JP2008220662A - Ultrasonic diagnostic apparatus and control program therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ultrasonic diagnostic apparatus and the like which can easily grasp the three-dimensional positional relationship among a Doppler measurement sound ray, a blood vessel, and a blood flow measurement site when blood flow measurement is performed by an ultrasonic Doppler method.
A clipping image in which data in front of a Doppler measurement sound ray L and a sampling marker M as viewed from an observer is clipped is automatically generated and displayed. The sampling marker position, the direction of the clipping image, and the clipping range can be arbitrarily changed. By observing the clipping image, it is possible to easily visually recognize the positional relationship between the Doppler measurement sound ray L, the sampling marker M, and the blood vessel running in the horizontal direction of the image and the depth direction of the image as viewed from the observer. A suitable sampling marker position (Doppler measurement position) can be set.
[Selection] Figure 6

Description

  The present invention relates to an ultrasonic diagnostic apparatus having a function of facilitating the visual recognition of a blood flow measurement site in a diagnosis such as in-vivo blood flow measurement by an ultrasonic Doppler method using an ultrasonic diagnostic apparatus capable of real-time three-dimensional scanning. About.

  An ultrasonic diagnostic apparatus is a medical imaging device that non-invasively obtains a tomographic image of soft tissue in a living body from a body surface by an ultrasonic pulse reflection method. Compared to other medical imaging equipment, this ultrasonic diagnostic device has features such as small size, low cost, no exposure to X-rays, high safety, blood flow imaging, etc., and the heart, abdomen, urology, Widely used in obstetrics and gynecology. In particular, in recent years, real-time three-dimensional ultrasound images can be taken due to the speeding up of computers.

  When using this ultrasonic diagnostic apparatus to measure blood flow in a blood vessel or a heart chamber by an ultrasonic Doppler method, it is necessary to set a blood flow measurement site. Several methods for guiding the setting of the blood flow measurement site have been proposed in recent years. For example, when measuring the blood flow in the left ventricular cavity, as shown in FIG. 8 (b), the blood flow from the left ventricular cavity through the aortic valve while observing the drawn two-dimensional cross section in the heart cavity. A sampling marker is artificially set at the position where it flows into the aorta. Thereafter, the Doppler waveform shown in FIG. 8A can be acquired by performing blood flow measurement at the set sampling marker position by the ultrasonic Doppler method.

In addition, as a well-known document relevant to this application, there exist the following, for example.
Japanese Patent Laid-Open No. 10-311367

  However, when blood flow measurement is performed by an ultrasonic Doppler method using a conventional ultrasonic diagnostic apparatus, for example, there are the following problems.

  First, an image used for setting a sampling marker is usually a two-dimensional cross-sectional image. On the other hand, blood vessels and the like in the heart organ and liver organ travel three-dimensionally. Therefore, it is not always possible to display the blood vessel running in a cross section where the position of the blood vessel or the like of the target measurement site can be visually recognized satisfactorily, but the blood flow measurement site (sampling marker position), the blood flow direction, the blood vessel running status, the Doppler It is extremely difficult to grasp the positional relationship between measurement sound rays. Therefore, the operator must set the sampling marker position after grasping the traveling state while following the blood vessel by rolling or rotating the two-dimensional tomographic plane (ultrasonic scanning plane). In particular, the Doppler measurement sound ray is displayed as a line. For this reason, when using a three-dimensional image for setting the sampling marker, it is extremely difficult to grasp the positional relationship with the tissue or the like in the back or near the Doppler measurement sound ray.

  In the ultrasonic Doppler method, it is necessary to ensure an angle (usually 60 degrees or less) between the ultrasonic sound ray and the blood vessel traveling direction (flow direction of blood flow) that does not impair the Doppler shift detection degree. Therefore, at the time of imaging, the operator grasps the positional relationship between the intracardiac structure, the blood vessel running condition, the blood flow direction, and the blood flow measurement target region, and sets the angle between the Doppler measurement sound ray and the blood vessel running direction. However, the human burden is tremendous.

