JPH0775638A - Ultrasonic diagnostic device - Google Patents

Abstract

PURPOSE:To provide the ultrasonic diagnostic device which can prevent a fact that a contrast-medium component of a received signal projects from a dynamic range and saturated. CONSTITUTION:This ultrasonic diagnostic device is provided with a probe 1, a transmitting part 200, a receiving part 201, a signal processing part 202, a converting part 203, a display part 204, a control part 205 and a setting part 206. By the converting part 203, an ultrasonic image having a prescribed dynamic range obtained from an examinee to whom a contrast-medium is injected is converted to an ultrasonic image having a dynamic range corresponding to a dynamic range of the display part 204.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic diagnostic apparatus applied to diagnosis by an ultrasonic contrast agent.

[0002]

2. Description of the Related Art An ultrasonic diagnostic apparatus emits an ultrasonic pulse into a living body and receives a reflected wave reflected from a boundary surface of tissues having different specific acoustic impedances (the product of the density of both media and the sound velocity). After that, this is processed to obtain an image, which is a clinically useful device without exposure damage such as the X-ray diagnostic method. Moreover, real-time performance has improved due to the progress of various technologies typified by electronic scanning technology, and moving object measurement has become easier.

By the way, in recent years, development of ultrasonic contrast agents has progressed, and expectations for a detailed blood flow diagnosis comparable to X-ray angio are increasing. This ultrasonic contrast agent has the property of being distinctly different from the received signal from the living body in its intensity. As a result, the portion of the B-mode image into which the ultrasonic contrast agent has flowed differs in brightness or gradation level from the other portions, so that the observer can observe how the ultrasonic contrast agent has flowed in.

By the way, the accuracy is very low only by visually observing the inflow state of the ultrasonic contrast agent. In order to improve the diagnostic accuracy, it is necessary to obtain various kinds of information such as the change over time of the inflow / outflow amount of the contrast agent into the region of interest and its rise time. The conventional ultrasonic diagnostic apparatus cannot provide such various information, and therefore the observer measures the total concentration in the region of interest for each frame and summarizes the result in a graph for diagnosis. It was Thus, the observer is required to take uncomfortable labor and time to obtain various information. There is also a problem that the information cannot be obtained in real time. Furthermore, since the received signal contains a biological component and a contrast agent component, it is necessary to extract the contrast agent component from the received signal in order to accurately measure the inflow / outflow amount into / from the region of interest. Sound waves are more susceptible to movements than X-rays, and even if they are biological components of the same living body, their intensities are unstable over time, so it is possible to accurately extract the contrast agent component from the received signal. There is also the problem that it cannot be done.

Further, in general, the dynamic range of an ultrasonic diagnostic apparatus is set to an expected intensity range of a received signal from a living tissue in order to enhance contrast. For this reason, the contrast agent component of the received signal is clearly different from the received signal from the living body in its intensity, so that it may project from this dynamic range and become saturated, and there is also a problem that it cannot be imaged.

Furthermore, it is effective to simultaneously observe the inflow state of the contrast medium in two distant portions, for example, two portions of the carotid artery and the internal vein. Therefore, conventionally, two ultrasonic diagnostic apparatuses have been used. However, there is a problem that beat noise occurs in the image due to the influence of the ultrasonic waves of the other side. In addition, since images are generated separately between the two devices, the standard signal levels of the two devices differ due to differences in the electrical / ultrasonic conversion characteristics of the probes of the two devices and the gain characteristics of the preamplifier, etc. Therefore, comparison between images is not possible. There is also a problem.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to
An object of the present invention is to provide an ultrasonic diagnostic apparatus capable of preventing the contrast agent component of a received signal from protruding from the dynamic range and being saturated. Another object of the present invention is to provide an ultrasonic diagnostic apparatus capable of providing various kinds of information in real time, such as changes with time of the inflow / outflow amount of the contrast agent into the region of interest.

Still another object of the present invention is to provide an ultrasonic diagnostic apparatus capable of collecting images of two distant portions in real time while suppressing the generation of beat noise due to the influence of the ultrasonic waves of the other one.

[0009]

The above object can be achieved by the following ultrasonic diagnostic apparatus. That is, the present invention is a transmission / reception unit that transmits / receives ultrasonic waves to / from an object to obtain an ultrasonic reception signal, and an ultrasonic image having a predetermined dynamic range by signal processing the ultrasonic reception signal obtained by the transmission / reception unit. And a conversion unit for converting an ultrasonic image having a predetermined dynamic range obtained by the signal processing unit into an ultrasonic image having a dynamic range different from the predetermined dynamic range, and the conversion unit. An ultrasonic diagnostic apparatus, comprising: a display unit that displays an ultrasonic image obtained by the unit.

Further, according to the present invention, a plurality of ultrasonic probes for transmitting and receiving ultrasonic waves to and from different parts of a subject, and a frame composed of a plurality of scanning lines for driving the plurality of ultrasonic probes for transmission and reception. One transmitting / receiving unit for obtaining a unit ultrasonic image, a switching unit for switching a combination of connection between each ultrasonic probe of the plurality of ultrasonic probes and the transmitting / receiving unit in a time division manner, and an ultrasonic image for each frame unit A setting unit that sets a region of interest, and a calculation unit that obtains a time-division change curve of image data in the region of interest of the ultrasonic image in frame units set by the setting unit at substantially the same time,
An ultrasonic diagnostic apparatus, comprising: a display unit that simultaneously displays the plurality of temporal change curves obtained by the calculation unit.

Further, according to the present invention, a transmitting / receiving unit for transmitting / receiving ultrasonic waves to / from an object to obtain an ultrasonic wave reception signal, and a signal processing for signal-processing the ultrasonic wave reception signal obtained by the transmitting / receiving unit to obtain an ultrasonic image. Section, setting means for setting a region of interest in an ultrasonic image obtained by the signal processing part, means for obtaining a time-divisional change curve of image data in the region of interest set by the setting means at substantially the same time, An ultrasonic diagnostic apparatus comprising: an ultrasonic image obtained by the signal processing unit and a display unit that simultaneously displays the plurality of temporal change curves obtained by the means.

