JP5361166B2 - Ultrasonic diagnostic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic diagnostic apparatus preventing a change in luminance of an ultrasonic tomographic image even if preventing artifact. <P>SOLUTION: This ultrasonic diagnostic apparatus includes detection means for detecting ultrasonic beam having an emission angle of the vibrators of an ultrasonic probe 001 relative to a normal of a plane in the arrangement direction of the vibrators exceeds a predetermined allowable angle, a transceiver section 002 for transmitting and receiving the ultrasonic beams via the ultrasonic probe 001, gain adjustment means reducing the amplitude of the ultrasonic beam having the emission angle to the normal exceeding the allowable angle, a signal processing section 004 subjecting data to signal processing based on the gain-adjusted ultrasonic echo and generating raster data, an image processing section 005 changing the generated raster data into an orthogonal coordinate system to generate an ultrasonic tomographic image, and a display control section 007 controlling display means to display the generated ultrasonic tomographic image. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to an ultrasonic diagnostic apparatus having a two-dimensional multi-probe, and more particularly to an ultrasonic diagnostic apparatus that performs scanning along a scanning plane to which tilt or rotation is applied.

  Conventionally, a plurality of ultrasonic transducers are arranged in a matrix on an ultrasonic probe (hereinafter, a plane on which the ultrasonic transducers are arranged is referred to as an “element plane”). 2. Description of the Related Art An ultrasound diagnostic apparatus having a multi-plane mode that generates two different two-dimensional plane ultrasonic tomographic images in a three-dimensional region of a specimen is used (see, for example, Patent Documents 1 to 3). In the multi-plane mode, one of the two image planes has a fixed orientation relative to the element plane. An image plane in which this orientation is fixed is called a “reference plane”. As the reference plane, a plane that is orthogonal to the element plane of the ultrasonic transducer of the two-dimensional probe and that intersects the center of the element plane is usually selected. The other image plane is tilted with respect to the reference plane (tilt with respect to the element plane) and rotated after tilting (with a straight line corresponding to a normal line from the center of the element plane in the tilted plane as an axis). Rotation). Such an image plane is called an “intersection plane”.

  Here, the tilt and rotation will be described in detail with reference to FIG. FIG. 2 is a diagram for explaining the scanning plane of the ultrasonic beam in the multi-plane mode. The element plane 201 is a plane in which the transducers in the two-dimensional array probe are arranged in a matrix. An ultrasonic beam is emitted at an angle with respect to the center 206 of the element plane 201. A normal line 204 is a normal line passing through the center of the element plane. The reference plane 202 is a plane orthogonal to the element plane 201 and passing through the center 206, that is, including the normal line 204. Furthermore, a plane that is different from the reference plane 202 and is obtained by tilting a plane 208 including the normal line 204 by an angle θ is the intersecting plane 203. A straight line 205 corresponding to the normal line 204 of the element plane 201 in the intersecting plane 203 is a straight line 205. Then, rotating the tilted crossing surface 203 means rotating about the straight line 205 as a rotation axis.

  The ultrasonic diagnostic apparatus receives echo signals corresponding to the scanning lines of the ultrasonic beams in the reference plane and the intersecting plane, performs predetermined signal processing on the received echo signals, and displays an image in the signal processing result. Processing is performed to obtain image data of ultrasonic tomograms in each plane.

  Here, a grating lobe is one of the factors that hinder high-precision diagnosis in the ultrasonic diagnostic apparatus. A grating lobe is a phenomenon similar to the intensity distribution of light generated by a diffraction grating, and is a phenomenon in which an ultrasonic beam is generated in a different direction from the ultrasonic beam emitted from each ultrasonic transducer. Thus, an artifact (virtual image) is generated on the drawn ultrasonic tomographic image.

  This artifact (virtual image) tends to occur when the angle of the scanning line of the ultrasonic beam from the normal of the element plane of the two-dimensional probe is large due to the nature of the grating lobe. Therefore, conventionally, in an ultrasonic diagnostic apparatus, the scan angle of an ultrasonic beam is limited to be within an allowable angle range in order to prevent occurrence of artifacts due to grating lobes.

