In electrical impedance tomography (EIT), it is difficult to obtain the intracranial due highly resistive skull enclosing brain. Therefore, a high-precision data acquisition system required for brain EIT. this paper, we used digital synthesis method and demodulation technique with high noise immunity eliminate random errors. Moreover, focused on two problems encountered during EIT acquisition: 1) shunt effect excitation current distributed capacitance between electrodes ground 2) common-mode...

Delayed detection of an internal hemorrhage may result in serious disabilities and possibly death for a patient. Currently, there are no portable medical imaging instruments that suitable long-term monitoring patients at risk hemorrhage. Electrical impedance tomography (EIT) has the potential to monitor continuously as novel functional image modality instantly detect occurrence However, low spatial resolution high sensitivity noise this technique have limited its application clinics. In...

Magnetic induction tomography (MIT) is an efficient solution for long-term brain disease monitoring. It focuses on reconstructing the brain's bio-impedance distribution through non-intrusive electromagnetic fields. However, high-quality reconstruction of images remains a significant challenge, as from weak and noisy signals highly non-linear ill-conditioned problem. In this work, we propose generative adversarial network (GAN) enhanced MIT technique, named MITNet, based complex convolutional...

Magnetic induction tomography (MIT) is a contactless and noninvasive technique to reconstruct the conductivity distribution in human cross-section. In this paper, we want study feasibility of imaging low-contrast perturbation small volume object brains. We construct three-layer brain physical phantom which mimics real brains by introducing an artificial skull layer. Using our MIT data acquisition system on differential algorithm, have obtained series reconstructed images objects. All objects...

Brain electrical impedance tomography (EIT) is a difficult task as brain tissues are enclosed by the skull of high resistance and cerebrospinal fluid (CSF) low resistance, which makes internal resistivity information more to extract. In order seek single source drive pattern that suitable for EIT, we built realistic experimental setting simulates head with scalp, skull, CSF brain, compared performance adjacent, cross, polar pseudo-polar patterns in terms boundary voltage dynamic range,...

Objective: Magnetic induction tomography (MIT) is viewed as a promising method for brain imaging. Most MIT studies are based on time-difference imaging, which cannot be used detecting hemorrhagic stroke. However, many years, multifrequency (mfMIT) has been proposed the early detection of stroke, but focus primarily theoretical analysis and simulations. mfMIT not applied in clinical research owing to issues such inadequate imaging algorithms systems. Methods: A weighted frequency difference...

Objective. Traditional magnetic induction tomography (MIT) algorithms have problems in reconstruction, such as large area error (AE), blurred boundaries of reconstructed targets, and considerable image noise (IN). As the size boundary a lesion greatly affect treatment plan, more accurate are necessary to meet clinical needs.Approach. In this study, adaptive threshold split Bregman (ATSB) is proposed for brain injury monitoring imaging MIT. We established 3D MIT simulation model with actual...

Current medical imaging techniques are not effective for timely detection of internal hemorrhage when the bleeding is slow and in small quantities. In this study, electrical impedance tomography (EIT) was applied to monitor intraperitoneal an animal model. Five healthy pigs three months old were used. The process simulated with injection anticoagulated blood which controlled by electronic syringe pump. injected rate no more than 100 ml h(-1) total volumes ranged from 300 500 ml. Sixteen...

Objective To investigate the possible use of electrical impedance tomography (EIT) in monitoring focal cerebral infarction a rabbit model. Methods A model was established eight New Zealand rabbits using photochemical method without craniectomy. Focal confirmed by histopathological examination. Intracranial variation measured 16 electrodes placed circle on scalp. EIT images were obtained damped least-squares reconstruction algorithm. The average resistivity value (ARV) infarct region...

