JP2006014938A - Ultrasonic diagnostic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic diagnosing apparatus capable of being advantageously used in diagnoses using a plurality of ultrasonic contrast agents. <P>SOLUTION: Sound pressure conditions of transmitting ultrasonic waves according to the kinds of a plurality of contrast agents and a transmitting sequence in which the combination of arbitrary sound pressure conditions and its executing order are stored in a set memory portion 21, a plurality of kinds of ultrasonic contrast agents introduced into the body of a subject are selectively ruptured by controlling the sound pressure of the transmitting ultrasonic wave according to the transmitting sequence. Further, an image storing portion 15 storing the captured ultrasonic images independently according to the sound pressure conditions at the time of imaging and an image combining portion 16 calculating and combining the respective images are arranged to make it possible to combine and display the images photographed in different sound pressure conditions together. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an ultrasonic diagnostic apparatus that acquires information inside a subject by transmitting and receiving ultrasonic waves, and particularly relates to an ultrasonic diagnostic apparatus that can be suitably used for evaluation of blood flow dynamics using a contrast agent. .

  The ultrasonic diagnostic apparatus transmits an ultrasonic wave from a probe applied to the body surface of the subject, receives an ultrasonic signal reflected by each tissue in the body of the subject, and a time difference between the transmission signal and the received signal. Based on the above, it is a device for obtaining information in the body of a subject, and is widely used for various diagnoses because of its high safety.

  Ultrasound diagnostic equipment has been used for the purpose of observing tomographic images of internal tissues for a long time, but with the development of an ultrasonic Doppler method that utilizes changes in the reflected wave frequency due to the Doppler effect, it is now used to evaluate blood flow dynamics. Is also widely used. However, the ultrasonic Doppler method can detect a portion with a relatively large blood flow, but it is difficult to detect a micro blood flow such as a capillary blood vessel. Therefore, as described in Patent Document 1, a technique for enhancing blood flow information by injecting an ultrasound contrast agent into a blood vessel has been developed. Such a method is called a contrast echo method, and is effective for evaluating the blood perfusion state of the myocardium, identifying the blood flow into the tumor, and differential diagnosis of the tumor lesion. Ultrasound contrast agent used for contrast echo method contains minute bubbles as a reflection source, and the acoustic impedance of the bubbles is different from the acoustic impedance of internal tissues and blood components. A strong echo signal is obtained.

However, since the microbubbles of the contrast agent burst when subjected to a high sound pressure, it is necessary to perform ultrasonic observation at a relatively low sound pressure in order to maintain the contrast effect. Conversely, a technique called a flash echo imaging method that uses this property to rupture a contrast agent at a high sound pressure at a time and image a strong echo signal generated at that time is also widely used.
JP-A-8-280674 ([0003])

Currently, there is only one type of ultrasound contrast agent marketed in Japan, but the commercialization of a new ultrasound contrast agent is planned in the future, and the application field of contrast echo method is expected to expand further. .
For example, if two types of contrast agents with different burst sound pressures are introduced into the body and they can be individually ruptured, it is thought that more detailed blood flow evaluation will be possible. There are only two types of sound pressure settings: sound pressure that ruptures one existing contrast agent and sound pressure that does not rupture. Therefore, when a conventional ultrasonic diagnostic apparatus is used to selectively rupture each of a plurality of ultrasonic contrast agents introduced into the body, the operator transmits sound pressure using an input panel or the like each time. There is a problem that the operation is complicated.

  That is, the problem to be solved by the present invention is to provide an ultrasonic diagnostic apparatus capable of easily performing a diagnosis using a plurality of ultrasonic contrast agents.

  An ultrasonic diagnostic apparatus according to the present invention, which has been made to solve the above problems, transmits and receives ultrasonic waves to and from a predetermined portion of a subject into which a contrast agent has been introduced, thereby allowing blood flow inside the subject to flow. In the ultrasonic diagnostic apparatus for acquiring information, a) a sound pressure condition storage unit that stores a sound pressure condition of a transmission ultrasonic wave corresponding to a plurality of types of contrast agents, and b) stored in the sound pressure condition storage unit A sequence storage means for storing a combination of sound pressure conditions selected from a plurality of sound pressure conditions and a transmission sequence that defines the execution order; and c) a transmission ultrasonic wave according to the transmission sequence stored by the sequence storage means. And a sound pressure control means for controlling the sound pressure.

  Still further, in the ultrasonic diagnostic apparatus of the present invention, d) image storage means for storing ultrasonic images photographed according to the transmission sequence according to sound pressure conditions at the time of photographing, and e) stored by the image storage means. It is desirable to provide image composition means for computing and composing each ultrasonic image.

  A transmission sequence in which a plurality of sound pressure settings corresponding to the burst sound pressures of various ultrasonic contrast agents and combinations and execution orders of sound pressure settings used for diagnosis are determined by the ultrasonic diagnostic apparatus of the present invention having the above-described configuration. Since ultrasonic diagnosis is performed according to the transmission sequence, ultrasonic diagnosis using a plurality of ultrasonic contrast agents can be easily performed.

