Non-invasive tissue glucose level monitoring

• US 7,899,518 B2
• Filed: 09/12/2005
• Issued: 03/01/2011
• Est. Priority Date: 04/06/1998
• Status: Expired due to Fees

• Current Assignee: Masimo Laboratories, Inc. (Masimo Corporation)
• Original Assignee: Masimo Laboratories, Inc. (Masimo Corporation)
• Inventors: Trepagnier, Pierre, Kollias, Nikiforos, Mansfield, James, Brand, Derek, Hopmeier, Michael J., Freeman, Jenny
• Primary Examiner(s): Winakur; Eric F
• Application Number:
  US11/224,690
• Publication Number:
  US 20060195022A1
• Time in Patent Office: 1,996 Days
• Field of Search: 600/310, 600/316, 600/317, 600/365, 600/476, 600/473
• US Class Current: 600/473
• CPC Class Codes: A61B 5/0071 by measuring fluorescence emission
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters

Abstract

Instruments and methods are described for performing non-invasive measurements of analyte levels and for monitoring, analyzing and regulating tissue status, such as tissue glucose levels.

Claims

1. A method of assessing a change in the structural matrix, cellular, or mitochondrial components of living tissue comprising:

using a radiation source to expose living tissue to monochromatic radiation at about a first wavelength;

using the radiation source to expose living tissue to monochromatic radiation at about a second wavelength different from the first wavelength;

using a radiation detector to detect fluorescence emitted by the exposed living tissue in response to the radiation at about the first wavelength;

using the radiation detector to detect fluorescence emitted by the exposed living tissue in response to the radiation at about the second wavelength;

using a processing circuit to derive an indication representative of the change in the structural matrix of the living tissue based on the fluorescence detected;

using the radiation source to expose living tissue to broadband radiation;

using a scattering detector to detect scattering re-emitted from the exposed living tissue in response to the broadband radiation; and

using the processing circuit to derive the indication representative of the change in the structural matrix of the living tissue based also on the scattering detected.

2. The method of claim 1 further comprising:

using the radiation source to expose living tissue to monochromatic radiation at about a third wavelength different from the first wavelength and the second wavelength;

using the radiation detector to detect fluorescence emitted by the exposed living tissue in response to the radiation at about the third wavelength; and

using the processing circuit to derive the indication representative of the change in the structural matrix of the living tissue based also on the fluorescence detected in response to the radiation at about the third wavelength.

3. The method of claim 2 wherein the first wavelength is about 335 nm, the second wavelength is about 370 nm, the third wavelength is about 460 nm and the broadband radiation is in the range of about 280 nm to 1,100 nm.