Cancer diagnosis device utilizing laser beam pulses
Fluorescent spectral analysis apparatus
Tissue metabolism measuring apparatus Patent #: 4832035
ApplicationNo. 287847 filed on 12/21/1988
US Classes:600/433, Using flexible catheter356/39, BLOOD ANALYSIS356/341, For light comparison means356/432, FOR LIGHT TRANSMISSION OR ABSORPTION600/342Light conducting fiber inserted in body
ExaminersPrimary: Shay, David M.
Attorney, Agent or Firm
Foreign Patent References
International ClassA61B 005/00
AbstractMethods 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.