This allowable angle will be described with reference to FIG. Reference plane 202 is a plane including the normal line 204, the angle theta ₀ from the normal 204 to advance artifacts injection was not as ultrasound beam generated in a plane containing such normal 204 is set as the allowable angle ing. That is, an artifact occurs in the ultrasonic beam whose angle from the normal line 204 exceeds the allowable angle θ ₀ . In other words, if an ultrasonic beam is contained in a cone having a vertex 206 as the center and a center axis as the normal 204 and a bottom surface as the circle 207, the generation of artifacts can be suppressed. An artifact is generated in the sound beam. For example, the allowable angle θ ₀ is generally set to 45 degrees.

JP 2005-537075 A JP 2005-537079 A JP 2005-537076 A

  However, in the ultrasonic diagnostic apparatus having the multi-plane mode, when the tilt amount of the intersection plane increases, the angle of the scanning line of the ultrasonic beam from the normal line of the element plane increases. Here, the tilt amount is the magnitude of the inclination of the intersecting plane with respect to a plane orthogonal to the element plane including the normal line of the element plane. Furthermore, when the rotation is applied after the tilt is applied, the angle of the scanning line of the ultrasonic beam from the normal of the element plane is further increased. For this reason, since a grating lobe is likely to occur on an intersecting surface to which tilt or rotation is applied, it is necessary to change the allowable angle in accordance with the tilt or rotation.

Here, generation of artifacts in the multiplane mode will be described with reference to FIG. As described above, since the allowable angle range is determined based on the plane including the normal line 204, when the rotation is performed after the tilt or the tilt is applied, the cone 206 is the top and the circle 207 is the bottom. It will stick out. For example, the crossing surface 203 should emit an ultrasonic beam from the straight line 205 to an angle θ, and in this case, the ultrasonic beam emitted to the region 209 and the region 210 protrudes from the cone. Become. Therefore, artifacts are generated by the ultrasonic beam in this portion. Although the phenomenon that the ultrasonic beam protrudes from the cone also occurs due to tilt, a larger range protrudes when rotation is applied to the tilted plane. The ultrasonic beam protruding from the cone is an ultrasonic beam having an angle larger than θ ₀ from the normal line 204.

Here, in order to prevent artifacts due to grating lobes, in order not to scan an ultrasonic beam whose angle from the normal line 204 is larger than the allowable angle θ ₀ by tilting or rotating, the ultrasonic wave in the intersecting plane is not scanned. It is necessary to reduce the number of scanning lines of the beam. However, when the number of scanning lines is reduced, the frame rate (Hz), which is the number of ultrasonic tomographic images generated per time, changes. Here, there is a limitation on the transmission power of the ultrasonic wave that can be incident on the subject for reasons such as heat generation of the vibrator. The transmission power of this ultrasonic wave depends on the repetition period of the ultrasonic beam, that is, the frame rate. Specifically, if the transmission power of the ultrasonic beam per unit area when the frame rate is 20 Hz is determined, the same number of ultrasonic beams are emitted to the subject when the frame rate is higher than 20 Hz. In order to achieve this, it is necessary to reduce the transmission power of the ultrasonic wave, and when the frame rate is lower than 20 Hz, the transmission power of the ultrasonic wave is increased to obtain a clearer image. As described above, when the frame rate changes, the temporal resolution of the ultrasonic tomographic image changes, and the transmission power of the ultrasonic beam changes to change the luminance of the image. Therefore, in the conventional ultrasonic diagnostic apparatus, when the tilt amount of the intersection plane is changed, if the artifact due to the grating lobe is to be prevented, the tilt amount and the rotation amount of the intersection plane change, and the way the ultrasonic tomogram is viewed. As a result, it was difficult to make an accurate diagnosis.

  The present invention has been made in view of such circumstances, and an object thereof is to provide an ultrasonic diagnostic apparatus in which the luminance of an ultrasonic tomographic image does not change even when artifacts are prevented.

