Method and apparatus to compensate for melanin and hemoglobin variation in determination of a measure of a glycation end-product or disease state using tissue fluorescence
US8676283B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 26, 2007 |
| Grant date | Mar 18, 2014 |
| Priority date | — |
| Expiry date | Nov 6, 2031 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/14532
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A method of determining a measure of a tissue state (e.g., glycation end-product or disease state) in an individual is disclosed. A portion of the skin of the individual is illuminated with excitation light, then light emitted by the tissue due to fluorescence of a chemical with the tissue responsive to the excitation light is detected. The detected light can be combined with a model relating fluorescence with a measure of tissue state to determine a tissue state. The invention can illuminate the skin and detect responsive light over a time that spans a plurality of cardiac cycles of the individual, which can, as an example, help mitigate the effects of time-varying signals such as those due to hemoglobin. The invention can also determine the amount of light to be directed to the skin, for example by controlling the time that a light source is energized. The amount of illumination light can be determined from a skin reflectance characteristic such as pigmentation or melanin in the skin. Controlling the amount of light directed to the tissue can reduce the dynamic range required of a corresponding optical system, for example by allowing a single system to accurately measure individu…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.