Optical imaging or spectroscopy systems and methods

Patent metadata

Field	Value
Publication number	US-9655523-B2
Application number	US-65532509-A
Country	US
Kind code	B2
Filing date	Dec 29, 2009
Priority date	Jun 29, 2007
Publication date	May 23, 2017
Grant date	May 23, 2017

Abstract

Optical imaging or spectroscopy described can use laminar optical tomography (LOT), diffuse correlation spectroscopy (DCS), or the like. An incident beam is scanned across a target. An orthogonal or oblique optical response can be obtained, such as concurrently at different distances from the incident beam. The optical response from multiple incident wavelengths can be concurrently obtained by dispersing the response wavelengths in a direction orthogonal to the response distances from the incident beam. Temporal correlation can be measured, from which flow and other parameters can be computed. An optical conduit can enable endoscopic or laparoscopic imaging or spectroscopy of internal target locations. An articulating arm can communicate the light for performing the LOT, DCS, or the like. The imaging can find use for skin cancer diagnosis, such as distinguishing lentigo maligna (LM) from lentigo maligna melanoma (LMM).

First claim

What is claimed is:

1. A method, comprising:
sourcing light at different wavelengths concurrently to form an incident beam;
communicating the light along an articulated arm that does not use a fiber optic conduit;
scanning a location of the incident beam including the different wavelengths across a target region at a selectable incident angle to the target region;
obtaining an optical response concurrently at different locations at different distances in a first direction from the beam location upon the target region, the different distances corresponding to respective different depths penetrated by the incident beam at the selectable incident angle within the target region;
spectrally separating different wavelengths of the obtained optical response; and
detecting the spectrally separated wavelengths of the obtained optical response from the different locations concurrently to provide information about the target region.

2. The method of claim 1 , in which detecting the spectrally separated wavelengths of the obtained optical response includes detecting a first and second wavelengths of fluorophore emission, wherein the first wavelength of fluorophore emission is different and spectrally separated from the second wavelength of fluorophore emission.

3. The method of claim 2 , in which detecting the spectrally separated wavelengths of the obtained optical response includes detecting the first wavelength of fluorophore emission from a first type of fluorophore and detecting the second wavelength of fluorophore emission from a second type of fluorophore that is different from the first type of fluorophore.

4. The method of claim 3 , in which the spectrally separating different wavelengths of the obtained optical response includes spectrally separating along a linear second direction that is orthogonal to the first direction at a light detector.

5. The method of claim 4 , further comprising:
storing a two-dimensional array of the spectrally separated obtained optical response information from the light detector for different beam locations of the target region; and
using the stored two-dimensional array of the spectrally separated obtained optical response information from the light detector for different beam locations of the target region to construct at least one of:
a three dimensional rendered image of the target region;
an image representing chemical composition of the target region; and
a plurality of images representing information about different depths of the target region.

6. The method of claim 1 , in which the spectrally separating different wavelengths comprises refracting different wavelengths by different amounts.

7. The method of claim 1 , in which the spectrally separating different wavelengths comprises diffracting the different wavelengths by different amounts.

8. The method of claim 1 , in which the spectrally separating different wavelengths includes filtering a first wavelength from a second wavelength.

9. The method of claim 1 , further comprising:
computing, for the multiple different lateral locations, a measured value of a temporal correlation of the scanning optical response; and
computing a first characteristic of the target region using the measured value of a temporal correlation.

10. The method of claim 9 , further comprising:
obtaining, in response to the same scanning, a fluorescence component of the scanning optical response signal; and
using the fluorescence component of the scanning optical response signal to compute a second characteristic of the target region.

11. The method of claim 10 , further comprising:
obtaining, in response to the same scanning, an absorption component of the scanning optical response signal; and
using the absorption component of the scanning optical response signal to compute a third characteristic of the target region.

12. The method of claim 10 , further comprising:
obtaining, in response to the same scanning, an absorption component of the scanning optical response signal, the absorption component comprising at least two different wavelengths of light; and
using the absorption component of the scanning optical response signal to compute a third characteristic of the target region.

13. The method of claim 1 , further comprising using an optical conduit to communicate light to and from the target region.

14. The method of claim 13 , wherein the scanning an incident beam location and obtaining an optical response are carried out for a target location that is internal to a human or animal.

15. The method of claim 1 , wherein the scanning an incident beam location and obtaining an optical response are carried out for a target location that is orthogonal to a longitudinal axis of the optical conduit.

16. The method of claim 1 , further comprising:
scanning the location of the incident beam across a target region comprising skin; and
using the information about the target region to discriminate between first and second skin conditions.

17. The method of claim 1 , further comprising using an oblique angle from the target region for at least one of the scanning or the obtaining the optical response.

18. The method of claim 1 , further comprising:
computing, for the multiple different lateral locations, a measured value of a temporal correlation of the scanning optical response; and
computing a blood flow characteristic of the target region using the measured value of a temporal correlation.

19. The method of claim 1 , further comprising using an oblique angle from the target region for the scanning, and obtaining the optical response from an intersection point between the oblique incident light and detected optical response light pathways.

20. An apparatus comprising:
at least one light source including at least one of a laser, a light-emitting diode, or a lamp, the light source providing at least one wavelength of light, the at least one light source contained in a housing;
a scanner, configured to receive the light from the light source, and configured to scan a beam of the light across a target region at a selectable incident angle to the target region;
a light detector, configured to receive from the target region a scanning response signal at a plurality of distances from a beam location upon the target region, the plurality of distances from the beam location upon the target region corresponding to respective different depths penetrated by the beam at the selectable incident angle within the target region to generate respective different wavelengths of the response signal at the plurality of distances from the beam location upon the target region;
a dispersive element including at least one of a prism, diffraction grating, or one or more dichroic filters, the dispersive element configured with respect to the light detector to direct a first wavelength of the scanning response signal to a different location of the light detector than a second wavelength of the scanning response signal, wherein the second wavelength is different from the first wavelength; and
an articulating arm, configured to communicate light along the articulating arm, between the housing and the target region, without requiring a fiber optic conduit.

21. The apparatus of claim 20 , comprising a signal processor circuit, coupled to the light detector, the signal processor circuit further configured to concurrently process the scanning response signal of the first wavelength and the scanning response signal of the second wavelength; a

Assignees

• Hillman Elizabeth Marjorie Clare
• Burgess Sean A
• Univ Columbia

Inventors

• Hillman Elizabeth Marjorie Clare
• Burgess Sean A

Classifications

• A61B5/0071

  by measuring fluorescence emission · CPC title

• A61B5/0073

  by tomography, i.e. reconstruction of 3D images from 2D projections (A61B5/0066 takes precedence) · CPC title

• G02B26/101

  with both horizontal and vertical deflecting means, e.g. raster or XY scanners (colour television using laser beams scanning a display screen H04N9/3129) · CPC title

• A61B2562/0238

  Optical sensor arrangements for performing transmission measurements on body tissue · CPC title

• G01J3/42

  Absorption spectrometry; Double beam spectrometry; Flicker spectrometry; Reflection spectrometry (beam switching arrangements G01J3/08) · CPC title