OCT using spectrally resolved bandwidth

• US 20070015969A1
• Filed: 06/05/2006
• Published: 01/18/2007
• Est. Priority Date: 06/06/2005
• Status: Active Grant

• Current Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Original Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Inventors: Kim, Eunha, Condit, Chris, Kumar, Karthik, Kim, Jeehyun, Kemp, Nate, Han, Li-Hsin, Chen, Shaochen, Grant, Robert, Feldman, Marc, Milner, Thomas, Oh, Jung
• Granted Patent: US 7,783,337 B2
• Time in Patent Office: Days
• US Class Current: 600/160
• CPC Class Codes: A61B 1/00096 Optical elements
• CPC Class Codes: A61B 1/00167 Details of optical fibre bundles, e.g. shape or fibre distribution
• CPC Class Codes: A61B 1/00172 with means for scanning
• CPC Class Codes: A61B 5/0066 Optical coherence imaging
• 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 5/0084 for introduction into the body, e.g. by catheters A61B5/1459 takes precedence
• CPC Class Codes: A61B 5/6852 Catheters

Abstract

The present invention is related to a system for optical coherence tomographic imaging of turbid (i.e., scattering) materials utilizing multiple channels of information. The multiple channels of information may be comprised and encompass spatial, angle, spectral and polarization domains. More specifically, the present invention is related to methods and apparatus for utilizing optical sources, systems or receivers capable of providing (source), processing (system) or recording (receiver) a multiplicity of channels of spectral information for optical coherence tomographic imaging of turbid materials. In these methods and apparatus the multiplicity of channels of spectral information that can be provided by the source, processed by the system, or recorded by the receiver are used to convey simultaneously spatial, spectral or polarimetric information relating to the turbid material being imaged tomographically. The multichannel optical coherence tomographic methods can be incorporated into an endoscopic probe for imaging a patient. The endoscope comprises an optical fiber array and can comprise a plurality of optical fibers adapted to be disposed in the patient. The optical fiber array transmits the light from the light source into the patient, and transmits the light reflected by the patient out of the patient. The plurality of optical fibers in the array are in optical communication with the light source. The multichannel optical coherence tomography system comprises a detector for receiving the light from the array and analyzing the light. The methods and apparatus may be applied for imaging a vessel, biliary, GU and/or GI tract of a patient.

Claims

1. An endoscope for a patient comprising:

a light source;

means for producing light;

an optical fiber array comprising a plurality of optical fibers adapted to be disposed in the patient, the optical fiber array transmitting the light from the light source into the patient, and transmitting the light reflected by the patient out of the patient, the plurality of the optical fibers of the array in optical communication with the light source; and

a detector for receiving the light from the array and analyzing the light, the plurality of the optical fibers of the array in optical communication with the detector.

2. An endoscope as described in claim 1 including a tube about which the plurality of optical fibers are disposed.

3. An endoscope as described in claim 2 wherein the tube has grooves that extend longitudinally along the tube, one of the plurality of optical fibers disposed in each of the grooves.

4. An endoscope as described in claim 3 including a probe tip having a reflector disposed in each groove which reflects light from the optical fiber in the groove when the reflector is in the patient and reflects light from the patient to the optical fiber when the array is in the patient.

5. An endoscope as described in claim 4 wherein the light source includes a tunable laser source and means for guiding the light from the light source to the plurality of optical fibers of the array.

6. An endoscope as described in claim 5 wherein the optical fiber is single mode, has a core with cladding disposed about the core, and has a lens at its tip which focuses the light from the core to the reflector and light from the reflector to the core.

7. An endoscope as described in claim 6 wherein the array includes a transparent cover.

8. An endoscope as described in claim 7 wherein the producing means comprises an input arm, the array comprises a sample arm, the detector comprises a reference arm and a detector arm;

and the input arm, the detector arm, the sample arm and the reference arm together form an interferometer.

9. An endoscope as described in claim 8 wherein the reference arm uses RSOD to introduce depth scanning and dispersion compensation to the interferometer.