Furthermore, the present invention further provides a transmission / reception unit for transmitting / receiving ultrasonic waves to / from a subject to obtain an ultrasonic reception signal, and an ultrasonic image in frame units by signal processing the ultrasonic reception signal obtained by the transmission / reception unit. , A setting unit for setting a region of interest in a frame-based ultrasonic image obtained by the signal processing unit, and a filtering unit for performing filtering between regions of interest set for each frame by the setting unit A calculating section for obtaining a temporal change curve of image data in the ROI based on the image data of the ROI for each frame filtered by the filtering section; and the temporal change curve obtained by the calculating section. An ultrasonic diagnostic apparatus, comprising: a display unit for displaying.

[0013]

According to the present invention, an ultrasonic image having a desired dynamic range can be obtained. Therefore, even an ultrasonic image obtained from a subject injected with a contrast agent can be displayed on the display unit without being saturated. Therefore, it is possible to prevent the contrast agent component of the received signal from protruding from the dynamic range and being saturated.

Further, according to the present invention, a plurality of ultrasonic probes are time-divisionally transmitted / received by one transmission / reception unit,
The time-varying curves of a plurality of regions of interest can be simultaneously displayed without being affected by ultrasonic waves emitted from other ultrasonic probes and under the same transmission / reception conditions. Therefore, it is possible to present various kinds of information in real time, such as a temporal change in the inflow / outflow amount of the contrast agent into the region of interest.

Further, according to the present invention, it is possible to simultaneously obtain and display a plurality of time-varying curves in a plurality of regions of interest within one ultrasonic image. Therefore, the images of the two distant portions can be acquired in real time while suppressing the generation of beat noise due to the influence of the ultrasonic waves of the other.
Furthermore, based on the image data of the region of interest filtered between frames, it is possible to display a temporal change curve of the image data in the region of interest.

[0016]

Embodiments of the ultrasonic diagnostic apparatus according to the present invention will be described below with reference to the drawings. 1 is a block diagram showing a first embodiment of an ultrasonic diagnostic apparatus according to the present invention. As shown in FIG. 1, the ultrasonic probe 1 applied to the subject P
Are transmitted and received by the transmission unit 200 and the reception unit 201. An ultrasonic reception signal is obtained from the reception unit 201.
This ultrasonic reception signal is given to the signal processing unit 202, where an ultrasonic image such as a B-mode image, a Doppler image, or a CFM (color flow mapping) image is obtained. Converter 203
Converts the dynamic range of the ultrasonic image output from the signal processing unit 202. The display unit 204 displays the ultrasonic image having the converted dynamic range.
The control unit 205 controls the transmission unit 200, the reception unit 201, the signal processing unit 202, the conversion unit 203, and the display unit 204.

The setting unit 206 sets diagnostic conditions including the setting of ultrasonic conditions. In addition to this, the setting unit 206 responds to the ultrasound image from the subject in which the contrast agent is injected in the contrast agent mode and the ultrasound image from the subject in which the contrast agent is not injected in the normal mode. Conversion unit 203
The control unit 205 is instructed to change the conversion characteristic of the. The conversion unit 203 can obtain an ultrasonic image having good contrast in the normal mode by appropriately using the two log compressors having different dynamic ranges in the normal mode and the contrast agent mode. In contrast agent mode, the ultrasonic image can be log-compressed without saturating the signal of the contrast agent.

FIG. 2 shows a second ultrasonic diagnostic apparatus according to the present invention.
It is a block diagram which shows an Example. As shown in FIG. 2, the ultrasonic diagnostic apparatus of the second embodiment has a conversion unit 207 different from that of the ultrasonic diagnostic apparatus of the first embodiment. This conversion unit 20
The conversion unit 207 includes a memory 207A that stores one log compression curve data, a memory 207B that stores another log compression curve data, and a calculation unit 207C. For example, one log compression curve data is the log compression characteristic used in the normal mode, and the other log compression curve data is the log compression characteristic used in the contrast agent mode. The conversion unit 207 converts the input value into a predetermined output location based on the log compression curve data. Therefore, this conversion unit 20
Reference numeral 7 is for log-compressing the input value and outputting the log-compressed value. Even in the conversion unit 207, an ultrasonic image having a good contrast can be obtained in the normal mode by appropriately and selectively used in the normal mode and the contrast agent mode, and a signal of the contrast agent in the contrast agent mode can be obtained. The ultrasonic image can be log-compressed without being saturated.

FIG. 3 shows a third ultrasonic diagnostic apparatus according to the present invention.
It is a block diagram which shows an Example. The sector type electronic scanning type probe 1 is composed of a plurality of transducers arranged one-dimensionally. The probe 1 is not limited to the sector type electronic scanning type, and may be a linear type or a mechanical scanning type. A transmission system 2 is connected to the probe 1. The transmission system 2 is the probe 1
A drive pulse is supplied to each transducer of. The transmission system 2 makes the output timing of the drive pulse different between the transducers, and thereby transmits the ultrasonic beam in an arbitrary direction.

The reflected wave from the subject P is received by the same oscillator as when transmitting, and the received signal is supplied to the receiving system 3.
The receiving system 3 gives each reception signal a delay time opposite to that at the time of transmission and adds them. Two systems of log compressors 4 and 5 are connected to the output of the reception system 3. The first log compressor 4 is activated in the normal mode, and the second log compressor 5 is activated in the contrast agent mode. The log compressors 4 and 5 subject the output of the receiving system 3 to log compression according to the following equation (1), and output the result as luminance information. Note that θ is a log compressor output, I is a log compressor input, A is a predetermined coefficient, and DR is a parameter that determines the compression rate.

