A dielectric inverse problem applied to human skin measurements during glucose excursions.

A fringing field capacitive sensor has been used to measure the dielectric properties of human skin and underlying tissue in the MHz frequency range. It has recently been shown in clinical experimental studies that these dielectric properties can be related to the effects of in vivo glucose variations of the test subject. Previously, the relationship between electrical impedance and the glucose level has been established via statistical methods, such as the regression method.

Characteristics of a multisensor system for non invasive glucose monitoring with external validation and prospective evaluation.

The Multisensor Glucose Monitoring System (MGMS) features non invasive sensors for dielectric characterisation of the skin and underlying tissue in a wide frequency range (1 kHz-100 MHz, 1 and 2 GHz) as well as optical characterisation. In this paper we describe the results of using an MGMS in a miniaturised housing with fully integrated sensors and battery. Six patients with Type I Diabetes Mellitus (age 44±16 y; BMI 24.

The effect of blood content on the optical and dielectric skin properties.

A wearable system incorporating sensors for dielectric and optical spectroscopy was used to study skin properties and their dependence on the cutaneous blood content (CBC). Simultaneous measurements with both modalities were carried out on the upper arm during blood perfusion-provoking exercises performed by four subjects in four separate sets of experiments. By relating changes in the attenuation of green (central wavelength λ(c) = 568 nm) and infrared (λ(c) = 798 nm) light, the ratio of mean pathlengths travelled by photons in the skin blood plexus was obtained.

Validation of human skin models in the MHz region.

The human skin consists of several layers with distinct dielectric properties. Resolving the impact of changes in dielectric parameters of skin layers and predicting them allows for non-invasive sensing in medical diagnosis. So far no complete skin and underlying tissue model is available for this purpose in the MHz range.

Non-invasive glucose monitoring in patients with Type 1 diabetes: a Multisensor system combining sensors for dielectric and optical characterisation of skin.

In vivo variations of blood glucose (BG) are affecting the biophysical characteristics (e.g. dielectric and optical) of skin and underlying tissue (SAUT) at various frequencies.