Optical imaging or spectroscopy systems and methods

• US 20100168586A1
• Filed: 12/29/2009
• Published: 07/01/2010
• Est. Priority Date: 06/29/2007
• Status: Active Grant

• Current Assignee: Trustees Of Columbia University In The City Of New York (Columbia University)
• Original Assignee: Trustees Of Columbia University In The City Of New York (Columbia University)
• Inventors: Hillman, Elizabeth Marjorie Clare, Burgess, Sean A.
• Granted Patent: US 9,655,523 B2
• Time in Patent Office: Days
• US Class Current: 600/476
• CPC Class Codes: A61B 2562/0238 Optical sensor arrangements for performing transmission measurements on body tissue
• CPC Class Codes: A61B 2562/0242 for varying or adjusting the optical path length in the tissue
• CPC Class Codes: A61B 5/0064 Body surface scanning
• CPC Class Codes: A61B 5/0066 Optical coherence imaging
• CPC Class Codes: A61B 5/0071 by measuring fluorescence emission
• CPC Class Codes: A61B 5/0073 by tomography, i.e. reconstruction of 3D images from 2D projections A61B5/0066 takes precedence
• 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 5/0088 for oral or dental tissue
• CPC Class Codes: A61B 5/444 Evaluating skin marks, e.g. mole, nevi, tumour, scar
• CPC Class Codes: A61B 5/445 Evaluating skin irritation or skin trauma, e.g. rash, eczema, wound, bed sore
• CPC Class Codes: G01J 3/2889 Rapid scan spectrometers; Time resolved spectrometry
• CPC Class Codes: G01J 3/42 Absorption spectrometry; Double beam spectrometry; Flicker spectrometry; Reflection spectrometry beam switching arrangements G01J3/08
• CPC Class Codes: G01J 3/457 Correlation spectrometry, e.g. of the intensity G01J3/453 takes precedence
• CPC Class Codes: G02B 23/2476 Non-optical details, e.g. housings, mountings, supports
• CPC Class Codes: G02B 26/101 with both horizontal and vertical deflecting means, e.g. raster or XY scanners colour television using laser beams scanning a display screen H04N9/3129

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).

Claims

1. A method comprising:

sourcing light to form an incident beam;

scanning a location of the incident beam across a target region;

obtaining an optical response at different locations at different distances in a first direction from the beam location upon the target region;

dispersing different wavelengths of the optical response; and

detecting the dispersed wavelengths of the optical response from the different locations concurrently to provide information about the target region.

2. The method of claim 1, in which sourcing the light includes sourcing light at different wavelengths.

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

4. The method of claim 3, in which detecting the dispersed wavelengths of the 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.

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

6. The method of claim 5, comprising:

storing a two-dimensional array of response information from the light detector for different beam locations of the target region; and

using the stored two-dimensional array of 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.

7. The method of claim 1, in which dispersing different wavelengths comprises refracting different wavelengths by different amounts.

8. The method of claim 1, in which dispersing different wavelengths comprises diffracting the different wavelengths by different amounts.

9. The method of claim 1, in which dispersing different wavelengths includes filtering a first wavelength from a second wavelength.

10. The method of claim 1, comprising:

computing, for the multiple different lateral locations, a temporal correlation of the scanning optical response; and

computing a first characteristic of the target region using the temporal correlation.

11. The method of claim 10, 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.

12. The method of claim 11, 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.

13. The method of claim 11, 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.

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

15. The method of claim 14, wherein 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.

16. The method of claim 1, wherein 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.

17. The method of claim 1, 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.

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

19. An apparatus comprising:

at least one light source providing at least one wavelength of light;

a scanner, configured to receive the light from the light source, and configured to scan a beam of the light across a 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; and

a wavelength separator, 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.

20. The apparatus of claim 19, comprising:

a signal processor, coupled to the light detector, the signal processor configured to concurrently process the scanning response signal of the first wavelength and the scanning response signal of the second wavelength; and

wherein the lateral distances define a linear first direction, and wherein the wavelength separator is configured to spatially separate wavelengths of the scanning response signal in a linear second direction that is orthogonal to the first direction;

wherein the light detector includes a two-dimensional array of light detector elements, and is configured to detect different wavelengths of the scanning response signal along a first dimension of the two-dimensional array, and to detect along a second dimension of the two-dimensional array optical responses from the different lateral distances from the beam location, and wherein the first and second dimensions of the two-dimensional array are orthogonal to each other, and comprising an imaging data memory including a two-dimensional array of memory locations for corresponding scanning locations of the target region, each two-dimensional array of memory locations storing data from the two-dimensional array of light detectors for a particular scanning location of the target region;

wherein the light source comprises;

a first laser, providing laser light at the first wavelength; and

a second laser, providing laser light at the second wavelength that is different from the first wavelength, and wherein the first wavelength of the scanning response signal is in response to the first wavelength of laser light provided by the first laser, and wherein the second wavelength of the scanning response signal is in response to the second wavelength of laser light provided by the second laser;

wherein the first wavelength of the scanning response signal is in response to a first emission wavelength of a first fluorophore, and wherein the second wavelength of the scanning response signal is in response to a second emission wavelength of a second fluorophore of the same type as the first fluorophore or of a different type than the first fluorophore; and

wherein the apparatus further comprises;

a beam splitter configured to communicate light with the scanner and the wavelength separator; 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.