy (RT) has been widely used as a powerful treatment tool to address cancerous tissue because of its ability to control cell growth. Its ion

30/01/2019

Our recent paper on "EIT Imaging of Upper Airway to Estimate Its Size and Shape Changes During Obstructive Sleep Apnea" published in Annals of Biomedical Engineering Journal. Many congratulations to Ghazal Ayoub for her first International publication with IIRC.

Abstract:- Noninvasive continuous imaging of the upper airway during natural sleep was conducted for patients with obstructive sleep apnea (OSA) using the electrical impedance tomography (EIT) technique. A safe amount of alternating current (AC) was injected into the lower head through multiple surface electrodes. Since the air is an electrical insulator, upper airway narrowing during OSA altered internal current pathways and changed the induced voltage distribution. Since the measured voltage data from the surface of the lower head were influenced not only by upper airway narrowing but respiratory motions, head motions, and blood flows, we developed a pre-processing algorithm to extract the voltage component originated from upper airway closing and opening. Using an EIT image reconstruction algorithm, time-series of EIT images of the upper airway were produced with a temporal resolution of 50 frames per second. Applying a postprocessing algorithm to the reconstructed EIT images, we could extract quantitative information about changes in the size and shape during upper airway closing and opening. Results of the clinical studies with seven normal subjects and ten OSA patients show the feasibility of the new method for OSA phenotyping and treatment planning.

Noninvasive continuous imaging of the upper airway during natural sleep was conducted for patients with obstructive sleep apnea (OSA) using the electrical impedance tomography (EIT) technique. A safe...

27/03/2018

Electrical impedance tomography (EIT) allows functional imaging of regional lung ventilation for real-time bedside monitoring of mechanically ventilated patients. Images showing time-changes of regional air distributions in the lungs can provide valuable diagnostic information for lung protective mechanical ventilation. This paper reports in vivo porcine imaging experiments of regional lung ventilation using a 16-channel parallel EIT system. Real-time time-difference chest images of 10 animals were reconstructed during mechanical ventilation with a temporal resolution of 50 frames/s. Analyzing the images together with the airway volume-pressure information from the mechanical ventilator, we could successfully produce regional compliance images at PEEP (positive end-expiratory pressure) titration. From in vivo animal experiments, we propose the method as a continuous monitoring means for LPV (lung protective ventilation).

Electrical impedance tomography (EIT) allows functional imaging of regional lung ventilation for real-time bedside monitoring of mechanically ventilated pa

27/03/2018

Our recent article in nature' scientific reports!

Techniques for electrical brain stimulation (EBS), in which weak electrical stimulation is applied to the brain, have been extensively studied in various therapeutic brain functional applications. The extracellular fluid in the brain is a complex electrolyte that is composed of different types of ions, such as sodium (Na+), potassium (K+), and calcium (Ca+). Abnormal levels of electrolytes can cause a variety of pathological disorders. In this paper, we present a novel technique to visualize the total electrolyte concentration in the extracellular compartment of biological tissues.
The electrical conductivity of biological tissues can be expressed as a product of the concentration and the mobility of the ions. Magnetic resonance electrical impedance tomography (MREIT) investigates the electrical properties in a region of interest (ROI) at low frequencies (below 1 kHz) by injecting currents into the brain region. Combining with diffusion tensor MRI (DT-MRI), we analyze the relationship between the concentration of ions and the electrical properties extracted from the magnetic flux density measurements using the MREIT technique. By measuring the magnetic flux density induced by EBS, we propose a fast non-iterative technique to visualize the total extracellular electrolyte concentration (EEC), which is a fundamental component of the conductivity. The proposed technique directly recovers the total EEC distribution associated with the water transport mobility tensor.

Article

19/12/2017

Impedance Imaging Research Center & BiLab, Winter Workshop 2017.

Date:- 15 Dec, 2017
Venue:- HilliWilli Park, Heong-Seong, Kangwon-Do.