Θ = A · log DR · I (1) This parameter DR differs between the first log compressor 4 and the second log compressor 5. The first log compressor 4 uses the parameter DR1 or DR2 (DR1 <DR2). The second log compressor 5 uses DR3 which is larger than the parameter DR2. The input range to the log compressors 4 and 5 is Imin to Ima.
x, and its output range is fixed at θ min to θ max. Therefore, the log compression result is output range θmi.
When n is smaller or larger than θmax, the outputs are unified into Imin and Imax, respectively. FIG. 5 is a diagram showing logarithmic curves a, b, c corresponding to the parameters DR1, DR2, DR3 and respective dynamic ranges. The dynamic range for the parameter DR1 is I0 to Ia, the dynamic range for the parameter DR2 is I0 to Ib, and the dynamic range for the parameter DR1 is I0 to Imax.

Therefore, the dynamic range of the second log compressor 5 is wider than that of the first log compressor 4, so that the signal of the contrast agent can be log-compressed without being saturated. The output of the first log compressor 4 is supplied to the first frame memory 6, expanded on a two-dimensional matrix, and then arranged and output in one dimension in a predetermined order. This output is supplied to the display 8 via the ROI marker adder 7.

The output of the second log compressor 5 is supplied to the second frame memory 9, is developed into a two-dimensional matrix, and is arranged and output in a one-dimensional manner in a predetermined order. This output is sent to the contrast agent signal detection unit 10. The contrast agent signal detection unit 10 extracts a contrast agent component (hereinafter referred to as “contrast agent signal”) from the output of the second frame memory 9. This contrast agent signal is supplied to the display 8 via the two-dimensional contrast agent signal memory 11.

This contrast agent signal is also supplied to the graph calculation section 12. The graph calculation unit 12 uses the contrast agent signal to
A time-dependent change curve of the inflow / outflow amount of the contrast agent into / from the region of interest (ROI) (hereinafter referred to as “time density curve”)
Graph information is created and various time information such as inflow and outflow time is measured. The output of the graph calculator 12 is supplied to the display 8 via the two-dimensional graph information memory 13.

The controller 14 is connected via the bus line 15 to
A control signal and necessary information for each of the log compressors 4, 5, the frame memories 6, 9, the ROI marker adder 7, the contrast agent signal detection unit 10, the contrast agent signal memory 11, the graph calculation unit 12, and the graph information memory 13. Is supplied, the respective parts are associated and operated, and the processing of each part is executed.

The contrast medium mode input unit 16 is a device for inputting an instruction to switch between the normal mode and the contrast medium mode. The switching between the normal mode and the contrast agent mode may be performed depending on the key operation of the keyboard or may be performed depending on the output of the switch that detects activation of the contrast agent injection device. The contrast agent injection device
As shown in FIG. 4, the main component is a syringe composed of a cylindrical portion 20 having a projecting opening at one end and an insertion opening at the other end, and an insertion portion 21 inserted therein. When injecting a contrast agent using the contrast agent injecting device, the insertion section 21 is inserted into the cylindrical section 2
The tube 23 is inserted deep into the 0 or is connected to the projecting port via the joint 22. Therefore, it is possible to detect the activation of the contrast agent injection device by providing the joint 22 with the electrode switch 24 that detects that the tube 23 is connected to the projecting port or by providing the electromagnetic switch 25 with the syringe. . The electrode switch 24 is turned on when the tube 23 is connected to the protruding port.
Output a signal. The electromagnetic switch 25 includes a magnet provided near the tip of the insertion portion 21 and a coil provided in the cylindrical portion 20 that faces the magnet when the insertion portion 21 is deeply inserted into the cylindrical portion 20. Generates an induced current generated in the coil when the is inserted deep into the cylindrical portion 20,
The activation of the contrast agent injection device is detected, and an ON signal is output. Upon receiving the ON signal, the controller 14 switches the operation mode from the normal mode to the contrast agent mode.

FIG. 6 is a block diagram showing the configuration of the ROI marker adder 7. Marker information is supplied from the controller 14 to the ROI marker generator 41. The marker information is input by an observer operating an input device such as a mouse (not shown) connected to the controller 14. The ROI marker generator 41 outputs, for example, rectangular marker data indicating a region of interest based on the marker information. This marker data is supplied to the adder 43 via the switch 42 and
Is combined with the image from the memory 6. The switch 42 opens and closes according to a control signal from the controller 14, and the marker data based on the marker information is ROI marker generator 41.
The ROI marker generator 41 is connected to the adder 43 when output from the. The output of the adder 43 is supplied to the display 8.

FIG. 7 is a block diagram showing the configuration of the contrast agent signal detector 10. The region of interest (RO
The image in (I) (hereinafter referred to as "ROI image") is output, and this ROI image is supplied to the subtractor 57 as it is, and the subtractor 57 is also passed through the average value calculator 51 and the ROI frame average value memory 56. 57. The subtraction result of the subtractor 57 is the frame difference value, that is, the contrast addition signal, and the cumulative addition calculation unit 60 and the frame difference value memory 6
3 is supplied. The outputs of the cumulative addition calculation unit 60 and the frame difference value memory 63 are alternatively supplied to the contrast agent signal memory 11 and the graph calculation unit 12 via the switch 64.
The average value calculation unit 51 determines a region of interest (RO
I) is a means for calculating the average value of each pixel,
Adder 52, ROI frame memory 53, switch 5
4, a divider 55 is provided. In the adder 52, the ROI image input from the second memory 9 and the addition image input from the ROI frame memory 53 via the switch 54 are added pixel by pixel, and the addition image is added to the ROI frame memory 5
Supply to 3. The switch 54 switches the RO of a predetermined number of frames.
ROI frame memory 53 until the addition of I images is completed
Is connected to the adder 52, so that a predetermined number of frames of R
The OI images are added. This added image is divided by the number of added frames by the divider 55, and the averaged image is provided. Here, the averaging process is performed in order to reduce temporal fluctuations of the contrast agent signal and remove spike-like noise components. This average image is sent to the subtractor 57 via the ROI frame average value memory 56, the polarity is inverted by the −1 multiplier 57, and then the ROI image and the pixel from the second memory 9 are added by the adder 59. It is added every time. As a result, the contrast agent signal included in the ROI image is detected for each pixel, and the contrast agent image is generated. This contrast agent image is supplied to the cumulative addition calculation unit 60 and the frame difference value memory 63. The cumulative addition calculation unit 60 includes a frame difference value memory 63 feedback-connected to the adder 61, and cumulatively adds the contrast agent image for each pixel. The outputs of the cumulative addition calculation unit 60 and the frame difference value memory 63 are selectively read by the switching of the switch 64 and supplied to the contrast agent signal memory 11 and the graph calculation unit 12. The switching operation of the switch 64 is performed according to a display switching instruction input by an observer through an input device (not shown). The output of the contrast agent signal memory 11 is supplied to the display 8.

