Apparatus and method for imaging objects with wavefields

• US 20060287596A1
• Filed: 05/17/2006
• Published: 12/21/2006
• Est. Priority Date: 08/29/1996
• Status: Abandoned Application

• Current Assignee: Biotex Pharma Investments, LLC
• Original Assignee: Techniscan, Inc.
• Inventors: Borupt, David T., Johnson, Steven A., Berggren, Michael J., Wiskin, James
• Application Number:
  US11/436,989
• Publication Number:
  US 20060287596A1
• Time in Patent Office: Days
• US Class Current: 600/437
• CPC Class Codes: A61B 5/4312 Breast evaluation or disorder diagnosis A61B5/0091 takes precedence
• CPC Class Codes: A61B 5/7257 using Fourier transforms
• CPC Class Codes: A61B 8/0825 for diagnosis of the breast, e.g. mammography
• CPC Class Codes: A61B 8/14 Echo-tomography
• CPC Class Codes: A61B 8/15 Transmission-tomography
• CPC Class Codes: A61B 8/406 using means for diagnosing suspended breasts
• CPC Class Codes: A61B 8/4209 by using holders, e.g. positioning frames
• CPC Class Codes: A61B 8/4281 characterised by sound-transmitting media or devices for coupling the transducer to the tissue
• CPC Class Codes: A61B 8/4483 characterised by features of the ultrasound transducer
• CPC Class Codes: A61B 8/485 involving measuring strain or elastic properties
• CPC Class Codes: G01S 13/89 for mapping or imaging
• CPC Class Codes: G01S 15/895 characterised by the transmitted frequency spectrum
• CPC Class Codes: G01S 15/8977 using special techniques for image reconstruction, e.g. FFT, geometrical transformations, spatial deconvolution, time deconvolution
• CPC Class Codes: G06T 11/001 Texturing; Colouring; Generation of texture or colour inpainting G06T5/77

Abstract

A transmission wave field imaging method, comprising the transmission of an incident wave field into an object, the incident wave field propagating into the object and, at least, partially scattering. Also includes the measuring of a wave field transmitted, at least in part, through an object to obtain a measured wave field, the measured wave field based, in part, on the incident wave field and the object. Additionally, the processing of the measured wave field utilizing a parabolic approximation reconstruction algorithm to generate an image data set representing at least one image of the object.

Claims

1. A reflection tomography device, comprising:

a transmitter for transmitting an incident wave field into an object, the incident wave field propagating into the object and, at least, partially reflecting;

a receiver, having an array of elements, receiving a reflected wave field reflected from the object, the reflected wave field being defined, in part, by the incident wave field and the object;

a beamformer forming RF beam signals from the reflected wave field based on beamformer delays; and

a processor module acquiring images based on the RF beam signals, the processor module adjusting the beamformer delay to perform brightness phase aberration correction utilizing a gradient algorithm to analyze the image.

2. The device of claim 1, wherein the processor module comprises a plurality of processors operated in parallel.

3. The device of claim 1, wherein the processor module is implemented on one of a personal computer, a hand-held device, a multi-processor system and a network PC.

4. The device of claim 1, wherein the processor module repeatedly adjusts the beamformer delays such that a brightness function in a region of interest is maximized.

5. The device of claim 1, wherein the beamformer is loaded with at least two different sets of beamformer delays associated with a single focal zone along a single receive beam along which the array of elements receives the reflected wave field.

6. The device of claim 1, wherein the processor module acquires, based on common reflected wave fields, initial and new images utilizing initial beamformer delays and adjusted beamformer delays, respectively.

7. The device of claim 1, wherein the processor module acquires, based on common reflected wave fields, initial and new b-scan images to perform the brightness phase aberration correction.

8. The device of claim 1, wherein the processor module loads new beamformer delays in the beamformer, the new beamformer delays being adjusted from prior beamformer delays by a predetermined time delay perturbation.

9. The device of claim 1, wherein the processor module computes an image intensity for a region of interest from first and second images acquired from a common reflected wave field.

10. The device of claim 1, wherein the processor module computes an image intensity for a region of interest from first and second images acquired from a common reflected wave field, the processor module updating the beamformer delays based on a comparison of the image intensities for the first and second images.

11. The device of claim 1, wherein the processor module adjusts the beamformer delays based on a conjugate gradient based algorithm.

