JP2006314518A - Ultrasonic diagnostic unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic diagnostic unit by which operations of designating the section for distance measuring can be easily and quickly performed. <P>SOLUTION: The unit is provided with a display unit 7 which displays a three-dimensional image G of an examinee, a cross-section changing operation part 81 which designates the position of cross-section of the displayed three-dimensional image G, a cross-sectional image generation part 110 which generates a three-dimensional cross-sectional image G' of the cross-section in the designated position of cross-section, a measurement point input operation part 82 which inputs measurement points on the cross-section of the displayed three-dimensional cross-sectional image G' and a distance calculation part 124 which calculates the distance between the two measurement positions of the examinee which are specified by the inputted two measurement points. It is also provided with a straight line calculation part 121 which determines the straight line connecting the inputted two measurement points and an intersecting point calculation part 123 which determines the intersecting point between the cross-section of the three-dimensional cross-sectional image G' and the straight line. The display unit 7 displays a marker M indicating the position of the intersecting point on the cross-section. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an ultrasonic diagnostic apparatus that transmits an ultrasonic wave to a subject and forms a medical image based on the echo signal, and more particularly, an arbitrary section within the subject such as the length and thickness of a region of interest and its peripheral region. The present invention relates to an ultrasonic diagnostic apparatus having a function of measuring the distance.

  Conventionally, an ultrasonic diagnostic apparatus having a function of measuring the length and thickness of a region of interest of a subject has been widely used (see, for example, Patent Document 1). Such an ultrasonic diagnostic apparatus receives a designation of a measurement start point and end point on a two-dimensional ultrasonic image, and calculates an actual distance corresponding to a section connecting the start point and end point. It is equipped with.

  By the way, in recent years, techniques related to three-dimensional display of ultrasonic images have attracted attention and are expected to spread. In the three-dimensional display of the ultrasonic image, data is collected by performing a three-dimensional scan on the region of interest, and a three-dimensional image is reconstructed from a plurality of tomographic images based on the collected data. This is implemented by projecting and displaying (rendering) on a three-dimensional screen. As the rendering process, techniques such as MPR (Multi-Planar Reconstruction / Reformation) method, MIP (Maximum Intensity Projection) method, VR (Volume Rendering) method and the like are used.

  Patent Document 2 discloses a configuration for displaying a three-dimensional image using the MPR method. The ultrasonic diagnostic apparatus of the same document has a function of displaying a diagram (referred to as “three-side view”) representing three different sections of a three-dimensional image such as a region of interest.

  FIG. 14 shows an example of a display form of a three-view drawing. On the display screen V, a three-dimensional image G of the region of interest R and its peripheral region S and three cross-sectional images G1 to G3 different from this three-dimensional image G are displayed simultaneously. The cross-sectional images G1 to G3 correspond to three cross sections orthogonal to each other of the three-dimensional image G.

  In a conventional ultrasonic diagnostic apparatus capable of displaying a three-dimensional image, the length and thickness of a region of interest are measured using a two-dimensional image, that is, a three-view drawing, as in Patent Document 1. More specifically, first, a cross-section suitable for distance measurement is found while changing the cross-sectional direction of the three-dimensional image, and a three-view diagram including the cross-sectional image is displayed. A cross section suitable for distance measurement in FIG. Next, a section for measuring the distance is designated on the cross-sectional image G2. The section is designated by designating measurement points a, b, c, and d on the cross-sectional image G2. Here, the measurement points a and d are specified on the peripheral region S, and the measurement points b and c are specified on the region of interest R. The ultrasonic diagnostic apparatus has an actual distance corresponding to a section obtained by connecting two of the measurement points a to d with a straight line, that is, the position (measurement position) of the subject specified by the two measurement points. The distance between is calculated. In the case of FIG. 14, the distance from the peripheral site S corresponding to the sections ab and cd to the outer periphery of the site of interest R and the passing length of the site of interest R corresponding to the distance of the section bc are calculated.