In order to achieve the above object, the ultrasonic diagnostic apparatus according to claim 1 receives ultrasonic wave position information and receives ultrasonic waves from a plurality of two-dimensionally arranged transducers of an ultrasonic probe. Detecting means for detecting an ultrasonic beam having an emission angle with respect to a normal line of a plane in the arrangement direction of the plurality of transducers exceeding a predetermined allowable angle; and the ultrasonic beam via the ultrasonic probe. Transmission / reception means for transmitting to the subject and receiving ultrasonic echoes reflected by the subject, a signal processing unit for performing signal processing on the data based on the ultrasonic echoes to create raster data, and orthogonally creating the created raster data Image processing means for generating an ultrasonic tomographic image by changing to a coordinate system, and pixels corresponding to the ultrasonic beam having an emission angle with respect to a normal line exceeding the allowable angle in the generated ultrasonic tomographic image Comprising a masking means for applying a mask, and a display control means for displaying on the display unit an ultrasonic tomographic image the mask has been applied, the scanning plane is the plane in which the plurality of transducers are arranged orthogonally In addition, a reference scanning plane that intersects the center of the plane, and a rotation with respect to the reference scanning plane with respect to the plane and a straight line that corresponds to a normal line from the center of the plane in the inclined plane is possible. The number of scanning lines on the reference scanning surface and the number of scanning lines on the intersecting scanning surface are the same .

According to the ultrasonic diagnostic apparatus of claim 1 , a mask is applied to a pixel corresponding to a scanning line by an ultrasonic beam whose angle from a normal passing through the center of the element plane exceeds an allowable angle (decreasing luminance, etc.) Thus, display of an image created by the ultrasonic beam can be suppressed. Thereby, the display of the image produced | generated by the ultrasonic echo inject | emitted in the direction in which the artifact by a grating lobe is easy to generate | occur | produce can be suppressed. Furthermore, since the number of emitted ultrasonic beams does not change, the luminance for each ultrasonic tomographic image can be set to the same luminance without changing the frame rate. Therefore, it is possible to generate a highly accurate and easy-to-see ultrasonic tomographic image in which disturbance due to artifacts is suppressed by the mask.

[First Embodiment]
Hereinafter, an ultrasonic diagnostic apparatus according to a first embodiment of the present invention will be described. FIG. 1 is a block diagram showing functions of an ultrasonic diagnostic apparatus according to the present invention.

  The ultrasonic probe 001 includes a plurality of piezoelectric vibrators such as piezoelectric ceramics arranged in a matrix in a plane. The piezoelectric vibrator receives a voltage pulse input from the transmission / reception unit 002 and vibrates by the voltage to generate a directional ultrasonic beam. The piezoelectric element transmits the ultrasonic beam to the subject. The ultrasonic probe 001 receives an ultrasonic echo obtained by reflecting the transmitted ultrasonic beam at a discontinuous surface of the acoustic impedance of the subject with a piezoelectric vibrator. Then, the piezoelectric vibrator converts the received ultrasonic echo into an echo signal that is an electrical signal, and outputs the echo signal to the transmission / reception unit 002.

Next, the scanning plane by the ultrasonic probe 001 will be described with reference to FIG. 2 are two different two-dimensional planes in the three-dimensional region of the subject to be scanned by the operator. The plane on which the piezoelectric vibrators of the ultrasonic probe 001 are arranged is an element plane 201. In FIG. 2, the element plane 201 is shown as a plane parallel to the XY plane. An ultrasonic beam is emitted from the element plane 201 to the Z side. The ultrasonic beam emitted from the ultrasonic probe 001 scans the two scanning planes at a predetermined angle. Of these two planes, the scanning plane parallel to the XZ plane is the reference plane 202. The reference plane 202 is a plane that passes through the center 206 of the element plane 201 and includes a normal line 204 from the center 206. The ultrasonic beam emitted from the ultrasonic probe 001 scans within the range of the angle ± θ ₀ from the normal line 204 on the reference plane 202. This θ ₀ corresponds to the “allowable angle” in the present invention. Here, the allowable angle is predetermined for each probe, for example, θ ₀ = 45 °. The artifacts in the scanning line the angle from the normal line 204 is larger than theta ₀ occurs. That is, an artifact occurs in a scanning line having the center 206 as a vertex and not included in a cone having a circle 207. In addition, the ultrasonic probe 001 forms a plurality of scanning lines 301 (raster) in the reference plane 202 as shown in FIG. FIG. 3A is a diagram showing scanning lines of ultrasonic beams in the reference plane.

