JP2000135217A - 3D ultrasonic diagnostic equipment - Google Patents

Abstract

(57) [Summary] An object of the present invention is to improve both spatial resolution and temporal resolution in an ultrasonic diagnostic apparatus for three-dimensionally displaying the inside of a subject. The present invention relates to a three-dimensional ultrasonic diagnostic apparatus capable of three-dimensionally scanning a three-dimensional region in a subject with ultrasonic waves.
Only two arbitrary tomographic planes in the two-dimensional scanable area are scanned with ultrasonic waves to generate two images corresponding to the two tomographic planes,
It is characterized in that these two images are position-aligned according to the positional relationship between the two tomographic planes, and are synthesized and displayed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional ultrasonic diagnostic apparatus for three-dimensionally imaging the inside of a subject, and more particularly to a technique for improving real-time performance.

[0002]

2. Description of the Related Art In recent years, a two-dimensional array type ultrasonic probe or the like is used to scan a three-dimensional region inside a subject with ultrasonic waves (called a three-dimensional scan or a volume scan). Various attempts have been made to display a three-dimensional image, and a system that performs three-dimensional scanning in real time and simultaneously displays a plurality of tomographic images in real time has been announced.

In a conventional ultrasonic diagnostic apparatus for displaying a two-dimensional tomographic image, an ultrasonic wave may be moved in a tomographic plane.
In three dimensions, it is necessary to move ultrasonic waves vertically and horizontally in a three-dimensional area. In order to reproduce the natural movement of the internal tissue while maintaining the real-time property, the time required for scanning through the three-dimensional area is reduced, and the time resolution (volume rate), that is, three-dimensional It is necessary to increase the number of times of scanning the area to about 30 times per second as in the case of the two-dimensional scanning.

As is well known, the propagation speed (sound speed) of an ultrasonic wave in a human body is almost constant, and a basic system of ultrasonic diagnosis for obtaining image information of the inside of a human body by scanning an ultrasonic wave is a unit time. The number of ultrasonic scanning lines that can be scanned around depends largely on the above physical limit. In other words, the time required for one transmission / reception of an ultrasonic wave is absolutely determined by the depth of field and the above-mentioned propagation speed, so that the number of ultrasonic scanning lines per second is almost irrespective of two dimensions or three dimensions. It is fixed.

[0005] Therefore, in order to realize real-time three-dimensional scanning, the spatial resolution (density of ultrasonic scanning lines) must be reduced and the image quality must be tolerated. In order to dramatically increase the number of ultrasonic scanning lines per second, adoption of high-speed means such as multidirectional simultaneous reception known as a digital beamformer has been studied. At present, only a few transmissions are received in one transmission, and at present, it is impossible to satisfy both the time resolution and the spatial resolution in a practical range in three-dimensional scanning.

[0006]

As described above, when the ultrasonic scanning is expanded from the conventional two-dimensional tomographic plane to the three-dimensional volume area due to the physical restriction by the sound speed of the ultrasonic wave, the tomographic plane to be displayed is displayed. In comparison, the fundamental problem that the density of the ultrasonic scanning lines decreases and image degradation occurs occurs. That is, in ultrasonic diagnosis, a high-quality image has conventionally been required, and it is a serious problem that the original image information becomes sparse by performing three-dimensional display.

[0007] Further, ultrasonic diagnostic images mainly use a display method of expressing differences in tissue properties by luminance. It is difficult to display all of this image information three-dimensionally, and an appropriate three-dimensional display method has been established. There is another problem.

Further, there is a great demand for simultaneously acquiring a B-mode image and a blood flow image of an ultrasonic diagnostic apparatus, reconstructing each as a three-dimensional image, and displaying the combined image, and there are examples in which an actual display method has been proposed. Even in such a case, the three-dimensional display of the ultrasonic B-mode image and the blood flow image can be used to express the three-dimensional display in order to sufficiently observe the mutual positional relationship and the individual three-dimensional shape. It was scarce and not enough.

Further, when displaying an ultrasonic image three-dimensionally, unlike an image diagnostic apparatus such as X-ray CT or MRI, the display area of the acquired image is small, and the display shape is determined by the scanning method of the ultrasonic probe. Because of the large number, the three-dimensional image created by reconstructing the collected image also has a variety of directions and shapes, and there is a problem that the user tends to lose the orientation of the displayed three-dimensional image.

The present invention has been made in view of such problems of the conventional real-time three-dimensional ultrasonic diagnostic apparatus. That is, an object of the present invention is to improve both the spatial resolution and the temporal resolution in an ultrasonic diagnostic apparatus that displays the inside of a subject three-dimensionally. More specifically, when displaying an ultrasonic image three-dimensionally, it is easy for an observer to intuitively recognize the morphological information inside the living body, and to realize a high-quality display image. To display an ultrasonic image three-dimensionally in an easy-to-understand manner,
Further, it is to make it easy for an observer to recognize the positional relationship between the displayed three-dimensional images. Furthermore, a B-mode image and a blood flow image are simultaneously collected, and reconstructed and synthesized as a three-dimensional image. When displaying, it is to make it easy to grasp a mutual positional relationship and an individual three-dimensional shape.

