JP2001286471A - Ultrasonic diagnostic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control the timing of receiving of ultrasonic waves by calculating the peak value of the bloodstream from the Doppler signal of the bloodstream of a subject and using the time phase of the bloodstream peak in an ultrasonic diagnostic apparatus. SOLUTION: In the ultrasonic diagnostic apparatus, ultrasonic waves are transmitted/received with a probe 1 inside a subject, and the received reflection echo signal is processed to form an image signal, which is displayed as an ultrasonic image. The ultrasonic diagnostic apparatus has means (9, 10, 11) for operating the Doppler signal of the bloodstream based on the reflection echo signal, calculating the peak value of the bloodstream based on the Doppler signal, and controlling the timing of transmission/receiving of ultrasonic waves by using the time phase of the bloodstream peak. Because of these means, the timing of transmission/receiving of ultrasonic waves can be controlled by using the time phase of the bloodstream peak obtained from the reflection echo signal.

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 which transmits and receives an ultrasonic wave into a subject and creates and displays an ultrasonic image of a diagnostic site using a reflected echo signal. The present invention relates to an ultrasonic diagnostic apparatus that improves the image quality of an image by harmonic imaging using a time phase having a maximum value of a blood flow velocity obtained from a signal.

[0002]

2. Description of the Related Art A conventional ultrasonic diagnostic apparatus of this kind is shown in FIG.
As shown in FIG. 1, a probe 1 for transmitting and receiving an ultrasonic wave into a subject
And an ultrasonic transmission / reception unit 2 that drives the probe 1 to transmit ultrasonic waves and amplifies the received reflected echo signal.
And a digital scan converter (hereinafter abbreviated as "DSC") 3 for writing and reading the image signal from the ultrasonic transmission / reception unit 2, converting the image signal into a display coordinate system, and outputting the converted signal.
An input unit 4 for inputting by an operator; a graphic display unit 5 for processing image display; a synthesizing circuit 6 for synthesizing image information from the DSC 3 and information from the graphic display unit 5; An image display device 7 for displaying an image signal from the circuit 6, an ECG unit 8 for obtaining an electrocardiographic waveform of the subject, and a control unit 9 for controlling the operation of each of the above components are provided. Was.

The probe 1 transmits and receives ultrasonic waves to and from the subject, and the reflected echo signals received by the probe 1 are signal-processed by the ultrasonic transmitting and receiving unit 2 and the DSC 3,
The processed image information is displayed on the image display device 7 as an ultrasonic image. At this time, the electrocardiographic waveform of the subject is expressed as E
The timing at which the CG unit 8 detects and uses this as a trigger to transmit and receive the ultrasonic wave is controlled by the control unit 9 to form an ultrasonic tomographic image in an arbitrary cardiac phase.

[0004] In recent years, a method called harmonic imaging has been used in which microbubbles are sent into a blood vessel, and the bubbles are ruptured by transmission of ultrasonic waves to obtain a contrast function to clearly depict the inside of the heart.

[0005]

However, in such a conventional ultrasonic diagnostic apparatus, the electrocardiographic waveform of the subject is used as a trigger for controlling the timing of transmission and reception of the ultrasound. To detect the radio wave shape, E
The electrodes of the CG section 8 must be mounted on the subject, which requires time and effort to mount the electrodes, which places a burden on the subject and the operator.

In addition, the ultrasonic transmission / reception repetition frequency (PR
Since F) was controlled in accordance with the electrocardiographic waveform, if the subject's electrocardiographic waveform was unstable, the PRF did not match the subject's electrocardiographic time phase, and was adjusted to the electrocardiographic time phase. Could not form an ultrasonic image. For this reason, the above-described harmonic imaging method may not be properly applied during ultrasonic diagnosis.

Accordingly, the present invention addresses such a problem and provides an ultrasonic diagnostic which improves the image quality of an image by harmonic imaging using a time phase having a maximum value of a blood flow velocity obtained from a reflected echo signal. It is intended to provide a device.

[0008]

In order to achieve the above object, an ultrasonic diagnostic apparatus according to the present invention transmits and receives ultrasonic waves to and from a subject using a probe and processes the received reflected echo signals. In an ultrasonic diagnostic apparatus that forms an image signal and displays the image signal as an ultrasonic image, a Doppler signal of a blood flow is calculated based on the reflected echo signal, and a maximum value of a blood flow velocity is calculated from the Doppler signal. A means for calculating and setting the ultrasonic transmission / reception repetition frequency using the time phase at which the maximum value is obtained is provided.

[0009]

Embodiments of the present invention will be described below in detail 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 creates and displays an ultrasonic image of a diagnostic site using a reflected echo signal transmitted and received within a subject, as shown in FIG.
, An ultrasonic transmitting and receiving unit 2, a digital scan converter (hereinafter abbreviated as “DSC”) 3, an input unit 4, a graphic display unit 5, a synthesizing circuit 6, and an image display device 7.
And a control unit 9, and further includes a Doppler operation unit 10 and a blood flow peak calculation unit 11.