The other scanning plane is the intersection plane 203. This intersecting surface 203 is obtained by inclining an angle θ about a straight line passing through the center 206 of the element plane 201 and including the normal line 204 with the element plane 201. The angle θ is an angle formed between the normal line 204 and the straight line 205. A straight line in the intersecting plane 203 corresponding to the normal line 204 in the plane 208 is a straight line 205. The ultrasonic beam emitted from the ultrasonic probe 001 scans the range of the angle ± θ ₀ from the straight line 205 on the intersecting plane 203. The ultrasonic probe 001 forms a plurality of scanning lines 302 in the intersecting plane 203 as shown in FIG. FIG. 3B is a diagram showing scanning lines of ultrasonic beams in the intersection plane 203. Here, in the present embodiment, only the tilt is described. However, even when the rotation of the angle φ is applied about the straight line 205 after the tilt of the angle θ, the tilt and the rotation are similarly applied on the intersecting plane. The range of the angle ± θ ₀ from the straight line 205 is scanned. As shown in FIG. 2, when scanning within the range of the allowable angle ± θ ₀ on the intersecting plane 203, the regions 209 and 210 are protruding from a cone having a center 206 as a vertex and a circle 207. That is, artifacts occur in the scanning lines that scan the area 209 and the area 210.

FIG. 3B shows a scanning line 302 of the ultrasonic beam in the intersecting plane 203. As described above, the allowable angle between the reference plane 202 and the intersecting plane 203 is the same as ± θ ₀ , and the number and density of the scanning lines 301 shown in FIG. 3A are shown in FIG. 3B. The number and density of the scanning lines 302 are the same. Note that in FIGS. 3A and 3B, the number of the scanning lines 301 and the scanning lines 302 is reduced in order to avoid complication of the drawings, but actually, the reference plane 202 and the intersecting plane 203 are used. More scanning lines are formed, and the scanning line density becomes dense. Also, the dotted line area 209 and area 210 in FIG. 3 are areas protruding from a cone having a center 206 as a vertex and a circle 207 when scanning on the intersection plane 203 within the range of the allowable angle ± θ ₀ .

  Note that, from the ultrasonic probe 001, an ultrasonic beam along the reference plane 202 and an ultrasonic beam along the intersecting plane 203 are alternately emitted in a time division manner.

The system control unit 008 performs overall control of the transmission / reception unit 002, the signal processing unit 004, the image processing unit 005, and the display control unit 007. The system control unit 008 receives position information of the two scanning planes of the reference plane 202 and the intersecting plane 203 input by a doctor or a laboratory technician (hereinafter simply referred to as “operator”) via the user interface 009. . Here, the position information of the intersecting plane 203 includes the position information of the plane 208 that is the basis of the tilt and rotation of the intersecting plane including the normal of the element plane, that is, the angle from the reference plane 202 and coordinates representing the plane. The angle of tilt from 208 (for example, the angle θ ° in FIG. 2) and the angle of rotation (for example, the rotation angle of the intersecting surface 203 with the straight line 205 in FIG. 2 as an axis. Here, φ is designated). Determined by Based on the angle from the straight line 205 of the scanning line in the specific intersection plane 203, the received tilt angle θ, and the rotation angle φ, the system control unit 008 uses the rotation matrix of each angle to generate the line from the normal line 204. An angle α to the scanning line is obtained. Then, the system controller obtains whether this angle α is greater than an allowable angle theta _0. The system control unit 008 outputs to the transmission / reception unit 002 whether or not the angle α from the normal line 204 in the emission direction of the specific scanning line exceeds θ ₀ . This system control unit 008 includes the “detection means” in the present invention.