  The present invention has been made in view of the above circumstances. When blood flow measurement is performed by the ultrasonic Doppler method, the three-dimensional positional relationship among the Doppler measurement sound ray, blood vessel, and blood flow measurement site is easily grasped. An object is to provide an ultrasonic diagnostic apparatus and a control method thereof.

  In order to achieve the above object, the present invention takes the following measures.

  The first viewpoint of the present invention is that on the volume data acquired by scanning a three-dimensional region including the imaging target with ultrasound, the center of the sound field of the Doppler measurement beam and the preset clipping range angle. Setting means for setting a clipping range, image generating means for generating a three-dimensional image from which the clipping range is cut out based on the volume data and the clipping range, and display means for displaying the three-dimensional image And an ultrasonic diagnostic apparatus.

  According to a second aspect of the present invention, the center of the sound field of the Doppler measurement beam and the clipping set in advance on the volume data acquired by scanning the three-dimensional region including the object to be imaged with an ultrasonic wave. A setting function for setting a clipping range based on a range angle, an image generation function for generating a three-dimensional image from which the clipping range has been cut based on the volume data and the clipping range, and displaying the three-dimensional image An ultrasonic diagnostic apparatus control program.

  As described above, according to the present invention, when blood flow measurement is performed by the ultrasonic Doppler method, an ultrasonic diagnostic apparatus that can easily grasp the mutual three-dimensional positional relationship among Doppler measurement sound rays, blood vessels, and blood flow measurement sites, and The control method can be realized.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, components having substantially the same function and configuration are denoted by the same reference numerals, and redundant description will be given only when necessary.

  FIG. 1 shows a block diagram of an ultrasonic diagnostic apparatus 1 according to this embodiment. As shown in the figure, the ultrasonic diagnostic apparatus 1 includes an apparatus main body 2 and an ultrasonic probe 3, and the apparatus main body 2 includes an ultrasonic transmission unit 11, an ultrasonic reception unit 13, a B-mode processing unit 15, Doppler processing unit 16, first memory 17, voxel conversion unit 19, second memory 21, image generation unit 23, image composition unit 25, monitor 27, control processor (CPU) 29, interface unit 31, input unit 33 A storage unit 35 is provided.

  The ultrasonic probe 3 generates ultrasonic waves based on a drive signal from the apparatus body 2 and converts a reflected wave from the subject into an electric signal, a matching layer provided in the piezoelectric vibrator, It has a backing material that prevents the propagation of ultrasonic waves from the piezoelectric vibrator to the rear. When ultrasonic waves are transmitted from the ultrasonic probe 3 to the subject P, the transmitted ultrasonic waves are successively reflected by the discontinuous surface of the acoustic impedance of the body tissue and received by the ultrasonic probe 3 as an echo signal. . The amplitude of this echo signal depends on the difference in acoustic impedance at the discontinuous surface that is supposed to be reflected. In addition, the echo when the transmitted ultrasonic pulse is reflected by the moving blood flow or the surface of the heart wall depends on the velocity component in the ultrasonic transmission direction of the moving body due to the Doppler effect, and the frequency Receive a shift.

  The ultrasonic probe 3 can ultrasonically scan a three-dimensional region of the subject. Therefore, the ultrasonic probe 3 has a configuration in which the transducer is mechanically swung along the direction orthogonal to the arrangement direction and ultrasonically scans a three-dimensional region, or a two-dimensionally arranged two-dimensional vibration element. It has a configuration in which a three-dimensional region is ultrasonically scanned by electrical control. When the former configuration is adopted, since the three-dimensional scanning of the subject is performed by the oscillation circuit, the examiner automatically acquires a plurality of two-dimensional tomographic images simply by bringing the probe body into contact with the subject. can do. The exact distance between the sections can also be detected from the controlled rocking speed. When the latter configuration is adopted, in principle, a three-dimensional region can be ultrasonically scanned in the same time as acquiring a conventional two-dimensional tomographic image.

