A theoretical model for the frequency-dependent dielectric properties of corneal tissue at microwave frequencies

Abstract

This paper presents a structured model of the dielectric properties of the corneal tissue at microwave frequencies, based on the fine structure and chemical composition of its constituents. This is accomplished by appropriately combining the known properties of tissue substructures using mixing rules, in order to obtain the effective macroscopic properties of the medium. The presented approach is multi-scale: it begins from the microscopic scale and derives the macroscopic properties after several scale-steps. The predictions of the model agree with the existing measured data in the literature. Verification and analysis of the model sensitivity to input parameters have been presented. The model is expected to find application in non-invasive medical sensing where it can relate dielectric response to pathological structural changes in the tissue. The model is also useful for the prediction of dielectric properties for high- frequency computational dosimetry, and for understanding the physical mechanisms behind the macroscopic dielectric behaviour in general.