DEVICE AND METHOD FOR DETERMINING AT LEAST ONE CHARACTERIZING PARAMETER OF MULTILAYER BODY TISSUE

• US 20110160554A1
• Filed: 06/18/2008
• Published: 06/30/2011
• Est. Priority Date: 06/18/2008
• Status: Abandoned Application

• Current Assignee: Biovotion AG (Biofourmis AG)
• Original Assignee: Biovotion AG (Biofourmis AG)
• Inventors: Megej, Alexander, Caduff, Andreas, Talary, Mark
• Application Number:
  US12/999,127
• Publication Number:
  US 20110160554A1
• Time in Patent Office: Days
• US Class Current: 600/365
• CPC Class Codes: A61B 5/0507 using microwaves or terahertz waves
• CPC Class Codes: A61B 5/0537 Measuring body composition by impedance, e.g. tissue hydration or fat content
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1495 Calibrating or testing of in-vivo probes
• CPC Class Codes: A61B 5/4869 Determining body composition

Abstract

A device for the non-invasive measurement of a glucose level, body hydration or another characterizing parameter of body tissue comprises at least two coplanar waveguides arranged on a common support. An AC signal is applied to the first ends of the coplanar waveguides, and the signal arriving at the second end is measured. The coplanar waveguides have differing gap widths, such that their electric fields have different reach into the body tissue. This allows obtain depth resolved information about the permittivities of individual tissue layers and to obtain more accurate results.

Claims

1. A device for determining at least one characterizing parameter P of living body tissue, in particular a glucose level or water content, comprising

a number N>

1 of coplanar waveguides, each coplanar waveguide comprising a center strip electrode between ground electrodes, wherein at least some of said coplanar waveguides have different gap widths between their center strip electrode and their ground electrodes for generating electrical fields of different reach,

a signal generator generating at least one AC signal, wherein first ends of said coplanar waveguides are connected to said signal generator,

a measuring unit, wherein a second ends of said coplanar waveguides are connected to said measuring unit for measuring N measured parameters m_i,

a control unit for determining said characterizing parameter P from at least part of said measured parameters m_i.

2. The device of claim 1, comprising at least one coplanar waveguide having a gap width of 100 μ

m or less.

3. The device of claim 1, comprising at least one co-planar waveguide having a gap width of at least 1 mm, in particular between 1 and 4 mm.

4. The device of claim 1, comprising at least one co-planar waveguide having a gap width of at least 4 mm.

5. The device of claim 1, wherein said signal generator generates an AC signal having a frequency of at least 50 MHz.

6. The device of claim 1, wherein said ground electrodes are wider than said center strip electrodes.

7. The device of claim 1, further comprising a non-conductive cover layer covering said electrodes.

8. Use of the device of claim 1, for measuring a glucose level.

9. Use of the device of claim 1, for measuring a water content.

10. A method for determining at least one characterizing parameter P of body tissue, in particular a glucose level or water content, comprising,

applying a number N>

1 of coplanar waveguides to a skin region of said body tissue, each coplanar waveguide comprising a center strip electrode between ground electrodes, wherein at least some of said coplanar waveguides have different distances between their center strip electrode and their ground electrodes generating electrical fields of different reach by means of said coplanar waveguides by applying an AC signal to a first end of each coplanar waveguide,

measuring N measured parameters m_i depending on a signal exiting from a second end of each coplanar waveguide,

determining said characterizing parameter P from at least part of said measured parameters m_i.

11. The method of claim 10, wherein at least a first of the measured parameters m_i1 of a layer i1 depends on the characterizing parameter P as well as on a further parameter Q and at least a second of the measured parameters m_i2 of a layer i2 above said layer i1 depends on said further parameter Q and to a lesser degree on the characterizing parameter P, said method further comprising the step of

combining the measured parameters m_i1 and m_i2 for obtaining a calculated value (∈

_i1) that depends less on the further parameter Q than said measured parameter m_i1.

12. The method of claim 11, wherein said characterizing parameter P is a glucose level

13. The method of claim 12, wherein a coplanar waveguide i1 with a distance between its center strip electrode and its ground electrodes of at least 1 mm is used for measuring said measured parameter m_i1 and a coplanar waveguide i2 with a distance between its center strip electrode and its ground electrodes of less than 1 mm is used for measuring said measured parameter m_i2.

14. The method of claim 13, wherein said coplanar waveguide i1 has a distance between its center strip electrode and its ground electrodes of less than 4 mm.

15. The method of claim 11, wherein said characterizing parameter P is water content.

16. The method of claim 15, wherein a coplanar waveguide i1 with a distance between its center strip electrode and its ground electrodes of at least 4 mm is used for measuring said measured parameter m_i1 and a coplanar waveguide m_i2 with a distance between its center strip electrode and its ground electrodes of less than 5 mm is used for measuring said measured parameter m_i2.