JP-A-6-125893 JP 2003-265475 A (Company) Japan Medical Imaging System Association “Medical Image / Radiological Equipment Handbook”, Meiko Art Printing Co., Ltd., September 28, 2001, p. 225-228

  The following problems have been pointed out in distance measurement using such a conventional ultrasonic diagnostic apparatus. First, there is a problem in that it is troublesome to display three views of various cross sections in order to find a cross section suitable for distance measurement. Furthermore, if the cross section that seems to be appropriate is not actually satisfied, it is necessary to display three views of various cross sections again in order to find the appropriate cross section again. At the same time, the measurement time was prolonged.

  In addition, it is considered that distance measurement can be performed while observing a three-dimensional image, but this is not possible with a conventional ultrasonic diagnostic apparatus. That is, the operator observes the three-dimensional image, determines a distance measurement section, designates the determined section on the image, and measures the distance. Therefore, if a section can be specified on a three-dimensional image, distance measurement can be performed with good operability, and the measurement time can be shortened. However, in the conventional configuration, since the section designation operation cannot be performed unless the display screen is switched from the three-dimensional image to the three-view drawing, it is difficult to say that both operability and measurement time are good.

  Moreover, each cross-sectional image which comprises a three-view figure is displayed on the small area | region which divided the display screen into 4 (refer FIG. 14). Therefore, it has been difficult to find an appropriate cross-section while changing the cross-sectional direction of such a small cross-sectional image. In addition, there are a method of enlarging the cross-sectional image and a method of displaying only the cross-section to be measured. The work could not be omitted, and in the end, it took a lot of time and effort to specify the measurement section.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide an ultrasonic diagnostic apparatus capable of simply and quickly performing an operation for specifying a section in which distance measurement is performed.

  In order to achieve the above object, the invention described in claim 1 generates voxel data based on a received signal obtained by scanning a subject with ultrasonic waves, and generates a three-dimensional image based on the voxel data. Image generating means for displaying, display means for displaying the generated three-dimensional image, first operating means for designating a cutting position of the displayed three-dimensional image, and the designated cutting position. Cutting image generating means for generating a three-dimensional cut image composed of the cut three-dimensional image, and inputting measurement points on the cut surface of the generated three-dimensional cut image displayed on the display means And a distance calculating means for calculating a distance between two measurement positions of the subject specified by the two input measurement points. Diagnostic device .

  The invention according to claim 2 is the ultrasonic diagnostic apparatus according to claim 1, wherein the cut image generating means receives the operation from the first operating means and displays the displayed 3 A plurality of three-dimensional cut images having cut surfaces at different positions in the depth direction of the three-dimensional image are sequentially generated, and the display unit sequentially displays the plurality of the three-dimensional cut images generated in sequence. To do.

  The invention according to claim 3 is the ultrasonic diagnostic apparatus according to claim 1 or claim 2, wherein a straight line for obtaining a straight line connecting the two measurement points input by the second operating means. A calculation means; and an intersection calculation means for obtaining an intersection point between the cut surface of the three-dimensional cut image generated by the cut image generation means and the calculated straight line, and the display means includes the calculation A marker indicating the position of the intersection point is displayed on the cut surface.

  The invention according to claim 4 is the ultrasonic diagnostic apparatus according to claim 3, wherein the cut image generating means is orthogonal to the straight line obtained by the straight line calculating means, and the 2 A three-dimensional cut image having a cut surface including one of the two measurement points is generated, and the display means displays the generated three-dimensional cut image.

  Further, the invention according to claim 5 is the ultrasonic diagnostic apparatus according to claim 4, wherein the cut image generation means is different on the straight line in response to an operation from the first operation means. A plurality of three-dimensional cut images having a cut surface orthogonal to the straight line are sequentially generated at a position, and the display means sequentially displays the plurality of three-dimensional cut images generated sequentially. .

  The invention according to claim 6 is the ultrasonic diagnostic apparatus according to any one of claims 3 to 5, wherein the position is different from the marker on the cut surface of the three-dimensional cut image. When a new measurement point is inputted, an approximate straight line calculation means for obtaining an approximate straight line that approximates three or more measurement points including the two measurement points connected by the straight line and the new measurement point. The intersection calculation means obtains a new intersection where the cut surface of the three-dimensional cut image generated by the cut image generation means and the obtained approximate line intersect, and the display means A new marker indicating the obtained position of the new intersection is displayed on the cut surface.