  Further, by providing an image storage unit and an image composition unit, it is possible to store ultrasonic images according to sound pressure conditions at the time of photographing, and to synthesize and display ultrasonic images photographed under different sound pressure conditions. Therefore, the diagnostic property of ultrasonic diagnosis using a plurality of ultrasonic contrast agents can be improved.

  Hereinafter, the best mode for carrying out the present invention using an ultrasonic diagnostic apparatus according to an embodiment of the present invention will be described.

[Example]
FIG. 1 is a block diagram showing the configuration of the main part of the ultrasonic diagnostic apparatus of this embodiment. The ultrasonic probe 11 is for abutting on the body of a subject to transmit and receive ultrasonic waves. The ultrasonic probe 11 transmits ultrasonic waves to the subject based on the pulser voltage applied by the pulser circuit 12, and The ultrasonic wave reflected in the living body is received and converted into an electric signal. The echo signal output from the probe 11 is amplified by the amplifier 13 and is subjected to predetermined processing by the signal processing unit 14 to generate a tomographic image, a color flow mapping image, a flow velocity spectrum, and the like and display them on the monitor 18. The image storage unit 15 stores the image generated by the signal processing unit 14. The image composition unit 16 performs predetermined arithmetic processing on a plurality of pieces of image information stored in the image storage unit 15. By doing so, the image is synthesized. The display processing unit 17 performs processing for displaying an ultrasonic image, a flow velocity spectrum, and the like on the monitor 18 based on the image data output from the signal processing unit 14, the image storage unit 15, and the image synthesis unit 16.

  Each of the above units is controlled by a control unit 19, and an instruction from an operator is input to the control unit 19 through an input unit 20 including a pointing device such as a mouse, an input panel, and the like. The setting storage unit 21 stores settings such as a sound pressure condition and a transmission sequence described later. The pulsar voltage control unit 22 controls the pulsar voltage output from the pulsar circuit 12, and thereby adjusts the sound pressure of the transmission ultrasonic wave.

The ultrasonic diagnostic apparatus of the present embodiment can store sound pressure conditions of transmission ultrasonic waves according to the burst sound pressures of a plurality of ultrasonic contrast agents, and can be used in combination with any sound pressure condition or each sound pressure condition. It is possible to store a transmission sequence that defines the execution order of ultrasonic transmission according to. The sound pressure conditions and transmission sequence are stored in the apparatus as defaults, and a new sound pressure condition and transmission sequence can be created and registered by the operator performing a predetermined operation at the input unit 20. It may be.
As the transmission sequence, in addition to the combination of sound pressure conditions to be executed and the order of execution, the time for executing ultrasonic transmission under each sound pressure condition is stored, and transmission under one sound pressure condition is performed. It is desirable to automatically shift to the next sound pressure condition after the time has passed, but without performing such time setting, the operator can input during transmission under a certain sound pressure condition. By performing a predetermined operation in the unit 20, the transmission may be shifted to the next sound pressure condition.

Subsequently, an operation at the time of ultrasonic diagnosis using the ultrasonic diagnostic apparatus of the present embodiment will be described. Here, an example will be described in which diagnosis is performed using two types of ultrasonic contrast agents having different burst sound pressures (contrast agent A being the lower burst sound pressure and contrast agent B being the higher burst sound pressure).
First, the operator sets a transmission sequence used for diagnosis by performing a predetermined operation with the input unit 20 before starting diagnosis. Here, an example is shown in which a transmission sequence as shown in FIG. 2 is selected from a plurality of transmission sequences stored in the apparatus in advance and executed. In this transmission sequence, at time T0 to T1, the sound pressure that does not rupture both contrast agents A and B, at time T1 to T2, the contrast agent A ruptures but does not rupture contrast agent B, and at time T2 to T3, the contrast agent Both A and B are set to transmit ultrasonic waves with sound pressure that bursts.

  When the setting of the transmission sequence is completed, the contrast agents A and B are introduced into the body of the subject by a predetermined method. These contrast agents may be introduced at the same time, or may be introduced sequentially with time.

Subsequently, the operator brings the probe 11 into contact with the diagnosis target region of the subject's body, and starts ultrasonic transmission according to the transmission sequence by performing a predetermined operation with the input unit 20.
From time T0 to T1, since neither the contrast medium A nor the contrast medium B in the body is ruptured, an image similar to a conventional contrast echo is obtained. Subsequently, by switching to the next sound pressure condition at time T1, the contrast agent A bursts and a strong echo signal is obtained. On the other hand, since the contrast medium B does not rupture, the contrast medium B gradually flows to a site where the blood flow is low. Thereafter, at time T2, contrast agent B is also destroyed and emits a strong echo signal (contrast agent A has already disappeared from the examination region at time T1, so only the echo signal derived from contrast agent B is obtained). When transmission according to a series of transmission sequences is completed at time T3, ultrasonic transmission is started again at a sound pressure that does not rupture both contrast agents A and B, and within the diagnostic region where contrast agents A and B have disappeared. The contrast agents A and B again flow. Thereafter, ultrasonic transmission according to the transmission sequence is repeatedly performed until a predetermined end instruction operation is performed at the input unit 20.
Through the above series of operations, the normal contrast echo signal in a state where both of the contrast agents A and B are not ruptured, the strong echo signal in the region with a relatively high blood flow resulting from the rupture of the contrast agent A, and the contrast A strong echo signal of the micro blood flow region resulting from the rupture of agent B is obtained. In addition, it can be observed that the contrast medium B flows into the micro blood flow region from time T1 to T2.

