Quantitative color flow

• US 5,443,071 A
• Filed: 10/11/1994
• Issued: 08/22/1995
• Est. Priority Date: 10/11/1994
• Status: Expired due to Term

• Current Assignee: Siemens Medical Solutions USA Incorporated (Siemens AG)
• Original Assignee: Siemens Medical Systems, Inc. (Siemens AG)
• Inventors: Kim, Jin, Banjanin, Zoran B.
• Primary Examiner(s): MANUEL, GEORGE C
• Application Number:
  US08/322,113
• Time in Patent Office: 315 Days
• Field of Search: 128/661.08, 128/661.09, 128/661.10, 73/861.25, 73/861.26
• US Class Current: 600/455
• 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: G01S 15/8927 using simultaneously or sequentially two or more subarrays or subapertures
• CPC Class Codes: G01S 15/8984 Measuring the velocity vector

Abstract

Method for providing a quantitative color flow display of moving matter using an ultrasound imaging system, the display being formed of pixels on a display device, which method includes the steps of: (a) transmitting acoustic beams to a region of interest in the body, which region of interest includes the moving matter; (b) receiving echo beams from the region of interest; (c) obtaining, at each portion of the region of interest, which portion is referred to as a pixel, a measure of velocity of moving matter in the pixel and a measure of direction of the velocity of the moving matter in the pixel; (d) determining a maximum of the measure of velocity at each pixel in the region of interest over a predetermined period of time and the measure of direction of the maximum velocity; and (e) displaying the measures of velocity of the pixels for the predetermined period of time wherein the measures of velocity and the measure of direction of the velocity are displayed using a color indicator which is relative to the maximum measure of velocity at each pixel and to the measure of direction of the maximum velocity.

Claims

1. A method for providing a quantitative color flow display of moving matter using an ultrasound imaging system, the display being formed of pixels on a display device, which method comprises the steps of:

transmitting acoustic beams to a region of interest in the body, which region of interest includes the moving matter;

receiving echo beams from the region of interest;

obtaining, at each portion of the region of interest, which portion is referred to as a pixel, a measure of velocity of moving matter in the pixel and a measure of direction of the velocity of the moving matter in the pixel;

determining a maximum of the measure of velocity at each pixel in the region of interest over a predetermined period of time and the measure of direction of the maximum velocity; and

displaying the measures of velocity of the pixels for the predetermined period of time wherein the measures of velocity and the measure of direction of the velocity are displayed using a color indicator which is relative to the maximum measure of velocity at each pixel and to the measure of direction of the maximum velocity.

2. The method of claim 1 wherein the color indicator comprises a circle of colors wherein velocity at the value of the maximum and in the same direction as the maximum is a first color and other values of velocity and direction have different color.

3. The method of claim 2 wherein the first color is red and a velocity in a direction opposite to the direction of the maximum velocity is blue.

4. A method for providing a quantitative color flow display of moving matter using an ultrasound imaging system, the display being formed of pixels on a display device, which method comprises the steps of:

transmitting acoustic beams to a region of interest in the body, which region of interest includes the moving matter;

receiving echo beams from the region of interest;

obtaining, at each portion of the region of interest, which portion is referred to as a pixel, a measure of power of the echo beam from the pixel;

determining a maximum of the measure of power at each pixel in the region of interest over a predetermined period of time; and

displaying the measures of power of the pixels for the predetermined period of time using a color indicator which is relative to the maximum power at each pixel.

5. The method of claim 4 wherein the color indicator comprises a circle of colors wherein power at the value of the maximum is a first color and other values of power have one or more different colors.

6. The method of claim 5 wherein the first color is red.

7. A method for providing a quantitative color flow display of moving matter using an ultrasound imaging system, the display being formed of pixels on a display device, which method comprises the steps of:

transmitting acoustic beams to a region of interest in the body, which region of interest includes the moving matter;

receiving echo beams from the region of interest;

obtaining, at each portion of the region of interest, which portion is referred to as a pixel, a measure of velocity of moving matter in the pixel;

determining a maximum of the measure of velocity in the pixels in the region of interest over a predetermined period of time; and

displaying the measures of velocity of the pixels for the predetermined period of time using a color indicator which is relative to the maximum of the measures.

