scholarly journals Improved system for identifying biological tissue temperature using electrical impedance tomography

2018 ◽  
Vol 158 ◽  
pp. 01019 ◽  
Author(s):  
Evgeniy Korolyuk ◽  
Konstantin Brazovskii
Keyword(s):  
Electrical Impedance ◽  
Saline Water ◽  
Broad Band ◽  
Experimental Studies ◽  
Impedance Spectrum ◽  
Target Object ◽  
Tissue Temperature ◽  
Band Spectrum ◽  
Measuring Chamber ◽  
Impedance Tomography

This paper proposes a cheap and compact medical system that determines the temperature of an object using broadband impedance tomography. This system can be used in medicine to visualize ice structure in tissue during cryosurgical operations, as well as for fault diagnosis and location in studied industrial objects. These effects are achieved by measuring electrical impedance between electrode pairs in the measuring chamber. The assembled prototype is compact, consumes little power, and allows to non-invasively determine the impedance of a target object in real time. The research included experimental studies to determine the dependence of the impedance spectrum of saline water and muscle tissue on temperature in broad band spectrum, which allowed to obtain the dependence of total electrical impedance of target objects on temperature.

scholarly journals Assessment of the Spatial Distribution of Moisture Content in Granular Material Using Electrical Impedance Tomography

Sensors ◽  
2019 ◽  
Vol 19 (12) ◽  
pp. 2807 ◽  
Author(s):  
Jan Porzuczek
Keyword(s):  
Spatial Distribution ◽  
Moisture Content ◽  
Granular Material ◽  
Electrical Impedance Tomography ◽  
Electrical Impedance ◽  
Optical Tomography ◽  
Experimental Studies ◽  
Impedance Tomography ◽  
Wide Range ◽  
Voltage Signal

This paper presents a method for the online determination of the spatial distribution of the moisture content in granular material. It might be essential for the monitoring and optimal control of, for example, drying processes. The proposed method utilizes Electrical Impedance Tomography (EIT). As an exemplary material for experimental research, the black chokeberry (Aronia melanocarpa) was used. The relationship between the electrical impedance of the chokeberry and its moisture content was determined for a wide range of frequencies (20 Hz–200 kHz). The EIT research consisted of both simulation and experimental investigation. Experimental studies of the spatial distribution of the moisture content were performed in a cylindrical vessel equipped with 8 electrodes circumferentially arranged. The voltage signal from the electrodes was acquired simultaneously using the data acquisition module. Due to the high impedance of the chokeberries, exceeding 109 Ω for the dried matter, extraordinary instrumentation was necessary to be applied. On the other hand, raw chokeberry was characterized by a several orders of magnitude lower impedance (103–104 Ω), especially for high frequencies. The wide range of the observed impedance was able to be measured owing to its use of the voltage stimulation instead of the current stimulation (which is most common for EIT). The image reconstruction problem was solved using an iterative Gauss–Newton algorithm and the EIDORS (Electrical Impedance Tomography and Diffuse Optical Tomography Reconstruction Software) package. The obtained results showed a satisfactory ability to localize an insufficiently dried part of the material. Prospective ways to improve the imaging quality are also discussed.

scholarly journals Kalman Algorithm Based Electrical Impedance Tomography Imaging

2019 ◽  
Vol 4 (4) ◽  
pp. 52-55
Author(s):  
Md Rabiul Islam
Keyword(s):  
Electrical Impedance Tomography ◽  
Electrical Impedance ◽  
Signal To Noise Ratio ◽  
Spatial Location ◽  
Element Model ◽  
Target Object ◽  
Dielectric Constants ◽  
The Body ◽  
Impedance Tomography ◽  
Ac Current

Electrical Impedance Tomography (EIT) is a non-invasive imaging technique that displays changes in conductivity within a body. This method finds application in biomedical and geology. EIT finds use in medical applications, as the different tissues of the body have different conductivity and dielectric constants. In this paper a phantom model is designed considering Finite Element Model (FEM). AC current of amplitude 1 mA and frequency 1 KHz is applied considering adjacent protocol with noise less and noisy cases. From the computed voltage data image is reconstructed using Kalman algorithm. For noisy case noise levels equal to Signal-to-Noise Ratio (SNR) 30 dB, 15 dB and 7 dB were considered. Kalman algorithm is studied for EIT image reconstruction in noise free and noisy case, in terms of shape, size, spatial location of the target object.

scholarly journals Designing a bench for testing medically and technically an information and measuring system for multi-frequency electrical impedance tomography of human lungs

2021 ◽  
Vol 4 (5(112)) ◽  
pp. 27-40
Author(s):  
Grayr Aleksanyan
Keyword(s):  
Electrical Impedance Tomography ◽  
Electrical Impedance ◽  
Experimental Studies ◽  
Measuring System ◽  
Dynamic Visualization ◽  
Impedance Tomography ◽  
Written Information ◽  
Human Lungs ◽  
Wide Range ◽  
Conducting Research

This paper solves the problem of developing and creating multifunctional tools for conducting research into systems of multi-frequency electrical impedance tomography of human lungs. A test bench consisting of modern medical equipment, simulating pre-and postoperative environments to create conditions that are most similar to clinical ones, under which it is planned to operate multi-frequency electrical impedance tomography systems, was proposed and manufactured. This makes it possible to reduce significantly the time for approbation, testing, and elimination of practical inaccuracies and problems of clinical application of the developed medical and technical facilities. A positive result is achieved due to the possibility of forming new test plans with specified conditions and different levels of complexity. This enables enhancing the effectiveness of subsequent clinical tests on patients who are treated in a resuscitation unit or an intensive care unit. The operability of the bench is proved by the repeatability of obtained results of monitoring ventilation and perfusion for each examined person, the continuity of dynamic visualization of the breathing process, as well as a high degree of correlation of obtained values of differences of potentials with the readings of a bedside monitor of a patient. An information and measuring system of multi-frequency electric impedance tomography of human lungs, developed by the author earlier, was used as the EIT device. The EIT tests were performed for the frequency range of 50 kHz – 400 kHz at a current of 5 mA. All experimental studies involved volunteers who gave written information consent to participate in the tests. The results of the research show that the proposed bench can be used in practice to solve a wide range of scientific and applied problems in the field of electrical impedance tomography

scholarly journals Experimental dependences of measurement data on the volume of inhaled air in multi-frequency electrical impedance tomography

