Temperature and Frequency Dependence of Human Cerebrospinal Fluid Dielectric Parameters
Weice Wang,
Mingxu Zhu,
Benyuan Liu,
Weichen Li,
Yu Wang,
Junyao Li,
Qingdong Guo,
Fang Du,
Canhua Xu,
Xuetao Shi
Affiliations
Weice Wang
Department of Biomedical Engineering, Shaanxi Provincial Key Laboratory of Bioelectromagnetic Detection and Intelligent Perception, Air Force Medical University, Xi’an 710032, China
Mingxu Zhu
Department of Biomedical Engineering, Shaanxi Provincial Key Laboratory of Bioelectromagnetic Detection and Intelligent Perception, Air Force Medical University, Xi’an 710032, China
Benyuan Liu
Department of Biomedical Engineering, Shaanxi Provincial Key Laboratory of Bioelectromagnetic Detection and Intelligent Perception, Air Force Medical University, Xi’an 710032, China
Weichen Li
Department of Radiology, Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Air Force Medical University, Xi’an 710000, China
Yu Wang
Institute of Medical Research, Northwestern Polytechnical University, Xi’an 710072, China
Junyao Li
Department of Biomedical Engineering, Shaanxi Provincial Key Laboratory of Bioelectromagnetic Detection and Intelligent Perception, Air Force Medical University, Xi’an 710032, China
Qingdong Guo
Department of Neurosurgery, Xijing Hospital, Air Force Medical University, Xi’an 710032, China
Fang Du
Department of Neurology, Xijing Hospital, Air Force Medical University, Xi’an 710032, China
Canhua Xu
Department of Biomedical Engineering, Shaanxi Provincial Key Laboratory of Bioelectromagnetic Detection and Intelligent Perception, Air Force Medical University, Xi’an 710032, China
Xuetao Shi
Department of Biomedical Engineering, Shaanxi Provincial Key Laboratory of Bioelectromagnetic Detection and Intelligent Perception, Air Force Medical University, Xi’an 710032, China
Accurate human cerebrospinal fluid (CSF) dielectric parameters are critical for biological electromagnetic applications such as the electromagnetic field modelling of the human brain, the localization and intensity assessment of electrical generators in the brain, and electromagnetic protection. To detect brain damage signals during temperature changes by electrical impedance tomography (EIT), the change in CSF dielectric parameters with frequency (10 Hz–100 MHz) and temperature (17–39 °C) was investigated. A Debye model was first established to capture the complex impedance frequency and temperature characteristics. Furthermore, the receiver operating characteristic (ROC) analysis based on the dielectric parameters of normal and diseased CSF was carried out to identify lesions. The Debye model’s characteristic fc parameters linearly increased with increasing temperature (R2 = 0.989), and R0 and R1 linearly decreased (R2 = 0.990). The final established formula can calculate the complex impedivity of CSF with a maximum fitting error of 3.79%. Furthermore, the ROC based on the real part of impedivity at 10 Hz and 17 °C yielded an area under the curve (AUC) of 0.898 with a specificity of 0.889 and a sensitivity of 0.944. These findings are expected to facilitate the application of electromagnetic technology, such as disease diagnosis, specific absorption rate calculation, and biosensor design.