  The invention according to claim 7 is the ultrasonic diagnostic apparatus according to claim 6, wherein the cut image generating means has a cut surface orthogonal to the approximate straight line, and the three or more A three-dimensional cut image having a cut surface including any one of the measurement points is generated, and the display means displays the generated three-dimensional cut image.

  The invention according to claim 8 is the ultrasonic diagnostic apparatus according to claim 7, wherein the cut image generation means receives an operation from the first operation means and is on the approximate straight line. A plurality of three-dimensional cut images having cut planes orthogonal to the approximate straight line are sequentially generated at different positions, and the display means sequentially displays the plurality of three-dimensional cut images generated in sequence. And

  The ultrasonic diagnostic apparatus according to the present invention is configured to display a three-dimensional cut image having a shape obtained by cutting a three-dimensional image of a subject at a cutting position designated by an operator. The operator designates a section in which distance measurement is performed by changing a cutting position of the three-dimensional cut image, that is, by inputting a measurement point while moving the cut surface. As a result, it is not necessary to display three views of various cross sections as in the prior art, and a section can be designated simply by displaying a three-dimensional cut image having a desired cut surface. Moreover, even if a cross-section that seems to be appropriate is actually unintentional, it is possible to find an appropriate cross-section only by changing the cut surface of the three-dimensional cut image. Therefore, according to the present invention, it is possible to easily and quickly perform an operation for specifying a section in which distance measurement is performed. In addition, since a section can be specified by inputting measurement points to the three-dimensional cut image itself, the operation can be simplified and speeded up.

  In addition, according to the ultrasonic diagnostic apparatus of the present invention, since it is possible to designate a section for distance measurement in a state where only a three-dimensional cut image is displayed on the display screen, the display screen is displayed when the size of the display screen is the same. The section designating operation can be performed using an image having a larger size as compared with the conventional three-view drawing in which a plurality of images are displayed divided into a plurality of images, and the operability can be improved and the operation can be speeded up.

  An example of a preferred embodiment of an ultrasonic diagnostic apparatus according to the present invention will be described in detail with reference to the drawings.

[Device configuration]
The block diagram shown in FIG. 1 represents an example of a schematic configuration of the ultrasonic diagnostic apparatus 1 according to the present embodiment. The ultrasonic diagnostic apparatus 1 includes an ultrasonic probe 2, a transmission / reception circuit 3, a signal processing circuit 4, a digital scan converter (DSC) 5, a volume rendering (VR) processing circuit 6, a display device 7, an operation unit 8, and a printing device 9. The data storage unit 10 and the control unit 100 are included.

  The ultrasonic probe 2 is a two-dimensional ultrasonic probe in which a plurality of piezoelectric elements that transmit and receive ultrasonic waves are arranged in a matrix (lattice), for example. By scanning the ultrasonic wave transmitted from the ultrasonic probe 2, three-dimensional data having a shape spreading radially from the transmission / reception surface of the ultrasonic probe 2 is received as an echo signal. A one-dimensional ultrasonic probe can be used as the ultrasonic probe 2. In that case, the ultrasonic probe 2 itself is mechanically scanned to collect three-dimensional data.

  The transmission / reception circuit 3 includes a transmission unit that supplies an electrical signal to the ultrasonic probe 2 to generate an ultrasonic signal, and a reception unit that receives an echo signal from the subject received by the ultrasonic probe 2.

  The transmission unit in the transmission / reception circuit 3 includes a clock generation circuit, a transmission delay circuit, a pulsar circuit, and the like (not shown). The clock generation circuit is a circuit that generates a clock signal that determines the transmission timing and transmission frequency of the ultrasonic signal. The transmission delay circuit is a circuit that focuses an ultrasonic signal to be transmitted by applying a delay to an electrical signal supplied to a predetermined piezoelectric element. The pulsar circuit includes a pulsar corresponding to the number of individual paths (channels) for each piezoelectric element of the ultrasonic probe 2, and generates an electric signal (driving pulse) at a timing corresponding to the delay by the transmission delay circuit. It is a circuit supplied to the element.

