Bioelectrical Impedance Methods for Noninvasive Health Monitoring: A Review

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.

Electrical impedance spectroscopy (EIS) for biological analysis and food characterization: a review

“…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). TBW is the major compound of FFM that helps the flow of electrical current due to the conductivity of electrolytes dissolved in body water (Khalil et al, 2014).…”

Monitoring thoracic fluid content using bioelectrical impedance spectroscopy and Cole modeling

“…the interstitial fluid in tissues, or blood plasma. When excited by an alternating electrical current, biologic tissues show a complex electrical bioimpedance that varies with tissue composition [11]; increased fluid volume causes the bioimpedance to decrease. Although the frequency of the applied current is not standardized for fluid status monitoring, it is commonly in the so-called "β-dispersion" range 5-1000 kHz.…”

“…An empirical model, known as the Cole model [13], which describes the circular arc and the frequency scale, has been widely used in order to derive electrical properties of tissue. The model parameters are associated with tissue composition, including intracellular and extracellular fluids, and tissue structure [11]. Previous studies have shown that altered tissue composition leads to changes in the impedance locus, e.g.…”

“…Bioimpedance measurements have been used in the assessment of body composition, including body fat, muscle mass and total body water [11,17], as well as in monitoring hemodialysis [18][19]. These applications rely on whole body measurements obtained using a hand-to-foot electrode configuration.…”

The effect of heart pulsatile on the measurement of artery bioimpedance

“…Furthermore, the studying of the heart pulsatile effect may be used to measure the heart rate as a novel method for heart rate detection based on bioimpedance phenomena. The heart rate measuring using bioimpedance technique will be a new addition in medical devices unlike existing devices due to the already mentioned advantages [2].…”