Bioelectrical Impedance Methods for Noninvasive Health Monitoring: A Review.
17 Jun 2014-Vol. 2014, pp 381251-381251
TL;DR: The working principles, applications, merits, and demerits of these methods has been discussed in detail along with their other technical issues followed by present status and future trends.
Abstract: Under the alternating electrical excitation, biological tissues produce a complex electrical impedance which depends on tissue composition, structures, health status, and applied signal frequency, and hence the bioelectrical impedance methods can be utilized for noninvasive tissue characterization. As the impedance responses of these tissue parameters vary with frequencies of the applied signal, the impedance analysis conducted over a wide frequency band provides more information about the tissue interiors which help us to better understand the biological tissues anatomy, physiology, and pathology. Over past few decades, a number of impedance based noninvasive tissue characterization techniques such as bioelectrical impedance analysis (BIA), electrical impedance spectroscopy (EIS), electrical impedance plethysmography (IPG), impedance cardiography (ICG), and electrical impedance tomography (EIT) have been proposed and a lot of research works have been conducted on these methods for noninvasive tissue characterization and disease diagnosis. In this paper BIA, EIS, IPG, ICG, and EIT techniques and their applications in different fields have been reviewed and technical perspective of these impedance methods has been presented. The working principles, applications, merits, and demerits of these methods has been discussed in detail along with their other technical issues followed by present status and future trends.
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TL;DR: In this article, an updated review of EIS main implementations and applications is presented, as well as a broad range of applications as a quick and easily automated technique to characterize solid, liquid, semiliquid, organic as well and inorganic materials.
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Cites background from "Bioelectrical Impedance Methods for..."
...Fat tissues are characterized by low electrical conductivity (i.e., high impedance values) while lean tissues present high electrical conductivity (i.e., low impedance values) due to the high content of electrolytes (Kanti Bera, 2014)....
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TL;DR: The basis and fundamentals of bioimpedance measurements are described covering issues ranging from the hardware diagrams to the configurations and designs of the electrodes and from the mathematical models that describe the frequency behavior of the bioimpingance to the sources of noise and artifacts.
Abstract: This work develops a thorough review of bioimpedance systems for healthcare applications. The basis and fundamentals of bioimpedance measurements are described covering issues ranging from the hardware diagrams to the configurations and designs of the electrodes and from the mathematical models that describe the frequency behavior of the bioimpedance to the sources of noise and artifacts. Bioimpedance applications such as body composition assessment, impedance cardiography (ICG), transthoracic impedance pneumography, electrical impedance tomography (EIT), and skin conductance are described and analyzed. A breakdown of recent advances and future challenges of bioimpedance is also performed, addressing topics such as transducers for biosensors and Lab-on-Chip technology, measurements in implantable systems, characterization of new parameters and substances, and novel bioimpedance applications.
87 citations
References
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TL;DR: In this article, the electrical impedance spectroscopy (EIS) device is used for the measurement of internal moisture gradients in wood, which consists of a hand-held probe connected to a control unit interfaced with a portable personal computer and a power unit.
Abstract: A prototype of the electrical impedance spectroscopy (EIS) device for the measurement of internal moisture gradients in wood was developed. The EIS device consists of a hand-held probe connected to a control unit interfaced with a portable personal computer and a power unit. In the measurement, parallel flat electrodes of the measuring probe are laid against the wood specimen and the sine wave excitation is applied in the frequency range 1–100 kHz. The measured amplitude and phase spectral data were analyzed using the model based on constant phase elements. A spectral analysis software package was designed for measurement of subsurface transverse moisture gradients. The EIS device was tested with many types of uniform, desorption, and absorption gradients in lumber, pulpwood, and log specimens from spruce, pine, and birch. The EIS device can be easily transferred in a small case allowing field measurements.
58 citations
"Bioelectrical Impedance Methods for..." refers methods in this paper
...Therefore the EIS has been suitably applied in several fields such as electrochemistry and chemical engineering [54, 56–61], material engineering [62–71], biomedical engineering [72–76], civil engineering [77–79], wood science [80, 81], plant physiology [82–84], microfluidics [85, 86], material engineering [87–90], fuel cell technology [91], andMEMS and thin films [92, 93] and so on....
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TL;DR: In this paper, a prototype landmine detector, based on electrical impedancetomography (EIT), which can operate under realistic environmental conditions, has been developed, which is especially suited for wet lands and underwater, where other mine detectors perform poorly.
