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ABSTRACT Spirometry is a test for the diagnosis of chronic obstructive pulmonary disease. It is a technique that can be intolerant due to the essential use of a mouthpiece and a clamp. This study proposes the use of electrical impedance tomogra phy to measure respiratory parameters. Patients underwent spirometry and three respiratory exercises. The imped ance signals were convolved, and the resultant was analyzed by fast Fourier transform. The frequency spectrum was divided into seven segments (R1 to R7). Each segment was represented in terms of quartiles (Q25%, Q50%, Q75%). Each quartile of each segment was correlated with the spirometric parameters to obtain a fitting equation. FVC was correlated 70% with the 3 quartiles of R7, 3 equations were obtained with a fit of 60%. FEV1 correlated 70% with the Q50% of R7, obtaining an equation with a fit of 40%. FEV1/FVC correlated 69% with Q75% of R2, obtaining an equation with a fit of 60%. Spirometric parameters can be estimated from the implied carrier frequency components of the ventilatory impedance signal.
RESUMEN La espirometría es una prueba para el diagnóstico de enfermedad pulmonar obstructiva crónica. Es una técnica que puede resultar intolerante debido al uso imprescindible de una boquilla y una de pinza. Este estudio propone el uso de la tomografía de impedancia eléctrica para medir los parámetros respiratorios. Los pacientes realizaron una espi rometría y tres ejercicios respiratorios. Las señales de impedancia fueron convolucionadas, y la resultante se analizó mediante una transformada rápida de Fourier. El espectro en frecuencias se dividió en siete segmentos (R1 a R7). Cada segmento se representó en términos de cuartiles (Q25%, Q50%, Q75%). Cada cuartil de cada segmento se co rrelacionó con los parámetros espirométricos para obtener una ecuación de ajuste. La FVC se correlacionó en un 70% con los 3 cuartiles de R7, se obtuvieron 3 ecuaciones con un ajuste del 60%. El FEV1 se correlacionó en un 70% con el Q50% de R7, obteniéndose una ecuación con un ajuste del 40%. El FEV1/FVC se correlacionó en un 69% con el Q75% de R2, obteniéndose una ecuación con un ajuste del 60%. Los parámetros espirométricos pueden ser estimados a partir de los componentes de frecuencia portadora implícitos de la señal de impedancia ventilatoria.
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Objective:To investigate the relationship between double-triggering and abnormal movement of air in the lungs (pendelluft phenomenon) under pressure support ventilation (PSV).Methods:A prospective observational study was conducted, postoperative patients admitted to department of critical care medicine of Beijing Tiantan Hospital, Capital Medical University from April 1, 2019 to August 31, 2020 and received invasive mechanical ventilation with PSV mode were enrolled. Electrical impedance tomography (EIT) monitoring was performed. Airway pressure-time, flow-time, global and regional impedance-time curves were synchronously collected and analyzed offline. The volume of abnormal movement of air in the lungs at the beginning of inspiration was measured and defined as pendelluft volume. Double-triggered breaths were identified by trained researchers. Pendelluft volume during double-triggering was measured including the first triggered breath, the double-triggered breath, and the breath immediately following the double-triggered breath. Pendelluft volume was also measured for normal breath during the study. According to the frequency of double-triggering, patients were divided into severe (≥1 time/min) and non-severe double-triggering group. Pendelluft volume, parameters of respiratory mechanics, and clinical outcomes between the two groups were compared.Results:In 40 enrolled patients, a total of 9 711 breaths [(243±63) breaths/patient] were collected and analyzed, among which 222 breaths (2.3%) were identified as double-triggering. The Kappa of interobserver reliability to detect double-triggering was 0.964 [95% confidence interval (95% CI) was 0.946-0.982]. In 222 double-triggered breaths, pendelluft volume could not be measured in 7 breaths (3.2%), but the pendelluft phenomenon did exist as shown by opposite regional impedance change at the beginning of double-triggered inspiration. Finally, pendelluft volume was measured in 215 double-triggered breaths. Meanwhile, 400 normal breaths (10 normal breaths randomly selected for each patient) were identified as control. Compared with normal breath, pendelluft volume significantly increased in the first breath, the double-triggered breath, and the following normal breath [mL: 3.0 (1.4, 6.4), 8.3 (3.6, 13.2), 4.3 (1.9, 9.1) vs. 1.4 (0.7, 2.8), all P < 0.05]. Patients in severe double-triggering, pendelluft volume of normal breath and double-triggered breath were significantly higher than those in non-severe double-triggering group [mL: 1.8 (0.9, 3.2) vs. 1.1 (0.5, 2.1), P < 0.001; 8.5 (3.9, 13.4) vs. 2.0 (0.6, 9.1), P = 0.008]. Patients in severe double-triggering group had significantly higher respiratory rate than that in the non-severe double-triggering group (breaths/min: 20.9±3.5 vs. 15.2±3.7, P < 0.001). There were no significant differences in other respiratory mechanics parameters and main clinical outcomes between the two groups. Conclusions:During PSV, the abnormal movement of air in the lungs (pendelluft phenomenon) was more likely to occur in double-triggering especially in double-triggered breath. The more frequent the double-triggering occurred, the more serious the pendelluft phenomenon was. A higher pendelluft volume of normal breath and a higher respiratory rate were related to severity of double-triggering.
