JP4201396B2 - Ultrasonic diagnostic equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ultrasonic diagnostic apparatus that obtains and displays an ultrasonic image of a diagnostic site in a subject using ultrasonic waves, and in particular, a reflectance tomographic image and an elastic modulus image of a living tissue. The present invention relates to an ultrasonic diagnostic apparatus capable of displaying on the same screen.
[0002]
[Prior art]
A conventional ultrasonic diagnostic apparatus measures the ultrasonic reflectance of a living tissue in a subject using ultrasonic waves, and displays it as a luminance tomographic image of a diagnostic region. Further, in recent ultrasonic diagnostic apparatuses, it has been performed to measure the elastic modulus of a living tissue as a tissue property diagnosis and display it as a luminance image of the diagnostic region as luminance. This elastic modulus image is intended to be useful for diagnosis of a subject by measuring whether a living tissue at a diagnostic site is hard or soft.
[0003]
[Problems to be solved by the invention]
However, in the conventional ultrasonic diagnostic apparatus, the reflectance tomographic image and the elastic modulus image of the diagnostic region are displayed separately. That is, the elastic modulus image is not displayed when the reflectance tomographic image is displayed, and the reflectance tomographic image is not displayed when the elastic modulus image is displayed. In this case, since the reflectance tomogram is not displayed when the elastic modulus image is displayed, it is not possible to know which portion of the elastic modulus image inside the subject is being observed, and which portion of the subject is anatomical. It may be difficult to determine whether a living tissue is hard or soft, and may not be fully useful for diagnosis.
[0004]
Accordingly, the present invention addresses such problems and provides an ultrasonic diagnostic apparatus capable of displaying a reflectance tomographic image and an elastic modulus image of a living tissue on the same screen of an image display device. Objective.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, an ultrasonic diagnostic apparatus according to the present invention includes a probe that transmits and receives ultrasonic waves in a subject, and a vibration that receives a drive signal and vibrates to cause a pressure change to the subject. A generation means, a phasing means for receiving a reflected echo signal from the inside of the subject, performing delay processing and aligning and adding the phases, and inputting a phasing output signal from the phasing means; A discrimination circuit for discriminating between a reflectance measurement signal and an elasticity measurement signal for alternately measuring a reflectance tomogram and an elasticity image of a diagnostic region, and a reflectance tomogram or an elasticity image of the diagnostic region A transmission control circuit that generates a transmission timing according to the measurement mode, sends a drive signal to the vibration generating means and sends a control signal to the discrimination circuit, and a reflectance measurement signal from the discrimination circuit. Enter to demonstrate the ultrasound reflectance of living tissue The reflectance calculation circuit, the elasticity measurement circuit that inputs the elasticity measurement signal from the discrimination circuit and calculates the elasticity of the living tissue, and the calculation output signal from each of these calculation circuits And an image display device that displays the created image data as a reflectance tomographic image and an elastic modulus image of a diagnostic site in the subject, and when the vibration generating unit is not operating, The discrimination circuit discriminates the phasing output signal from the phasing means from the reflectance measurement signal and sends it to the reflectance calculation circuit. When the vibration generating means is operating, the discrimination circuit The phasing output signal from the signal is discriminated from the elastic modulus measurement signal and sent to the elastic modulus calculation circuit.
[0006]
The calculation of the elastic modulus of the upper Symbol biological tissues, elastic modulus image signal measured when entering the elastic modulus upon measuring phase gives a pressure change into a subject by driving the vibration generating means E ₂ (t) And the elastic modulus image signal E ₃ (t) measured in the elastic modulus measurement time phase after entering the elastic modulus measurement time phase, the change rate ΔE (t) between the two is obtained by the following equation: Seeking
ΔE (t) = {E ₂ (t) −E ₃ (t)} / E ₂ (t)
This rate of change ΔE (t) is the elastic modulus.
[0007]
Further, the reflectance tomographic image and the elastic modulus image displayed on the image display device create image data as the luminance of black and white display corresponding to the ultrasonic reflectance of the biological tissue, and color corresponding to the elastic modulus of the biological tissue. Image data may be created as the display luminance, and both images may be displayed on the same screen.