[0011]

According to the present invention, there is provided a three-dimensional ultrasonic diagnostic apparatus capable of three-dimensionally scanning a three-dimensional area in a subject with an ultrasonic wave. Scanning two tomographic planes with ultrasonic waves to generate two images corresponding to the two tomographic planes, aligning the two images in accordance with the positional relationship between the two tomographic planes, and displaying the combined images. Features. (2) The present invention relates to a three-dimensional ultrasonic diagnostic apparatus capable of scanning a three-dimensional region in a subject with ultrasonic waves, and two-dimensionally scanning an arbitrary tomographic plane in the three-dimensional region with ultrasonic waves. A first display mode for generating and displaying an image corresponding to the surface;
A second display mode in which an arbitrary local area in the three-dimensional area is three-dimensionally scanned with ultrasonic waves to generate and display a three-dimensional image corresponding to the local area; and the first and second display modes. A third display mode for simultaneously displaying the image corresponding to the tomographic plane and the three-dimensional image can be selected by combining display modes. (3) According to the present invention, in the apparatus of (1), a three-dimensional scannable area is three-dimensionally displayed as a schematic figure, and the two images are displayed on the tomographic plane in the schematic figure. Are combined and displayed according to the position. (4) The apparatus according to (2), wherein the three-dimensionally operable three-dimensional operation is performed in each of the first and third scanning modes.
It is characterized in that the dimensional area is displayed three-dimensionally as a schematic figure, and the two images are displayed on the schematic figure in a position-matched manner according to the positions of the respective tomographic planes. (5) The present invention is characterized in that, in the apparatus according to (2), in a third scanning mode, a scanning ratio between the first scanning mode and the second scanning mode can be changed. (6) The present invention relates to the apparatus (1) or (2),
A graphic for assisting the setting of the two tomographic planes in the dimensional scanable area is displayed. (7) In the apparatus according to (2), in the second and third scanning modes, a schematic figure representing the local region and the three-dimensional image are displayed in a positional correspondence with each other. It is characterized by the following. (8) In the apparatus according to (2), in the second and third scanning modes, a schematic graphic representing the local region is displayed, and a three-dimensional image corresponding to the local region is displayed. It is characterized in that it is displayed outside a schematic figure. (9) According to the present invention, in the apparatus of (1) or (2), two tomographic planes actually scanned by ultrasonic waves are set so as to intersect at a central axis of the three-dimensional scannable area. Features. (10) The present invention relates to the apparatus of (1) or (2),
It is characterized in that a schematic figure representing a three-dimensional scanable area and a schematic figure representing an ultrasonic probe are displayed three-dimensionally with their directions aligned. (11) In the apparatus according to (2), in the third scanning mode, the image corresponding to the tomographic plane is an ultrasonic image based on a signal derived from tissue, and the three-dimensional image is derived from tissue. Or an ultrasonic image based on a signal derived from a blood flow. (12) In the apparatus according to (2), in the third scanning mode, the display transparency of the image corresponding to the tomographic plane and the display transparency of the three-dimensional image are individually set. It is characterized by being possible. (13) The present invention is characterized in that, in the device of (2), support information for supporting a change in the size and position of the local region is displayed. (14) The apparatus according to (13), wherein the support information includes a C-mode image relating to a tomographic plane at an arbitrary depth substantially orthogonal to the central axis of the three-dimensional area. (15) The present invention is characterized in that, in the device of (2), the expected position on the display of the three-dimensional image can be changed. (16) The apparatus according to (14), wherein the tomographic plane of the C-mode image is automatically moved up and down along the central axis of the three-dimensional area. (17) The present invention provides the device according to (1) or (2),
At least one of the two tomographic planes is automatically moved at arbitrary spatial and temporal intervals. (18) The present invention is characterized in that, in the apparatus according to (17), at least one of the two tomographic planes is automatically rotated about a center axis of the three-dimensional scanable area as a rotation center. (19) The present invention provides the apparatus according to (17), wherein the two tomographic planes are arranged along a direction substantially orthogonal to at least one of the two tomographic planes.
At least one of the two fault planes is automatically moved. (20) According to the present invention, a three-dimensional region in a subject is
In a three-dimensional ultrasonic diagnostic apparatus capable of three-dimensional scanning,
Scan any tomographic plane within the dimensional scanable area with ultrasonic waves,
A means for generating an ultrasonic image in the subject based on the scanning information; a means for generating a graphic image representing the three-dimensional scannable area; Means for synthesizing and displaying an ultrasonic image of the cross section. (Operation) According to the present invention, since only two arbitrary tomographic planes in the three-dimensional scanable area are scanned by the ultrasonic wave, the time required for scanning can be significantly reduced as compared with scanning the entire three-dimensional area. . Further, since two images corresponding to the two tomographic planes are aligned and displayed in accordance with the positional relationship between the two tomographic planes, three-dimensional information such as a form inside a living body can be intuitively recognized. . Therefore, a three-dimensional image is
It is possible to obtain high temporal resolution and high spatial resolution, that is, high image quality.

According to the present invention, only two arbitrary tomographic planes in a three-dimensional area are two-dimensionally scanned by ultrasonic waves.
Since three-dimensional scanning is limited to a local area,
A two-dimensional image can be obtained more easily and in detail with high temporal resolution and high spatial resolution.

Further, according to the present invention, the three-dimensional scannable area is three-dimensionally displayed as a schematic figure, and two images are positioned on the schematic figure according to the position of each tomographic plane. Since the images are aligned and synthesized and displayed, it is possible to more easily recognize the three-dimensional structural relationship between the two images.

Further, according to the present invention, since the scanning frequency between the tomographic plane and the three-dimensional area can be arbitrarily adjusted, the spatial resolution and the temporal resolution of the tomographic plane and the three-dimensional image can be optimized.

Further, in the present invention, a schematic figure representing a three-dimensional scanable area and a schematic figure representing an ultrasonic probe are displayed three-dimensionally with their orientations aligned. It is easy to intuitively grasp the orientation of the displayed three-dimensional image.