  Furthermore, the ultrasonic probe 3 has a ring-shaped rotary switch 30 as shown in FIG. By rotating the rotation switch 30, a change instruction such as a clipping range angle δ in a clipping process, which will be described later, and a direction of a three-dimensional image such as a volume rendering image is transmitted to the control processor 29.

  The ultrasonic transmission unit 11 includes a trigger generation circuit, a delay circuit, a pulsar circuit, and the like (not shown). In the pulsar circuit, a rate pulse for forming a transmission ultrasonic wave is repeatedly generated at a predetermined rate frequency fr Hz (period: 1 / fr second). Further, in the delay circuit, a delay time necessary for focusing the ultrasonic wave into a beam shape for each channel and determining the transmission directivity is given to each rate pulse. The trigger generation circuit applies a drive pulse to the probe 3 at a timing based on this rate pulse.

  The ultrasonic receiving unit 13 has an amplifier circuit, an A / D converter, an adder and the like not shown. In the amplifier circuit, the echo signal taken in via the ultrasonic probe 3 is amplified for each channel. In the A / D converter, a delay time necessary for determining the reception directivity is given to the amplified echo signal, and thereafter, an addition process is performed in the adder. By this addition, the reflection component from the direction corresponding to the reception directivity of the echo signal is emphasized, and a comprehensive beam for ultrasonic transmission / reception is formed by the reception directivity and the transmission directivity.

  The B-mode processing unit 15 receives the echo signal from the receiving unit 13, performs logarithmic amplification, envelope detection processing, and the like, and generates data for each frame to which signal strength is assigned for each position. This data is transmitted to the image generation unit 23 and is displayed on the monitor 27 as a B-mode image in which the intensity of the reflected wave is represented by luminance.

  The Doppler processing unit 16 performs frequency analysis on velocity information from the echo signal received from the receiving unit 13, extracts blood flow, tissue, and contrast agent echo components due to the Doppler effect, and obtains blood flow information such as average velocity, dispersion, and power. Ask for multiple points.

  The first memory 17 stores the raw data from the B-mode processing unit 15 or the Doppler processing unit 16 for each frame.

  The voxel conversion unit 19 uses the raw data for each frame recorded in the first memory 17 to generate a plurality of volume data.

  The second memory 21 stores a plurality of volume data generated in the voxel conversion unit 19 together with time information.

  The image generation unit 23 generates an ultrasound diagnostic image as a display image based on various data received from the B-mode processing unit 15 and the Doppler processing unit 16. Further, the image generation unit 23 executes predetermined image processing such as volume rendering using the volume data received from the second memory 21 to generate a three-dimensional image or the like. Further, the image generation unit 23 executes processing according to a clipping function based on the Doppler measurement sound ray described later (clipping processing based on the Doppler measurement sound ray) under the control of the control processor 29. The data before entering the image generation unit 23 may be referred to as “raw data”.

  The image synthesizing unit 25 synthesizes the image received from the image generating unit 23 together with character information of various parameters, scales, etc., and outputs it as a video signal to the monitor 27.

  The monitor 27 is based on the video signal from the apparatus main body 2 and morphological information (B mode image) in the living body, blood flow information (average velocity image, dispersion image, power image, etc.), Doppler measurement sound ray to be described later A volume rendering image or the like that has been subjected to clipping processing based on the above is displayed in a predetermined form.

  The control processor 29 has a function as an information processing apparatus (computer) and controls the operation of the entire ultrasonic diagnostic apparatus. The control processor 29 reads out from the storage unit 35 a dedicated program for realizing a clipping function based on the Doppler measurement sound ray, a predetermined scan sequence, a control program for executing image generation / display, and the like. The data is expanded on the memory, and calculations and controls related to various processes are executed.

  The interface unit 31 is an interface related to the input unit 33, a network, and a new external storage device (not shown). Data such as ultrasonic images and analysis results obtained by the apparatus can be transferred by the interface unit 31 to another apparatus via a network.