The probe 1 transmits an ultrasonic wave toward a diagnostic site in a subject and receives a reflected echo. Although not shown, the probe 1 serves as a source of ultrasonic waves and a reflected echo signal. And is formed, for example, in a sector scanning probe.

The ultrasonic transmitting / receiving section 2 drives the probe 1 to transmit ultrasonic waves and amplifies a received reflected echo signal. Although not shown, the ultrasonic transmitting / receiving section 2 includes therein the probe 1 A transmitting circuit that supplies a transmitting pulse to the probe to generate ultrasonic waves from a built-in vibrator, a receiving amplifier that amplifies a reflected echo signal received by the probe 1, and a control circuit that controls them. are doing.

The DSC 3 writes an image signal from the ultrasonic transmission / reception unit 2, reads the signal, converts the signal into a display coordinate system, and outputs it. The DSC 3 writes the ultrasonic information digitized by the A / D converter inside the ultrasonic transmission / reception unit 2 into a built-in line memory for each scanning line or a plurality of scanning lines of the ultrasonic beam, and obtains a tomographic image. (B-mode image) image data is generated.

The input unit 4 is used to input a command such as the number of beats of the subject's heartbeat to be transmitted / received to / from an ultrasound image or a character displayed on an image display device 7 described later. , For example, a trackball or a mouse. The graphic display unit 5 processes information of the command set by the input unit 4 for display.

The synthesizing circuit 6 synthesizes the image information converted and output by the DSC 3 and the information processed by the graphic display unit 5, and outputs an image signal. The image display device 7 receives the image signal synthesized by the synthesis circuit 6 and displays the image as an image.
RT, etc.

The control unit 9 includes the ultrasonic transmission / reception unit 2 described above,
It controls the DSC 3, the input unit 4, the graphic display unit 5, the synthesizing circuit 6, and the image display device 7.

Here, the ultrasonic diagnostic apparatus according to the present invention is provided with a Doppler calculation unit 10 and a blood flow peak calculation unit 11. The Doppler calculation unit 10 calculates the Doppler signal of the blood flow of the subject based on the reflected echo signal received by the ultrasonic transmission / reception unit 2, and is controlled by a control signal from the control unit 9. ing. The blood flow peak calculation unit 11 is controlled by a control signal from the control unit 9 and calculates the maximum value of the blood flow velocity from the Doppler signal of the blood flow calculated by the Doppler calculation unit 10. Phase
This is transmitted to the control unit 9 as a trigger for controlling the timing of transmission and reception of ultrasonic waves. The control unit 9 transmits a control signal to the ultrasonic transmission / reception unit 2 using the time phase of the maximum value of the blood flow velocity from the blood flow peak calculation unit 11 as a trigger, and the probe 1 transmits the ultrasonic wave. Timing of transmission / reception, ie, PR
F is controlled.

Next, the operation of the ultrasonic diagnostic apparatus thus configured will be described. First, in FIG. 1, when a transmission pulse is supplied from the ultrasonic transmission / reception unit 2, the probe 1 transmits an ultrasonic wave into the subject, and the transmitted ultrasonic wave is reflected at the diagnostic site and returned. The probe 1 receives the reflected echo. The reflected echo is amplified by the ultrasonic transmission / reception unit 2 and digitized by the A / D converter therein, and the digitized ultrasonic information is transmitted to the DSC 3 for each scanning line or a plurality of scanning lines of the ultrasonic beam. The information is written into a built-in line memory, and image information of a tomographic image (B-mode image) is generated from the ultrasonic information. Also, the input unit 4
Is processed for display on the graphic display unit 5. Then, the image information generated by the DSC 3 and the information processed by the graphic display unit 5 are synthesized by a synthesizing circuit 6, and the synthesized image signal is displayed by an image display device 7.

At this time, in the present invention, the Doppler operation unit 10 calculates the Doppler signal of the blood flow of the subject based on the received reflected echo signal. The calculated Doppler signal is input to the blood flow peak calculator 11 and is held as data of the blood flow Doppler waveform D shown in FIG. Then, the blood flow peak calculator 11 calculates a blood flow peak P from the stored data. Next, the blood flow peak calculation unit 11
The time phase of the maximum value P of the blood flow velocity is sent to the control unit 9. Then, the control unit 9 transmits a control signal for transmitting and receiving the ultrasonic wave to the ultrasonic transmitting and receiving unit 2 with the time phase of the maximum value P of the blood flow velocity as a trigger, and the ultrasonic transmitting and receiving unit 2 receiving the signal transmits the control signal. The probe 1 is driven to transmit and receive ultrasonic waves. By operating the means for controlling the timing of the transmission and reception of the ultrasonic waves in this manner, the ultrasonic diagnostic apparatus according to the present invention can synchronize the transmitted and received ultrasonic waves with the cardiac phase of the subject. By controlling the timing of transmitting and receiving the ultrasonic waves in synchronization with the cardiac phase, it is possible to form a favorable ultrasonic image by the harmonic imaging method.