FIG. 8 is a block diagram showing the configuration of the graph calculator 12. The output of the contrast agent signal detector 10 is supplied to the sum value computing unit 71. The sum value calculation unit 71 causes the adder 72 connected to the output of the contrast agent signal detector 10 to output the first R
The OI pixel sum total value memory 73 is feedback-connected via the switch 74, and the contrast agent signals of all pixels in the ROI are added to obtain the sum total value D.

The max hold unit 75 detects the maximum value Dmax and the frame number FNmax of the plurality of total sum values D sequentially output from the total sum value calculation unit 71, and temporarily stores them. The latest sum total value D from the sum total value calculation unit 71 is inverted in polarity via the switch 76 and the −1 multiplier 77 and sent to the adder 78 and the memory 79. In the adder 78, the latest sum total value D is added from the memory 79 via the −1 multiplier 80 to the past sum total value D whose polarity is inverted again. The AND gate 81 logically judges the polarity of the output of the adder 78, that is, the magnitude relationship between the latest total sum value D and the past total sum value D, and outputs the judgment result to the memory 79 as update control of the memory 79. According to this determination result, the memory 79 stores the latest total sum value D instead of the past total sum value D when the latest total sum value D is larger than the past total sum value D. Therefore, the memory 79 always stores the maximum value Dmax of the plurality of total sum values D supplied to date. The determination result of the AND gate 81 is also supplied to the other memory 82, and according to the determination result,
By updating the frame number FN stored in the memory 82, the frame number FNmax corresponding to the maximum value Dmax stored in the memory 79 is stored. The frame number FN corresponding to the latest sum total value D is supplied from the controller 14 to the memory 82.

The maximum value Dmax is supplied to the multiplier 83 of the threshold value generator 83. The multiplier 83 receives the maximum value Dma
x is multiplied by a threshold coefficient K (usually 1/2) supplied from the controller 14, and a threshold value Dth is output. This threshold value Dth is sent to the time measuring unit 84.

The time measuring section 84 stores a second plurality of consecutive sum values D output from the sum value computing section 71.
An OI pixel sum value memory 85 is provided. Second RO
The I-pixel total value memory 85 sequentially outputs the total value D according to the input order. The output of the second ROI pixel sum value memory 85 is inverted in polarity via the −1 multiplier 86 and supplied to the adder 86, where it is added to the threshold value Dth. The result of this addition is sent to the AND gate 89, and its positive / negative is logically judged. As a result of this determination, when the total value D is larger than the threshold value Dth, the counter 90 is set to 1
Each is counted up. The counter 90 separately counts before and after the frame number FNmax under the control of the controller 14. This makes counter 9
At 0, the number of frames having the total value D equal to or greater than the threshold value Dth up to the frame having the maximum value Dmax and the maximum value Dma
The number of frames having a sum value D equal to or greater than the threshold value Dth after the frame of x is counted. The number of each frame is separately multiplied by the multiplier 91 with the frame cycle time Ft at the time of transmitting and receiving ultrasonic waves supplied from the controller 14 and converted into a real time. Inflow time twi, which indicates the time required for the contrast agent to flow into the ROI, in real time based on the former number of frames,
In the latter case, the actual time based on the number of frames is referred to as the outflow time tw0 indicating the time required for the contrast agent to flow out from the ROI, and the total time of the inflow time tw and the outflow time tw0 is referred to as the half width time th. The inflow time twi, the outflow time tw0, and the half width time t h are output to the graphic generator 93 via the measurement time memory 92.

The graphic generator 77 sequentially inputs the total sum value D from the total sum value calculation unit 71, plots points along the time axis according to the total sum value D, and gradually completes the time density curve. Go. This time density curve is output to the display unit 13 each time it is plotted even if it is incomplete. Therefore, the time density curve gradually grows on the display 13 in real time, and the time is nearing completion.

Next, the operation of this embodiment will be described.
First, the normal mode is activated. Under this normal mode,
The first log compressor 4 is activated. An ultrasonic beam from the probe 1 is generated by the drive signal from the transmitter 2
Section is repeatedly scanned. The reflected wave is probe 1
The received signal is sequentially output to the first log compressor 4 via the receiver 3. The first log compressor 4 log-compresses the received signal using the parameter DR1 or DR2 as described above, and supplies the result to the first frame memory 6. Therefore, the received signal of the biological tissue is optimally log-compressed with respect to the output range, and an image with good contrast is obtained. In this normal mode, the switch 43 of the ROI marker adder 7 is set to the OFF state.
Therefore, the image in the first frame memory 6 is as shown in FIG.
As shown in (a), it is displayed on the display 8 as it is.

The operator can switch from the normal mode to the contrast agent mode at any timing. This switching is
As described above, this is performed depending on the key operation of the keyboard on the contrast agent mode input unit 16 or the output of the switch that detects activation of the contrast agent injection device. It should be noted that even when the normal mode is switched to the contrast agent mode, the ultrasonic scanning is still continued in the same manner. Before and after the setting of the contrast agent mode, the switch 4 of the ROI marker adding device 7
3 is set to the ON state, and the ROI (broken line) is superimposed and displayed on the image as shown in FIG. 9B in accordance with the marker data from the ROI marker generator 41. This ROI is set at an arbitrary position by the operator. In this contrast agent mode, the second log compressor 5 is operated instead of the first log compressor 4. As described above, the second log compressor 5 uses the parameter DR1 of the first log compressor 4 or
The received signal is log-compressed using DR3, which is larger than DR2. Therefore, the dynamic range of the second log compressor 5 is wider than that of the first log compressor 4, so that the contrast agent signal having a higher signal level than the biological tissue can be log-compressed without being saturated.