10. An endoscope as described in claim 9 including an opto-coupler which optically couples light from the input arm into the corresponding optical fibers of the sample arm.

11. An endoscope as described in claim 10 wherein the detector determines structural information about the patient from the intensity of an interference signal from reflected light from corresponding fibers of the sample arm and the reference arm.

12. An endoscope as described in claim 11 wherein the probe tip includes a scanning head which holds N optical fibers, where N is greater than or equal to 2 and is an integer.

13. An endoscope as described in claim 12 wherein the N optical fibers are arranged around the scanning head in parallel and equal spacing.

14. An endoscope as described in claim 13 wherein the probe tip includes a mechanism for moving the scanning head so each of the optical fibers scan an angular range of 360/N degrees.

15. An endoscope as described in claim 14 wherein the moving mechanism includes a mechanism for linear motion which causes the scanning head to rotate.

16. An endoscope as described in claim 15 wherein the linear motion mechanism includes a fiber shaft holder having a shaft channel extending axially along the holder, and N fiber channels are arranged around the holder in parallel with the shaft channel, and a twisting shaft that fits in and conforms with the shaft channel, as the twisting shaft moves in the shaft channel, the holder rotates.

17. An endoscope as described in claim 16 wherein the scanning head has a socket head that conforms with the shaft and causes the scanning head to rotate.

18. An endoscope as described in claim 17 wherein the probe tip includes a guide wire holder disposed on the scanning probe which receives and follows a guide wire when the guide wire is in a blood vessel, biliary tract and possibly GU.

19. An endoscope as described in claim 18 including a spring disposed between the scanning head and the fiber shaft holder which forces the shaft back after the shaft has moved forward.

20. An endoscope as described in claim 3 including a light activated material that turns at least a portion of the tube when light is received by the light activated material.

21. A method for imaging a vessel of a patient comprising the steps of:

transmitting light from a light source into an optical fiber array comprising a plurality of optical fibers in the patient;

transmitting the light reflected by the patient out of the patient;

receiving the light from the array at a detector to transduce a signal; and

analyzing the light signal with processing element.

22. A method as described in claim 21 including the steps of reflecting light from each optical fiber with a corresponding reflector associated with the fiber, and reflecting light from the patient to the associated fiber with a reflector.

23. A method as described in claim 22 including the step of moving each of N optical fibers comprising the optical fiber array an angular range of 360/N degrees.

24. A method as described in claim 23 including the step of applying a linear motion to cause each of the N optical fibers of the optical fiber array to move the angular range.

25. A method as described in claim 24 wherein the step of applying the linear motion includes the step of moving axially forward in parallel with the N optical fibers a twisting shaft through a shaft channel extending axially along a fiber shaft holder having N fiber channels arranged around the holder in parallel with the shaft channel which causes the holder to rotate, each of the N optical fibers disposed in a respective fiber channel of the N fiber channels, the twisting shaft fits in and conforms with the shaft channel, as the shaft moves in the channel.

26. A method as described in claim 25 including the step of guiding the optical fiber array along a guide wire which is received by a guide wire holder when the guide wire is in a blood vessel, biliary tract and possibly GU.

27. An apparatus for studying an object comprising:

means for producing light; and

means for analyzing the light that has reflected from the object based on polarization, space, position or angle.

28. An apparatus for studying an object comprising:

means for producing light; and

means for analyzing the light that has reflected from the object based on polarization.

29. An apparatus for studying an object comprising:

means for producing light; and

means for analyzing the light that has reflected from the object based on space.

30. An apparatus for studying an object comprising:

means for producing light; and

means for analyzing the light that has reflected from the object based on angle.

31. A method for studying an object comprising the steps of:

producing light; and

analyzing the light that has reflected from the object based on polarization, space, position or angle.

32. A method for studying an object comprising the steps of:

producing light; and

analyzing the light that has reflected from the object based on polarization.

33. A method for studying an object comprising the steps of:

producing light; and

analyzing the light that has reflected from the object based on space.

34. A method for studying an object comprising the steps of:

producing light; and

analyzing the light that has reflected from the object based on angle.