2021 ◽  
Vol 5 (5 (113)) ◽  
pp. 39-50
Author(s):  
Grayr Aleksanyan
Keyword(s):  
Electrical Impedance ◽  
Human Lung ◽  
Artificial Ventilation ◽  
Experimental Studies ◽  
Measurement Data ◽  
Healthy Person ◽  
External Respiration ◽  
Impedance Tomography ◽  
Human Lungs ◽  
Respiration Function

This paper proposes an approach to modeling the process of artificial ventilation of human lungs by their controlled filling with a fixed volume of air, using an incentive spirometer Coach 2. This makes it possible to simulate the ventilation process for a healthy person and to link the assigned respiratory volume to measurement data. The results of experimental studies of the developed system of multifrequency electric impedance tomography are presented. The tests were performed for the frequency range from 50 kHz to 400 kHz (with a pitch of 50 kHz) at assigned respiratory volumes from 500 ml to 4,000 ml (with a pitch of 500 ml) for five inhalation/exhalation cycles. The scheme of research: active inhalation ‒ passive exhalation, the number of tested volunteers ‒ 3 people from the developers of the system. As a result, the dependences of the measured values of changes in potentials on the frequency of injected current for different respiratory volumes in three test participants without pathologies of the respiratory function and the external respiration function were obtained. The obtained results of the experimental studies show that there is a dependence of the value of the measurement data both on the volume of inhaled air and on the frequency of the injected current. This feature can be used to develop a number of medical devices for personalized monitoring of human lung function. It was also revealed that there are frequencies at which the maximum spread of measurement data according to the results of a series of repeated experiments is observed. At the same time, the nature of the change in the measurement data of the EIT at an increase in the volume of inhaled air is the same for all test participants. It is assumed that this feature can also be used to increase the EIT personalization degree

CALIBRATION OF A LOW COST ELECTRICAL IMPEDANCE TOMOGRAPHY SYSTEM WITH A RING OF RESISTORS AND A KCL SOLUTION

2019 ◽  
Author(s):  
Bruno Furtado de Moura ◽  
francisco sepulveda ◽  
Jorge Luis Jorge Acevedo ◽  
Wellington Betencurte da Silva ◽  
Rogerio Ramos ◽  
...  
Keyword(s):  
Electrical Impedance Tomography ◽  
Electrical Impedance ◽  
Low Cost ◽  
Impedance Tomography ◽  
Tomography System

Arthrophytum scoparium Extract Improves Memory Impairment and Affects Acetylcholinesterase Activity In Mice Brain

2020 ◽  
Vol 21 (6) ◽  
pp. 480-487
Author(s):  
Med A. Smach ◽  
Jawhar Hafsa ◽  
Bassem Charfeddine ◽  
Hedi Dridi ◽  
Khalifa Limem ◽  
...  
Keyword(s):  
Antioxidant Activities ◽  
Saline Water ◽  
Experimental Studies ◽  
Chronic Administration ◽  
Acetylcholinesterase Activity ◽  
Control Group ◽  
Pharmacological Activities ◽  
Oxidative Damages ◽  
Y Maze ◽  
Mice Brain

Background: Arthrophytum scoparium (Pomel) Iljin (Amaranthaceae family) has been widely used in traditional Tunisian medicine to treat many disorders such as migraine, headache, and neurological disorders. This study investigates the effect of Arthrophytum scoparium Aqueous Extract (ASAE) on cognitive impairments and oxidative injury induced by galactose (10%) in a mouse model. Materials and Methods: The mice were divided randomly into 4 experimental groups, including the control group (saline water 9 ‰), Galactose group, Scop group (300 mg/kg/d), and Scop+Gal group (300 mg/kg/d). Mice received the corresponding solutions by intraperitoneal injection (i.p.) for 7 days before the Y-maze active tests. Galactose 10% was given to all groups except control and Scop groups, 30 min before the trial. Levels of Acetylcholinesterase Activity (AChE), Ascorbic Acid (AA), Gluthatione (GSH) and Malondialdehyde (MDA) in mice brains were examined. Results: Chronic administration of galactose significantly impaired cognitive performance in Y maze, caused marked oxidative damages and a significant increase in the acetylcholinesterase activity as compared to other groups. On the contrary, ASAE (300 mg/kg) treatment suppressed galactoseinduced oxidative damage by ameliorating the increased levels of GSH and AA. Moreover, ASAE treatment reduced brain AChE activities in the galactose-induced model. Conclusion: These findings suggest that ASAE exerts potent anti-amnesic effects via the modulation of cholinergic and antioxidant activities. The observed pharmacological activities should be further evaluated by detailed experimental studies and validated by clinical trials.

Reconstruction of three-dimensional data for electrical impedance tomography

1992 ◽  
Vol 28 (11) ◽  
pp. 974-976 ◽  
Author(s):  
R. Gadd ◽  
F. Vinther ◽  
P.M. Record ◽  
P. Rolfe
Keyword(s):  
Electrical Impedance Tomography ◽  
Electrical Impedance ◽  
Three Dimensional ◽  
Impedance Tomography
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