The output of the second log compressor 5 is supplied to the second frame memory 5. Only the image within the ROI is selectively read from the second frame memory 5 and supplied to the contrast agent signal detection unit 10. This ROI image is supplied to the subtractor 57 and the average value calculator 51 of the contrast agent signal detector 10. The switch 52 of the average value calculator 51 is connected to the adder 52 side until a predetermined number of frames of ROI images are input. Therefore, the ROI frame memory 53
In addition, ROI images for a predetermined number of frames including the ROI image of the latest frame are added for each pixel. The outline of this addition processing is shown in FIG. When this addition is completed, the switch 52 is connected to the divider 55 side, and the addition result is supplied to the divider 55. The divider 55 divides this added image by the number of added frames and provides the average processing to reduce the temporal fluctuation of the contrast agent signal, remove spike-like noise components, and calculate this average image. It is supplied to the subtractor 57 via the ROI frame average value memory 56.
The subtractor 57 subtracts the average image from the ROI image of the latest frame. Each pixel of the ROI image before subtraction contains a biological tissue component and a contrast agent component. Since this biological tissue component does not change with time, the biological tissue component and the contrast agent component up to the previous frame are removed by subtracting the average image from the ROI image of the latest frame, and the change amount of the contrast agent component with respect to the previous frame. Is detected for each pixel, and a contrast agent image is generated. Focusing on a pixel in the contrast agent image, its value changes with time as shown in FIG. The contrast agent image is supplied to and stored in the frame difference value memory 63. The contrast agent image is also supplied to the cumulative addition calculation unit 60, and the contrast agent images that are sequentially supplied are sequentially cumulatively added pixel by pixel. Focusing on a pixel in the cumulatively added image obtained by the cumulative addition, its value is shown in FIG.
It changes with time as shown in (b). That is, this cumulative addition result corresponds to the total amount of the contrast agent currently present in the ROI. Frame difference value memory 63
The cumulative addition calculation unit 60 is alternatively connected to the contrast agent signal memory 11 and the graph calculation unit 12 via the switch 64. The switching of the switch 64 is performed according to an instruction from the operator. Normally, the switch 64 is connected to the cumulative addition calculation unit 60. Each time a contrast agent image is input, the cumulative addition calculation unit 60 outputs cumulative addition images one after another. The cumulative addition image is displayed on the display 8 while being sequentially switched via the contrast agent signal memory 11.
FIG. 12A to FIG. 12D are views showing the display screen along with the passage of time. The image (B mode image) is displayed in the left frame of each display screen, the cumulative addition image is displayed in the upper right frame of each display screen, and the time density curve is displayed in the lower right frame of each display screen. Since the cumulative addition image is output one after another every time the contrast agent image is input, the inflow state of the contrast agent is displayed in real time as shown in FIGS. 12 (a) to 12 (d).

Further, the cumulative addition image is sequentially sent to the graph calculation section 12, and the total sum value calculation section 71 sequentially calculates the total sum value D of all the pixels. The sum total value D of each frame is sequentially calculated by the max hold unit 75, the time measuring unit 84,
It is supplied to the graphic generator 93. At this time, the switch 76 of the max-hold unit 75 is set to the ON state, and the memory 79 sequentially updates and stores a value larger than the sum total value D up to all frames, whereby the sum total value D up to the current latest frame is always stored. The maximum value Dmax is stored,
The frame number F of the maximum value Dmax is stored in the memory 82.
Nmax is stored. The second ROI pixel sum value memory 85 of the time measuring unit 84 stores all sum values D up to the current latest frame. Graphic generator 9
In 3, the time density curve is gradually created in real time based on the total sum value D supplied one after another. The time density curve being created is supplied to the display device 8 via the graph information memory 13 at each time, as shown in FIG.
As shown in FIG. 12D, a time-density curve is displayed along with the cumulative addition image while gradually growing in real time as the contrast agent flows in.

When the operator determines that the time density curve is in the state shown in FIG. 13 (a) and the contrast agent has sufficiently flowed out of the ROI from this state, he or she presses a freeze button, for example, on an input device (not shown). When instructed, measurement of various times is started. At this time, the switch 76 of the max hold unit 75 is set to the OFF state, and the sum total value D of the new frame is not input to the max hold unit 75. Therefore, the memory 79 stores the maximum value Dmax of the total sum D of all the frames before the start of time measurement, and the memory 82 stores the frame number FNmax of the maximum value Dmax.

Then, the maximum value Dmax is multiplied by the coefficient K (1/2) from the controller 14 in the threshold value generation unit 83 to generate the threshold value Dth. This threshold value Dth is supplied to the adder 87 of the time measuring unit 84. All the summation values D up to the current latest frame stored in the second ROI pixel summation value memory 85 of the time measuring unit 84 are supplied to the adder 87 via the −1 multiplier 86 in order from the past. , And the threshold value Dth. Whether the addition result is positive or negative is determined by the AND gate 89, and when it is negative, that is, when the total value D is larger than the threshold value Dth, the count value of the counter 90 is incremented each time. Here, the frame number FNmax stored in the memory 82 is supplied from the controller 14 to the counter 90, and counting is separately performed before and after the frame number FNmax. As a result, the number of frames having a total value D equal to or larger than the threshold value Dth until reaching the frame having the maximum value Dmax (hereinafter referred to as "inflow frame number") and the maximum value Dma
The number of frames having a total value D equal to or greater than the threshold value Dth after the frame of x (hereinafter referred to as "outflow frame number") is counted.

The number of frames is calculated by the multiplier 91.
Then, it is multiplied by the frame cycle time Ft at the time of transmitting / receiving ultrasonic waves supplied from the controller 14 and converted into a real time. Therefore, as shown in FIG. 14, the inflow time twi, the outflow time tw0, and the half width time th that is the total time of the inflow time tw and the outflow time tw0 are measured. These inflow time tw
i, the outflow time tw0, and the half width time th are shown in FIG. 13B via the measurement time memory 92 and the graphic generator 93.
As shown in FIG.