Further, according to the present invention, a local region for performing three-dimensional scanning can be set by using a C-mode image. Therefore, the local region is optimized and reduced to a minimum size, thereby improving the time resolution. Can be planned.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 schematically shows the configuration of the ultrasonic diagnostic apparatus of the present embodiment. This apparatus includes an ultrasonic probe 1, an apparatus main body 12, a display 7, and a scanning panel 11. The ultrasonic probe 1 includes a plurality of vibrating elements for mutually converting an electric signal and an acoustic signal so that a three-dimensional region inside the subject can be electronically scanned at a high speed by ultrasonic waves. A two-dimensional array type arranged in a matrix is employed.

The apparatus main body 12 includes a transmission / reception unit 2, a digital beam former switch unit 3, an image processing unit 13, a host CPU 7, and
And a display unit 9. The transmission / reception unit 2 includes a transmission / reception switch (T
/ R SW) 23, a transmitter (Transmitter) 21, and a preamplifier (Pre AMP) 22. Switch 23
When transmitting ultrasonic waves, the ultrasonic probe 1
Is connected, and a preamplifier 22 is connected to the ultrasonic probe 1 when receiving an echo.

Although not shown, the transmitter 21 includes a clock generator, a frequency divider, a transmission delay circuit, and a pulser, and converts the clock pulse generated by the clock generator into a rate pulse of, for example, about 6 KHz by the frequency divider. The rate pulse is supplied to a pulser through a transmission delay circuit to generate a high-frequency voltage pulse, thereby driving the vibrating element, that is, mechanically vibrating. The ultrasonic wave generated in this way is reflected at the boundary of the acoustic impedance in the subject, returns to the ultrasonic probe 1, and mechanically vibrates the vibration element. As a result, an electric signal is individually generated for each vibration element. This electric signal is amplified by the preamplifier 22 and then sent to the digital beamformer unit 3.
The delay and addition are performed. As a result, a signal having directivity (received signal) is generated.

It is to be noted that the time required to scan the three-dimensional region inside the subject with ultrasonic waves, that is, the time required for three-dimensional scanning (also referred to as volume scanning) is reduced, and the time resolution, ie, three-dimensional per second, is reduced. In order to improve the number of scans (volume rate) of the region and promote real-time performance, the ultrasonic beam is intentionally made thicker by delay control of a voltage pulse applied to each vibrating element. In order to generate a plurality of (here, n) reception signals having different directivities each time this thick ultrasonic beam is transmitted once, that is, to realize so-called multidirectional simultaneous reception, a digital beamformer unit is used. 3 includes a plurality (here, n
) Of digital beamformers 311 to 31n, and perform phasing addition with different phase shift patterns.

The image processing unit 13 is equipped with four processors 4, 5, 6, and 8 connected to a bus. The application processor 6 mainly has display modes and processing functions necessary for measurement. In addition, the echo processor 4 generates B-mode image data that provides morphological information of the tissue based on the received signal from the digital beamformer unit 3. Further, the echo processor 4 extracts a harmonic component (a frequency component that is an integral multiple of the fundamental frequency) contained in the received signal, and provides morphological information of the tissue more clearly based on the harmonic component. Generate tissue harmonic image data.

The Doppler processor 5 is a unit for realizing a so-called color flow mapping (CFM).
First, a received signal from the digital beamformer unit 3 is detected in quadrature phase to extract a frequency-shifted Doppler signal. From the extracted Doppler signal, only a specific frequency component is passed through an MTI filter, and the passed signal is extracted. Is calculated by an autocorrelator, and the arithmetic unit calculates the average speed, variance, and power from this frequency. By adjusting the pass band of the MTI filter, general CFM image data mainly imaging the tissue and blood flow velocity and tissue Doppler image data mainly imaging the tissue shape such as myocardium can be obtained. It can be generated selectively. Also, the Doppler processor 5
Power Doppler image data that visualizes the shape of tissue and blood flow from power can be generated.

Three-dimensional processor (three-dimensional processor) 8
Is to generate three-dimensional image data as described later from arbitrary image data among the above-described B-mode image data, tissue harmonic image data, CFM image data, tissue Doppler image data, and power Doppler image data. Is available.

Further, the three-dimensional processor 8 is configured to perform any of the B-mode image data, the tissue harmonic image data, and the power Doppler image data based on arbitrary image data.
It is possible to generate three-dimensional image data as described later.

Further, the three-dimensional processor 8 is capable of constructing a figure, for example, a wire frame model, which schematically represents the shape of a three-dimensional area inside the subject which can be three-dimensionally scanned. The three-dimensional processor 8 is necessary for realizing various displays as described below, such as combining the B-mode image data with the wireframe model by performing oblique processing as necessary and aligning and synthesizing the data. Processing can be performed. This three-dimensional processor 8
Is displayed on the display 7 via the display unit 9. (Basic Scanning and Three-Dimensional Display Screen Configuration) In the present embodiment, the basis of a method for displaying tomographic image data such as B-mode image data in three dimensions is based on a three-dimensional scanable area. As shown in FIG. 2A, the ultrasonic probe 1 is schematically displayed by a wire frame model having the ultrasonic radiation surface as a base point. Then, as shown in FIG. 2B, any two tomographic planes (A plane, A plane) intersecting from the center of the ultrasonic probe 1 at the center axis of the three-dimensional area in the three-dimensional scanable area.
Two pieces of tomographic image data obtained by alternately two-dimensionally scanning only the B surface) are appropriately subjected to oblique processing, are aligned with the wire frame model, are combined, and displayed as shown in FIG. This alignment is a factor of 2 in the wireframe model.
A tomographic image is synthesized and displayed at a position corresponding to the tomographic image obtained by performing the dimensional scanning. In the lower right column of the display screen, the two tomographic images to be combined and displayed on the wire frame model are separately displayed as a two-dimensional image over the entire surface.