  The receiving unit of the transmission / reception circuit 3 includes a preamplifier circuit, an A / D conversion circuit, a reception delay / adder circuit, etc. (not shown). The preamplifier circuit is a circuit that amplifies an echo signal output from each piezoelectric element of the ultrasonic probe 2 for each reception channel. The A / D conversion circuit is a circuit that converts an amplified echo signal into a digital signal. The reception delay / adder circuit is a circuit that gives a delay time necessary for determining reception directivity to the A / D converted echo signal and performs addition processing. Thereby, the reflection component from the direction according to the reception directivity is emphasized.

  The signal processing circuit 4 includes processing circuits for each display mode, such as a B mode processing circuit, an M mode processing circuit, a Doppler processing circuit, and a color mode processing circuit. In addition to the above, the signal processing circuit 4 can be appropriately provided with a processing circuit corresponding to an arbitrary display mode. The echo signal output from the transmission / reception circuit 3 is subjected to the following processing by any processing circuit in the signal processing circuit 4.

  The B-mode processing circuit is a circuit that visualizes echo amplitude information, and performs processing for generating B-mode ultrasound raster data from the echo signal. More specifically, band-pass filter processing is performed on the echo signal, then the envelope of the output signal is detected, and the detected data is subjected to compression processing by logarithmic transformation. In addition, processing such as edge enhancement may be performed.

  The M-mode processing circuit is a circuit that visualizes the temporal position change of the echo, and obtains a motion curve representing the temporal change of the reflection source by modulating the luminance of the echo signal for each living body depth.

  The Doppler processing circuit includes a phase detection circuit, an FFT (Fast Fourier Transform) operation circuit, and the like, and extracts blood flow information in the subject by extracting the Doppler displacement frequency component from the echo signal and performing FFT processing or the like. Generate data that represents.

  The color mode processing circuit is a circuit that visualizes blood flow information in the subject, and performs processing for generating color ultrasound raster data from the echo signal. Blood flow information includes information such as blood flow velocity, dispersion, and power. This blood flow information is obtained as binarized information. More specifically, the color mode processing circuit includes a phase detection circuit, an MTI (Moving Target Indicator filter, an autocorrelator, a flow velocity / dispersion calculator, etc., and extracts a Doppler displacement frequency component from the echo signal. A tissue signal and a blood flow signal are separated by MTI filter processing (high-pass filter processing), and blood flow information such as blood flow velocity, dispersion, and power is obtained from the blood flow signal at multiple points by autocorrelation processing. In some cases, non-linear processing or the like for reducing the above is performed.

  The DSC 5 is a circuit that performs processing for converting the ultrasonic raster data from the signal processing circuit 4 into voxel data represented by orthogonal coordinates. The DSC 5 converts data represented by the scanning line signal sequence output from the signal processing circuit 4 into data in an orthogonal coordinate system (scan conversion processing). That is, in order to be able to display the signal train synchronized with the ultrasonic scanning on the television scanning system display device 7, the scanning system is converted by reading out in synchronization with the standard television scanning.

  The volume rendering (VR) processing circuit 6 performs volume rendering processing on the voxel data output from the DSC 5 to generate a three-dimensional image to be displayed on the display device 7. Volume rendering processing determines a predetermined line-of-sight direction (projection ray projection direction) for voxel data, performs ray-tracing processing from any line of sight, and integrates or weights voxel values (luminance values, etc.) on the line of sight This is a process of forming a three-dimensional image by extracting an organ or the like three-dimensionally by associating with an image pixel on the projection surface by cumulative addition or the like.

  Further, the VR processing circuit 6 performs a clipping process for removing a shielding object existing in front of the ROI when a region (region of interest; ROI) from which an ultrasound image is to be acquired is set by the operator. To extract data corresponding to the ROI and generate a three-dimensional image.

  The three-dimensional image generated by the VR processing circuit 6 is displayed by a display device 7 such as a CRT or LCD. The display device 7 corresponds to an example of the “display unit” of the present invention.

  The operation unit 8 includes various input devices such as a switch for starting / ending the apparatus, a keyboard, a mouse, a joystick, a trackball, and a TCS (Touch Command Screen). The operator operates the operation unit 8 to set the ROI, set the projection direction (gaze direction) of the projection light beam with respect to the voxel data, and further input the patient ID of the subject.

