Ultrasound gray-scale imaging system and method

An ultrasound grayscale flow imaging method, comprising:

• transmitting, via a probe, multiple groups of non-focused ultrasound beams and focused ultrasound beams to a scanning target containing a flow, wherein the non-focused and focused ultrasound beams comprise only B-mode pulses;
• receiving echoes of the multiple non-focused ultrasound beams returned from the flow to obtain multiple groups of non-focused ultrasound echo signals and receiving echoes of the multiple focused ultrasound beams returned from the scanning target to obtain multiple groups of focused ultrasound echo signals;
• obtaining grayscale flow data according to the multiple groups of non-focused ultrasound echo signals using grayscale flow imaging without using Doppler processing;
• obtaining B-mode ultrasound image data according to the multiple groups of focused ultrasound echo signals;
• overlaying the grayscale flow data on the B-mode ultrasound image data to obtain a B-mode ultrasound image sequence by:
• calculating variances of I data and Q data demodulated from the grayscale flow data, wherein the variances are calculated according to the formula,
• V
• a
• ⁢
• r
• =
• (
• I
• i
• +
• 1
• ⁢
• I
• i
• +
• Q
• i
• +
• 1
• ⁢
• Q
• i
• )
• 2
• +
• (
• Q
• i
• +
• 1
• ⁢
• I
• i
• -
• I
• i
• +
• 1
• ⁢
• Q
• i
• )
• 2
• I
• i
• 2
• +
• Q
• i
• 2
• where i represents a sampling time, Ii represents I data at ith time, and Qi represents Q data at ith time;
• determining non-flow regions and flow regions based on a variance threshold;
• and
• mapping trends of the variances with grayscales and/or colors to obtain the B-mode ultrasound image sequence overlaid with the grayscales and/or colors or obtain the B-mode ultrasound image sequence overlaid with the grayscales and/or colors based on regions;
• and
• displaying the B-mode ultrasound image sequence.

An ultrasound grayscale flow imaging system, comprising:

• a probe;
• a transmitting circuit which excites the probe to transmit multiple groups of non-focused ultrasound beams and focused ultrasound beams to a scanning target containing a flow, wherein the non-focused ultrasound beams and focused ultrasound beams comprise only B-mode pulses;
• a receiving circuit which receives echoes of the multiple non-focused ultrasound beams returned from the flow to obtain multiple groups of non-focused ultrasound echo signals and receives echoes of the multiple focused ultrasound beams returned from the scanning target to obtain multiple groups of focused ultrasound echo signals;
• a signal processing unit which obtains grayscale flow data according to the multiple groups of non-focused ultrasound echo signals using grayscale flow imaging without using Doppler processing;
• a B-mode signal processing unit which obtains grayscale ultrasound image data according to the multiple groups of focused ultrasound echo signals;
• an image processing unit which overlays the grayscale flow data on the grayscale ultrasound image data and obtains a B-mode ultrasound image sequence according to the grayscale ultrasound image data overlaid with the grayscale flow data, wherein the image processing unit is further configured to:
• calculate variances of I data and Q data demodulated from the grayscale flow data, wherein the variances are calculated according to the formula,
• V
• a
• ⁢
• r
• =
• (
• ∑
• i
• =
• 0
• N
• ⁢
• I
• i
• +
• k
• ⁢
• I
• i
• +
• Q
• i
• +
• k
• ⁢
• Q
• i
• )
• 2
• +
• (
• ∑
• i
• =
• 0
• N
• ⁢
• Q
• i
• +
• k
• ⁢
• I
• i
• -
• I
• i
• +
• k
• ⁢
• Q
• i
• )
• 2
• R
• ⁡
• (
• 0
• )
• where K=0, 1, 2, 3 . . . R(0) represents energy of flow signals obtained using a Lag-zero method, which is represented by:
• R
• ⁡
• (
• 0
• )
• =
• ∑
• i
• =
• 0
• N
• ⁢
• I
• i
• 2
• +
• Q
• i
• 2
• +
• I
• i
• +
• k
• 2
• +
• Q
• i
• +
• k
• 2
• 2
• ⁢
• (
• N
• +
• 1
• )
• ;
• determine non-flow regions and flow regions based on a variance threshold;
• and
• map trends of the variances with grayscales and/or colors to obtain the B-mode ultrasound image sequence overlaid with the grayscales and/or colors or obtain the B-mode ultrasound image sequence overlaid with the grayscales and/or colors based on regions;
• and
• a display device which displays the B-mode ultrasound image sequence.