  The input unit 33 is connected to the apparatus main body 2, and includes various switches, buttons, tracks for incorporating various instructions, conditions, regions of interest (ROI) setting instructions, various image quality condition setting instructions, etc. from the operator into the apparatus main body 2. It has a ball, mouse, keyboard, etc. For example, when the operator operates the end button or the FREEZE button of the input unit 33, the transmission / reception of the ultrasonic wave is ended, and the ultrasonic diagnostic apparatus is temporarily stopped.

  Further, the input unit 33 sets / changes a switch for instructing the start of clipping processing with reference to the Doppler measurement sound ray, a clipping range angle in the processing, a direction of a three-dimensional image obtained by volume rendering, and the like. For example.

  The storage unit 35 is a magnetic disk (floppy (registered trademark) disk, hard disk, etc.), an optical disk (CD-ROM, DVD, etc.), a recording medium such as a semiconductor memory, and a device that reads information recorded on these media. . The storage unit 35 includes transmission / reception conditions, a predetermined scan sequence, a program for realizing a clipping function based on a Doppler measurement sound ray, a control program for executing image generation and display processing, and diagnostic information (patient ID). Doctor's findings, etc.), diagnostic protocol, body mark generation program, various signal data and image data, and other data groups. Data in the storage unit 35 can also be transferred to an external peripheral device via the interface unit 31.

(Clipping function based on Doppler measurement sound ray)
Next, the clipping function based on the Doppler measurement sound ray of the ultrasonic diagnostic apparatus 1 will be described. This function automatically defines a clipping range based on the Doppler measurement sound ray when blood flow measurement is performed by the ultrasonic Doppler method, and a three-dimensional image obtained using volume data in which the range is clipped. By displaying, it is possible to easily grasp the three-dimensional positional relationship among the Doppler measurement sound ray, blood vessel, and blood flow measurement site.

  In the present embodiment, for the sake of specific explanation, the case where the diagnosis target is the heart is taken as an example. However, the technical idea of the present invention is not limited to the image diagnosis of the heart, and can be used, for example, for image diagnosis of the liver and the like.

  FIG. 3 is a flowchart showing the flow of each process executed in the clipping process based on the Doppler measurement sound ray. As shown in the figure, first, when patient information, scan conditions, and the like are input via the input unit 33 (step S1), the control processor 29 executes a three-dimensional volume scan (step S2). The time-series volume data obtained by the three-dimensional volume scan is automatically stored in the second memory 21.

  The volume data acquisition method is not particularly limited. For example, volume scanning may be performed using either a one-dimensional array probe or a two-dimensional array probe, and sub-volume data related to a small area collected in synchronization with the ECG is connected based on an associated trigger. Thus, volume data relating to a desired range may be generated, and a three-dimensional trigger scan that sequentially updates the sub-volume according to time information may be used.

  Next, the image generation unit 23 performs a clipping process on the acquired volume data with reference to the center of the sound field (step S3).

  FIG. 4 is a flowchart showing the flow of clipping processing based on the Doppler measurement sound ray executed by the image generation unit 23. In the figure, first, the image generation unit 23 sets the position of the Doppler measurement sound ray L, the position of the sampling marker M existing on the sound ray, and the clipping range angle δ on the volume data of a predetermined time phase (step). S31). Note that the position of the Doppler measurement sound ray L is based on the sound field center of the Doppler measurement beam set in advance with respect to the ultrasonic scanning region (that is, the volume data) at the time of three-dimensional volume scanning. The position of the marker M can be automatically set based on the focal region of the Doppler measurement beam. Further, the clipping range angle δ is set based on, for example, an initial setting value.

  Next, the image generation unit 23 determines the clipping range CR on the volume data based on the set position of the Doppler measurement sound ray L and the sampling marker M, and the clipping range angle δ (step S32). That is, the image generation unit 23 determines a wedge-shaped area having the Doppler measurement sound ray L as its apex and the clipping range angle δ as its apex angle as the clipping range CR. Therefore, for example, when the volume data is a cone whose apex is the center of the diameter of the ultrasonic irradiation surface S, the clipping range CR is an area as shown in FIG.