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This study aims to propose a multifrequency time-difference algorithm using spectral constraints. Based on the knowledge of tissue spectrum in the imaging domain, the fraction model was used in conjunction with the finite element method (FEM) to approximate a conductivity distribution. Then a frequency independent parameter (volume or area fraction change) was reconstructed which made it possible to simultaneously employ multifrequency time-difference boundary voltage data and then reduce the degrees of freedom of the reconstruction problem. Furthermore, this will alleviate the illness of the EIT inverse problem and lead to a better reconstruction result. The numerical validation results suggested that the proposed time-difference fraction reconstruction algorithm behaved better than traditional damped least squares algorithm (DLS) especially in the noise suppression capability. Moreover, under the condition of low signal-to-noise ratio, the proposed algorithm had a more obvious advantage in reconstructions of targets shape and position. This algorithm provides an efficient way to simultaneously utilize multifrequency measurement data for time-difference EIT, and leads to a more accurate reconstruction result. It may show us a new direction for the development of time-difference EIT algorithms in the case that the tissue spectrums are known.
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Weaning?failure?from?mechanical?ventilation?is?an?important?clinical?problem,?the?traditional?methods?of?assessing?whether?patients?can?be?weaned?from?mechanical?ventilation?or?not?cannot?meet?the?clinical?needs.?Finding?more?effective?weaning?indicators?to?determine?the?optimal?timing?of?weaning?has?important?clinical?value?for?improving?the?outcome?of?weaning?and?reducing?the?mortality?of?patients.?As?a?new?method?of?assessing?respiratory?function?of?patients,?electrical?impedance?tomography?(EIT)?is?gradually?applied?to?the?clinic,?and?its?guided?assessment?of?respiratory?function?may?open?a?new?way?for?directing?successful?weaning.?This?article?reviews?the?progress?of?EIT?in?ventilation?weaning,?in?order?to?provide?a?new?judgment?method?and?theoretical?basis?for?the?successful?weaning.
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Objective • To find out the optimal positive end expiratory pressure (PEEP) by electrical impedance tomography (EIT) for better lung recruitment and ventilation distribution in patients undergoing off pump coronary artery bypass grafting surgery (OPCAB). Methods • 105 patients underwent OPCAB from Jan. 2017 to Dec. 2017 were analysed. Patients were randomly divided into two groups, i.e. experiment group (54 cases) and control group (51 cases). Four regions of interest (ROI) were recorded by EIT. PEEP were 3 cmH2O in control group while PEEP were increased stepwise by 2 cmH2O from 0 cmH2O to 14 cmH2O in experiment group. The optimal PEEP for lung recruitment was applied in experiment group. Postoperative oxygenation index (PaO2/FiO2) and pulmonary complication were compared between two groups. Results • The overall mortality was 2 (1.90%). The incidence of postoperative pulmonary complication, pulmonary infection, atelectasis, pleural effusion were 18.10%, 2.86%, 18.10%, 18.10%, respectively. The optimal PEEP zone was 6-9 cmH2O. PaO2/FiO2 was significantly increased with the optimal PEEP in experiment group (P=0.00). There were significant differences in postoperative pulmonary complication between two groups (P=0.02). Conclusion • EIT can directly monitor ventilation distribution and titrate suitable PEEP for better lung recruitment in patients undergoing OPCAB. It can significantly reduce postoperative pulmonary complication, improve oxygenation, and decrease ICU stay and ventilation duration.
