Combined spectral and polarimetry imaging and diagnostics

• US 8,649,008 B2
• Filed: 02/04/2011
• Issued: 02/11/2014
• Est. Priority Date: 02/04/2010
• Status: Active Grant

• Current Assignee: Doheny Eye Institute, University of Southern California
• Original Assignee: Doheny Eye Institute, University of Southern California
• Inventors: Kashani, Amir H., Humayun, Mark S.
• Primary Examiner(s): Chowdhury, Tarifur
• Assistant Examiner(s): Gray, Sunghee Y
• Application Number:
  US13/021,524
• Publication Number:
  US 20110206291A1
• Time in Patent Office: 1,103 Days
• Field of Search: 356/327
• US Class Current: 356/327
• CPC Class Codes: A61B 3/12 for looking at the eye fundus, e.g. ophthalmoscopes A61B3/13 takes precedence
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• CPC Class Codes: A61B 5/0068 Confocal scanning
• 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 5/14555 specially adapted for the eye fundus
• CPC Class Codes: A61B 5/14558 by polarisation
• CPC Class Codes: A61B 5/4842 Monitoring progression or stage of a disease
• CPC Class Codes: G01J 3/2823 Imaging spectrometer
• CPC Class Codes: G01J 4/04 Polarimeters using electric detection means G01J4/02 takes precedence
• CPC Class Codes: G01N 2201/0221 Portable; cableless; compact; hand-held

Abstract

Combined spectral and polarimetry imaging and diagnostic techniques are disclosed, including an imaging system that simultaneously records spatially co-registered spectral and polarization information from an image of a target scene such as an ocular structure or material or device in an around the eye. Image acquisition and image calibration by such an imaging system or an imaging spectrometer or polarimeter are also disclosed. Methods of data storage and image display relevant to medical practice in general and ophthalmology practice specifically are further disclosed.

Claims

1. A snapshot imaging spectrometer-polarimeter system for capturing simultaneous spectral and spatially colocalized polarization states from an image of ocular structure, the system comprising:

one or more focal plane array detectors configured to detect light of one or more selected wavelength ranges;

a fundus camera adapted to receive an image of ocular structure, and including a primary imaging lens and one or more collimating lenses configured along an optical path and to receive the image and focus the image on the one or more focal plane array detectors;

a dispersive optical element configured along the optical path and to disperse the image in two dimensions;

one or more polarizers configured along the optical path;

one or more retarders configured along the optical path;

an acquisition system configured to collect spectral and polarization data from the one or more focal plane array detectors; and

a processing system operative to receive, from the acquisition system, data representing an image of the ocular structure and to calibrate the image for deleterious optical effects of biological optical media represented within the image.

2. The system of claim 1, wherein the image includes, tissue, an implanted device, injected nanoparticles or dye.

3. The system of claim 1, further comprising a field stop aperture configured to limit a field of view of the system.

4. The system of claim 1, further comprising one or more illumination sources configured to direct light of a desired spectrum and/or polarity along the optical path.

5. The system of claim 1, wherein one of the one or more focal plane array detectors comprises a transmissive filter adapted to perform a user-identified transmissive function, the transmissive filter positioned over the focal plane array detector.

6. The system of claim 1, wherein one of the one or more the focal plane array detectors comprises a transmissive filter adapted to perform a user-identified transmissive function, the transmissive filter positioned over the illumination source.

7. The system of claim 1, wherein the dispersive element comprises a 2D diffraction grating.

8. The system of claim 1, wherein one of the one or more focal plane array detectors comprises a digital image sensor comprising three areas of pixels on a detector, the three areas of detectors comprising one area of detectors configured to detect red light, one area of detectors configured to detect green light, and one area of detectors configured to detect blue light.

9. The system of claim 1, wherein one of the one or more focal plane array detectors comprises a monochromatic focal plane array detector.

10. The system of claim 1, further comprising a fundus camera configured to provide an image to the collimating lens.

11. The system of claim 1, further comprising a confocal imaging device configured to provide an image to the one or more focal plane array detectors.

12. The system of claim 11, wherein the confocal imaging device comprises a confocal scanning laser ophthalmoscope.

13. The system of claim 1, further comprising an optical coherence tomographic device configured to provide an image to the one or more focal plane array detectors.