  Next, the image generation unit 23 generates volume data from which the clipping range is removed, and performs volume rendering using the volume data, thereby generating an image (clipping image) subjected to clipping processing. The generated clipping image is displayed on the monitor 27 in a predetermined form (step S33). An example of the clipping image displayed in step S33 is shown in FIG.

  Next, when the change of the clipping range angle is instructed, the processing from step S31 to step S33 is repeated using the changed clipping range angle. On the other hand, when at least one of the change of the sampling marker position and the orientation of the clipping image is changed by an instruction from the input unit 33 or the like, the control processor 29 uses the changed sampling marker position or the orientation of the clipping image. Then, the image generation unit 23 and the like are controlled so as to execute the process of step S33 again (step S34).

  Note that the change of the clipping range angle or the change of the orientation of the clipping image can be instructed by using a ring field rotation switch provided in the ultrasonic probe 3. That is, in FIG. 2, for example, when the ring field rotation switch is rotated in the A direction in the clipping range change mode, the clipping range can be expanded, while when the ring field rotation switch is rotated in the B direction. Can reduce the clipping range. For example, when the ring field rotation switch is rotated in the A direction in the image rotation mode, the clipping image can be rotated in the right direction when viewed from the operator, while the ring field rotation switch is rotated in the B direction. In this case, the clipping image can be rotated leftward as viewed from the operator.

  The processes from step S31 to S34 described above (that is, the clipping process in step S3 shown in FIG. 3) are repeatedly executed in real time until a start instruction for Doppler measurement is input from the input unit 33. When an instruction to start Doppler measurement is input, the control processor 29 performs Doppler measurement for the set sampling marker position (that is, Doppler measurement site) (step S5), and the obtained Doppler image and Doppler waveform are obtained. Is displayed in a predetermined form on the monitor 27 (step S6).

(effect)
According to the configuration described above, the following effects can be obtained.

  According to this ultrasonic diagnostic apparatus, it is possible to automatically generate and display a clipping image in which data in front of the Doppler measurement sound ray L and the sampling marker M as viewed from the observer is clipped. In addition, the operator arbitrarily changes the sampling marker position, the orientation of the clipping image, and the clipping range while moving the position of the ultrasonic probe (that is, the position of the Doppler measurement sound ray) while observing the clipping image. be able to. Therefore, the operator sees the Doppler measurement sound ray L, the sampling marker M, and the observer as compared with the case of using the normal volume rendering image as shown in FIG. 7 and the conventional sampling marker display shown in FIG. Thus, it is possible to easily visually recognize the positional relationship between the blood vessel runnings in the left-right direction of the image and the longitudinal direction of the image, and as a result, it is possible to realize a preferable position or range setting of the sampling marker.

  Further, according to the present ultrasonic diagnostic apparatus, by operating the rotating ring provided in the ultrasonic probe 3, the clipping range or the direction of the clipping image in the clipping process based on the Doppler measurement sound ray can be easily and quickly performed. Can be controlled. Therefore, it is not necessary to operate the input unit 33 or to move the line of sight for that purpose, and the burden on the operator in Doppler measurement can be reduced.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Specific examples of modifications are as follows.

  (1) Each function according to the present embodiment can also be realized by installing a program for executing the processing in a computer such as a workstation and developing the program on a memory. At this time, a program capable of causing the computer to execute the technique is stored in a recording medium such as a magnetic disk (floppy (registered trademark) disk, hard disk, etc.), an optical disk (CD-ROM, DVD, etc.), or a semiconductor memory. It can also be distributed.

  (2) In the embodiment described above, an example has been described in which volume data is generated based on raw data for each frame, and clipping processing is executed using the Doppler measurement sound ray as a reference. However, regardless of this, the volume data is generated based on the image data for each frame generated by the image generation unit 23, and the clipping process based on the Doppler measurement sound ray is executed using the volume data. Also good.