To establish a high precision data acquisition system for multi-frequency electrical impedance tomography (EIT), series of methods were introduced. Those include building driving signal with up to four frequency components diminish the effect dynamic change tissues resistivity, extracting information by digital demodulator that can improve SNR 8 times. The established work at wide range from 1.6kHz 380kHz. Its CMRR is 74dB 100kHz. output current source 2MΩ frequency. And measurement on...

More than half of the stroke patients are cause by cerebral ischemia/ hypoxia, and it is no means an easy affairs to detect ischemic tissue when rescuable drug intervention using traditional imaging technique. The purpose this paper testify feasibility monitoring ischemia. By a newly developed high precision data acquisition system specially configured method, series experiments were performed on 8 Chinese local rabbits, who have been induced with cortical ischemia photochemical method. This...

Abstract As a noncontact, noninvasive medical imaging technique, magnetic induction tomography (MIT) can measure the conductivity distribution inside human body. Moreover, animal testing is crucial before performing clinical trials. An abdominal subcutaneous injection rabbit model was used to simulate two local perturbations, that is, (1) injecting 0.9% NaCl solution and (2) in vitro heparinized blood. Using an improved MIT data acquisition system record data, series of time-difference...

In electrical impedance tomography (EIT), measurements of developed surface potentials due to applied currents are used for the reconstruction conductivity distribution. Practical implementation EIT systems is known be problematic high sensitivity noise such systems, leading a poor imaging quality. present study, performance an induced current (ICEIT) system, where eddy using magnetic induction, was studied by comparing voltage simulated data, and examining quality with respect...

Magnetic Induction Tomography (MIT) of biological tissue is a contactless and noninvasive method to image the complex conductivity distribution or its changes inside human body. In this paper, 2D (two-dimensional) simulations forward problem in MIT are performed by finite element an inverse solver based on regularized Newton-Raphson developed reconstruct images from simulated measuring data. Preliminary simple head model presented. Images can be reconstructed successfully with using The...

Electrical impedance tomography (EIT) estimated the electrical conductivity distribution within a body. Bipolar drive pattern appeared in most EIT studies that current was injected with single source and sink. In present study, we built computational phantom compared quality of dynamic image terms data quality, resolution anti-noise performance associated three different bipolar patterns: polar pattern, pseudo-polar adjacent pattern. The results demonstrated is optimal.

In this study, a serial EIT data acquisition system was constructed. It is consisted by digital synthesis based programmable current source, shield guard and sink feedback electrode interface subsystem, gain amplifier voltmeter, an orthogonal sequential demodulation impedance method. The has bandwidth of 1-190 kHz with imaging speed 1 fps. can produce the driving SNR higher than 89 dB, measure voltage difference CMRR 75 dB in bandwidth. measured results on calibration model show that it high...

Skeletal muscle exhibiting complex and excellent precision has evolved for millions of years. better performance simpler structure compared with existing driving modes. Artificial may be designed by analyzing imitat

Electrical impedance scanning (EIS) is a kind of potential bio-impedance measurement technology, especially aiding the diagnosis breast cancer in women. By changing frequency driving signal turn while keeping other conditions stable, multi-frequency results on object can be obtained. According to least square method and circuit theory, parameters two models are deduced when measured with data at multiple frequencies. The arcs, real imaginary parts trans-admittance coordinate, made by...

In order to extract the impedance information at different frequencies in our multi-frequency electrical tomography (EIT) system, a digital demodulation method was employed. Theoretically, this can improve SNR by √(N/2) times, if we sampling N point per period. Moreover, as very little system resources been needed method, all calculating operations be finished single Field Programmable Gate Arrays (FPGA) device instead of personal computer. And final data acquisition based on established and...

A simulative study was performed to measure the dielectric properties of anisotropic tissue using several in vivo and vitro probes. COMSOL Multiphysics selected carry out simulation. Five traditional probes a newly designed probe were used this study. One these an measurement other five vivo. The simulations terms minimal volume for measurements, calibration constant, on isotropic tissue. Results showed that can be in-cell tissues. When measured with probes, all accurately. For measurements...