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Objective To establish a human-head phantom with realistic skull anatomy and resistivity distribution in order to provide an accurate experimental platform for brain electrical impedance tomography(EIT).Methods Firstly a skull model with 3-layer structure was constructed with double-nozzle 3D printer,and every layer had its specific resistivity verified on the accuracy. Then brain parenchyma with its resistivity was modelled using 3D printer and cerebrospinal fluid and scalp were mimicked using NaCl solution;after the whole phantom was assembled,imaging test using EIT was performed.Results The skull model was similar to the realistic one in terms of anatomy and resistivity distribution;the EIT experiment on the new phantom showed similar results to simulation.Conclusion The proposed phantom has realistic skull anatomy,resistivity distribution and multi-layer anatomical structure, which reflects the features of skull resistivity and thus is suitable for experiments on brain EIT.
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Objective To evaluate the effect of damped least-square algorithm on the identification of focal bidirectional electrical impedance perturbation in the intracranial area, and to analyze the influence of this kind of perturbation on the reconstruction quality of electrical impedance tomography. Methods Focal bidirectional electrical impedance perturbation was built based on the three-dimensional model and damped least-square algorithm was introduced into imaging. The position error and resolution were used to evaluate the imaging performance.Results When the focal electrical impedance perturbation existed,the target whose conductivity varied greatly or volume was large was more likely to be identified in the images while the target with smaller volume or variable conductivity presented in the reconstruction image was not obvious. It's pointed out that it may cause reconstruction images in some cases could not truly reflect the location and change information of the object of primary cerebral hemorrhage.At the same time,it affected the reconstruction precision,causing the position error and resolution with large fluctuation. Conclusion In reconstruction algorithm linearity correct matrix introduced for bidirectional electrical impedance perturbation contributes to enhancing the recognition of bidirectional perturbation, so that the characterization of the electrical impedance imaging can be augmented for clinical intracerebral hemorrhage.
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Objective To monitor and compare the effects of body position on the regional lung volume and FEV1/FVC with electrical impedance tomography(EIT).Methods Twelve healthy young subjects[(26.6±2.5)yr]were detected by EIT during FVC maneuver in 3 body positions (sitting,supine and prone).Functional EIT images of FVC and FEV1/FVC were obtained;the proportion of regional ventilation volume and the mean of regional FEV1/FVC were calculated.Results The ventral and dorsal proportion of ventilation volume was 37.65% : 62.35% in sitting position and 37.59% : 62.41% in supine position, respectively.While in the prone position,the value was 48.56%:51.44%,which was close to 1:1.The mean of regional FEV1/FVC in the dependent lung region was 0.84 in supine position and 0.81 in prone position,while in sitting position,the corresponding value was 0.90 and 0.94, respectively. Conclusion The results shows that the ventilation transfers to the gravity dependent region obviously, while the flow rate decreases. The result provides direct evidences for mechanical ventilation patients using prone position to improve oxygenation,as well as a research foundation for EIT monitoring regional lung ventilation in the clinical setting.
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Objective·To find out the optimal positive end expiratory pressure (PEEP) by electrical impedance tomography (EIT) for better lung recruitment and ventilation distribution in patients undergoing off pump coronary artery bypass grafting surgery (OPCAB). Methods?·?105 patients underwent OPCAB from Jan. 2017 to Dec. 2017 were analysed. Patients were randomly divided into two groups, i.e. experiment group (54 cases) and control group (51 cases). Four regions of interest (ROI) were recorded by EIT. PEEP were 3?cmH2O in control group while PEEP were increased stepwise by 2?cmH2O from 0?cmH2O to 14?cmH2O in experiment group. The optimal PEEP for lung recruitment was applied in experiment group. Postoperative oxygenation index (PaO2/FiO2) and pulmonary complication were compared between two groups. Results?·?The overall mortality was 2 (1.90%). The incidence of postoperative pulmonary complication, pulmonary infection, atelectasis, pleural effusion were 18.10%, 2.86%, 18.10%, 18.10%, respectively. The optimal PEEP zone was 6-9?cmH2O. PaO2/FiO2was significantly increased with the optimal PEEP in experiment group (P=0.00). There were significant differences in postoperative pulmonary complication between two groups (P=0.02). Conclusion?·?EIT can directly monitor ventilation distribution and titrate suitable PEEP for better lung recruitment in patients undergoing OPCAB. It can significantly reduce postoperative pulmonary complication, improve oxygenation, and decrease ICU stay and ventilation duration.