  (3) In addition to a clipping image (see FIG. 6) obtained by clipping processing based on the Doppler measurement sound ray as a reference, a normal volume rendering image (see FIG. 7) or a section clipping range is simultaneously provided in a predetermined form. You may make it display. According to such a configuration, it is possible to visually or quantitatively grasp what part or range has been cut out by clipping.

  In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

  As described above, according to the present invention, when blood flow measurement is performed by the ultrasonic Doppler method, an ultrasonic diagnostic apparatus that can easily grasp the mutual three-dimensional positional relationship among Doppler measurement sound rays, blood vessels, and blood flow measurement sites, and The control method can be realized.

FIG. 1 shows a block diagram of an ultrasonic diagnostic apparatus 1 according to this embodiment. FIG. 2 is a diagram showing an example of a ring-shaped rotary switch that the ultrasonic probe 3 has. FIG. 3 is a flowchart showing the flow of each process executed in the clipping process based on the Doppler measurement sound ray. FIG. 4 is a flowchart showing the flow of clipping processing based on the Doppler measurement sound ray executed by the image generation unit 23. FIG. 5 is a diagram showing an example of the clipping range CR set on the volume data based on the positions of the Doppler measurement sound ray L and the sampling marker M, and the clipping range angle δ. FIG. 6 is a diagram showing an example of a clipping image displayed on the monitor 27. FIG. 7 is a diagram for explaining an effect obtained by the ultrasonic diagnostic apparatus according to the present embodiment. FIG. 8 is a diagram for explaining conventional sampling marker display and Doppler measurement using the same.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Ultrasonic diagnostic apparatus, 2 ... Apparatus main body, 3 ... Ultrasonic probe, 11 ... Ultrasonic transmission unit, 13 ... Ultrasonic reception unit, 15 ... B mode processing unit, 16 ... Doppler processing unit, 17 ... 1st Memory, 19 ... Voxel conversion unit, 21 ... Second memory, 23 ... Image generation unit 23 ... Image composition unit, 27 ... Monitor, 29 ... Control processor (CPU), 31 ... Interface unit, 33 ... Input unit, 35 ... Storage unit

Claims (7)

Setting that sets the clipping range based on the sound field center of the beam for Doppler measurement and the preset clipping range angle on the volume data acquired by scanning the three-dimensional region including the imaging target with ultrasound. Means,
Image generating means for generating a three-dimensional image from which the clipping range is cut out based on the volume data and the clipping range;
Display means for displaying the three-dimensional image;
An ultrasonic diagnostic apparatus comprising: Further comprising changing means for changing at least one of the clipping range angle and the orientation of the three-dimensional image,
The image generation means generates the three-dimensional image based on at least one of the changed clipping range angle and the direction of the three-dimensional image;
The ultrasonic diagnostic apparatus according to claim 1.   The ultrasonic diagnostic apparatus according to claim 2, wherein the changing unit is a switch provided in an ultrasonic probe used for acquiring the volume data.   The ultrasonic diagnostic apparatus according to claim 3, wherein the switch provided on the ultrasonic probe is a rotary type. The image generation means generates a three-dimensional image in which the clipping range is not cut based on the volume data,
The display means simultaneously displays the three-dimensional image from which the clipping range is cut off and the three-dimensional image from which the clipping range is not cut;
The ultrasonic diagnostic apparatus according to any one of claims 1 to 4, wherein:   The ultrasonic diagnostic apparatus according to claim 1, wherein the display unit displays the clipping range angle together with the three-dimensional image from which the clipping range is cut out. On the computer,
Setting that sets the clipping range based on the center of the sound field of the Doppler measurement beam and the preset clipping range angle on the volume data acquired by scanning the 3D area including the imaging target with ultrasound. Function and
Based on the volume data and the clipping range, an image generation function for generating a three-dimensional image from which the clipping range has been cut off;
A display function for displaying the three-dimensional image;
An ultrasonic diagnostic apparatus control program comprising:

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