In order to make it easy to understand the positional relationship between the two tomographic planes to be two-dimensionally scanned and to easily set the two tomographic planes to be two-dimensionally scanned, a three-dimensional image is displayed in the upper right column of the screen. A guide figure is displayed as if the scannable area was viewed from the probe side as a bird. By operating the guide graphic with the pointing device of the scanning panel 11, the two tomographic planes can be arbitrarily changed (moved). When the tomographic plane is changed, the driving condition of the probe 1 by the transmission / reception unit 2 is changed, whereby the two-dimensional scanning tomographic plane by the ultrasonic wave is automatically changed.

As described above, according to the present embodiment, only two arbitrary tomographic planes in the three-dimensional scanable area are scanned by the ultrasonic wave. In consideration of the above, it is possible to significantly improve the ultrasonic scanning line density and obtain a high spatial resolution, that is, a high image quality. Further, two tomographic images corresponding to two intersecting tomographic planes are synthesized in a form reflecting the actual position,
Since it fits into a wireframe model that schematically represents a three-dimensional scannable area, it is intuitively recognizing three-dimensional information such as the form inside a living body, compared to a case where two tomographic images are simply displayed side by side. can do. Further, by manually moving the two tomographic planes, the morphology of the tissue and the flow of the blood flow can be more three-dimensionally understood. (Automatic movement of tomographic plane) By automatically moving at least one of the two tomographic planes, a three-dimensional understanding of the morphology of the tissue and the flow of blood flow can be further promoted.
4 and 5 show examples of this display. A menu for setting automatic movement conditions is displayed in a lower right column of the screen. On this setting menu, the fault plane that moves automatically
(Scan Plane) is designated as one or both of the A plane and B plane, the scanning method (Scan type) is selectively designated from method a and method b, and the moving range of the tomographic plane (scan Aria) is specified. The angle can be specified, the moving interval (Scan pitch) of the tomographic plane can be arbitrarily specified, and the moving speed (Scan speed) of the tomographic plane can be arbitrarily specified. The transmission / reception unit 2 automatically moves the tomographic plane to be two-dimensionally scanned in accordance with the set movement conditions, and performs processing so that the display unit 10 moves the tomographic image with respect to the wire frame model in accordance with the movement.

FIG. 4 shows the movement of the tomographic plane by the scanning method a. In this method a, the tomographic plane is automatically rotated around the center axis of the three-dimensional scannable area as the center of rotation. It has become. FIG. 5 shows how the tomographic plane is moved by the scanning method b.
In, the tomographic plane automatically moves along a direction substantially orthogonal to the tomographic plane to be moved.

If the tomographic plane is automatically moved in this way, after the ultrasonic probe 1 is applied to the surface of the subject, two tomographic planes passing through the central axis are displayed in real time, and an automatic movement button is displayed. When the button is pressed, the display is such that the ultrasonic two-dimensional scanning tomographic plane moves in the three-dimensional scanable area and the tomographic image continuously moves in the wire frame model indicating the three-dimensional scanable area. Note that the moving method can be selected from a case of moving in only one direction and a case of reciprocating.

Next, a specific operation of the ultrasonic diagnostic apparatus according to the present embodiment will be described. The ultrasonic diagnostic apparatus according to the present embodiment can selectively operate in three types of scanning modes. The display of FIG. 3, FIG. 4, or FIG. Hereinafter, these three types of scanning modes will be described in order. (First Scan Mode) FIG. 6 shows an example of a display screen in the first scan mode. In the first scanning mode, it is preferable to provide a B-mode image or a CFM image of two orthogonal tomographic planes corresponding to the orthogonal vibrating element array of the two-dimensional array probe 1. The scanning is very similar to the case of scanning two orthogonal tomographic planes using a conventional biplane probe, and corresponds to a scanning mode applied to the two-dimensional array probe 1.

In the first scanning mode, only two tomographic planes are two-dimensionally scanned from the three-dimensionally scannable area in the subject, so this is not a means for directly obtaining a three-dimensional image in the original sense. . However, when performing three-dimensional scanning (N
The scanning range is smaller than (× M scanning lines) (N × 2 scanning lines), so that although it is a limited tomographic plane of two, the time resolution is set to be high enough not to impair the real-time property much. It is possible to provide high image quality (high spatial resolution).

Therefore, the first scanning mode can be preferably used as a guide for the operator to position the probe with respect to the subject as a pre-means for obtaining a three-dimensional image. The outline of the execution procedure of the operation in this mode will be described below.

The operator selects the first scanning mode by a predetermined selection from the operation panel 11. Operation panel 11
Is input to the host CPU 10 via the bus. The host CPU 10 sends the first transmission / reception unit 2 and the beam former unit 3 via the bus to the first unit.
Output a control signal corresponding to the scan mode. Thus, scanning corresponding to the first scanning mode is performed. Further, the host CPU 10 outputs a control signal for realizing signal processing corresponding to the first scanning mode to the echo processor 4, the Doppler processor 5, the three-dimensional processor 8, and the display unit 9 via the bus.

