Method and device for monitoring analyte concentration by optical detection

• US 20050070770A1
• Filed: 12/12/2002
• Published: 03/31/2005
• Est. Priority Date: 12/17/2001
• Status: Active Grant

• Current Assignee: P&V Consulting GmbH & Co. KG
• Original Assignee: Danfoss A/S
• Inventors: Dirac, Holger, Schweitz, Kasper Oktavio
• Granted Patent: US 7,248,906 B2
• Time in Patent Office: Days
• US Class Current: 600/316
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1459 invasive, e.g. introduced into the body by a catheter A61B5/1464 takes precedence
• CPC Class Codes: G01N 21/35 using infrared light G01N21/39 takes precedence

Abstract

A method and device are provided for the determination of the concentration of compounds in body tissue. The method utilises optical methods based on the interaction of light with compounds, whereby the concentration of the compound under analysis is determined. The method is especially suited for analysis for the concentration of glucose in blood or tissue of diabetic patients, a device being implanted underneath the skin of the patient and the method being carried out by using the implanted device. The device contains photo detectors at different levels connected by wires to an electronic circuit device. A differential analysis is performed on the signals from the detectors to reduce the effect of skin on the analysis.

Claims

1-11. -11. (Canceled)

12. A device for implantation beneath the skin of a living creature, the device having outer surfaces of biocompatible material and comprising:

detection means for detection of light, the said detection means comprising at least one of;

a substantially flat area constituting a first area and a plurality of areas constituting a first group of areas, and at least one of;

a substantially flat area constituting a second area and a plurality of areas constituting a second group of areas; and

transmitting means for transmitting a signal derived from said detection means to an external device, wherein the arrangement of the first and second areas or groups of areas within the device is such that the distance, between the skin and said detection means, over which light from a light source interacts with compounds and tissue in respect of said first area or group of areas differs from the distance, between the skin and said detection means, over which light from a light source interacts with compounds and tissue in respect of said second group of areas.

13. A device according to claim 12, wherein groups of areas are provided, each group of areas forms a common level, and the common levels have a predetermined spacing from each other to provide the said difference in distance over which light interacts with compounds and tissue.

14. A device according to claim 13, wherein the first group of areas is formed at a base level of the device and the second group of areas is formed by projections from the said base level to a top level.

15. A device according to claim 12, further including a spacer, covering one of said at least one areas or groups so that compounds and tissue are unable to fill the volume of the spacer, the spacer providing the difference in distance over which light interacts with compounds and tissue.

16. A device according to claim 14, wherein at least one substantially flat area constituting a third area or group of areas is provided and forms a common level between the base level and the top level

17. A device according to claim 12, wherein at least a part of one of said areas is formed by a permeable membrane.

18. A device according to claim 17, wherein the said membrane is permeable to glucose.

19. A method for optically detecting the content of a compound in the body of a living creature, the method comprising:

directing a light source on different areas of an implanted device containing detection means, the distance, between the skin and said detection means, over which light from a light source interacts with compounds and tissue in respect of one area differing from the distance, between the skin and said detection means, over which light from a light source interacts with compounds and tissue in respect of another area;

obtaining light-representing signals by means of said detection means; and

analysing the detected signals, the analysis preferably being based on the difference between the detected signals, to obtain a value for the content of a compound being detected.

21. A method according to claim 19, wherein the compound is glucose.

20. A method for optically detecting the content of a compound in the body of a living creature, the method comprising:

directing a light source on different areas of an implanted device containing detection means;

obtaining light-representing signals by means of said detection means;

transmitting said light-representing signals to an external device; and

analysing the detected signals to obtain a value for the content of the compound being detected.

22. A method according to claim 20, wherein the compound is glucose.