Abstract: A prototype confirmation landmine detector, based on electrical impedancetomography (EIT), which can operate under realistic environmental conditions, has been developed. Laboratory and field experiments demonstrated that it is possible to reliably reconstruct, on the scale of the electrode spacing (ES) (in width and depth), conductivity perturbations due to a shallow buried antitank mine or a similar object in a variety of soils (black earth, clay, sand) down to depths equal to the dimensions of the object (1-1.5 ES, equivalent to 14-21 cm for a 64-electrode 1 m times 1 m array). These represent the first EIT images of real landmines computed from measured data. Occasional problems were encountered with the electrical contact in very dry soils, with excessive insertion pressure being required for reliable electrode contact. However, poor contacts could be detected, and the offending probe was either reinserted or compensation was applied. A matched filter detection algorithm based on a replica of the object of interest was developed and shown to effectively reduce the false alarm rate of the detector. EIT is especially suited for wet lands and underwater, where other mine detectors perform poorly. Experiments in a water-and sediment-filled tank have demonstrated that detection of minelike objects in such an environment with a submerged array is feasible. These experiments represent the first EIT measurements of targets using an electrode array submerged underwater. EIT may also have an application in locating intact mines in the berms formed by mine-clearing equipment. The EIT sensor head could be made cheaply enough to be disposable and remotely inserted to improve safety
56 citations
"Bioelectrical Impedance Methods for..." refers methods in this paper
...EIT has been applied in a number of research areas such as medical imaging clinical diagnosis [146–152], chemical engineering [153], industrial process application [154, 155], material engineering [156], microbiology and biotechnology [157, 158], nondestructive testing (NDT) in manufacturing technology [159], civil engineering [160], earth science and geophysics and geoscience [161], defense fields [162], archaeology [163], oceanography [164], environmental engineering [165], and other fields of applied science, engineering and technologies [166]....
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TL;DR: An ethnic-specific equation for overweight women is proposed, and cross-validation of this equation indicates that it provides a reasonable estimate of body composition in overweight women.
Abstract: Bioelectrical impedance analysis to assess body composition in obese adult women: The effect of ethnicity
56 citations
TL;DR: Dedicated breast computed tomography (DBCT) is a burgeoning technology that has many advantages over current breast-imaging systems, including three-dimensional visualization of the breast that mitigates the limiting effects of superimposition noted with mammography.
56 citations
TL;DR: Two bioelectrical impedance analysis models are compared, the right-sided tetrapolar method and an experimental cylindrical method, to total body water determined by isotopic dilution in 37 prepubertal children, who were divided into development and cross-validation groups.
Abstract: SummaryWe compared two bioelectrical impedance analysis models, the right-sided tetrapolar method and an experimental cylindrical method, to total body water (TBW) determined by isotopic dilution in 37 prepubertal children aged 5–9 years, who were divided into development and cross-validation groups. Despite its theoretical advantage, no improvement in predicted TBW was seen with the experimental method. The best predictive equation, using the tetrapolar method, was TBW (kg) = 1·84 + 0·45 (height squared/resistance) + 0·11(weight); r2 = 0·98; SEE = 0·62 kg.
55 citations
"Bioelectrical Impedance Methods for..." refers background in this paper
...ECW can be found related to extracellular mass (ECM) and ICW to body cell mass (BCM)....
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...Thus by applying the alternating current at a particular frequency, BIA procedure can assess the amount of extracellular water (ECW), intracellular water (ICW), and total body water (TBW = ECW + ICW)....
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...The schematic diagram of the body composition such as fat-free mass (FFM), total body water (TBW), intracellular water (ICW), extracellular water (ECW), and body cell mass (BCM) is shown in the Figure 5....
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...ICW are found within the cells and tissues and give cell volume and tissue volumes whereas the ECW is composed of blood, lymph, and so forth [43]....
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...The equation for SFBIA and DFBIA is shown in (5a), (5b), (5c), and (6): TBW (Liters) = [ (0.3963 × height2) impedance (50 kHz) ] + (0.143 × weight) + 8.4, (6) ECW (Liters) = [ (0.178458 × height2) impedance (5 kHz) ] + (0.06895 × weight) + 3.794, (7a) TBW (Liters) = [ (0.24517 × height2) impedance (200 kHz) ] + (0.18782 × weight) + 8.197....
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