Furthermore, the reflectance tomographic image and the elastic modulus image displayed on the image display device have a constant ultrasonic scanning direction into the subject, and the ultrasonic reflectance and elastic modulus of the living tissue in the scanning line direction are calculated. You may make it measure and display with the brightness | luminance according to the ultrasonic reflectance with the passage of time, and the brightness | luminance according to an elasticity modulus.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a block diagram showing an embodiment of an ultrasonic diagnostic apparatus according to the present invention. This ultrasonic diagnostic apparatus obtains and displays an ultrasonic image of a diagnostic site in a subject using ultrasonic waves, and particularly displays a reflectance tomographic image and an elastic modulus image of a living tissue. As shown in FIG. 1, the probe 1, the transmission pulse generator 2, the transmission / reception separation circuit 3, the low frequency oscillator 4, the vibrator 5, and the transmission control circuit are displayed on the same screen. 6, a phasing circuit 7, a reflection / elastic modulus discrimination circuit 8, a reflectance calculation circuit 9, an elasticity calculation circuit 10, a scan converter 11, and an image display device 12.
[0009]
The probe 1 transmits and receives ultrasonic waves into the subject 13, and is omitted from the drawing, but includes a plurality of transducers that emit ultrasonic waves and receive reflected echoes. The transmission pulse generator 2 generates a transmission pulse signal for driving the probe 1 and transmitting ultrasonic waves. Further, the transmission / reception separating circuit 3 amplifies the transmission pulse signal from the transmission pulse generator 2 so that an ultrasonic wave can be transmitted from the probe 1, and gives the amplified signal to the probe 1, and then the signal. By switching the line, only the received signal from the probe 1 is sent to the phasing circuit 7 side.
[0010]
The low frequency oscillator 4 generates a low frequency signal in order to give a low frequency vibration to the subject 13. The vibrator 5 is a vibration generating unit that receives the low frequency signal generated by the low frequency oscillator 4 and vibrates to give a pressure change to the subject 13. The wave transmission control circuit 6 controls the wave transmission pulse generator 2 and the low frequency oscillator 4 according to the measurement mode of the reflectance tomographic image or the elastic modulus image of the diagnostic part in the subject 13. The timing of transmission is generated.
[0011]
The phasing circuit 7 serves as a phasing means that receives a reflected echo signal from the inside of the subject 13 and performs delay processing to align and add phases, and each of the vibrations of the probe 1 is included therein. It comprises a wave receiving amplifier for amplifying the reflected echo signal received by the child, a wave receiving delay circuit and an adder for forming the received ultrasonic beam by aligning the phases of the received reflected echo signals.
[0012]
The reflection / elastic modulus discriminating circuit 8 inputs the phasing output signal from the phasing circuit 7 and transmits it according to the measurement mode of the reflectance tomographic image or the elastic modulus image generated by the transmission control circuit 6. In accordance with the timing of the wave, the reflectance measurement signal and the elastic modulus measurement signal are discriminated. The reflectance calculation circuit 9 is a means for calculating the ultrasonic reflectance of the living tissue by inputting the reflectance measurement signal from the reflection / elasticity discrimination circuit 8. The elastic modulus calculation circuit 10 is a means for inputting the elastic modulus measurement signal from the reflection / elastic modulus discrimination circuit 8 and calculating the elastic modulus of the living tissue.
[0013]
The scan converter 11 serves as means for generating image data by inputting an ultrasonic reflectance or elastic modulus calculation output signal from the reflectance calculation circuit 9 or the elastic modulus calculation circuit 10. Further, the image display device 12 displays the image data from the scan converter 11 as an ultrasonic image, and is composed of, for example, a color television monitor.
[0014]
In the present invention, the operation of the reflection / elasticity discrimination circuit 8, the reflectance calculation circuit 9, and the elasticity calculation circuit 10 causes the reflectance tomographic image and the elasticity image of the diagnostic region in the subject 13 to be simultaneously displayed. Alternatively, measurements are taken alternately and these are displayed on the same screen of the image display device 12.
[0015]
Next, an operation of obtaining and displaying the reflectance tomographic image and the elastic modulus image of the diagnostic part in the ultrasonic diagnostic apparatus configured as described above will be described with reference to FIGS. First, as shown in FIG. 2, the transmission control circuit 6 shown in FIG. 1 transmits waves according to the reflectance measurement time phase for measuring the reflectance tomogram and the elasticity measurement time phase for measuring the elasticity image. Timings T ₁ , T ₂ , and T ₃ are generated. The generated transmission timings T ₁ , T ₂ and T ₃ are sent to the transmission pulse generator 2 and the low-frequency oscillator 4 to control their operations.
