Ultrasound diagnosis apparatus to correct a saturation region in an ultrasound image

1 . An ultrasound diagnosis apparatus, comprising:

an ultrasound probe configured to transmit, to a subject, an ultrasound wave, and receive reflected-wave signals that are based on waves reflected from the subject;

protecting circuitry configured to limit the reflected-wave signals exceeding a predetermined range of amplitudes to within the predetermined range of amplitudes; and

processing circuitry configured to:

correct a saturated region represented by a signal limited to within the predetermined range of amplitudes in an odd-numbered order harmonic image obtained from odd-order harmonic components of the reflected wave signal that has passed through the protecting circuitry, by using an even-numbered order harmonic image obtained from even- order harmonic components of the reflected wave signal that has passed through the protecting circuitry, the even-numbered order harmonic image corresponding to the saturated region represented by the odd-numbered order harmonic image, and

output the corrected odd-numbered order harmonic image.

2 . The ultrasound diagnosis apparatus according to claim 1 , wherein

the processing circuitry is further configured to generate the odd-numbered order harmonic image based on the odd-numbered order harmonic component of the reflected-wave signals, and

the correcting by the processing circuitry includes replacing the saturated region with the corresponding region.

3 . The ultrasound diagnosis apparatus according to claim 1 , wherein an odd number indicating an order of the odd-numbered order harmonic image and an even number indicating an order of the even-numbered order harmonic image are consecutive natural numbers.

4 . The ultrasound diagnosis apparatus according to claim 1 , wherein the processing circuitry is further configured to:

generate a first histogram and a second histogram, the first histogram being a histogram of a brightness value of each pixel in the odd-numbered order harmonic image, the second histogram being a histogram of a brightness value of each pixel in the even-numbered order harmonic image, and

compare the first histogram to the second histogram to calculate a shift amount for an average of the brightness value of each pixel in the even-numbered order harmonic image that is necessary to match an average of the brightness value of each pixel in the odd-numbered order harmonic image for the first histogram with the average of the brightness value of each pixel on the even-numbered order harmonic image for the second histogram, and set the shift amount to a signal value offset for adjusting the corresponding region, and

the correcting by the processing circuitry includes replacing the saturated region included in the odd-numbered order harmonic image with an adjusted region in which the brightness value of each pixel in the corresponding region is offset with the signal value offset.

5 . The ultrasound diagnosis apparatus according to claim 4 , wherein the processing circuitry is further configured to:

calculate a standard deviation of the brightness value of each pixel in the odd-numbered order harmonic image and a standard deviation of the brightness value of each pixel in the even-numbered order harmonic image, and

calculate the average of the brightness value of each pixel in the odd-numbered order harmonic image by taking the standard deviation of the brightness value of each pixel in the odd-numbered order harmonic image into consideration, and calculate the average of the brightness value of each pixel in the even-numbered order harmonic image by taking the standard deviation of the brightness value of each pixel in the even-numbered order harmonic image into consideration.

6 . An image processing apparatus, comprising:

processing circuitry configured to:

correct a saturated region represented by a signal limited to within a predetermined range of amplitudes in an odd-numbered order harmonic image obtained from odd-order harmonic components of a reflected wave signal received by an ultrasound probe and has passed through protecting circuitry, by using an even-numbered order harmonic image obtained from even-order harmonic components of the reflected wave signal that has passed through the protecting circuitry, the even-numbered order harmonic image corresponding to the saturated region represented by the odd-numbered order harmonic image; and

output the corrected odd-numbered order harmonic image.

7 . A computer program product having a non-transitory computer-readable storage medium including programmed instructions, wherein the instructions, when executed by a computer included in an ultrasonic diagnosis apparatus, cause the computer to perform:

correcting a saturated region represented by a signal limited to within a predetermined range of amplitudes in an odd-numbered order harmonic image obtained from odd-order harmonic components of a reflected wave signal that has passed through protecting circuitry, by using an even-numbered order harmonic image obtained from even-order harmonic components of the reflected wave signal that has passed through the protecting circuitry, the even-numbered order harmonic image corresponding to the saturated region represented by the odd-numbered order harmonic image; and

outputting the corrected odd-numbered order harmonic image.

8 . The ultrasound diagnosis apparatus according to claim 1 , wherein the processing circuitry is further configured to generate, based on the reflected-wave signals received by the ultrasound probe, the odd-numbered order harmonic image and the even-numbered order harmonic image that represent a range of the subject to which the ultrasound wave has been transmitted.

9 . The ultrasound diagnosis apparatus according to claim 1 , wherein the ultrasound probe is configured to transmit, to the subject, the ultrasound wave multiple times corresponding to a plurality of different phases, and receive reflected-wave signals that are based on waves reflected from the subject.