  While performing the ultrasonic diagnosis according to the above transmission sequence, the ultrasonic image generated by the signal processing unit 14 based on the obtained echo signal is displayed on the monitor 18 in real time, and the image storage unit 15 Is remembered. In the image storage unit 15, each ultrasonic image is stored in association with the sound pressure condition for each sound pressure condition at the time of shooting. Therefore, after the diagnosis is completed, an ultrasonic image obtained under a specific sound pressure condition is called up. It can be displayed on the monitor 18.

Furthermore, each ultrasonic image stored in the image storage unit 15 for each sound pressure condition at the time of photographing can be arithmetically combined by the image combining unit 16. Here, composition refers to generating one image from two or more image data, and not only adding another image data to one image data, but also subtracting another image data from one image data. It is also included when doing. Note that the ultrasonic diagnostic apparatus of this embodiment is provided with a biological signal measuring unit 23 for measuring a biological signal such as an electrocardiogram signal as shown in FIG. 3, and synchronizes each ultrasonic image with the biological signal. It is desirable to do so. As a result, in the diagnosis of a part that periodically moves, such as the heart, each ultrasonic image can be synthesized in accordance with the period. Note that the biological signal is not limited to an electrocardiographic signal, and various signals derived from a periodic movement of the living body such as a heart sound signal and a pulse wave signal can be used.
The synthesized image is displayed on the monitor 18 after undergoing predetermined processing in the display processing unit 17. A plurality of types of images may be displayed on the monitor 18 at the same time, or only synthesized images may be displayed.

  Further, in the ultrasonic diagnostic apparatus of this embodiment, as shown in FIG. 4, a reception frequency selection unit 24 is provided, and only the frequency component of the reflected wave derived from each contrast agent is extracted from the echo signal. It would be desirable to be able to generate a sonic image. As a result, echo signals generated from the respective ultrasonic contrast agents can be individually observed. For example, when the reflected waves from the contrast medium A and the contrast medium B have a frequency distribution as shown in FIG. 5, if the reception frequency is fO at the time T1 to T2 of the transmission sequence, the echo from the contrast medium A If the reception frequency of the signal is f1, an echo signal from the contrast agent B can be selectively obtained.

  In addition, the said Example is an example to the last, A various change is accept | permitted within the scope of the present invention. For example, as a method of adjusting the transmission sound pressure, in addition to the method of adjusting the pulser voltage as described above, a method of adjusting the focus of the ultrasonic beam may be used.

The block diagram which shows the structure of the principal part of the ultrasonic diagnosing device which concerns on the Example of this invention. The figure which shows an example of the transmission sequence in the ultrasonic diagnosing device of the Example. The block diagram which shows the structure of the principal part of the ultrasound diagnosing device which has a biological signal measurement part. The block diagram which shows the structure of the principal part of the ultrasonic diagnosing device which has a receiving frequency selection part. The figure which shows the frequency characteristic of the echo signal from contrast agent A and contrast agent B.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Ultrasonic probe 12 ... Pulser circuit 13 ... Amplifier 14 ... Signal processing part 15 ... Image storage part 16 ... Image composition part 17 ... Display processing part 18 ... Monitor 19 ... Control part 20 ... Input part 21 ... Setting storage part 22 ... Pulser voltage control unit 23 ... biological signal measurement unit 24 ... reception frequency selection unit

Claims (3)

In an ultrasonic diagnostic apparatus for acquiring blood flow information inside a subject by transmitting and receiving ultrasonic waves to a predetermined part of the subject into which a contrast agent is introduced,
a) a sound pressure condition storage means for storing a sound pressure condition of a transmission ultrasonic wave corresponding to a plurality of types of contrast agents;
b) sequence storage means for storing a combination of sound pressure conditions selected from a plurality of sound pressure conditions stored in the sound pressure condition storage means, and a transmission sequence that determines the execution order;
c) sound pressure control means for controlling the sound pressure of the transmission ultrasonic wave according to the transmission sequence stored by the sequence storage means;
An ultrasonic diagnostic apparatus comprising: Furthermore,
d) image storage means for storing ultrasonic images taken according to the transmission sequence according to sound pressure conditions at the time of shooting;
e) image synthesizing means for computing and synthesizing each ultrasonic image stored by the image storage means;
The ultrasonic diagnostic apparatus according to claim 1, further comprising: Furthermore,
f) a biological signal measuring means for measuring the biological signal of the subject;
The ultrasonic diagnostic apparatus according to claim 2, wherein the image synthesizing unit performs arithmetic synthesis by synchronizing each ultrasonic image based on the biological signal.

Images