[0016]
First, at the transmission timing T ₁ , it is a reflectance measurement time phase, and the transmission pulse generator 2 generates, for example, a sine wave having a frequency of 3.5 MHz and three wave numbers in accordance with the timing T ₁ , and the transmission / reception separating circuit 3. A transmission pulse signal is supplied to the probe 1 via Thereby, the probe 1 is driven, ultrasonic waves are transmitted from the probe 1 into the subject 13, and a reflected echo signal is received. At this time, since the low-frequency oscillator 4 is not operating and no pressure change is applied to the subject 13, a normal reflectance tomogram (B mode image) is measured. The reflection / elastic modulus discrimination circuit 8 discriminates the phasing output signal from the phasing circuit 7 from the reflectance measurement signal, and sends the phasing output signal to the reflectance calculation circuit 9. In this case, the reflectance calculation circuit 9 performs signal processing of a normal reflectance tomogram and calculates the ultrasonic reflectance of the living tissue.
[0017]
Next, at the transmission timing T ₂ , the elastic modulus measurement time phase is entered, and the low frequency oscillator 4 sends an output signal as shown in FIG. 2 to the vibrator 5, which vibrates to generate the output signal. A pressure corresponding to the amplitude of is applied to the subject 13. Even in this state, the transmission pulse generator 2 supplies the transmission pulse signal to the probe 1 through the transmission / reception separation circuit 3. Thereby, an ultrasonic wave is transmitted from the probe 1 into the subject 13 and a reflected echo signal is received. At this time, since the measurement is performed in a state where a pressure change is applied to the subject 13, a mode for measuring an elastic modulus image is set. The reflection / elastic modulus discriminating circuit 8 discriminates the phasing output signal from the phasing circuit 7 from the elastic modulus measurement signal and sends the phasing output signal to the elastic modulus calculation circuit 10. In this case, the elastic modulus calculation circuit 10 performs signal processing of the elastic modulus image and stores the signal at that time as, for example, E ₂ (t).
[0018]
Next, at the wave transmission timing T _3, the elastic modulus measurement time phase continues, and similarly to the above, a pressure change is applied to the subject 13 by the vibrator 5 and the pressure change is applied by the probe 1. An ultrasonic wave is transmitted into the specimen 13 and a reflected echo signal is received. At this time, since the degree of change in position of the minute reflector inside the subject 13 that has undergone a pressure change varies depending on the difference in the elastic modulus of the living tissue, the amplitude of the reflected ultrasonic wave changes. At this time as well, the mode for measuring the elastic modulus image is set as described above. The reflection / elastic modulus discriminating circuit 8 discriminates the phasing output signal from the phasing circuit 7 from the elastic modulus measurement signal and sends the phasing output signal to the elastic modulus calculation circuit 10. In this case, the elastic modulus calculation circuit 10 performs signal processing of the elastic modulus image, and stores the signal at that time, for example, as E ₃ (t).
[0019]
The elastic modulus calculation circuit 10 calculates the change rate ΔE (t) from the two stored signals E ₂ (t) and E ₃ (t) by the following equation, and calculates the elastic modulus of the living tissue.
ΔE (t) = {E ₂ (t) −E ₃ (t)} / E ₂ (t)
This is output as the elastic modulus of the minute reflector inside the subject 13.
[0020]
The ultrasound reflectance signal of the biological tissue output from the reflectance calculation circuit 9 and the elasticity signal of the biological tissue output from the elasticity calculation circuit 10 are input to the scan converter 11, and the scan converter 11 Thus, the image data is created as the brightness of the monochrome display according to the ultrasonic reflectance of the living tissue, and the image data is created as the brightness of the color display according to the elastic modulus of the living tissue. By sequentially moving the scanning lines, image data is created for each scanning line.
[0021]
The image data created by the scan converter 11 is input to the image display device 12 and displayed. At this time, as shown in FIG. 3, the display screen of the image display device 12 is divided into, for example, left and right or up and down, and a reflectance obtained by imaging a part (organ) A of a living tissue having a high ultrasonic reflectance on one side. A tomographic image I ₁ is displayed, and an elastic modulus image I _{2 in} which a site (organ) B having a large elastic modulus of the living tissue is imaged is displayed on the other side. Thereby, the reflectance tomographic image I ₁ and the elastic modulus image I ₂ of the diagnostic region in the subject 13 can be displayed on the same screen of the image display device 12.
[0022]
In FIG. 2, the transmission timings T ₁ and T ₂ are set to different time phases. However, the transmission timings T ₁ and T ₂ may be set to the same time phase. In this case, the reflectance measurement time phase and the elasticity measurement time phase overlap, and the reflectance tomographic image I ₁ and the elasticity image I _{2 of} the diagnostic region can be simultaneously measured and displayed on the same screen. .