8. The method of claim 7 wherein the color indicator comprises a circle of colors wherein velocity at the value of the maximum is a first color and other values of velocity have different colors.

9. The method of claim 8 wherein the first color is red.

10. A method for providing a quantitative color flow display of moving matter using an ultrasound imaging system, the display being formed of pixels on a display device, which method comprises the steps of:

transmitting acoustic beams to a region of interest in the body, which region of interest includes the moving matter;

receiving echo beams from the region of interest;

obtaining, at each portion of the region of interest, which portion is referred to as a pixel, a measure of velocity of moving matter in the pixel and a measure of direction of the velocity of the moving matter in the pixel;

determining a cross section of the moving matter from the measures of velocity of the moving matter in the pixels in the region of interest;

determining a maximum of the measures of velocity in the cross section;

displaying the measures of velocity and direction of the pixels of the cross section wherein the measures of direction are displayed using a color indicator which is relative to the direction of the maximum measure of velocity in the cross section and wherein the measures of velocity are displayed in intensity relative to the maximum measure of velocity.

11. The method of claim 10 wherein the color indicator comprises a circle of colors wherein a direction in the same direction as the maximum is a first color and other values of direction have different colors.

12. The method of claim 11 wherein the first color is red and a velocity in a direction opposite to the direction of the maximum velocity is blue.

13. A method for providing a quantitative color flow display of blood flow in a blood vessel using an ultrasound imaging apparatus, which method comprises the steps of:

transmitting an acoustic beam to a region of interest in the blood vessel from a first sub-aperture array in a transducer array;

receiving a first echo beam from the region of interest at the first sub-aperture array, which first echo beam is generated by the acoustic beam, and a second echo from the region of interest at a second sub-aperture array, which second echo beam is generated by the acoustic beam;

estimating a first mean Doppler frequency from the first echo beam in a color flow processor substantially in parallel with the step of estimating a second mean Doppler frequency from the second echo beam in a color processor;

estimating a blood flow angle and blood flow velocity in the region of interest in the blood vessel from the first and second mean Doppler frequencies;

converting the data to provide a blood flow velocity distribution; and

;

displaying (a) the blood flow velocity distribution in accordance with a color indicator and (b) displaying the color indicator so that it indicates the direction of the estimate of blood flow angle.

14. The method of claim 13 Wherein the color indicator is a color bar comprised of two colors, a first color for flow in the direction of the estimated angle and a second color for flow in the opposite direction.

15. The method of claim 14 wherein the color indicator is a color wheel having a line indicator of the direction.

16. The method of claim 13 which further comprises the step of displaying a warning when an estimate of blood flow angle, relative to the transmitted acoustic beam, exceeds a predetermined value.

17. The method of claim 16 wherein the warning comprises flashing the region of interest.

18. A method for providing a quantitative color flow display of blood in a blood vessel using an ultrasound imaging apparatus, which method comprises the steps of:

transmitting an acoustic beam to a region of interest in the blood vessel from a transducer array;

receiving a first echo beam from the region of interest at the transducer array, which first echo beam is generated by the acoustic beam, and a second echo from the region of interest at the transducer array, which second echo beam is generated by the acoustic beam;

estimating a first mean Doppler frequency from the first echo beam in a color flow processor substantially in parallel with the step of estimating a second mean Doppler frequency from the second echo beam in a color processor;

estimating a blood flow angle and blood flow velocity in the region of interest in the blood vessel from the first and second mean Doppler frequencies;

converting the data to provide a blood flow velocity distribution; and

;

displaying (a) the blood flow velocity distribution in accordance with a color indicator and (b) displaying the color indicator so that it indicates the direction of the estimate of blood flow angle.

19. The method of claim 18 wherein the steps of estimating comprise the steps of wall filtering and compensating the estimates for biasing which results from wall filtering.

