Near-infrared spectroscopic tissue imaging for medical applications

• US 7,016,717 B2
• Filed: 07/05/2002
• Issued: 03/21/2006
• Est. Priority Date: 07/05/2002
• Status: Expired due to Fees

• Current Assignee: Lawrence Livermore National Security LLC (Government of the United States of America)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Demos, Stavros, Staggs, Michael C.
• Primary Examiner(s): ROBINSON, DANIEL LEON
• Application Number:
  US10/190,231
• Publication Number:
  US 20040006275A1
• Time in Patent Office: 1,355 Days
• Field of Search: 600/473, 600/475, 600/407, 250/330, 250/316.1, 250/338.1, 250/472.1, 348/164
• US Class Current: 600/473
• CPC Class Codes: A61B 1/043 for fluorescence imaging
• CPC Class Codes: A61B 1/063 for monochromatic or narrow-band illumination
• CPC Class Codes: A61B 1/0638 providing two or more wavelengths
• CPC Class Codes: A61B 1/0646 with illumination filters
• CPC Class Codes: A61B 1/307 for the urinary organs, e.g. urethroscopes, cystoscopes
• CPC Class Codes: A61B 1/313 for introducing through surgical openings, e.g. laparoscopes
• CPC Class Codes: A61B 5/0071 by measuring fluorescence emission
• CPC Class Codes: A61B 5/0075 by spectroscopy, i.e. measuring spectra, e.g. Raman spectroscopy, infrared absorption spectroscopy A61B5/0071 takes precedence
• CPC Class Codes: A61B 5/0086 using infrared radiation
• CPC Class Codes: G01N 21/49 within a body or fluid
• CPC Class Codes: G01N 21/6445 Measuring fluorescence polarisation

Abstract

Near infrared imaging using elastic light scattering and tissue autofluorescence are explored for medical applications. The approach involves imaging using cross-polarized elastic light scattering and tissue autofluorescence in the Near Infra-Red (NIR) coupled with image processing and inter-image operations to differentiate human tissue components.

Claims

1. A diagnostic method, comprising:

interrogating one or more tissue components with a directed electromagnetic radiation source having one or more substantially narrow predetermined wavelengths,

detecting a scattered electromagnetic radiation and a near infrared autofluorescence emission having one or more wavelengths and polarization states from said tissue components; and

characterizing said tissue components by performing inter-image operations on said detected scattered radiation and said near infrared autofluorescence emission to enhance image contrast and visibility of said tissue components in a specimen.

2. The method of claim 1, wherein said detecting step includes a device selected from a liquid nitrogen cooled CCD camera, a two-dimensional array detector, an avalanche CCD photodetector, a photomultiplier and a photodiode capable of point by point scanning.

3. The method of claim 1, wherein said detecting step includes collection of a near-infrared autofluorescence emission having a predetermined spectral band generated by said tissue components after illumination by said source.

4. The method of claim 3, wherein said near infrared autofluorescence emission further comprises electromagnetic radiation in the near-infra red spectral region between about 600 nm and about 1500 nm.

5. The method of claim 3, wherein said electromagnetic radiation source is polarized and said near-infrared autofluorescence emission is analyzed.

6. The method of claim 5, wherein said electromagnetic radiation source is linearly polarized and a parallel-polarized component of said near-infrared autofluorescence emission is analyzed.

7. The method of claim 5, wherein said electromagnetic source is linearly polarized and a perpendicularly polarized component of said near-infrared autofluorescence emission is analyzed.

8. The method of claim 5, wherein said electromagnetic source is circularly polarized and a same circular polarization orientation of said near-infrared autofluorescence emission is analyzed.

9. The method of claim 8, wherein said near-infrared autofluorescence emission having an opposite circular polarization orientation with respect to said electromagnetic radiation source is analyzed.

10. The method of claim 5, wherein said electromagnetic source is elliptically polarized and a same elliptical polarization orientation of said near-infrared autofluorescence emission is analyzed.

11. The method of claim 10, wherein an orthogonal elliptical polarization of said near-infrared autofluorescence emission is analyzed.

12. The method of claim 1, wherein said electromagnetic source is polarized and said scattered electromagnetic radiation is analyzed.

13. The method of claim 12, wherein said electromagnetic source is polarized and an orthogonal polarization component of said scattered electromagnetic radiation is analyzed.

14. The method of claim 12, wherein said polarized electromagnetic source is selected from, linear, circular or elliptical polarization.

15. The method of claim 12, wherein said scattered electromagnetic radiation is in the near infra-red between about 600 nm and about 1500 nm.

16. The method of claim 1, wherein a plurality of real time images produced from said tissue components are visualized by a device.

17. The method of claim 16, wherein said characterizing step comprises the further step of image processing said plurality of real time images by a device.

18. The method of claim 17, wherein one or more inter-image operations are performed by said device on said images, wherein said device is a computer having image processing software and one or more display means.

19. The method of claim 1, wherein said detected scattered radiation having a cross-polarized component with respect to said electromagnetic radiation source is analyzed.

20. The method of claim 1, wherein one or more predetermined illumination spectral bands is selected from said electromagnetic radiation and inter-image operations are performed by a device on a detected scattered radiation produced from said illumination spectral bands to enhance image contrast and visibility of said tissue components in a specimen.

21. The method of claim 20, wherein a cross-polarized component of said detected scattered radiation with respect to said electromagnetic source from said scattered one or more spectral bands is analyzed.

22. The method of claim 18, wherein said inter-image operations are selected between at least two images from a near-infrared cross-polarized light scattering image of a first wavelength, a near-infrared cross-polarized light scattering image of a first spectral band, a near-infrared cross-polarized light scattering image of a second wavelength, a near-infrared cross-polarized light scattering image of a second spectral band, a near-infrared parallel-polarized light scattering image of a first wavelength, a near-infrared parallel-polarized light scattering image of a second wavelength, a near-infrared parallel-polarized light scattering image of a first spectral band, a near-infrared parallel-polarized light scattering image of a second spectral band, a near-infra-red Autofluorescence image under a first excitation wavelength, a near-infra-red Autofluorescence image under a second excitation wavelength, a near-infra-red Autofluorescence image in a first emission spectral band, a near-infra-red Autofluorescence image in a second emission spectral band, an orthogonal-polarization component of said near-infrared Autofluorescence image produced by a polarized excitation, and a parallel-polarization component of said near-infrared Autofluorescence image produced by said polarized excitation to enhance image contrast and visibility of one or more human tissue components.

23. The method of claim 1, wherein said method is used to image and differentiate malignant tumors from benign tumors and normal tissue.

24. The method of claim 1, wherein said method is used to enhance image visibility and tissue component contrast.

25. The method of claim 1, wherein said source comprises electromagnetic radiation having a wavelength of at least 500 nm.

26. The method of claim 1, wherein said tissue components comprise human tissue.

27. The method of claim 26, wherein said tissue components are selected from normal, abnormal, organs, vascular, and nerve tissue components.