Here, the echo processor 4 generates an ultrasonic image signal (base signal of the B-mode image) derived from the tissue from the received signal, and the Doppler processor 5 generates the ultrasonic signal from the received signal on the same position in time series. Ultrasound image signal derived from blood flow (C
An FM image base signal) is generated. 3D processor 8
Performs an operation of projecting three-dimensional coordinate data based on the position of the probe 1 onto a two-dimensional image for each of the following display elements, and performs conversion for image display.

Display elements: a wire frame model representing the outer shape of the three-dimensional scannable area, a tomographic image of the tomographic plane A (B-mode image or the like), a tomographic image of the tomographic plane B (B-mode image or the like), a probe figure ( With respect to the probe graphic and the wireframe model of the three-dimensional scannable area, a predetermined expected position is set for the probe 1 so as to be converted into a projection image. The tomographic image of the tomographic plane A and the tomographic image of the tomographic plane B obtained from the base signal of the B-mode image or the base signal of the CFM image are also converted into projection images using the same expected positions. The position setting of the tomographic planes A and B is performed based on the values of the host CPU 10 in the initial state.

When the operator wants to move the tomographic plane, it is realized by updating the value in the initial state to a predetermined value by a predetermined selection from the operation panel 11. The display unit 9 generates image data by superimposing the plurality of display elements, and the monitor 7 displays an ultrasonic image.

FIG. 6 is a display example of a typical main scan mode when the left ventricle of the heart is obtained from the apex. While observing the display as shown in FIG. 6 in real time, the operator adjusts the position while moving or raising the probe 1 while searching for an area to be three-dimensionally viewed, and also adjusts the position of the tomographic plane A , B, etc., to confirm that the area to be surely viewed is covered. (Second scanning mode) The second scanning mode includes a local area (3D-ROI) that forms a part of the three-dimensional scanable area,
More specifically, a three-dimensional local region surrounded by a B-mode image or a CFM image having two orthogonal cross sections corresponding to the orthogonal element arrangement of the two-dimensional array probe 1 set in the first scanning mode. Is a preferred scanning mode to provide a three-dimensional ultrasound image corresponding to.

In the third scanning mode, three-dimensional scanning (N'.times.M 'scanning lines) is performed.
The real-time property tends to be lower than in the first scanning mode (N × 2 scanning lines) in which only two tomographic planes are extracted from the dimensional space. However, the region where the three-dimensional scanning is performed is limited to a local region of an appropriate size (N ′ <N, 2 <M ′ <
By performing M), it is possible to minimize the decrease in the real-time property, and it is possible to provide three-dimensional information that cannot be obtained in the first scanning mode.

Therefore, in the third scanning mode, it is preferable that the operator switches the scanning mode setting to obtain a three-dimensional image after the display in the first scanning mode for guiding the positioning. is there.

The outline of the execution procedure of the operation in the third scanning mode will be described below. The operator makes a transition to this mode by a predetermined selection from the operation panel 11. The following operation procedure is basically the same as the first scanning mode. here,
The three-dimensional processor 8 in the main scanning mode performs an operation for projecting three-dimensional coordinate data based on the probe position onto a two-dimensional image for each of the following display elements, and displays the image. In addition to the basic processing for converting coordinates and size, especially for a three-dimensional image, (1) setting of transparency for expressing perspective, (2) processing for maximum intensity projection called MIP, (3) 3.) generally known three-dimensional image reconstruction processing such as pre-processing of contour extraction and post-processing of volume rendering.

Examples of display elements: figures such as a wire frame model (3D-ROI) representing the outline of a local area, three-dimensional ultrasonic images, probe figures (including scanning marks), probe figures and three-dimensional The wireframe model of the scannable area may or may not be displayed, but the display operation is the same as in the first scan mode. For a graphic in a local area where three-dimensional scanning is performed, conversion to a projected image is performed by setting a predetermined expected position for the probe.

A three-dimensional ultrasonic image obtained from a base signal of a B-mode image or a base signal of a CFM image corresponding to the inside of a local area where three-dimensional scanning is performed is converted into a projection image using the same expected position. Done. The setting of these expected positions is performed based on the values of the initial state of the host CPU 10. When the operator wants to move the expected position, the value in the initial state is updated to a predetermined value by a predetermined control from the operation panel 11. When the operator wants to move the position of the region of interest, the same operation is realized through a predetermined switch control different from the expected position.

FIG. 7 shows a display example of the third typical scan mode for mitral valve observation when the left ventricle of the heart is obtained from the apex. The three-dimensional image (FIG. 7B)
Although it may be displayed inside the D-ROI, as shown in FIG.
It may be displayed separately outside the D-ROI. When displayed externally, the figure itself such as the 3D-ROI serves as a guide for grasping the orientation, which facilitates grasping the position of the cut-out three-dimensional image.
Further, regarding the cut-out three-dimensional image, even if there is a portion that is hidden at the default expected position and is difficult to see,
Since the rotation of the expected position and the enlargement of the image itself can be arbitrarily performed by the operation of the dimensional processor 8, the visibility is improved.

While observing the display as shown in FIG. 7 in real time, the operator records a moving image on a moving image recording medium such as a video, selects a desired time phase, stops scanning by a freeze operation, and then stops. Images can be recorded on a recording medium such as a photograph. Since the three-dimensional image can be provided in real time, the diagnosis time and accuracy of a stress echo useful for examining ischemic heart disease, for example, are improved. In the conventional stress echo, it was necessary to record a plurality of tomographic images one after another in a short time in order to evaluate three-dimensional myocardial behavior only with tomographic images. This is because the positioning can be easily performed in the scanning mode, and the originally desired three-dimensional image can be recorded in real time in the second scanning mode. (Third scanning mode) The third scanning mode is a B mode image or CFM image of two orthogonal cross sections corresponding to the orthogonal element arrangement of the two-dimensional array type probe 1 set in the first scanning mode. And 3 surrounded by two orthogonal cross sections
Providing a three-dimensional ultrasound image contained in a dimensional space is a preferred scanning mode. The main scanning mode is a mode in which the first scanning mode and the second scanning mode are combined, and is obtained by adding display information of two tomographic images to the display of the above-described second scanning mode. is there. When the main scanning mode is used, the following two types are roughly selected according to the purpose.
There are provided usage forms.