  The transmission / reception unit 002 is provided with a transmission pulse generator, a transmission delay circuit, a pulser, a reception delay circuit, an adder (all not shown), and a gain adjustment unit 003 (preamplifier). The transmission / reception unit 002 corresponds to “transmission / reception means” in the present invention.

  The transmission pulse generator generates a transmission pulse signal for forming an ultrasonic beam for each rate pulse (ultrasonic wave transmission / reception reference rate) based on a constant pulse repetition frequency (PRF: Pulse Repetition Frequency). The transmission pulse generator generates a transmission pulse signal for forming a desired ultrasonic beam. The transmission pulse signal is a control pulse signal for emitting an ultrasonic pulse. This transmission pulse signal is distributed by the number of transmission channels and sent to the transmission delay circuit. In the transmission delay circuit, timing control data for determining the delay time is input from the system control unit 008 for each transmission channel. Based on this timing control data, the transmission delay circuit delays the transmission pulse signal for each transmission channel. The delayed transmission pulse signal is input to the pulsar for each transmission channel. The pulser applies a voltage pulse to each piezoelectric vibrator (transmission channel) at the timing of receiving the transmission pulse signal. Thereby, an ultrasonic beam is emitted from the ultrasonic probe 001. The emission direction of the ultrasonic beam is determined by an input from the system control unit 008, and thereby the direction of the scanning line is determined.

The gain adjusting unit 003 is a preamplifier, and amplifies echo signals received by the piezoelectric elements (reception channels) of the ultrasonic probe 001. The gain adjustment unit 003 receives from the system control unit 008 whether or not the angle α from the normal line 204 in the scanning line emission direction exceeds the allowable angle θ ₀ at the timing of receiving the ultrasonic transmission / reception reference rate. That is, it can be determined whether or not the corresponding scanning line exceeds the allowable angle θ ₀ at the timing of the ultrasonic transmission / reception reference rate. At this time, the gain adjustment unit 003 receives the echo corresponding to the scan line based on the information input from the system control unit 008 that the angle α from the normal line 204 in the emission direction of the scan line exceeds the allowable angle θ _0. The brightness of the echo signal is lowered by decreasing the signal gain adjustment set value (for example, by reducing the value to be multiplied). Thereby, when the image is generated, the image corresponding to the scanning line on the image is not visible to the operator. This gain adjusting unit 003 corresponds to “gain adjusting means” in the present invention.

  Here, in this embodiment, the gain adjustment unit 003 is arranged in the transmission / reception unit 002. However, this may be arranged in the signal processing unit 004, and is arranged separately from the transmission / reception unit 002 and the signal processing unit 004. May be.

  The adder phasing-adds the signals of the respective reception channels delayed by the reception delay circuit to generate a single signal.

  The signal processing unit 004 includes a low-pass filter, an envelope detection circuit, and a logarithmic compression unit (all not shown), and executes signal processing for generating a two-dimensional image. The low-pass filter removes high-frequency components of the signal received from the transmission / reception unit 002. The envelope detection circuit detects an envelope and obtains an envelope detection signal. The logarithmic compression unit performs logarithmic conversion on the envelope detection signal. By performing the processing as described above, the signal processing unit creates raster data from data based on ultrasonic echoes. The created raster data is transmitted to the image processing unit 005. This signal processing unit 004 corresponds to “signal processing means” in the present invention.

  The image processing unit 005 includes a scan converter (SC) 006, and converts the data input from the signal processing unit 004 into image data of an orthogonal coordinate system. This image processing unit 005 corresponds to the “image processing means” in the present invention.

  The display control unit 007 displays the image data generated by the image processing unit 005 on a display unit (not shown). That is, the display control unit 007 displays the reference plane 202 and the intersecting plane 203 schematically shown in FIGS. 3A and 3B on the screen of the display unit. This display control unit 007 corresponds to “display control means” in the present invention.