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The inverse problem of electrical impedance tomography (EIT) is seriously ill-posed, which restricts the clinical application of EIT. Regularization is an important numerical method to improve the stability of the EIT inverse problem as well as the resolution of the imaging. This paper proposes a self-diagnosis regularization method based on Tikhonov regularization and diagonal weight regularization method (DWRM). Firstly, the ill-posedness of the inverse problem is analyzed by sensitivity. Then, the performance of the self-diagnosis regularization is analyzed through the singular value theory. Finally, some simulated experiments including simulations and flume experiment are carried out and verify that the self-diagnosis regularization has better image quality and anti-noise ability than those of traditional regularization methods. The self-diagnosis regularization method weakens the ill-posedness of inverse problem of EIT and can prompt the practical application of EIT.
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RESUMEN: En este trabajo se presenta un método para medir densidad ósea. El método consiste en la medición de conductividad eléctrica de material óseo por medio de Tomografía de Impedancia Eléctrica (TIE). Se hace uso de una celda de prueba con valores simulados de hueso aplicando corrientes y registrando voltajes, para después usar una reconstrucción por retroproyección y generar mapas de conductividad por medio de gráficas. Los datos obtenidos son analizados y a partir de ellos se obtiene una distribución de la medida de conductividad eléctrica del material óseo, que varía dependiendo del grado de porosidad que presenta en cada región. La ventaja de utilizar el método de tomografía de impedancia es que permite medir la conductividad efectiva del hueso porque se mide en todas las direcciones. Por lo tanto es posible determinar porosidad en material óseo usando mediciones de conductividad eléctrica por medio del método TIE propuesto, lo cual permite calcular un valor numérico de densidad ósea.
ABSTRACT: In this paper a method to measure bone density was developed. The method consists in the measurement of electrical conductivity of bone by Electrical Impedance Tomography (EIT). A phantom with simulated data of bone is used, applying currents and recording voltages; then a backprojection reconstruction is used to generate maps with graphic conductivity values. The data obtained were analyzed and was obtained a distribution of electrical conduc tivity of bone, wich varies according to the bone porosity level in each region. A significant advantage of using this method is that is possible to measure electrical conductivity in several directions of the bone, obtaining an effective conductivity. Therefore it is possible to determine the porosity in the bone with measurements of electrical conductivity using the proposed EIT method, this allows to calculate a numerical value for bone density.
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Objective To put forward a method for 3D electrical impedance finite element joint modeling and simulation using COMSOL for visual modeling and Visual C++ for programming.Methods A model was established with COMSOL,and then transformed into a.stl file and introduced into Visual C++ simulation platform.Delaunay tetrahedral mesh generation algorithm was used for finite element meshing,calculation and simulation,and joint modeling and simulation were realized finally.Results Simulation result showed that the method could be used to introduce COMSOL model and complete 3D finite element simulation.Conclusion The method proves its compatibility with the models generated by multi software and practicability for joint modeling and simulation.
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Objective To put forward a method for 3D electrical impedance finite element joint modeling and simulation using COMSOL for visual modeling and Visual C++ for programming.Methods A model was established with COMSOL,and then transformed into a.stl file and introduced into Visual C++ simulation platform.Delaunay tetrahedral mesh generation algorithm was used for finite element meshing,calculation and simulation,and joint modeling and simulation were realized finally.Results Simulation result showed that the method could be used to introduce COMSOL model and complete 3D finite element simulation.Conclusion The method proves its compatibility with the models generated by multi software and practicability for joint modeling and simulation.
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Objective To improve the image quality of the electrical impedance tomography (EIT) by introducing the prior information into the regularization matrix.Methods The linear combination of the conductivity was established by background conductivity of dynamic variation,the covariance matrix was used here to remove the correlation between the background conductivity,and this prior information was introduced to construct the regularization matrix.Resnlts Compared with the traditional regularization matrix,the one involving in the prior information on the dynamic background gained more stable and better images.Conclusion Trials prove the efficacy of the regularization matrix on EIT imaging in 1 respiratory cycles (or heart beat),and following related researches may find theoretical references and support for feasibility.