As described above, according to the present embodiment, a temporal change curve of the inflow / outflow amount of the contrast agent into the region of interest (ROI), that is, a time density curve can be created in real time, and the region of interest of the contrast agent can be created. Inflow to (ROI),
Time information of outflow time and half-width time can be measured.

Further, in the present embodiment, two log compressors having different dynamic ranges are used and are selectively used in the normal mode and the contrast agent mode, so that good contrast is obtained in the normal mode. In contrast agent mode, the signal of the contrast agent can be log-compressed without being saturated.

Although the two log compressors having different dynamic ranges are used in the above-mentioned embodiment, one log compressor may be used to switch the dynamic range between the normal mode and the contrast medium mode. Good. In this case, as shown in FIG. 15, the output of the log compressor 17 capable of operating in at least two types of dynamic ranges is connected to the first frame memory 6 and the second frame memory 6 via the switch 18.
Of the log compressor 17 under the control of the controller 14 to switch the switching of the dynamic range of the log compressor 17 and the switching of the switch 18 between the normal mode and the contrast agent mode. This can be realized by providing the generator 19.

FIG. 16 shows the configuration of the third embodiment of the present invention. In this embodiment, when the contrast agent mode is set, the received signal does not pass through the second log compressor 5 by the switch 5A, the second frame memory 9, the contrast agent signal detection unit 10, the contrast agent signal memory. 11, graph calculation unit 12
And the case of being supplied to the graph information memory 13 and passing through the second log compressor 5, the second frame memory 9, the contrast agent signal detection unit 10, the contrast agent signal memory 11, and the graph calculation unit 12
And the case of being supplied to the graph information memory 13 are realized. This configuration appropriately sets a time-varying curve of image data in a region of interest in an ultrasonic image whose dynamic range is not adjusted and a time-varying curve of image data in a region of interest in an ultrasonic image whose dynamic range is adjusted. Obtainable.

A fourth embodiment of the present invention will be described with reference to FIGS. In the fourth embodiment, a plurality of regions of interest ROI are set in one ultrasonic image, a time density curve is created for each ROI from the scattering intensity within each ROI, and, for example, the characteristics of the diagnosis target existing between ROIs. The amount (clinical data) is extracted by calculation and the clinical data is displayed. In this example, it is necessary to investigate the correlation of the time density curves for each ROI. Then, it is necessary to quantify how the diagnostic target such as a tumor responds to blood flow. As shown in FIG. 17, an ultrasonic image 400 is displayed on the screen 8A. In the image 400, the inflow path 401 and the outflow path 40 of the blood vessel are shown.
2 and the diagnosis target 403 exist. An area corresponding to the inflow path 401 is defined as ROI1, and an area corresponding to the outflow path 402 is defined as ROI2. As shown in the right graph, the scattering intensity curves of each ROI1 and ROI2 can be easily obtained by the above-mentioned embodiment.

Here, the system model shown in FIG. 18 is assumed. Here, the Fourier transform of the step function s (t) is S (ω), and the inverse Fourier transform of S (ω) is s
(T). The Fourier transform of the input function i (t) is I
(Ω), and the inverse Fourier transform of I (ω) is i (t). The Fourier transform of the output function o (t) is O (ω), and the inverse Fourier transform of O (ω) is o (t). The Fourier transform of the response function h (t) is H (ω), and H
The inverse Fourier transform of (ω) is h (t).

H (ω) obtained by Fourier transforming the response function h (t) to be obtained is as follows. H (ω) = S (ω) · (O (ω) / I (ω)) As an example of the feature quantity, the time tp at which h (t) becomes maximum and the half-value width time t1 / 2 of h (t) Is.

A concrete operation block of the above system model is shown in FIG. The system shown in FIG. 19 includes a Fourier transform unit 301 and an S (ω) memory 302.
And registers 303 to 305, 307 to 309, and h
(T) Controller 1 that also serves as arithmetic unit 306, switches 310 to 312, adder 313, and controller 14 described above.
4 '. This system may have either a hardware configuration or a software configuration.

Further, referring to the above equation, the h (t) computing unit 306 performs zero divide processing on I (ω) and obtains H (ω), and the inverse Fourier transform of this H (ω) is performed. By doing so, h (t) is obtained.

I (t) and o (t) are input to the Fourier transform unit after the time density curves have been created. FIG. 20 is a display example of h (t). Next, the fourth
A fifth embodiment will be described.

The present embodiment is intended to solve the problem that beat noise occurs in each image due to the influence of mutual ultrasonic waves by simultaneously observing two distant portions, for example, two portions of the carotid artery and the internal pulse. is there.

The fourth and fifth embodiments are shown in FIG. 21 or FIG.
Any of the two configurations may be used. In either configuration,
It has at least two probes 101 and 102 having the same configuration. Each probe 101, 102 has a plurality of transducers arranged one-dimensionally.

In the case of FIG. 21, each probe 101, 102
Corresponding to, the transmission / reception circuits 103 and 104, B mode processing systems 105 and 106, color flow mapping (CFM)
Two processing systems 107 and 108 and two display systems 109 and 110 are provided, and a monitor 1 is provided for both display systems 109 and 110.
11 is connected. In addition, transmission / reception driving of the probes 101 and 102 by the transmission / reception circuits 103 and 104,
The control circuit 112 is controlled so that beat noise is not generated in each image due to the influence of mutual ultrasonic waves, or simultaneously in a time-sharing manner for each frame or each raster (scanning line).
To provide. The B-mode processing systems 105 and 106 have the same configuration as in FIG. 3 and can generate a B-mode image, create a time density curve, and measure various times.

The B-mode processing systems 105 and 106 have the same structure as shown in FIG. 3, that is, two systems of log compressors having different dynamic ranges are connected to the output of the transmitting / receiving circuit, and the transmitting / receiving circuit 103, Each of the outputs of 104 is subjected to log compression, and the result is used as the luminance information for ROI.
Output to the display systems 109 and 110 via the marker adder.