  The printing apparatus 9 includes a printer that prints image data and measurement data acquired by the ultrasonic diagnostic apparatus 1 on a recording sheet and outputs them. The printing apparatus 9 may be built in the ultrasonic diagnostic apparatus 1 or may be externally connected.

  The data storage unit 10 stores various data processed by the ultrasonic diagnostic apparatus 1 such as data generated by the signal processing circuit 4, DSC 5, VR processing circuit 6, and data processed by the control unit 100 or the like. To do. For example, these data are stored in the data storage unit 10 in a state of being organized as a searchable file (patient file) for each patient.

  As a storage device included in the data storage unit 10, a large-capacity storage device such as a DRAM or a hard disk drive can be used. Further, as the storage device, a drive device for writing and reading data on a recording medium such as a DVD-RAM, a CD-R, or an MO can be applied.

  The data storage unit 10 may be built in the ultrasonic diagnostic apparatus 1 or may be externally attached. Furthermore, a server (DICOM server) or a database connected to the ultrasonic diagnostic apparatus 1 via a network such as a LAN can be applied as the data storage unit 10.

  The control unit 100 includes a processor such as a CPU (central processing unit) that executes control of various units of the ultrasound diagnostic apparatus 1 and various arithmetic processes. The control unit 100 particularly controls processing circuits such as the transmission / reception circuit 3, the signal processing circuit 4, the DSC 5, and the VR processing circuit 6, controls display processing of various screens and images by the display device 7, and controls the printing device 9. Control of print processing, data storage processing for the data storage unit 10, data reading processing from the data storage unit 10, and the like are executed. The control unit 100 executes various processes in accordance with a program stored in advance in a nonvolatile storage device (not shown) such as a ROM or a hard disk drive. The configuration of the control unit 100 will be described in detail in [Control system configuration] below.

[Control system configuration]
Next, the configuration of the control system of the ultrasonic diagnostic apparatus 1 of the present embodiment will be described with reference to the block diagram shown in FIG. FIG. 2 mainly shows components that contribute to the realization of the operational effects of the present invention in the overall configuration of the ultrasonic diagnostic apparatus 1 shown in FIG.

  The image generation unit 200 includes an ultrasonic probe 2, a transmission / reception circuit 3, a signal processing circuit 4, a DSC 5, and a VR processing circuit 6, and as described above, is obtained by scanning a subject with ultrasonic waves. Voxel data is generated based on the signal, and a three-dimensional image is generated based on the voxel data. This three-dimensional image is defined using predetermined three-dimensional orthogonal coordinates (x, y, z). The image generation unit 200 corresponds to the “image generation unit” of the present invention.

[Operation section]
The operation unit 8 includes the above-described various input devices, and particularly includes a cut surface change operation unit 81 and a measurement point input operation unit 82.

  The cut surface changing operation unit 81 corresponds to “first operation means” of the present invention, and is operated by an operator to designate a cutting position of a three-dimensional image displayed on the display device 7.

  Here, the three-dimensional cut image means an image having a shape obtained by cutting a part of the three-dimensional image of the subject generated by the image generation unit 200. For example, the three-dimensional cut image G ′ shown in FIG. 3 is an image displayed on the display screen 7A of the display device 7, and is formed by the three-dimensional image G having a shape cut partially by a plane. The cut surface Ga of the three-dimensional cut image G ′ is a flat surface. Details of the processing for generating the three-dimensional cut image G ′ will be described later.

  The operator can change the cutting position of the three-dimensional cut image by operating the cut surface changing operation unit 81. That is, a three-dimensional cut image having different cut surfaces can be displayed. The cutting position is changed along the depth direction of the displayed three-dimensional image (three-dimensional cut image), for example, and the operator operates the cutting surface change operation unit 81 to change the position of the displayed cutting surface. Can be moved forward / backward. The cut surface changing operation unit 81 is constituted by a trackball or the like. When the trackball is operated forward, for example, the cut surface is moved in the depth direction of the three-dimensional cut image, and when operated to the front side, the cut surface is moved forward. The

  The measurement point input operation unit 82 of the operation unit 8 corresponds to the “second operation unit” of the present invention, and is operated to input measurement points on the cut surface Ga of the three-dimensional cut image G ′. The measurement point is input in order to designate the end point of the section where distance measurement is performed in the three-dimensional image G.