[0023]
FIG. 4 is an explanatory diagram showing another embodiment of displaying the reflectance tomographic image and the elastic modulus image on the image display device 12. In this embodiment, the reflectance tomographic image I ₁ and the elastic modulus image I ₂ displayed on the image display device 12 are generated as image data with the brightness of monochrome display corresponding to the ultrasonic reflectance of the living tissue, Image data is created as the luminance of color display according to the elastic modulus of the tissue, and both images are displayed on the same screen. For example, the reflectance tomographic image I ₁ obtained by imaging the part A of the biological tissue having a high ultrasonic reflectance is set to the luminance of black and white display corresponding to the ultrasonic reflectance, and the part B having a high elastic modulus of the biological tissue is imaged. Both images are displayed in an overlapping manner, with the elastic modulus image I ₂ as color display luminance corresponding to the elastic modulus. In this way, it is possible to understand at a glance which part of the inside of the subject 13 is observing the elastic modulus image I ₂ , and it is anatomically determined which part of the living tissue is hard or soft. It becomes easy.
[0024]
FIG. 5 is an explanatory diagram showing still another embodiment of displaying the reflectance tomographic image and the elastic modulus image on the image display device 12. In this embodiment, the ultrasonic scanning direction into the subject 13 is constant, the ultrasonic reflectance and elastic modulus of the living tissue in the direction of the scanning line 14 are measured, and the ultrasonic reflectance according to the passage of time is measured. Display with brightness corresponding to the brightness and elastic modulus. At this time, the operation of the scan converter 11 shown in FIG. 1 is changed to perform display similar to a normal M-mode image. That is, the direction of the scanning line 14 is fixed with respect to the diagnostic part in the subject 13, and for example, the depth of the diagnostic part is set to the vertical axis direction of the screen, the time axis is set to the horizontal axis direction, and the time axis is scrolled sequentially. Then, a part A having a high ultrasonic reflectance and a part B having a large elastic modulus in the depth direction of the diagnostic part are imaged and displayed on the same screen. In this case, the relationship between the site A having a high ultrasonic reflectance and the site B having a large elastic modulus in the depth direction of the diagnostic site can be understood.
[0025]
【The invention's effect】
Since the present invention is configured as described above, according to the first aspect of the present invention, a pressure change is applied to the subject by the vibration generating means, and the phasing output signal from the phasing means is input by the discrimination circuit. Then, the reflectance tomographic image and the elastic modulus image for alternately measuring the reflectance tomographic image and the elastic modulus image of the diagnostic part in the subject are discriminated into the reflectance tomographic image of the diagnostic part or The transmission control circuit that generates the transmission timing according to the elastic modulus image measurement mode sends a drive signal to the vibration generating means and sends a control signal to the discrimination circuit, and the vibration generating means is not operating. In this case, the discrimination circuit discriminates the phasing output signal from the phasing means from the reflectance measurement signal and sends it to the reflectance calculation circuit.When the vibration generating means is operating, the discrimination circuit is Elasticity of phasing output signal from phasing means It can be sent by discriminating the measurement signal to the modulus computation circuit. Thereby, the ultrasonic reflectance of the living tissue is calculated by the reflectance calculation circuit, the elastic modulus of the living tissue is calculated by the elasticity calculation circuit, and the reflectance tomography of the diagnostic region in the subject is displayed on the image display device. Images and elastic modulus images can be displayed. Therefore, it can be understood at a glance which part of the inside of the subject the elastic modulus image is being observed, which can be used for diagnosis.
[0026]
According to the invention of claim 2, the elastic modulus image signal E ₂ (t) measured when the elastic modulus measurement time phase is entered and the other elastic modulus after entering the elastic modulus measurement time phase From the elastic modulus image signal E ₃ (t) measured during the measurement time phase, the rate of change ΔE (t) between the two is obtained, and this rate of change ΔE (t) is calculated as the elasticity of the minute reflector inside the subject. Can be output as a rate .
[0027]
Further, according to the invention of claim 3, the reflectance tomographic image and the elastic modulus image displayed on the image display device create image data as the luminance of monochrome display according to the ultrasonic reflectance of the living tissue. Since the image data is created as the brightness of the color display according to the elastic modulus of the living tissue and both images are displayed on the same screen, the elastic modulus image of any part inside the subject is observed. It is easy to understand at a glance whether the living tissue is hard or soft.