The first log compressor output has the first
Frame memory is connected. Further, the output of the second log compressor is sent to the contrast agent signal detection unit that extracts the contrast agent component via the second frame memory. This contrast agent signal is displayed on the display system 109, 1 via the two-dimensional contrast agent signal memory.
Supplied to 10. This contrast agent signal is also supplied to the graph calculator. The graph calculation unit uses the contrast agent signal to create a time density curve and measures various time information such as inflow time and outflow time. The output of the graph computing unit is output via the two-dimensional graph information memory to the display system 109,
110.

Further, the color flow mapping processing system 10
Although not shown, the reference numerals 7 and 108 include a phase detection circuit, an A / D converter, an MTI (Moving-Target-Indicator) filter, an autocorrelator, and a calculation unit. The phase detection circuit receives a reception signal from the reception system 5, performs quadrature detection on the reception signal, removes a high frequency component by a low-pass filter (not shown), and removes the Doppler shift signal, that is, the Doppler shift signal for the blood flow image. Obtain the detection output. In addition to blood flow information, this Doppler detection output also includes unnecessary reflection signals (clutter components) from slow-moving objects such as the heart wall.
Therefore, the Doppler detection output is converted into a digital signal by an A / D converter and passed through an MTI filter.

Here, MTI is a technique used in radar, and as described above, Moving-Target-Indicator
Is a method of detecting only a moving target using the Doppler effect. Therefore, the MTI filter detects the motion of the blood flow by the phase change between the same pixels in the rate pulse repeatedly transmitted a predetermined number of times, and removes the clutter component. The autocorrelator frequency-analyzes the signal from which the clutter component has been removed in real time for each of the two-dimensional multipoints. The number of operations for frequency analysis by the autocorrelator is much smaller than the number of operations for the FFT (Fast Fourier Transform) method, and therefore real-time processing is possible. The arithmetic unit receives the output of the autocorrelator and has an average velocity arithmetic unit, a variance arithmetic unit, and a power arithmetic unit. In this calculation unit, the average speed calculation unit obtains the average Doppler shift frequency fd, the variance calculation unit obtains the variance σ ² , and the power calculation unit obtains the power P.

Further, in the case of FIG. 22, by connecting one transmission / reception circuit 114 to at least two probes 101 and 102 via a switch (MUX) 113, the probes 101 and 102 can be selectively transmitted to the transmission / reception circuit 114. To be able to connect to. A B-mode processing system 115 and a color flow mapping (CFM) processing system 116 are connected in parallel to the output of the transmission / reception circuit 114. These B-mode processing system 1
15 and the output of the color flow mapping processing system 116 are
It is displayed on the monitor 118 via one display system 117. By the switching operation of the switch 113, the probes 101 and 102 are alternately driven by the transmission / reception circuit 114 for each frame or each raster in a time division manner. At the same time, when actually using such a device, as shown in FIG. 23, one probe 101 is installed in, for example, the carotid artery, and the other probe 102 is installed in, for example, the portal vein, which is separated from the probe 101.

After injecting the contrast agent into the subject P from the contrast agent injecting device 120, the two probes 101 and 102 are synchronized with each other or time-divisionally transmitted / received for each frame or each raster, so that the other one of the two probes 101, 102 is driven. Both images can be displayed at the same time as shown in FIG. 24 without being affected by the ultrasonic waves emitted from the probe and thus without causing beat noise in each image.

Further, in the case of the configuration shown in FIG. 22, the two probes 101 and 102 are driven by the same transmission / reception circuit 114, and the B mode image and the color flow mapping image are obtained by the same processing system. Differences in standard signal levels due to differences in gain characteristics, etc. are eliminated, so that comparison between both images can be performed under the same conditions.

[0061]

As described above, according to the present invention, it is possible to provide an ultrasonic diagnostic apparatus capable of preventing the contrast agent component of the received signal from protruding from the dynamic range and being saturated. Also,
ADVANTAGE OF THE INVENTION According to this invention, the ultrasonic diagnosing device which can provide various information, such as a time-dependent change of the inflow / outflow amount of a contrast medium to a region of interest, in real time can be provided.

Further, according to the present invention, it is possible to provide an ultrasonic diagnostic apparatus capable of collecting images of two distant portions in real time while suppressing the occurrence of beat noise due to the influence of the ultrasonic waves of the other one.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a first embodiment of an ultrasonic diagnostic apparatus according to the present invention.

FIG. 2 is a block diagram showing the configuration of a second embodiment of the ultrasonic diagnostic apparatus according to the present invention.

FIG. 3 is a block diagram showing the configuration of a third embodiment of the ultrasonic diagnostic apparatus according to the present invention.

FIG. 4 is a diagram showing an example of a contrast agent mode input unit in FIG.

5 is a diagram showing the dynamic range of the log compressor of FIG.

6 is a block diagram showing the configuration of the ROI marker adder of FIG.

7 is a block diagram showing the configuration of a contrast agent signal detection unit in FIG.

8 is a block diagram showing a configuration of a graph calculation unit in FIG.

FIG. 9 is a diagram showing screens before and after adding an ROI marker to an image.

10 is a diagram for explaining an average value calculation process by the average value calculation unit in FIG. 7.

FIG. 11 is a diagram showing two types of signals output from the contrast agent signal detection unit of FIG. 3, the amount of change in the contrast agent signal between frames and the cumulative value thereof.

FIG. 12 is a diagram showing changes in the display screen until the start of time measurement.

FIG. 13 is a diagram showing a display position of a completed time density curve and measurement time.

FIG. 14 is a diagram showing various times measured by the time measuring section of FIG.

FIG. 15 is a block diagram showing a configuration of a modified example of the third embodiment.

FIG. 16 is a block diagram showing the configuration of another modification of the third embodiment.

FIG. 17 is a diagram showing the principle of the fourth embodiment.

FIG. 18 is a diagram showing a system model of a fourth embodiment.

