Patent ID: 6049727
Filing Date: 2000-04-11
Classification: A61B,G01J,G01N

Abstract:
A method of determining a concentration of a constituent of body fluid in a mammal using in vivo spectroscopy, the method comprising the step of:(a) implanting a sensor system in the mammal by setting the sensor system in place to allow plural measurements to be taken at different time periods from a single in vivo position, the sensor system including a source of light which emits at a plurality of different wavelengths, at least one of the wavelengths being in the infrared region, and a detector for detecting light emitted from the source, the source and the detector located so that (i) the light output from the source interacts with a body fluid before being received by the detector, and (ii) light from each of the different wavelengths has a substantially collinear optical path through the fluid with respect to one another;(b) emitting light from the source;(c) obtaining a signal at an output of the detector which contains spectra of the body fluid at each of the different wavelengths; and(d) analyzing the signal to determine the concentration of the constituent of the body fluid.