Ultrasound imaging system

• US 20070265531A1
• Filed: 05/25/2007
• Published: 11/15/2007
• Est. Priority Date: 09/28/2001
• Status: Abandoned Application

• Current Assignee: Teratech Corporation
• Original Assignee: Teratech Corporation
• Inventors: He, Xingbai, Chang, Peter, Chiang, Alice, Kischell, Eric
• Application Number:
  US11/807,236
• Publication Number:
  US 20070265531A1
• Time in Patent Office: Days
• US Class Current: 600/454
• CPC Class Codes: A61B 8/065 to determine blood output from the heart in general A61B5/029
• CPC Class Codes: A61B 8/4427 Device being portable or laptop-like
• CPC Class Codes: A61B 8/463 characterised by displaying multiple images or images and diagnostic data on one display composite display in devices for short-range imaging with acoustic waves G01S7/52074
• CPC Class Codes: A61B 8/486 involving arbitrary m-mode
• CPC Class Codes: A61B 8/488 involving Doppler signals
• CPC Class Codes: A61B 8/5223 for extracting a diagnostic or physiological parameter from medical diagnostic data for algorithms to analyse biomedical images G06T7/0012
• CPC Class Codes: A61B 8/54 Control of the diagnostic device
• CPC Class Codes: A61B 8/56 Details of data transmission or power supply
• CPC Class Codes: G01S 15/584 with measures taken for suppressing velocity ambiguities, i.e. anti-aliasing
• CPC Class Codes: G01S 15/8979 Combined Doppler and pulse-echo imaging systems
• CPC Class Codes: G01S 15/8981 Discriminating between fixed and moving objects or between objects moving at different speeds, e.g. wall clutter filter
• CPC Class Codes: G01S 7/003 Transmission of data between radar, sonar or lidar systems and remote stations
• CPC Class Codes: G01S 7/52044 Scan converters
• CPC Class Codes: G01S 7/52063 Sector scan display
• CPC Class Codes: G01S 7/52071 Multicolour displays; using colour coding; Optimising colour or information content in displays, e.g. parametric imaging
• CPC Class Codes: G01S 7/5208 with integration of processing functions inside probe or scanhead
• CPC Class Codes: G01S 7/52082 involving a modular construction, e.g. a computer with short range imaging equipment modular ultrasonic medical diagnostic devices A61B8/4411
• CPC Class Codes: G01S 7/52084 related to particular user interfaces special user input means for ultrasonic medical diagnostic devices A61B8/467

Abstract

The present invention is directed to an ultrasound imaging system and method for Doppler processing of data. The ultrasonic imaging system efficiently addresses the data computational and processing needs of Doppler processing. Software executable sequences in accordance with a preferred embodiment of the present invention determines the phase shift and the auto-correlation phase of filtered image data. In a preferred embodiment, the system of ultrasonic imaging also includes a sequence of instructions for Doppler processing that provides the functions for demodulation, Gauss Match filtering, auto-correlation calculation, phase shift calculation, frame averaging, and scan conversion implemented with Single Instruction Multiple Data (SIMD) or Multiple Instruction Multiple Data (MIMD) instructions. In a preferred embodiment, the ultrasound imaging system of the present invention includes a processing module; and memory operable coupled to the processing module, wherein the memory stores operational instructions that cause the processing module to map serial data to vector representation, calculate an auto-correlation function of the data, calculate a phase shift of the auto-correlation function to generate a monotonic function covering all values of the phase shift corresponding to a range of Doppler velocities and display the resultant images, for example, as color images.

Claims

1. An ultrasound system for scanning a region of interest with ultrasound energy to image the region of interest comprising:

a data processing system including a Doppler processing system having a programmable filter and a memory coupled to the processing system, the memory having stored therein a sequence of instructions to apply the filter to an ultrasound image; and

a user interface to adjust color priority of the ultrasound image.

2. The ultrasound system of claim 1 wherein the programmable filter comprises a high pass filter.

3. The ultrasound system of claim 2 wherein the high pass filter comprises a Butterworth filter.

4. The ultrasound system of claim 1 wherein the Doppler parallel computing element including a multiplier and an adder.

5. The ultrasound system of claim 1 wherein the Doppler processing system executes at least one of Single Instruction Multiple Data instructions and Multiple Instruction Multiple Data instructions.

6. The ultrasound system of claim 1 wherein Doppler processing is executed in a computation device having an MMX or floating point processor.

7. The ultrasound system of claim 1 wherein the Doppler processing system further comprises a directional power Doppler mode, a power Doppler mode and a pulsed wave Doppler mode.