  The measurement point input operation unit 82 is constituted by a joystick, for example. A target for determining the input position of the measurement point is displayed on the display screen 7A, and the target can be moved by tilting the joystick forward / backward / left / right. The operator operates the joystick to move the target to a desired position on the cutting plane Ga, and presses a button at the tip of the joystick to specify and input the position as a measurement point.

[Data storage section]
The data storage unit 10 stores various types of data including voxel data D1 and 3D image data D2. The voxel data D1 is generated by the DSC 5 of the image generation unit 200 as described above. Further, the three-dimensional image data D2 is obtained by applying the three-dimensional image data generated by the VR processing circuit 6 as described above to the subject such as the image data of the three-dimensional image generated by the control unit 100. 3D image data generated based on data collected by ultrasonic scanning.

(Control part)
The control unit 100 controls a cut image generation unit 110 that generates a three-dimensional cut image as illustrated in FIG. 3, a calculation processing unit 120 that executes various calculation processes, and an image display process performed by the display device 7. A display control unit 130 is provided.

(Cut image generator)
The cut image generation unit 110 corresponds to the “cut image generation unit” of the present invention that generates a three-dimensional cut image having a shape obtained by cutting a part of the three-dimensional image of the subject generated by the image generation unit 200. To do. The three-dimensional cut image generated by the cut image generation unit 110 is defined by the same three-dimensional orthogonal coordinates (x, y, z) as the three-dimensional image of the subject.

  When the cutting position is specified by the cutting plane change operation unit 81, the cutting image generation unit 110 applies the MPR method to the tomographic image corresponding to the specified cutting plane to the three-dimensional image data D2 of the three-dimensional image of the subject. Generate by applying. Further, the cut image generation unit 110 displays a predetermined one of the two parts of the three-dimensional image divided by the cut surface, and the tomographic image generated by the MPR method at the position of the cut surface. A synthesized image, that is, a three-dimensional cut image is generated. Note that the operator inputs a measurement point related to the distance measurement in consideration of the state of the cut surface, so that the “predetermined one portion” is located behind the cut surface as shown in FIG. It is assumed to be the part of the direction. As a result, a three-dimensional cut image corresponding to the case where the three-dimensional image of the subject is viewed from the direction of the designated cut surface is generated and displayed.

  The cut image generation unit 110 sequentially generates a three-dimensional cut image having a cut surface at a specified cutting position each time the cut surface change operation unit 81 is operated. The sequentially generated three-dimensional cut images are sent to the display device 7 by the display control unit 130 and sequentially displayed. Thereby, the operator can observe a desired cut surface of the three-dimensional image.

  Although details will be described later, the cut image generation unit 110 also generates a three-dimensional cut image having a cut surface orthogonal to the direction of the straight line (approximate straight line) calculated by the calculation processing unit 120 by the same process. It is like that.

  In the ultrasonic diagnostic apparatus 1 of the present embodiment, a configuration for generating a three-dimensional cut image using the MPR method is employed, but any method capable of generating a similar three-dimensional cut image can be used. is there. For example, a plurality of tomographic images obtained by ultrasonic scanning are stored in the data storage unit 10, and a tomographic image corresponding to the position of the designated cutting plane is selected and synthesized into a three-dimensional image. A cut image can be generated. At this time, when the position of the designated cut surface is a position between two tomographic images, a tomographic image corresponding to the position of the cut surface is formed by interpolation processing and used as an image of the cut surface. be able to. In addition, when a cutting plane is specified in a direction different from the slice direction of a plurality of tomographic images, a known method for forming a tomographic image in a direction different from the slice direction from the plurality of tomographic images is used. Can be obtained.

(Calculation processing part)
The calculation processing unit 120 includes a straight line calculation unit 121, an approximate straight line calculation unit 122, an intersection calculation unit 123, and a distance calculation unit 124.

