Institute of Biomedical Technologies, Auckland University of Technology, Auckland 1010, New Zealand.
Biosensors (Basel). 2023 Oct 29;13(11):961. doi: 10.3390/bios13110961.
This work aims to describe the dielectric behaviors of four main tissues in the human forearm using mathematical modelling, including fat, muscle, blood and bone. Multi-frequency bioimpedance analysis (MF-BIA) was initially performed using the finite element method (FEM) with a 3D forearm model to estimate impedance spectra from 10 kHz to 1 MHz, followed by a pilot study involving two healthy subjects to characterize the response of actual forearm tissues from 1 kHz to 349 kHz. Both the simulation and experimental results were fitted to a single-dispersion Cole model (SDCM) and a multi-dispersion Cole model (MDCM) to determine the Cole parameters for each tissue. Cole-type responses of both simulated and actual human forearms were observed. A paired -test based on the root mean squared error (RMSE) values indicated that both Cole models performed comparably in fitting both simulated and measured bioimpedance data. However, MDCM exhibited higher accuracy, with a correlation coefficient (R) of 0.99 and 0.89, RMSE of 0.22 Ω and 0.56 Ω, mean difference (mean ± standard deviation) of 0.00 ± 0.23 Ω and -0.28 ± 0.23 Ω, and mean absolute error (MAE) of 0.0007 Ω and 0.2789 Ω for the real part and imaginary part of impedance, respectively. Determining the electrical response of multi-tissues can be helpful in developing physiological monitoring of an organ or a section of the human body through MF-BIA and hemodynamic monitoring by filtering out the impedance contributions from the surrounding tissues to blood-flow-induced impedance variations.
本工作旨在使用数学建模描述人体前臂的四种主要组织（脂肪、肌肉、血液和骨骼）的介电特性。首先使用有限元法（FEM）对 3D 前臂模型进行多频生物阻抗分析（MF-BIA），以从 10 kHz 到 1 MHz 估算阻抗谱，然后进行一项初步研究，涉及两名健康受试者，以从 1 kHz 到 349 kHz 表征实际前臂组织的响应。仿真和实验结果都被拟合到单个弥散 Cole 模型（SDCM）和多个弥散 Cole 模型（MDCM）中，以确定每个组织的 Cole 参数。观察到模拟和实际人体前臂的 Cole 型响应。基于均方根误差（RMSE）值的配对检验表明，Cole 模型在拟合模拟和测量的生物阻抗数据方面表现相当。然而，MDCM 表现出更高的准确性，相关系数（R）分别为 0.99 和 0.89，RMSE 分别为 0.22 Ω 和 0.56 Ω，均值差异（平均值±标准偏差）分别为 0.00 ± 0.23 Ω 和-0.28 ± 0.23 Ω，平均绝对误差（MAE）分别为 0.0007 Ω 和 0.2789 Ω，用于阻抗的实部和虚部。确定多组织的电响应可以通过 MF-BIA 对器官或人体某一部分进行生理监测，以及通过滤除周围组织对血流引起的阻抗变化的阻抗贡献来进行血液动力学监测，从而有所帮助。
