Apparatus for determining the concentration of a tissue pigment of known absorbance, in vivo, using the decay characteristics of scintered electromagnetic radiation
US5119815A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 21, 1988 |
| Grant date | Jun 9, 1992 |
| Priority date | — |
| Expiry date | Dec 21, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/1791
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Methods and apparatus using the principles of time-resolved spectroscopy are disclosed. The present invention employs incident light pulses of sufficiently short duration to permit the rate of the rise and decay of such pulses to be measured. Consequently, the rate of decay, u, permits a determination of the concentration of an absorptive pigment, such as hemoglobin. The present invention also allows the precise path length the photons travel to be determined. Using this path length information and by measuring changes in optical density using known continuous light (CW) spectrophotometry systems, the methods and apparatus disclosed allow changes in the concentration of an absorptive pigment to be correctly be measured. From these data, the oxygenation state of a tissue region, such as the brain, can be accurately determined in real time.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.