On the other hand, the main focus is on taking advantage of the advantage of “high image quality and high frame number” in the first scanning mode, and after the display in the first scanning mode as a guide for positioning, the operator performs three-dimensional operation. It is preferable to switch the scan mode setting to the main scan mode in order to obtain a proper image. For example, it is suitable for use at the time of the first consultation in which the operator does not have a priori information on positioning.

On the other hand, the main scanning mode is selected from the beginning without going through the setup of switching the scanning mode. For example, the operator has a priori information on the subject as in follow-up observation. Suitable for use when

The outline of the execution procedure of the operation in the third scanning mode will be described below. The operator makes a transition to the third scanning mode by a predetermined selection from the operation panel 11. The following operation procedure is basically the same as the second scanning mode,
The explanation is omitted. Here, the three-dimensional processor 8 in the main scanning mode performs a predetermined process on each of the following display elements.

Examples of display elements; figures (3D-ROI) such as a wire frame model representing the external shape of a local area, three-dimensional ultrasonic images, probe figures (including scanning marks), and wires in a three-dimensional scanable area FIG. 8 shows a display example of a typical full-scan mode for mitral valve observation in the case where the frame model, the tomographic image of the tomographic plane A, the tomographic image of the tomographic plane B, and the left ventricle of the heart are obtained from the apex. Show. In FIG. 8, the three-dimensional image display is 3D-R
Although it may be displayed inside the OI, as shown in this figure, 3D-RO
I may be displayed outside. 3D-
The ROI itself plays a role as a guide for grasping the orientation, which facilitates grasping the position of the cut-out three-dimensional image. Further, regarding the cut-out three-dimensional image, even if there is a part that is hidden at the default expected position and is difficult to see, the rotation of the expected position and the enlargement of the image itself can be arbitrarily performed by the operation of the three-dimensional processor 8, so that the visibility is improved. improves.

On the other hand, when displaying a three-dimensional image inside the 3D-ROI, two tomographic images A and B
And the three-dimensional image are displayed overlapping, so that the tomographic image and the three-dimensional image are displayed.
Displaying the two-dimensional image while changing the transparency of both is preferable in that the two can be observed separately. As an example, by the operation of the three-dimensional processor 8, normal display is performed on a tomographic image of a part that does not overlap with the three-dimensional image, and transparency of weighting α is given to the tomographic image of a part that overlaps with the three-dimensional image. The three-dimensional image is displayed with a transparency of weighting 1-α. In this way, the tomographic image of the back is displayed through the translucent three-dimensional image even in the portion where the two overlap, and the tomographic image A,
This makes it easier to understand the orientation comparison between B and the three-dimensional image. Of course, if the color map setting of the tomographic image and the color map setting of the three-dimensional image are made different from each other in addition to the setting of the transparency, the effect of separating the two by the color tone is added, so that an effective embodiment can be obtained. . The setting itself of the color map can be realized by providing the function to either the three-dimensional processor 8 or the display unit 9.

It goes without saying that the display examples of the image according to the present invention are not limited to the above-described embodiment, but various modifications can be obtained without departing from the gist thereof.

For example, in the third display mode, FIG.
In the display example shown by B, a B-mode image derived from a tissue is used as a tomographic image, and a three-dimensional display is based on a signal derived from a tissue (MI
P or volume rendering) image, but the tomographic image may be a CFM image derived from blood flow, a CFM image containing tissue motion information called tissue Doppler, or a tissue harmonic. A B-mode image including information depending on the nonlinearity of tissue propagation may be used. The signal that is the basis of the three-dimensional image is also a tomographic image.

At this time, the ultrasonic contrast agent may be administered to the subject, and the information of the contrast agent component may be included in the received signal. The point of the present invention lies in the novel display procedure and display method, and the ultrasonic scanning method related to the display. As another display example of the main scanning mode, FIG. 9 shows a typical display example for diagnosing blood flow in a tumor in a liver.

However, in the third scanning mode, there are cases where, due to various restrictions and diagnostic purposes, combinations of the image modes of the tomographic image and the three-dimensional image are more suitable and non-optimal. Conceivable. For example, this is especially true in the case of diagnosing the heart as shown in FIG. 8, but in many cases, real-time performance is important in an ultrasonic diagnostic apparatus, and therefore a combination in which the number of frames is as large as possible is desirable. In order to obtain a three-dimensional image derived from blood flow, as shown in Attachment 1, in order to provide an appropriate number of frames, it is necessary to limit the size of the local region to be actually three-dimensionally scanned or reduce the scanning line density. It needs to be rough. Here, even in tomographic images, CFM derived from blood flow
Obtaining an image unnecessarily reduces the number of frames, and is not a preferable combination.

In the third scanning mode, the tomographic image is 3
It is more preferable to display the normal B mode as a guide as a guide for giving the orientation of the two-dimensional image when real-time properties are emphasized.

