HEMOGLOBIN CONTRAST IN MAGNETO-MOTIVE OPTICAL DOPPLER TOMOGRAPHY, OPTICAL COHERENCE TOMOGRAPHY, AND ULTRASOUND IMAGING METHODS AND APPARATUS

• US 20080154128A1
• Filed: 10/18/2007
• Published: 06/26/2008
• Est. Priority Date: 05/27/2005
• Status: Active Grant

• Current Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Original Assignee: CardioSpectra, Inc. (Koninklijke Philips N.V.)
• Inventors: Milner, Thomas E.
• Granted Patent: US 8,355,776 B2
• Time in Patent Office: Days
• US Class Current: 600/427
• CPC Class Codes: A61B 2576/00 Medical imaging apparatus involving image processing or analysis A61B1/00009, A61B6/52 and A61B8/52 take precedence; image processing per se G06T; details of algorithms for analysing medical images G06T7/0012
• CPC Class Codes: A61B 5/0035 adapted for acquisition of images from more than one imaging mode, e.g. combining MRI and optical tomography
• CPC Class Codes: A61B 5/0066 Optical coherence imaging
• CPC Class Codes: A61B 5/026 Measuring blood flow A61B3/1233, A61B3/1241 take precedence
• CPC Class Codes: A61B 5/0261 using optical means, e.g. infrared light
• CPC Class Codes: A61B 5/0275 using tracers, e.g. dye dilution
• CPC Class Codes: A61B 5/05 Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves impedance plethysmography A61B5/0295; measuring movement of the entire body or parts thereof A61B5/11; detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof A61B5/24
• CPC Class Codes: A61B 5/0515 Magnetic particle imaging
• CPC Class Codes: A61B 5/6852 Catheters
• CPC Class Codes: A61B 5/725 using specific filters therefor, e.g. Kalman or adaptive filters A61B5/316 take precedence
• CPC Class Codes: A61B 8/06 Measuring blood flow measuring volume flow in general G01F, e.g. G01F1/66, G01F1/72; measuring speed of fluids in general G01P5/00
• CPC Class Codes: A61B 8/13 Tomography A61B8/10, A61B8/12 take precedence; tomography for radiation diagnosis A61B6/02
• CPC Class Codes: A61B 8/488 involving Doppler signals
• CPC Class Codes: A61N 2/02 using magnetic fields produced by coils, including single turn loops or electromagnets A61N2/12 takes precedence
• CPC Class Codes: G01N 21/1717 with a modulation of one or more physical properties of the sample during the optical investigation, e.g. electro-reflectance
• CPC Class Codes: G01N 21/4795 spatially resolved investigating of object in scattering medium in vivo A61B

Abstract

Provided herein are systems, methods, and compositions for the use of optical coherence tomography for detection of cells.

Claims

1. A system for imaging, comprising:

a magnet for applying a magnetic field to the vessels to be imaged, wherein the applied magnetic field interacts with hemoglobin within the vasculature; and

an optical coherence tomography apparatus for detecting magnetic movement of the hemoglobin within the vasculature.

2. The system of claim 1, wherein the magnetic field is oscillating.

3. The system of claim 1, wherein the magnet comprises a solenoid coil with a ferrite core.

4. The system of claim 3, wherein the optical coherence tomography apparatus further comprises a sample arm, and wherein a probe is coupled to the sample arm of the optical coherence tomography apparatus and the magnet.

5. The system of claim 4, wherein the optical coherence tomography apparatus is a magneto-motive optical Doppler tomography imaging system for detecting the blood flow affected by the magnetic field.

