Method and apparatus for minimizing spectral effects attributable to tissue state variations during NIR-based non-invasive blood analyte determination
US6640117B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 17, 2001 |
| Grant date | Oct 28, 2003 |
| Priority date | — |
| Expiry date | Nov 22, 2021 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/1491
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A method and apparatus for minimizing confounding effects in a noninvasive in-vivo spectral measurement caused by fluctuations in tissue state monitors a selected tissue state parameter spectroscopically and maintains the selected parameter within a target range, at which spectral effects attributable to the changes in the selected parameter are minimized. The invention includes both active and passive control. A preferred embodiment of the invention provides a method and apparatus for minimizing the confounding effects in near IR spectral measurements attributable to shifts in skin temperature at a tissue measurement site. Spectroscopic monitoring of skin temperature at the measurement site provides near-instantaneous temperature readings by eliminating thermal time constants. A thermistor positioned at the measurement site provides active control. The spectrometer and the temperature control device are incorporated into a single instrument for noninvasive measurement of blood glucose concentration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.