FIG. 19 is a block diagram showing the configuration of a fourth embodiment.

FIG. 20 is a diagram showing a display example in the fourth embodiment.

FIG. 21 is a block diagram showing the configuration of the fifth embodiment.

FIG. 22 is a block diagram showing another configuration of the fifth embodiment.

FIG. 23 is a diagram showing how two probes are installed on a subject.

FIG. 24 is a diagram showing a display screen.

[Explanation of symbols]

1 ... Ultrasonic probe, 2 ... Transmission system, 3 ... Reception system, 4 ...
1st log compressor, 5 ... 2nd log compressor, 6 ... 1st frame memory, 7 ... ROI mer addition device, 8 ... Indicator, 9 ... 2nd frame memory, 10 ... Contrast agent signal detection part, 11 ... Contrast agent signal memory, 12 ... Graph computing section, 13 ... Graph information memory, 14 ... Controller, 15 ... Bus line, 16 ... Contrast agent mode input section, 200 ... Transmitting section, 201 ... Receiving section,
Reference numeral 202 ... Signal processing unit, 203, 207 ... Conversion unit, 204
... Display unit 205 ... Control unit 206 ... Setting unit.

Claims (12)

[Claims] 1. A transmission / reception unit for transmitting / receiving ultrasonic waves to / from an object to obtain an ultrasonic reception signal, and an ultrasonic image having a predetermined dynamic range by signal-processing the ultrasonic reception signal obtained by the transmission / reception unit. A signal processing section for obtaining the ultrasonic wave image, a conversion section for converting an ultrasonic image having a predetermined dynamic range obtained by the signal processing section into an ultrasonic image having a dynamic range different from the predetermined dynamic range, and the conversion section An ultrasonic diagnostic apparatus comprising: a display unit that displays an ultrasonic image obtained by the above. 2. The conversion unit includes storage means for storing a plurality of different log compression curves, reading means for reading one log compression curve from the storage means, and one log read by the reading means. Based on the compression curve, an ultrasonic image having a predetermined dynamic range obtained by the signal processing unit is arithmetically processed to have a specific dynamic range defined by one log compression curve read by the reading means. The ultrasonic diagnostic apparatus according to claim 1, further comprising a calculation unit that obtains an ultrasonic image. 3. The conversion unit includes a plurality of log compressors having different log compression characteristics, and the plurality of log compression units that should log-compress an ultrasonic image having a predetermined dynamic range obtained by the signal processing unit. A selection means for selecting one of the containers.
The ultrasonic diagnostic apparatus according to item 1. 4. The ultrasonic diagnostic apparatus according to claim 2, wherein one of the plurality of log compression curves has a log compression characteristic corresponding to an ultrasonic reception signal from a subject injected with a contrast agent. . 5. A log compression curve corresponding to a received signal from a subject injected with a contrast agent when the contrast agent mode setting means is set. The ultrasonic diagnostic apparatus according to claim 2, wherein 6. A log compression curve having a log compression characteristic corresponding to an ultrasonic wave reception signal from a subject into which a contrast agent has been injected has a change in output signal with respect to a change in input signal value in a portion where the input signal is large. The ultrasonic diagnostic apparatus according to claim 4, wherein the rate is set to be larger than those of other log compression curves. 7. Setting means for setting a region of interest in an ultrasonic image obtained by the conversion unit or the signal processing unit, and an interest to be displayed on the display unit, the interest set by the setting unit. The ultrasonic diagnostic apparatus according to claim 1, further comprising: a calculating unit that obtains a temporal change curve of the image data in the region. 8. A plurality of ultrasonic probes for transmitting and receiving ultrasonic waves to and from different parts of a subject, and a plurality of ultrasonic probes for transmitting and receiving the plurality of ultrasonic probes, the ultrasonic probe being composed of a plurality of scanning lines. One transmission / reception unit for obtaining a sound wave image, a switching unit for time-divisionally switching the combination of connection between each ultrasonic probe of the plurality of ultrasonic probes and the transmission / reception unit, and a region of interest in the ultrasonic image for each frame A setting unit for setting, a calculation unit for almost simultaneously obtaining a temporal change curve of image data in the region of interest of the ultrasonic image for each frame set by the setting unit, and the plurality of calculation units An ultrasonic diagnostic apparatus comprising: a display unit that simultaneously displays a temporal change curve. 9. The switching unit is configured to scan each frame or to scan one frame.
9. The ultrasonic diagnostic apparatus according to claim 8, further comprising means for time-divisionally switching a combination of connection between each ultrasonic probe of the plurality of ultrasonic probes and the transmission / reception unit for each scanning after scanning. 10. A transmission / reception unit for transmitting / receiving ultrasonic waves to / from a subject to obtain an ultrasonic reception signal, and a signal processing unit for signal-processing the ultrasonic reception signal obtained by the transmission / reception unit to obtain an ultrasonic image. Setting means for setting a region of interest in a plurality of ultrasonic images obtained by the signal processing unit, means for obtaining the temporal change curve of the image data in the plurality of regions of interest set by the setting means almost at the same time, An ultrasonic diagnostic apparatus comprising: an ultrasonic image obtained by the signal processing unit and a display unit that simultaneously displays the plurality of temporal change curves obtained by the means. 11. The ultrasonic diagnostic apparatus according to claim 10, further comprising means for calculating information indicating a relationship between the plurality of temporal change curves and providing the information to the display means. 12. A transmission / reception unit for transmitting / receiving ultrasonic waves to / from an object to obtain an ultrasonic reception signal, and signal processing for signal-processing the ultrasonic reception signal obtained by the transmission / reception unit to obtain an ultrasonic image in frame units. Section, a setting section for setting a region of interest in an ultrasonic image in frame units obtained by the signal processing section, a filtering section for performing filtering between the regions of interest for each frame set by the setting section, and A calculation unit for obtaining a temporal change curve of the image data in the region of interest based on the image data of the region of interest filtered by the unit; and a display for displaying the temporal change curve obtained by the calculation unit. And an ultrasonic diagnostic apparatus.