Further, with respect to the scanning sequence of the tomographic image and the three-dimensional image, the scanning ratio between the two-dimensional scanning in the first scanning mode and the three-dimensional scanning in the second scanning mode can be changed. For example, as shown in FIG. 10A, not only a general sequence in which two-dimensional scanning of a tomographic image and three-dimensional scanning of a three-dimensional image are constantly and alternately repeated in a time-division manner, but also a method that emphasizes time resolution. It is also preferable to allocate time by scanning. For example, FIG.
As shown in (b) and (c), three-dimensional scanning is performed most of the time, and tomographic image scanning is performed only occasionally (or only when there is a switch control). Real-time reduction is suppressed. Of course, the real-time property of the tomographic image itself is reduced, but it can function sufficiently as a positional guide. Conversely, in a case where a tomographic image is more important than a three-dimensional image, FIG.
As shown in (e), tomographic image scanning is performed most of the time, and three-dimensional scanning may be performed occasionally (or only when switch control is performed).

FIG. 11 is a diagram for explaining a method of setting a local area (3D-ROI) for performing three-dimensional scanning in the second and third scanning modes. Here, a valve disease will be described as an example. In order to observe the morphology of the valve in three dimensions, 3D-R
It is necessary that the target valve be included in the OI. Therefore, in order to determine the 3D-ROI more easily, a C-mode image at, for example, a half position in the depth direction in the 3D-ROI guide wire is separately displayed (the C-mode surface is 3D-ROI according to the purpose). Can be set to any depth within the guidewire). Note that, as is well known, the C-mode image is a tomographic image on a plane (C-mode plane) substantially orthogonal to the ultrasonic beam.

If the target valve can be captured in the guide C-mode image plane, that is, the valve can be included in the 3D-ROI guidewire. Thus, the 3D-ROI
If a C-mode surface is set in the guide wire and the 3D-ROI guide wire is moved to the scan area in real time using the C-mode image displayed in another area as a guide,
The 3D-ROI including the valve captured in the mode image can be positioned efficiently and reliably. This gives R
Since the OI setting is facilitated, the diagnosis can be smoothly performed.

Conversely, a 3D-ROI guide wire may be installed approximately in the area where the valve is present, and the C-mode plane position may be moved manually or automatically in the vertical direction. In this case, once the valve has been successfully captured in the C-mode image,
3D-
The ROI guidewire is moved to the C-mode plane.

When the 3D-ROI guide wire is set, the C-mode plane is newly moved in the vertical direction, the upper limit and the lower limit to be displayed are marked, and three-dimensional display of only that area is performed. This is effective when it is desired to extract and display only a portion within the region determined by the 3D-ROI guidewire, for example, only the valve here. Simply 3D-R
The height of the OI guidewire should be 3 so that the valve area is well inserted.
Efficiency is better than adjusting by repeatedly adjusting based on the dimensional display image.

Alternatively, the 3D-ROI can be obtained by the following procedure.
May be determined. First, C for the entire scan area
Display the mode image. When the target valve is grasped and the stop position is set by a SW key or the like, a 3D-R of an appropriate size is obtained.
An OI guidewire appears to align with the C-mode plane. 3D
The ROI guidewire translates in the designated C-mode plane to determine the optimal position, and then determines the lateral spread. 3D so that a desired image can be obtained by the above means
-Determine the height of the ROI guidewire, determine the 3D-ROI and get a 3D representation.

The C-mode image is a simple 3D-ROI
3D-ROI not only works as a setting guide
3D transmission display (either MIP or integral value display) is displayed at the same time, and the entire valve movement is observed in the 3D display.
At the same time, it can be used to observe the movement of a valve in a specific plane in a C-mode image.

The C-mode image may display not only B / W display but also color display. By using the C-mode color image determined in this way, it is possible to directly shift to applications such as blood flow measurement.

The present invention is not limited to the above-described embodiment, but can be variously modified and implemented.

[0064]

According to the present invention, the spatial resolution and the temporal resolution of the three-dimensional display inside the subject can be improved.

[Brief description of the drawings]

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

FIG. 2 is a diagram illustrating an example of a three-dimensional scanable area.

FIG. 3 is a view showing a basic three-dimensional display example of the embodiment.

FIG. 4 is a view showing an example of a three-dimensional display according to the present embodiment involving automatic rotation of a tomographic plane.

FIG. 5 is a view showing an example of a three-dimensional display according to the present embodiment involving automatic movement of a tomographic plane.

FIG. 6 is a view showing a display example of a first scanning mode according to the embodiment.

FIG. 7 is a view showing a display example of a second scanning mode according to the embodiment.

FIG. 8 is a view showing a display example of a third scanning mode according to the embodiment.

FIG. 9 is a view showing another display example of the third scanning mode according to the embodiment.

FIG. 10 is a diagram showing an example of a time-division scanning sequence in a third mode of the embodiment.

FIG. 11 is an explanatory diagram of a method for setting a local region of interest in three-dimensional scanning in FIGS. 8 and 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Two-dimensional array type ultrasonic probe, 2 ... Transmission / reception unit, 3 ... Beam former unit, 4 ... Echo processor, 5 ... Doppler processor, 6 ... Application processor, 7 ... Monitor, 8 ... 3D processor, 9 ... Display unit, 10: Host CPU, 11: Operation panel, 12: Device body, 13: Image processing unit, 21: Transmitter, 22: Preamplifier, 23: Transmission / reception switch, 31: Beamformer

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yoichi Ogasawara 1385-1 Shimoishigami, Otawara City, Tochigi Prefecture F-term in the Toshiba Nasu Plant (reference) 2F068 AA40 CC07 DD04 DD07 FF12 FF16 GG01 JJ02 JJ04 JJ07 KK13 LL04 4C301 BB13 CC06 DD01 DD04 EE01 GB09 HH24 HH33 HH37 HH38 JB29 JB36 JB42 JC14 KK02 KK07 KK13 KK17 KK22 KK27 KK30 5B057 AA07 BA05 CD02 CD03 CE08