8. The ultrasound system of claim 1 further comprising adjustable control for one of at least scan area selection, velocity display, steering angles, color inversion, color gain, color priority, color persistence, color baseline and frame rate.

9. The ultrasound system of claim 1 wherein the programmable filter comprises a wall filter.

10. The ultrasound system of claim 1 wherein the processor determines a tissue motion velocity.

11. The ultrasound system of claim 1 wherein the processor compares a Doppler signal to a threshold value such that if the Doppler signal is larger then the threshold value, a phase shift of the Doppler signal is set to zero.

12. The ultrasound system of claim 11 wherein the threshold value is selected from the group consisting of B-mode value, tissue motion velocity and high pass filtered Doppler velocity.

13. The ultrasound system of claim 1 further comprising a graphical user interface that includes a display of a filter adjustment setting.

14. A method for Doppler processing of an ultrasound image comprising:

processing ultrasound image data with a Doppler processing system having a microprocessor and a memory coupled to the microprocessor having stored therein a sequence of instructions that applies a programmable filter to the image data and executes Doppler processing of the image data; and

performing a Doppler processing operation to form an image of the region of interest.

15. The method of claim 14 further comprising performing Doppler processing including one of color Doppler, directional power Doppler, power Doppler and pulsed wave Doppler.

16. The method of claim 14 further comprising removing low frequency signals from the image data with the filter.

17. The method of claim 14 wherein a color Doppler image is overlaid with a B-mode image.

18. The method of claim 16 further comprising adjusting a wall filter setting to display low velocity tissue motion.

19. The method of claim 14 further comprising filtering the image data with a Butterworth filter.

20. The method of claim 14 further comprising adjusting the filter to image cardiac motion.

21. A computer readable medium having stored therein instructions for causing a processing unit to execute the steps of the method of claim 14.

22. The method of claim 14 wherein the sequence of instructions perform a filter operation further comprising determining a phase shift of an auto-correlation function to generate a monotonic function for all values of the phase shift corresponding to a range of Doppler velocities.

23. The method of claim 14 wherein the sequence of instructions further comprises:

filtering the data to remove low frequency signals;

averaging a plurality of frames of data;

converting phase shift data to an index;

converting the phase shift data from scan to raster coordinates; and

displaying a plurality of images.

24. The method of claim 14 further comprising at least one parallel processing element.

25. The method of claim 24 wherein at least one parallel processing element executes at least one of Single Instruction Multiple Data instructions and Multiple Instruction Multiple Data instructions.

26. The method of claim 14 wherein the Doppler processing further comprises displaying at least one of the presence, direction, and relative velocity of blood flow, perfusion and contour of lumens.

27. The method of claim 14 further comprising providing an adjustable control for at least one of scan area selection, velocity display, steering angles, color inversion, color gain, color priority, color persistence, color baseline and frame rate.

28. The method of claim 14 further comprising determining a phase shift value and optionally setting the phase shift to zero.

29. The method of claim 28 further comprising applying a spatial low pass filter to smooth phase shift values.

30. The method of claim 29 further comprising converting phase shift data to color index data.

31. The method of claim 28 wherein the phase shift is set to zero if the power of a Doppler signal prior to application of a high pass filter is larger than a threshold value.

32. The method of claim 14 further comprising adjusting color priority with an adjustable control.

33. An ultrasound imaging apparatus comprising:

a memory operably coupled to a processing module, wherein the memory stores operational instructions that cause the processing module to;

apply a programmable filter to ultrasound image data;

calculate a phase shift of a Doppler signal to generate a monotonic function for all values of the phase shift corresponding to a range of Doppler velocities;

convert the phase shift to an index; and

display a plurality of images including at least one of color Doppler, directional power Doppler, power Doppler and pulsed wave Doppler.

34. The apparatus of claim 33 wherein the apparatus further comprises a handheld probe operable to transmit an ultrasound image and to obtain data indicative of the flow characteristics of the region of interest.

35. The apparatus of claim 33 wherein the plurality of images includes color Doppler images, directional power Doppler images, power Doppler images and pulsed wave Doppler images.

36. The apparatus of claim 33 further comprising adjustable controls for one of at least scan area selection, velocity display, steering angles, color inversion, color gain, color priority, color persistence, color baseline and frame rate.

37. The apparatus of claim 33 wherein the programmable filter comprises a high pass filter.

38. The method of claim 33 further comprising a graphical user interface including a control for the programmable filter.

39. The apparatus of claim 33 further comprising a transducer array connected to an interface that is connected to a personal computer having a parallel processor.

40. The apparatus of claim 39 wherein the interface includes a beamformer and a system controller.