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PURPOSE: To realistically map the electric fields of biological tissues using a diffusion tensor magnetic resonance electrical impedance tomography (DT-MREIT) method to estimate tissue response during electrical stimulation. METHODS: Imaging experiments were performed using chunks of bovine muscle. Two silver wire electrodes were positioned inside the muscle tissue for electrical stimulation. Electric pulses were applied with a 100-V amplitude and 100-μs width using a voltage stimulator. During electrical stimulation, we collected DT-MREIT data from a 3T magnetic resonance imaging scanner. We adopted the projected current density method to calculate the electric field. Based on the relation between the water diffusion tensor and the conductivity tensor, we computed the position-dependent scale factor using the measured magnetic flux density data. Then, a final conductivity tensor map was reconstructed using the multiplication of the water diffusion tensor and the scale factor. RESULTS: The current density images from DT-MREIT data represent the internal current flows that exist not only in the electrodes but also in surrounding regions. The reconstructed electric filed map from our anisotropic conductivity tensor with the projected current density shows coverage that is more than 2 times as wide, and higher signals in both the electrodes and surrounding tissues, than the previous isotropic method owing to the consideration of tissue anisotropy. CONCLUSIONS: An electric field map obtained by an anisotropic reconstruction method showed different patterns from the results of the previous isotropic reconstruction method. Since accurate electric field mapping is important to correctly estimate the coverage of the electrical treatment, future studies should include more rigorous validations of the new method through in vivo and in situ experiments.
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Anisotropy , Diffusion Tensor Imaging , Diffusion , Electric Conductivity , Electric Impedance , Electric Stimulation , Electrodes , Magnetic Resonance Imaging , Methods , Silver , WaterABSTRACT
Objective To verify the effectiveness of electrical impedance tomography (EIT) with multi-layer electrodes in gastric emptying measurement by simulation experiments using EIT with three-layer electrodes.Methods Firstly,EIT system with three-layer electrodes and gastric emptying measurement simulation equipment was designed and constructed to simulate gastric emptying process and obtain EIT reconstruction images.Secondly,the region where the electrical characteristic of gastric changes was selected as region of interest.Finally,the relative impedance change rate in region of interest for every image obtained from all three layers was consecutively recorded,then the gastric emptying curve was formed and gastric emptying time was calculated.Results There are obvious differences among the sharp of impedance change curves of interested region for three layers,and the gastric emptying time and process of each layer is also different from one another.It is suggested that the passing path and emptying manner of food in gastric emptying process reflected by EIT images varied from layer to layer.Therefore,the necessity and feasibility of using EIT with three-layer electrodes in gastric emptying measurement study is verified.Conclusions EIT with three-layer electrodes can provide more abundant information of gastric motility function associated with gastric emptying pathology and physiology state.It is likely to be a noninvasive,convenient and effective imaging method for the detection and evaluation research on gastric emptying and gastric motility.
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Objective Practical electrical impedance tomography (EIT) system with certain measurement resolution (MR) and signal-to-noise ratio (SNR) differs a lot from ideal simulation conditions in EIT methodology research. The aim of this paper was to study the impact of practical system with different MR and SNR on EIT. Methods Based on the ideal simulation boundary voltages of adjacent excitation and adjacent measurement pattern, practical systems whose MR were 0.1 mV and 0.01 mV, SNR ranged from 40-80 dB and no noises were simulated, simulation study for three imaging models A, B and C with different positions in the to-be imaged field under practical system conditions above was carried out using the combined Tikhonov-NOSER regularization algorithm, and error of reconstruction (ER) function and structure similarity (SSIM) function were adopted for quantitative evaluation of image effect. Results There are differences between images obtained under different MR and SNR for different image models. In order to obtain images for three models, SNR of system should be at least 40-50 dB when MR was 0.01 mV. For the goal to obtain high quality images of A, B and C, SNR should be 80, 70 and 60 dB respectively. When MR was 0.1 mV, SNR for obtaining images of A, B, C were 60, 50 and 40 dB. Moreover, the improvement of images with increasing SNR under MR of 0.1 mV was not as obvious as that of MR at 0.01 mV. Conclusions Blind pursuit of single high SNR is of no help to improve system performance and image reconstruction effect except increasing the difficulties in hardware design. The extremity SNR is 50-60 dB for system with MR of 0.01 mV and 60-70 dB for system with MR of 0.1 mV.