(Linear calculation unit)
The straight line calculation unit 121 corresponds to the “straight line calculation unit” of the present invention, and obtains a straight line connecting two measurement points input on the cut surface of the three-dimensional cut image by the measurement point input operation unit 82, that is, An expression representing a straight line is calculated. Here, the equation of the straight line is defined by the same three-dimensional orthogonal coordinates (x, y, z) as the three-dimensional cut image of the subject. More specifically, P1 = (x1, y1, z1), P2 = (x2, y2, z2) using two-dimensional orthogonal coordinates (x, y, z) for the two input measurement points P1, P2. And a straight line connecting the measurement points P1 and P2 is calculated by a well-known formula. The two measurement points may be input on a single cut surface or may be input on two different cut surfaces.

(Approximate line calculation unit)
The approximate straight line calculation unit 122 corresponds to the “approximate straight line calculation unit” of the present invention, and when three or more measurement points are input on the cut surface of the three-dimensional cut image by the measurement point input operation unit 82. Operate and obtain a straight line approximating these three or more measurement points (calculate the formula of the straight line). Here, the straight line obtained on the basis of three or more measurement points is referred to as an “approximate straight line” in order to distinguish it from a straight line connecting two measurement points. The formula of this approximate straight line is defined by the same three-dimensional orthogonal coordinates (x, y, z) as the three-dimensional cut image of the subject. When three or more points are input on a straight line, the approximate straight line is the same as the straight line calculated by the straight line calculation unit 121.

  The approximate straight line calculation unit 122 obtains an approximate straight line by, for example, one of the following methods. (1) Apply the least squares method to three or more input measurement points to find a straight line that minimizes the total error (sum of squares) from each measurement point, and use it as an approximate straight line Can do. (2) The distance between all pairs of three or more input measurement points can be compared, and a straight line connecting the two measurement points with the maximum distance can be obtained and used as an approximate straight line. That is, the second method is a method that employs a straight line connecting two measurement points with the longest distance (two measurement points farthest apart) among three or more measurement points as an approximate straight line. (3) A straight line connecting the first input measurement point and the last input measurement point among the three or more input measurement points can be obtained and used as an approximate straight line. (4) Of the three or more input measurement points, a straight line connecting the last input measurement point and the second input measurement point from the last can be obtained and used as an approximate straight line. Of course, it is possible to obtain the approximate straight line by using any method other than these four methods.

(Intersection calculator)
The intersection calculation unit 123 corresponds to the “intersection calculation unit” of the present invention, and obtains an intersection between the cut surface of the three-dimensional cut image generated by the cut image generation unit 110 and the straight line obtained by the straight line calculation unit 121. Process. In addition, the intersection calculation unit 123 performs processing for obtaining an intersection between the cut surface of the three-dimensional cut image and the approximate straight line obtained by the approximate straight line calculation unit 122.

  The cut surface of the three-dimensional cut image is defined as a plane expression using the above-described three-dimensional orthogonal coordinates (x, y, z). A straight line expression is also defined as a straight line expression using the same three-dimensional orthogonal coordinates (x, y, z). The intersection calculation unit 123 calculates the coordinates of the intersection between the plane represented by the equation defining the cut surface and the straight line using a well-known formula. The same applies to obtaining the intersection of the cut surface and the approximate straight line.

(Distance calculation unit) The distance is calculated independently of the straight line calculation. It can be obtained from the length of the straight line (line segment).
The distance calculation unit 124 corresponds to the “distance calculation unit” of the present invention, and two measurement positions of the subject specified by the two measurement points input to the three-dimensional cut image using the measurement point input operation unit 82. The process which calculates the distance between is performed. When the two input measurement points are P1 = (x1, y1, z1) and P2 = (x2, y2, z2), the distance D between P1 and P2 is a well-known formula D = {(x1 -X2) ^ 2 + (y1-y2) ^ 2 + (z1-z2) ^ 2} ^ (1/2).