Claims (20)

[Claims] 1. A three-dimensional ultrasonic diagnostic apparatus capable of three-dimensionally scanning a three-dimensional region in a subject with an ultrasonic wave, wherein two arbitrary tomographic planes in the three-dimensional scanable region are two-dimensionally scanned with an ultrasonic wave. Then, two images corresponding to the two tomographic planes are generated, and the two images are position-aligned in accordance with the positional relationship between the two tomographic planes and combined and displayed.
Dimensional ultrasonic diagnostic equipment. 2. A three-dimensional ultrasonic diagnostic apparatus capable of scanning a three-dimensional region in an object with an ultrasonic wave, wherein two-dimensional scanning of an arbitrary tomographic plane in the three-dimensional region with an ultrasonic wave is performed on the tomographic surface. A first display mode in which a corresponding image is generated and displayed, and an arbitrary local region in the three-dimensional region is three-dimensionally scanned with ultrasonic waves to generate a three-dimensional image corresponding to the local region. A third display mode in which an image corresponding to the tomographic plane and the three-dimensional image are simultaneously displayed by combining a second display mode to be displayed with the first and second display modes.
A three-dimensional ultrasonic diagnostic apparatus, wherein the display mode can be selected. 3. The three-dimensionally scannable area is displayed three-dimensionally as a schematic figure, and the two images are aligned with the schematic figure according to the position of each tomographic plane and synthesized. The three-dimensional ultrasonic diagnostic apparatus according to claim 1, wherein the display is displayed. 4. In each of the first and third scanning modes, the three-dimensionally operable three-dimensional area is three-dimensionally displayed as a schematic figure, and the two-dimensional area is displayed on the schematic figure. 3. The three-dimensional ultrasonic diagnostic apparatus according to claim 2, wherein said images are aligned and synthesized according to the position of each tomographic plane. 5. The three-dimensional ultrasonic diagnosis according to claim 2, wherein in the third scanning mode, a scanning ratio between the first scanning mode and the second scanning mode can be changed. apparatus. 6. The three-dimensional ultrasonic diagnostic apparatus according to claim 1, wherein a graphic for supporting setting of the two tomographic planes in the three-dimensional scanable area is displayed. 7. In the second and third scan modes, a schematic figure representing the local area and the three-dimensional image are displayed in a position corresponding to each other. The three-dimensional ultrasonic diagnostic apparatus according to claim 1. 8. In the second and third scanning modes, a schematic figure representing the local area is displayed, and a three-dimensional image corresponding to the local area is displayed outside the schematic figure. 3. The three-dimensional ultrasonic diagnostic apparatus according to claim 2, wherein: 9. The method according to claim 1, wherein the two tomographic planes actually scanned by the ultrasonic waves are set so as to intersect at a center axis of the three-dimensional scannable area.
Dimensional ultrasonic diagnostic equipment. 10. A schematic diagram representing the three-dimensional scannable area and a schematic diagram representing an ultrasonic probe are displayed three-dimensionally with their directions aligned.
Or the three-dimensional ultrasonic diagnostic apparatus according to 2. 11. In the third scanning mode, an image corresponding to the tomographic plane is an ultrasonic image based on a signal derived from a tissue, and the three-dimensional image is a signal derived from a tissue or a signal derived from a blood flow. The three-dimensional ultrasonic diagnostic apparatus according to claim 2, wherein the three-dimensional ultrasonic diagnostic apparatus is an ultrasonic image based on: 12. In the third scanning mode, display transparency of an image corresponding to the tomographic plane and display transparency of the three-dimensional image can be individually set. The three-dimensional ultrasonic diagnostic apparatus according to claim 2. 13. The three-dimensional ultrasonic diagnostic apparatus according to claim 2, wherein support information for supporting a change in a size and a position of the local region is displayed. 14. The support information includes C information on a tomographic plane at an arbitrary depth substantially orthogonal to a central axis of the three-dimensional area.
The three-dimensional ultrasonic diagnostic apparatus according to claim 13, wherein a mode image is included. 15. The three-dimensional image according to claim 2, wherein an estimated position on the display of the three-dimensional image is changeable.
Dimensional ultrasonic diagnostic equipment. 16. The three-dimensional ultrasonic diagnostic apparatus according to claim 14, wherein the tomographic plane of the C-mode image is automatically moved up and down along the central axis of the three-dimensional region. 17. The three-dimensional ultrasonic diagnostic apparatus according to claim 1, wherein at least one of the two tomographic planes is automatically moved at arbitrary spatial and temporal intervals. 18. The three-dimensional ultrasonic diagnostic apparatus according to claim 17, wherein at least one of the two tomographic planes is automatically rotated about a center axis of the three-dimensional scanable area as a rotation center. 19. The three-dimensional ultrasonic diagnosis according to claim 17, wherein at least one of the two tomographic planes is automatically moved along a direction substantially orthogonal to at least one of the two tomographic planes. apparatus. 20. A three-dimensional ultrasonic diagnostic apparatus capable of three-dimensionally scanning a three-dimensional region in an object with an ultrasonic wave, wherein an arbitrary tomographic plane in the three-dimensionally scannable region is scanned with an ultrasonic wave, and the scanning is performed. Means for generating an ultrasonic image in the subject based on the information; means for generating a graphic image representing the three-dimensional scannable area; and Means for synthesizing and displaying an ultrasonic image.