6. The system of claim 5, wherein the magneto-motive optical Doppler tomography system comprises:

a light source generating light energy;

an interferometer coupled to the light energy, wherein the interferometer includes a reference and sample light paths coupled to a light splitter;

a modulator coupled to the interferometer for modulating the optical path length difference in the reference arm and the sample arm;

a scanner coupled to the sample arm for scanning a biological sample;

a rapid scanning optical delay line coupled to the reference arm;

a photodetector coupled to the interferometer for detecting backscattered radiation received by the interferometer from the scanner to detect interference fringes; and

a processor for processing the reflected light energy from the reference arm and a signal reflected off of the moving blood flow to produce a tomographic image and a tomographic flow velocity image.

7. The system of claim 6, wherein the magneto-motive optical Doppler tomography system includes a scanning element to permit three dimensional scans.

8. The system of claim 7, wherein the magneto-motive optical Doppler tomography system includes a dual-balanced photodetector.

9. The system of claim 8, wherein the magneto-motive optical Doppler tomography system includes a circulator coupled to the interferometer and the photodetector.

18. The apparatus of claim 4, wherein the optical coherence tomography system for detecting blood flow is a spectral domain phase sensitive optical coherence tomography system.

19. The apparatus of claim 4, wherein the phase sensitive optical coherence tomographic imaging modality is a swept source phase sensitive optical coherence tomography system including a tunable swept source laser and an optical clock to sample interference fringe data uniformly spaced in the optical frequency domain.

10. A method for imaging a blood flow, comprising:

applying a magnetic field to the blood flow, wherein the blood flow comprises a plurality of hemoglobin molecules and wherein the magnetic field interacts with the hemoglobin to cause a change in the blood flow; and

detecting the blood flow by detecting the change in the blood flow caused by the interaction with the hemoglobin molecules with the magnetic field, wherein the change is detected using a optical coherence tomography system.

11. The method of claim 10, wherein the applying of the magnetic field comprises temporally oscillating the magnetic field.

12. The method of claim 11, further comprising coupling the optical coherence tomography system and the magnetic field to a probe.

13. The method of claim 12, wherein the detecting the blood flow by detecting the change in the blood flow caused by the interaction with the hemoglobin molecules, wherein the change is detected using a magnetomotive optical Doppler tomography imaging system.

14. The method of claim 13, wherein the magneto-motive optical Doppler tomography system comprises the method of

providing light energy through an interferometer;

phase modulating the light energy in the interferometer at a modulation frequency;

continuously scanning a blood flow sample with the light energy through the interferometer, wherein the blood flow sample includes a blood flow therein and a structure in which the blood flow is defined;

detecting the signal reflected off the moving blood sample and the interference fringes of the light energy backscattered from moving blood sample; and

data processing Doppler frequency changes of the detected backscattered interference fringes with respect to said modulation frequency at each pixel of a scanned image to continuously measure the interference fringe intensities to obtain time dependent power spectra for each pixel location in a data window in a continuous scan from which a tomographic image of the blood flow in and the structure of said scanned blood flow sample is formed.

15. The method of claim 13, wherein the modulation frequency is zero.

16. The method of claim 14, where detecting the interference fringes of light energy backscattered from the moving blood sample includes reducing the light source noise from the interference signal with a dual balanced photodetector.

17. The method of claim 15, further including improving imaging speed with a hardware in-phase and a quadrature demodulator with at least one high-bandpass filter.

20. The method of claim 10, wherein the detecting of the change in the blood flow caused by the interaction with the hemoglobin molecules is detected using a spectral domain phase sensitive optical coherence tomography system.

21. The method of claim 14, wherein the detecting of the change in the blood flow caused by the interaction with the hemoglobin molecules is detected using a swept source phase sensitive optical coherence tomography system.

22. An apparatus for imaging a blood flow comprising:

a magnetic field generator for applying a magnetic field to the blood flow, wherein the blood flow comprises hemoglobin molecules; and

an ultrasound detection system for detecting the blood flow while it is in the presence of the magnetic field.

23. The apparatus of claim 22, wherein the ultrasound detection system comprises a probe for transmitting and receiving sound energy to and from a subject and the probe includes the magnetic field generator.