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INTRODUÇÃO: A Tomografia por Impedância Elétrica (TIE) é um método de imageamento de baixo custo, não invasivo, portátil e livre de radiacão ionizante, que é capaz de mapear a distribuicão das propriedades elétricas de tecidos biológicos. Apesar da baixa resolucão das imagens reconstruídas, quando comparadas a outras técnicas de imageamento tomográfico, tem-se observado uma série de aplicacões clínicas nas quais a EIT é utilizada para monitorar a atividade de determinados tecidos do corpo humano. A maioria dos sistemas de EIT comerciais tem sido pautada no paradigma originalmente proposto de uma configuracão multiportas. Este trabalho apresenta um algoritmo de reconstrucão de imagem para um sistema alternativo de EIT que usa uma configuracão multiterminais. MÉTODOS: O algoritmo é baseado na associacão entre o plano tomográfico do volume condutor e um sistema eletrostático análogo. Para avaliar o algoritmo, imagens de EIT foram reconstruídas a partir de dados obtidos experimentalmente em tanque com solucão salina, sendo as mesmas quantificadas por meio de métricas estabelecidas para este propósito. RESULTADOS: Quantitativamente, as imagens reconstruídas com o algoritmo proposto apresentaram um erro de posicão de ±10%, resolucão e deformacão decrescentes do centro para a borda e oscilacão em torno de 60% do meio. CONCLUSÃO: Uma vez que o algoritmo não possui nenhum processo de filtragem, os resultados foram considerados satisfatórios e encorajadores para trabalhos futuros visando melhorias.
INTRODUCTION: Electrical Impedance Tomography (EIT) is a low cost, non-invasive, portable and free of ionizing radiation method for imaging the distribution of the electric properties of biological tissues. Despite the low resolution of the reconstructed images when compared with other tomographic techniques, there is a range of clinical applications in which the EIT has been used to monitor the activity of certain body tissues. Most of commercial EIT systems are based on the original paradigm defined as a multiport configuration. This paper presents an algorithm developed to reconstruct images for an alternative multiterminal-based EIT system. METHODS: The algorithm is based on the association between the tomographic plane of the conductor volume and an analogous electrostatic system. To evaluate the algorithm, EIT images were reconstructed using data obtained experimentally in a saline solution tank, which were quantified by some metrics established for this purpose. RESULTS: Quantitatively, EIT images reconstructed by the proposed algorithm presented a position error around ±10%, resolution and shape deformation decreasing from center to the edge, and ringing around 60% of the medium. CONCLUSION: Taking into account that no filtering was used in the algorithm, the results can be considered satisfactory and encourage future works aiming further improvement.
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ObjectiveA general experiment platform of electrical impedance tomography(EIT) based on field programmable gate array(FPGA) was designed to meet the requirements of EIT digital measurement.A digital current source and the research on digital demodulation method was completed.MethodsFor construction of the experiment platform,DDS module,D/A and A/D interface module,digital demodulation module and RS-232 communication module were all integrated in one FPGA chip.ResultsThe source can provide multi-frequency excitation signals of 2 mA in the range of 6.1-390.6 kHz.The output impedance of the source was higher than 190 kΩ.Both the real and the virtual information of measured impedance could be extracted.ConclusionMeasurements based on bioimpedance-equivalent circuit model verified the validity of the platform.The research results of this paper provides a foundation for the construction of a practical EIT system.
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Objective: The Meridian Theory is an important component and the theory basis of Traditional Chinese Medicine. Three dimensional localization is the key to research of the Meridian Theory. Imaging is a scientific and practical method for the three dimensional localization of the meridian. Methods: The methods and actuality of the intrinsic quality and localization of meridians were first introduced. Then the methods and disadvantages of electrical impedance tomography (EIT) were also re-viewed. Based on these, the advantages and disadvantages of various methods applying to localization of meridian were analy-sised. Results: A new technology, magnetic detection electrical impedance tomography (MD-EIT) has obvious advantages com-paring to other EIT methods. It can fit comfortably on the dimentional localization of the meridian. Conclusions: MD-EIT can be applied not only to locate the meridians, but also to heart and lung detection and cancer diagnosis. There is a wide range of appli-cations for MD-EIT in medicine, It has great space for development.