Furthermore, according to the fourth aspect of the present invention, the reflectance tomographic image and the elastic modulus image displayed on the image display device have a constant ultrasonic scanning direction into the subject, and a living body in the scanning line direction. measuring an ultrasonic reflectivity and the elastic modulus of the tissue, since be displayed at a luminance corresponding to the luminance and the elastic modulus corresponding to the ultrasonic reflectance over time, the ultrasonic reflection in the depth direction of the diagnostic region The relationship between the part with a large modulus and the part with a large elastic modulus can be understood.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an embodiment of an ultrasonic diagnostic apparatus according to the present invention.
FIG. 2 is an explanatory diagram showing a state in which a transmission timing is generated according to a reflectance measurement time phase and an elastic modulus measurement time phase by the transmission control circuit of the ultrasonic diagnostic apparatus.
FIG. 3 is an explanatory diagram showing a reflectance tomographic image and an elastic modulus image of a diagnostic region displayed on the same screen of the image display device.
FIG. 4 is an explanatory diagram showing another embodiment of displaying a reflectance tomographic image and an elastic modulus image on the image display device.
FIG. 5 is an explanatory diagram showing still another embodiment of displaying the reflectance tomographic image and the elastic modulus image on the image display device.
[Explanation of symbols]
1 ... Probe 1
2 ... Transmission pulse generator 3 ... Transmission / reception separation circuit 4 ... Low frequency oscillator 5 ... Vibrator 6 ... Transmission control circuit 7 ... Phase adjustment circuit 8 ... Reflection / elasticity discrimination circuit 9 ... Reflectance calculation circuit 10 ... Elasticity calculation Circuit 11 ... Scan converter 12 ... Image display device 13 ... Subject 14 ... Scanning line A ... Site with high reflectivity B ... Site with high elastic modulus

Claims (4)

A probe that transmits and receives ultrasound within the subject;
Vibration generating means for inputting a driving signal and vibrating to give a pressure change to the subject;
Phasing means for receiving reflected echo signals from within the subject and performing delay processing to align the phases and add;
By inputting the phasing output signal from the phasing means, the reflectance measurement signal and the elasticity measurement signal for alternately measuring the reflectance tomographic image and the elasticity image of the diagnostic region in the subject A discrimination circuit for discrimination;
A transmission control circuit that generates a transmission timing in accordance with a measurement mode of the reflectance tomogram or elasticity image of the diagnostic region, sends a drive signal to the vibration generating means, and sends a control signal to the discrimination circuit; ,
A reflectance calculation circuit that inputs the reflectance measurement signal from the discrimination circuit and calculates the ultrasonic reflectance of the living tissue;
An elastic modulus calculation circuit for calculating an elastic modulus of a living tissue by inputting an elastic modulus measurement signal from the discrimination circuit;
Means for inputting the calculation output signal from each of these calculation circuits and creating image data;
An image display device that displays the created image data as a reflectance tomographic image and an elastic modulus image of a diagnostic site in the subject;
When the vibration generating means is not operating, the discrimination circuit discriminates the phasing output signal from the phasing means from the reflectance measurement signal and sends it to the reflectance calculation circuit, and the vibration generating means operates. If so, the discrimination circuit discriminates the phasing output signal from the phasing means from the elastic modulus measurement signal and sends it to the elastic modulus calculation circuit. Calculation of the elastic modulus of the biological tissues, the elastic modulus image signal measured when entering the elastic modulus upon measuring phase gives a pressure change into a subject by driving the vibration generating means E ₂ (t), the From the elastic modulus image signal E ₃ (t) measured during the elastic modulus measurement time phase after entering the elastic modulus measurement time phase, the change rate ΔE (t) between the two is obtained by the following equation:
ΔE (t) = {E ₂ (t) −E ₃ (t)} / E ₂ (t)
The ultrasonic diagnostic apparatus according to claim 1 wherein the rate of change ΔE (t) is characterized in that the elastic modulus. The reflectance tomographic image and the elastic modulus image displayed on the image display device create image data as the luminance of the monochrome display corresponding to the ultrasonic reflectance of the biological tissue, and display the color display corresponding to the elastic modulus of the biological tissue. create an image data as luminance ultrasonic diagnostic apparatus according to claim 1, wherein the display overlapping both images at the same screen. The reflectance tomographic image and the elastic modulus image displayed on the image display device measure the ultrasonic reflectance and elastic modulus of the living tissue in the scanning line direction with the ultrasonic scanning direction into the subject constant. the ultrasonic diagnostic apparatus according to claim 1, wherein the display at a luminance corresponding to the luminance and the elastic modulus corresponding to the ultrasonic reflectivity over time.

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