20. A method for providing a quantitative color flow display of blood in a blood vessel using an ultrasound imaging apparatus, which method comprises the steps of:

transmitting an acoustic beam to a region of interest in the blood vessel from a transducer array;

receiving a first echo beam from the region of interest at the transducer array, which first echo beam is generated by the acoustic beam, and a second echo from the region of interest at the transducer array, which second echo beam is generated by the acoustic beam;

estimating a first mean Doppler frequency and a first power from the first echo beam in a color flow processor substantially in parallel with the step of estimating a second mean Doppler frequency and a second power from the second echo beam in a color processor;

estimating a blood flow angle in the region of interest in the blood vessel from the first and second mean Doppler frequencies;

determining the angle of the first echo beam and the second echo beam with respect to the estimated blood flow angle;

converting the data to provide color power distribution data selected from a predetermined one of the first power or second power;

utilizing the non-selected power whenever the angle of the selected one of the first power or second power was determined from an echo beam having an angle whose value is within a predetermined amount from 90°

; and

;

displaying the color power distribution data.

21. A method for providing a blood flow velocity distribution display of blood in a blood vessel using an ultrasound imaging apparatus, which method comprises the steps of:

transmitting an acoustic beam to a region of interest in the blood vessel from a first sub-aperture array in a transducer array;

receiving a first echo beam from the region of interest at the first subaperture array, which first echo beam is generated by the acoustic beam, and a second echo from the region of interest at a second sub-aperture array, which second echo beam is generated by the acoustic beam;

estimating a first mean Doppler frequency from the first echo beam in a color flow processor substantially in parallel with the step of estimating a second mean Doppler frequency from the second echo beam in a color flow processor;

estimating a first blood flow angle in the region of interest in the blood vessel from the first and second mean Doppler frequencies;

transmitting a second acoustic beam to a region of interest in the blood vessel from the second sub-aperture array;

receiving a third echo beam from the region of interest at the second sub-aperture array, which third echo beam is generated by the second acoustic beam;

estimating a third mean Doppler frequency from the third echo beam in a color flow processor;

estimating a second blood flow angle in the region of interest in the blood vessel from the first and third mean Doppler frequencies; and

comparing the first and second blood flow angles and displaying a warning if the values differ by more than a predetermined amount.

22. A method for providing a blood flow velocity distribution display of blood in a blood vessel using an ultrasound imaging apparatus, which method comprises the steps of:

transmitting an acoustic beam to a region of interest in the blood vessel from a transducer array;

receiving a first echo beam from the region of interest at a first sub-aperture array, which first echo beam is generated by the acoustic beam, and a second echo from the region of interest at a second sub-aperture array, which second echo beam is generated by the acoustic beam;

estimating a first mean Doppler frequency from the first echo beam in a color flow processor substantially in parallel with the step of estimating a second mean Doppler frequency from the second echo beam in a color flow processor;

estimating a blood flow and blood flow velocity in the region of interest in the blood vessel from the first and second mean Doppler frequencies;

converting the data to provide a blood flow velocity distribution; and

;

displaying (a) the blood flow velocity distribution in accordance with a color bar and (b) displaying the color bar so that it is oriented along the direction of the estimate of blood flow angle.

23. Ultrasound imaging system for providing a quantitative color flow display of moving matter, the display being formed of pixels on a display device, which system comprises:

means for transmitting acoustic beams to a region of interest in the body, which region of interest includes the moving matter, and for receiving echo beams from the region of interest;

means for obtaining, at each portion of the region of interest, which portion is referred to as a pixel, a measure of velocity of moving matter in the pixel and a measure of direction of the velocity of the moving matter in the pixel;

means for determining a maximum of the measure of velocity at each pixel in the region of interest over a predetermined period of time and the measure of direction of the maximum velocity; and

means for displaying the measures of velocity of the pixels for the predetermined period of time wherein the measures of velocity and the measure of direction of the velocity are displayed using a color indicator which is relative to the maximum measure of velocity at each pixel and to the measure of direction of the maximum velocity.