12. The device of claim 1, wherein the transmitter and receiver utilize a common array of elements for transmit and receive operations.

13. The device of claim 1, wherein the transmitter and receiver utilize a different array of elements located proximate one another on a common side of an object for transmit and receive operations.

14. The device of claim 1, further comprising a display for displaying the images as at least one of B-scan images, speed of sound images and attenuation images.

15. The device of claim 1, wherein at least one of the receiver and the transmitter includes transducer elements arranged in at least one of a circular array, a linear array, a 2D planar array and a checkerboard 2D array.

16. The device of claim 1, wherein the device is a breast scanner and the processing module generates the images during a breast scan.

17. The device of claim 1, wherein the transmitter and receiver repeat the transmitting and receiving operations at multiple slices within the object to collect a 3D volume of data.

18. A method for performing reflection tomography, comprising:

transmitting an incident wave field into an object, the incident wave field propagating into the object and, at least, partially reflecting;

receiving a reflected wave field reflected from the object, the reflected wave field being defined, in part, by the incident wave field and the object;

generating RF beam signals from the reflected wave field based on beamformer delays;

processing the RF beam signals to form images;

utilizing a gradient algorithm to analyze the images; and

adjusting the beamformer delay to perform brightness phase aberration correction based on a result of the gradient algorithm analysis.

19. The method of claim 18, wherein the processing is implemented on one of a personal computer, a hand-held device, a multi-processor system and a network PC.

20. The method of claim 18, wherein the adjusting repeatedly adjusts the beamformer delays such that a brightness function in a region of interest is maximized.

21. The method of claim 18, further comprising loading a beamformer with at least two different sets of beamformer delays associated with a single focal zone along a single receive beam along which the array of elements receives the reflected wave field.

22. The method of claim 18, wherein the processing forms initial and new images, based on common reflected wave fields, utilizing initial beamformer delays and adjusted beamformer delays, respectively.

23. The method of claim 18, wherein the processing forms initial and new B-scan images, based on common reflected wave fields, to perform the brightness phase aberration correction.

24. The method of claim 18, further comprising loading new beamformer delays in the beamformer, the new beamformer delays being adjusted from prior beamformer delays by a predetermined time delay perturbation.

25. The method of claim 18, further comprising computing image intensities for a region of interest from first and second images acquired from a common reflected wave field.

26. The method of claim 18, further comprising computing image intensities for a region of interest from first and second images acquired from a common reflected wave field, and updating the beam former delays based on a comparison of the image intensities for the first and second images.

27. The method of claim 18, wherein the adjusting adjusts the beamformer delays based on one of a conjugate gradient based algorithm.

28. The method of claim 18, wherein the transmitting and receiving utilize a common array of elements for transmit and receive operations.

29. The method of claim 18, wherein the transmitting and receiving utilize different arrays of elements located proximate one another on a common side of an object for transmit and receive operations.

30. The method of claim 18, further comprising displaying the images as at least one of B-scan images, speed of sound images and attenuation images.

31. The method of claim 18, wherein the method performs a breast scan and the processing generates the images during the breast scan.

32. A method of calibrating a transmission wave field imaging device, the method comprising:

transmitting an incident wave field into an object, the incident wave field propagating into a phantom and, at least, partially scattering;

measuring a wave field transmitted, at least in part, through the phantom to obtain a measured wave field, the measured wave field being based, in part, on the incident wave field and the phantom, wherein the transmitting and receiving are dependent on at least one transmitter characteristic and receiver characteristic; and

processing the measured wave field to obtain at least one calibration value that quantifies the transmitter and receiver characteristics.

33. The method of claim 32, wherein the processing is based on calibration parameters including at least one of phantom position, phantom radius, speed of sound through the phantom, receiver characteristics and transmitter characteristics.

34. The method of claim 32, wherein the phantom includes at least one cylinder.

35. The method of claim 32, further comprising determining a transducer field of a transmitter;

and calibrating the transducer field.

36. The method of claim 32, further comprising determining a receiver sensitivity pattern;

and calibrating the receiver sensitivity pattern.

37. The method of claim 32, further comprising creating at least one of a receiver model and a transmitter model that are used in the processing to obtain the at least one calibration value.

38. The method of claim 32, further comprising measuring physical locations of a transmitter and a receiver relative to a region to be imaged, the physical locations being used in the processing to obtain the at least one calibration value.