Invasive chemometry
The invention relates to methods and devices for assessing one or more components of a selected tissue in an animal. The present invention permits non-invasive assessment of tissue components in a body structure containing multiple tissue types by assessing multiple regions of the animal's body for an optical characteristic of the tissue of interest and separately assessing one or more optical (e.g., Raman or NIR) characteristics of the tissue component for one or more regions that exhibit the optical characteristic of the tissue of interest.
1. A method of assessing a component of a tissue of an animal, the method comprising:
irradiating a plurality of regions of the tissue to generate radiation therefrom;
evaluating first optical data generated from each of said plurality of irradiated regions to identify at least one of said plurality of regions of tissue exhibiting a first optical characteristic of the tissue, said first optical characteristic associated with said first optical property;
obtaining second optical data generated from said at least one identified region in said plurality of regions, wherein said first and said second optical data are generated by different spectroscopic modes, wherein the second optical data is generated by transmitting radiation, generated from said at least one identified region, through a filter, thereby obtaining filtered photons;
assessing said component in said at least one identified region by evaluating said filtered photons for a second optical characteristic associated with said component; and
reporting an identity for said component in accordance with a result of said accessing step.
2. The method of claim 1 , wherein the component is assessed in the tissue in vivo.
3. The method of claim 1 , wherein the second optical characteristic of the component is assessed for at least two identified regions.
4. The method of claim 1 , wherein the second optical characteristic is a Raman shift of light scattered from the identified region that is attributable to the component.
5. The method of claim 1 , wherein the first optical characteristics of the irradiated regions are assessed using multiple optical conduits that optically couple the irradiated regions with a detector.
6. The method of claim 5 , wherein the conduits are optical fibers.
7. The method of claim 6 , wherein the optical fibers are arranged in a coherent bundle.
8. The method of claim 5 , wherein, for each irradiated region, the first and second optical characteristics are assessed using the same optical conduit.
9. The method of claim 5 , wherein, for each irradiated region, the first and second optical characteristics are assessed using multiple optical conduits.
10. The method of claim 5 , wherein the optical conduits extend along a probe inserted into the body of the animal.
11. The method of claim 5 , wherein the optical conduits extend along a probe applied against a body surface of the animal.
12. The method of claim 5 , wherein the optical conduits are rigidly fixed relative to one another.
13. The method of claim 1 , wherein the component is a cell.
14. The method of claim 13 , wherein the component is an abnormal cell of the tissue.
15. The method of claim 1 , wherein the tissue comprises cells of multiple types.
16. The method of claim 1 , wherein the regions are irradiated with substantially monochromatic light.
17. The method of claim 1 , further comprising:
applying a spectral unmixing method to said second optical property to distinguish said second optical characteristic associated with said component from other optical characteristics associated with other components.
18. A device for assessing a component of a tissue of an animal in vivo, the device comprising a radiation source for irradiating multiple regions of an animal body, light being conveyed from the radiation source to each of the regions by at least one discrete optical illumination fiber for each region; a first detector for identifying regions that exhibit a first optical characteristic of the tissue, the first detector being optically coupled with the regions by way of at least one discrete optical detection fiber for each region; a second detector for assessing Raman-shifted radiation scattered by the identified regions, the second detector being optically coupled with the identified regions by way of at least one discrete optical detection fiber for each region, and there being an optical filter interposed between the second detector and the identified regions and; a computer processor operably linked to the second detector for restricting assessment of Raman-shifted scattered radiation to the identified regions and for correlating Raman-shifted radiation scattered by the identified regions with the quantity of the component in the tissue.