  The user interface 009 is an input user interface for inputting an operator's operation. Information about the operation content input via the user interface 009 is sent to the system control unit 008.

  Next, the operation of ultrasonic tomographic image display in the ultrasonic diagnostic apparatus according to the present embodiment will be described with reference to FIG. Here, FIG. 4 is a flowchart of ultrasonic tomographic image display in the ultrasonic diagnostic apparatus according to the present embodiment.

  Step S001: The operator uses the user interface 009 to input crossing plane information (a plane on which tilt and rotation are based, a tilt angle, and a rotation angle).

  Step S002: The system control unit 008 obtains an angle from the normal of the element plane of each scanning line that scans the intersection plane based on the intersection plane information input from the user interface 009, and the angle and the allowable angle. To obtain a scanning line exceeding the allowable angle. Further, the system control unit 008 outputs information on the scanning line exceeding the allowable angle to the gain adjustment unit 003 of the transmission / reception unit 002.

  Step S003: The transmission / reception unit 002 transmits an ultrasonic beam toward the subject via the ultrasonic probe 001, and further receives an ultrasonic echo reflected by the subject.

Step S004: Based on the information received from the system control unit 008, the gain adjustment unit 003 determines whether the angle α from the normal line 204 of the corresponding scanning line exceeds the allowable angle θ ₀ for each received ultrasonic echo. Judge whether or not. When the angle α exceeds the allowable angle θ ₀ , the process proceeds to step S005, and when the angle α does not exceed the allowable angle θ ₀ , the process proceeds to step S006.

  Step S005: The gain adjustment unit 003 decreases the amplitude of the signal data obtained by the ultrasonic beam corresponding to the scanning line exceeding the allowable angle. The transmission / reception unit 002 outputs the signal data subjected to gain adjustment to the signal processing unit 004.

  Step S006: The signal processing unit 004 performs signal processing such as envelope detection on the signal data input from the transmission / reception unit 002 to generate raster data. The signal processing unit 004 performs signal processing and outputs raster data to the image processing unit 005.

  Step S007: The image processing unit 005 performs coordinate conversion to the orthogonal coordinate system on the raster data input from the signal processing unit 004, and generates an ultrasonic tomographic image. The image processing unit 005 outputs the generated ultrasonic tomographic image to the display control unit 007.

  Step S008: The display control unit 007 causes the display means to display the ultrasonic tomographic image input from the image processing unit 005.

  By repeating the above-described operation, each time the tilt angle or rotation angle of the intersection plane is changed, the ultrasonic diagnostic apparatus according to the present embodiment obtains a scanning line that exceeds the allowable angle, and signal data corresponding to the scanning line. And the image corresponding to the scanning line is not displayed on the screen of the display unit.

  As described above, the ultrasonic diagnostic apparatus according to the present embodiment can reduce the amplitude of the signal data based on the ultrasonic echo corresponding to the scanning line exceeding the allowable angle. Thereby, it is possible to suppress the occurrence of artifacts due to scanning lines exceeding the allowable angle without changing the number of emitted ultrasonic beams, that is, without changing the frame rate. For this reason, the operator can make a diagnosis by referring to an image in which the occurrence of artifacts is suppressed and all the images have the same luminance, and the ultrasonic diagnostic apparatus according to the present embodiment can perform accurate ultrasonic diagnosis. Can contribute.

[Second Embodiment]
An ultrasonic diagnostic apparatus according to the second embodiment of the present invention will be described. The configuration of the ultrasonic diagnostic apparatus according to this embodiment is the same as that of the ultrasonic diagnostic apparatus according to the first embodiment shown in FIG. 1, and the operations of the gain adjustment unit 003 and the image processing unit 005 are different. .

  In the first embodiment described above, the gain of the signal data of the transmission / reception unit 002 is adjusted. However, in the present embodiment, artifact display is suppressed by performing mask processing on the generated ultrasonic tomographic image.