14. The system of claim 1, further comprising an endoscopic or laparoscopic camera configured to provide an image to the one or more focal plane array detectors.

15. The system of claim 14, wherein the endoscopic camera is configured with an intraocular camera.

16. The system of claim 1, wherein the one or more polarizers and one or more retarders are configured as a Mueller matrix imaging polarimeter (MMIP) configured to determine a partial or complete polarization aberration matrix of the image.

17. The system of claim 1, wherein the one or more focal plane detector arrays comprise a single focal plane detector array.

18. The system of claim 1, wherein the one or more focal plane detector arrays comprise a first focal plane detector array configured to detect wavelength data of the image and a second focal plane detector array configured to detect polarization state data of the image, wherein the first focal plane detector array and the second focal plane detector array have spatially coregistered outputs.

19. The system of claim 1, wherein the spectral information from the target scene is spatially coregistered with the polarization states from the scene by a system-transfer calibration matrix.

20. The system of claim 1, further comprising a display configured to display representations of the image.

21. The system of claim 1, wherein the system is further configured to (i) receive average in vitro optical characteristic data as normative data for tissue of interest shown in the image, (ii) compare data or optical characteristics of tissue of interest in the image with normative data for respective tissue, (iii) correct the image by removing deleterious optical effects of the tissue as indicated in the normative data for the tissue of interest.

22. The system of claim 1, wherein the system is further configured to (i) receive data of in vivo optical characteristics for a tissue of interest, (ii) compare data of optical characteristics of a target tissue of interest shown in the image with the received data in (i), (iii) determine a difference spectrum representing an optical medium shown in the image, and (iv) based on the difference spectrum, correct the image.

23. The system of claim 1, wherein the system is further configured to (i) receive data of in vivo optical characteristics for each of a plurality of tissues of interest along an optical path shown in the image, (ii) subtract data obtained in (i) from the image with the received data in (i).

24. The system of claim 1, wherein the deleterious optical effects include anisotropy.

25. The system of claim 1, wherein the deleterious optical effects include absorbance.

26. The system of claim 1, wherein the deleterious optical effects include target fluorescence.

27. The system of claim 1, wherein the deleterious optical effects include scattering.

28. The system of claim 1, further comprising an imaging system configured to produce an image of a region of interest and provide data representing the image to the processing system.

29. The system of claim 28, wherein the imaging system comprises a spectrometer.

30. The system of claim 28, wherein the imaging system comprises a polarimeter.

31. The system of claim 28, wherein the imaging system comprises a confocal optical system.

32. The system of claim 28, wherein the processing system comprises a processor and memory.

33. The system of claim 28, further comprising a display configured to display a representation of the image.

34. A method of calibrating an image of an ocular structure including an optical medium, the method comprising:

receiving combined spectral and polarization data, wherein the data are derived from an image of an ocular structure having an optical medium, that is generated using the snapshot imaging spectrometer-polarimeter system of claim 1; and

removing deleterious optical effects of the ocular media from the data, and calibrating the image for deleterious optical effects of the ocular media.

35. The method of claim 34, further comprising receiving spatially coregistered spectral data from a spectrometer.

36. The method of claim 34, further comprising receiving spatially coregistered polarization data derived from the image.

37. The method of claim 36, further comprising receiving polarization data from a polarimeter.

38. An article of manufacture comprising:

a non-transitory machine readable storage medium; and

executable program instructions embodied in the machine readable storage medium that, when executed by a processor of a programmable computing device, configures the programmable computing device to control the acquisition system of claim 1 receiving an image of an ocular structure including an optical medium, to perform functions for calibrating the image for optical noise, including instructions to;

remove deleterious optical effects of the ocular medium from the data, and calibrate the image for deleterious optical effects of the ocular medium.

39. The article of manufacture of claim 38, further comprising instructions for receiving spectral data from a spectrometer.

40. The article of manufacture of claim 38, further comprising instructions for receiving spatially coregistered polarization data derived from the image.

41. The article of manufacture of claim 40, further comprising instructions for receiving polarization data from a polarimeter.

42. The article of manufacture of claim 38, further comprising instructions for focusing a camera on or in an eye for obtaining the image.

43. The article of manufacture of claim 38, further comprising instructions for tomographic reconstruction of the image into a hyperspectral cube.