FIG. 3 shows a second example of the ultrasonic diagnostic apparatus shown in FIG.
It is a block diagram which shows the example of. In the example of FIG. 3, a counter 12 is provided between the blood flow peak calculator 11 and the controller 9. This counter 12 counts the heart rate of the subject. With the provision of the counter 12, it is possible to execute a command input to the input unit 4, for example, an operation command such as how many ultrasonic waves are transmitted and received with respect to the heart rate of the subject. In other words, the control unit 9 can control the trigger to be transmitted to the ultrasonic transmission / reception unit 2 using the heart rate of the subject counted by the counter 12, thereby synchronizing the heart time phase with each heartbeat. It becomes possible to transmit and receive ultrasonic waves. Therefore, Transient Repetition Imaging (hereinafter, “TRI”) that transmits and receives ultrasonic waves at a timing of once every one to several heart beats in synchronization with the cardiac phase of the subject
Myocardial staining by the method).

FIG. 4 shows a third example of the ultrasonic diagnostic apparatus shown in FIG.
It is a block diagram which shows the example of. In the example of FIG. 4, a delay circuit 13 is provided between the blood flow peak calculation unit 11 and the control unit 9. The delay circuit 13 delays the timing at which the maximum value of the Doppler signal of the blood flow calculated by the blood flow peak calculator 11 is transferred to the controller 9. This delay circuit 1
3, the ultrasonic transmission / reception unit 2 which has received the control signal for transmission / reception of the ultrasonic wave via the control unit 9 can transmit / receive the ultrasonic wave with an arbitrary time phase from the blood flow peak. Becomes Therefore, Flash Echo Imaging (hereinafter referred to as “F”) that transmits and receives ultrasonic waves at a timing delayed from the cardiac phase of the subject by a certain time, for example, 1/6 to 10 seconds.
Myocardial staining by the "EI" method).

FIG. 5 shows a fourth embodiment of the ultrasonic diagnostic apparatus shown in FIG.
It is a block diagram which shows the example of. In the example of FIG. 5, a counter 12 and a delay circuit 13 are provided between the blood flow peak calculation unit 11 and the control unit 9. By providing the counter 12 and the delay circuit 13, it is possible to transmit and receive ultrasonic waves delayed by an arbitrary time phase from the blood flow peak for each arbitrary heart rate. Therefore, myocardial staining using both the above-described TRI method and FEI method becomes possible.

[0022]

The present invention has been configured as described above.
The Doppler signal of the blood flow is calculated based on the reflected echo signal received by the probe, the peak value of the blood flow is calculated from the Doppler signal, and the ultrasonic wave transmission / reception timing is calculated using the time phase of the blood flow peak. Can be controlled. By controlling the timing of ultrasonic transmission and reception using the time phase of the blood flow peak as a trigger, an ultrasonic image in an arbitrary cardiac time phase can be configured. Further, since the time phase of the blood flow peak is used as a trigger, the timing of ultrasonic transmission / reception is appropriate even when the electrocardiographic waveform of the subject is unstable, and an accurate ultrasonic image in any cardiac phase is formed. It becomes possible. Further, since the electrocardiographic waveform does not need to be used as a trigger for controlling the timing of transmitting and receiving the ultrasonic waves, the labor and time for mounting the electrodes of the ECG unit on the subject can be saved.

[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 a graph showing a Doppler waveform held by a blood flow peak calculation unit.

FIG. 3 is a block diagram showing a second example of the ultrasonic diagnostic apparatus shown in FIG.

FIG. 4 is a block diagram showing a third example of the ultrasonic diagnostic apparatus shown in FIG.

FIG. 5 is a block diagram showing a fourth example of the ultrasonic diagnostic apparatus shown in FIG.

FIG. 6 is a block diagram showing a conventional ultrasonic diagnostic apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Probe 2 ... Ultrasonic transmission / reception part 3 ... DSC 4 ... Input part 5 ... Graphic display part 6 ... Synthesizing circuit 7 ... Image display device 9 ... Control part 10 ... Doppler calculation part 11 ... Blood flow peak calculation part 12 ... Counter 13: delay circuit D: Doppler waveform P: blood flow peak

Claims (1)

[Claims] 1. A probe transmits and receives an ultrasonic wave into and from a subject,
The received reflected echo signal is processed to form an image signal, and in an ultrasonic diagnostic apparatus that displays the image signal as an ultrasonic image, a Doppler signal of blood flow is calculated based on the reflected echo signal. An ultrasonic diagnostic apparatus comprising: means for calculating a maximum value of a blood flow velocity from a Doppler signal, and setting an ultrasonic transmission / reception repetition frequency using a time phase at which the maximum value is obtained.