Based on the timing at which the ultrasonic transmission / reception reference rate is transmitted, the system control unit 008 determines that the angle α from the normal line 204 through which the scanning line corresponding to the ultrasonic transmission / reception reference rate passes through the center 206 of the element plane 201 is the allowable angle θ _0. Is output to the transmission / reception unit 002.

Based on the timing of receiving the ultrasonic transmission / reception reference rate, the transmission / reception unit 002 adds information indicating whether or not the allowable angle θ ₀ is exceeded with respect to the scanning line corresponding to the ultrasonic transmission / reception reference rate to the signal processing unit 004. Output.

  The gain adjustment unit 003 performs the same gain adjustment on all the signal data based on the ultrasonic echo received by the transmission / reception unit 002.

The SC 006 included in the image processing unit 005 refers to the information on whether or not the scanning line added to the scanning line exceeds the allowable angle θ ₀ at the center 206 of the element plane 201 received from the system control unit 008. Mask processing is performed on pixels corresponding to scanning lines in which the angle α from the normal line 204 exceeds the allowable angle θ ₀ . The mask here is, for example, to darken the luminance of the corresponding pixel. This is because the image processing unit 005 originally stores the position of the pixel corresponding to each scanning line, and if the scanning line is specified, the pixel corresponding to the scanning line can be obtained. As a result, an image corresponding to the scanning line is not displayed. This SC006 includes the “mask means” in the present invention.

  As described above, in the ultrasonic diagnostic apparatus according to this embodiment, it is possible to suppress the generated ultrasonic tomographic image from being masked and displayed as an image. Thereby, it is possible to suppress the occurrence of artifacts due to scanning lines exceeding the allowable angle without changing the number of emitted ultrasonic beams, that is, without changing the frame rate. For this reason, the operator can make a diagnosis by referring to an image in which the occurrence of artifacts is suppressed and all the images have the same luminance, and the ultrasonic diagnostic apparatus according to the present embodiment can perform accurate ultrasonic diagnosis. Can contribute.

Block diagram of an ultrasonic diagnostic apparatus according to the present invention Diagram for explaining the operation surface of the ultrasonic beam in multiplane mode (A) The figure which shows the scanning line of the ultrasonic beam in a reference plane, (B) The figure which shows the scanning line of the ultrasonic beam in an intersection surface The figure of the flowchart of the image generation of the ultrasonic diagnosing device concerning a 1st embodiment.

Explanation of symbols

001 Ultrasonic probe 002 Transmission / reception unit 003 Gain adjustment unit 004 Signal processing unit 005 Image processing unit 006 SC (scan converter)
007 Display control unit 008 System control unit 009 User interface

Claims (1)

In response to the input of the position information of the scanning surface, the emission angle of the ultrasonic beam from the two-dimensionally arranged transducers of the ultrasonic probe with respect to the normal line of the plane in the arrangement direction of the plurality of transducers is set in advance. Detecting means for detecting an ultrasonic beam exceeding a predetermined allowable angle;
Transmission / reception means for transmitting the ultrasonic beam to the subject and receiving an ultrasonic echo reflected by the subject via the ultrasonic probe;
A signal processing unit that performs raster signal processing on data based on the ultrasonic echo to create raster data;
Image processing means for generating an ultrasonic tomographic image by changing the created raster data to an orthogonal coordinate system;
Mask means for masking pixels corresponding to the ultrasonic beam having an emission angle with respect to a normal line exceeding the allowable angle in the generated ultrasonic tomographic image;
Display control means for displaying on the display means an ultrasonic tomographic image subjected to the mask ,
The scanning plane is
A reference scanning plane orthogonal to the plane on which the plurality of transducers are arranged and intersecting the center of the plane;
A cross-scanning surface that allows rotation with respect to the reference scanning surface and a straight line corresponding to a normal line from the center of the plane in the inclined plane and the inclined plane;
Consists of
The ultrasonic diagnostic apparatus , wherein the number of scanning lines on the reference scanning plane and the number of scanning lines on the intersecting scanning plane are the same .

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