  Here, a description will be given of three-dimensional orthogonal coordinates (x, y, z) used when data processing is performed on a three-dimensional image or a three-dimensional cut image. For each of the x-coordinate, y-coordinate, and z-coordinate of the three-dimensional orthogonal coordinate (x, y, z), the scale of the three-dimensional orthogonal coordinate is the scale of the real space (the three-dimensional space where the subject actually exists). Is set to a unit distance corresponding to a unit distance in real space (for example, 1 mm, 1 cm, etc.). The three-dimensional image or the three-dimensional cut image is displayed as an image obtained by enlarging / reducing the corresponding part in the actual subject, and the distance on the image and the distance in the real space are associated with each other by the enlargement / reduction magnification of the image. Yes. The unit distance of each coordinate may be displayed on the coordinate as a scale, or may not be displayed.

[Operation]
The operation of the ultrasonic diagnostic apparatus 1 having the above-described configuration will be described with reference to FIGS. FIG. 4 is a flowchart showing an example of an operation procedure of the ultrasonic diagnostic apparatus 1. The flowchart of FIG. 4 shows the operation until the fourth measurement point is input. 5 to 13 are diagrams for explaining screens displayed on the display device 7 in accordance with the operation procedure shown in the flowchart of FIG. 5A to 13A show an example of a screen displayed on the display screen 7A of the display device 7. FIG. FIGS. 5B to 13B are side sectional views of a three-dimensional image of the subject for explaining the displayed screen.

  First, an ultrasonic scan is performed on a region of interest of the subject, and a three-dimensional image G of the region of interest is generated and displayed on the display device 7 (S1). In the three-dimensional image G, the above-described three-dimensional orthogonal coordinates (x, y, z) are set.

  The operator operates the operation unit 8 to rotate or enlarge / reduce the three-dimensional image G so that the displayed three-dimensional image G is arranged appropriately for distance measurement (S2). This arrangement of the three-dimensional image G is called “front”, and FIG. 5A shows the three-dimensional image G arranged in front. FIG. 5B is a side cross-sectional view of the three-dimensional image G in the cross section A in FIG. Note that the direction and scale of the three-dimensional orthogonal coordinates (x, y, z) are converted according to the rotation and enlargement / reduction of the three-dimensional image G.

  The operator operates the cutting plane change operation unit 81 to display a three-dimensional cutting image at a desired cutting position (slice position of the slice plane) (S3). FIG. 6A shows a display mode of a three-dimensional cut image G ′ having a cut surface Ga1 at the cutting position u1. FIG. 6B shows an aspect of the cutting position u1.

  On the display screen 7A, a target T for determining the input position of the measurement point is displayed. The operator operates the measurement point input operation unit 82 to move the target T, and inputs the first measurement point P1 at a desired position on the cutting plane Ga1 (S4). FIG. 7A shows a display mode when the first measurement point P1 is input. The input coordinates (x1, y1, z1) of the first measurement point P1 are stored in the data storage unit 10.

  Next, the operator operates the cut surface changing operation unit 81 to move the cut position of the three-dimensional cut image G ′ to a desired position (S5). For example, the cutting position is moved in a certain direction as shown in FIG. 8B (that is, the cutting surface is moved in parallel). FIG. 8A shows a display mode when the cutting position is moved to the cutting position u2, and shows a three-dimensional cutting image G ′ having a cutting surface Ga2 at the cutting position u2.

  The operator operates the measurement point input operation unit 82 to move the target T, and inputs the second measurement point P2 at a desired position on the cutting plane Ga2 (S6). FIG. 9A shows a state where the second measurement point P2 is input. The input coordinates (x2, y2, z2) of the second measurement point P2 are stored in the data storage unit 10.

  The distance calculation unit 124 uses the coordinates (x1, y1, z1) of the first measurement point P1 input on the cutting plane Ga1 and the coordinates (x2, y2) of the second measurement point P2 input on the cutting plane Ga2. Based on y2, z2), the distance between the two measurement positions of the subject specified by the first measurement point P1 and the second measurement point P2 is calculated (S7).

  The straight line calculation unit 121 also determines these measurement points P1 based on the coordinates (x1, y1, z1) of the first measurement point P1 and the coordinates (x2, y2, z2) of the second measurement point P2. , P2 is calculated (S8).

  The cut image generation unit 110 obtains an expression of a plane that is orthogonal to the calculated straight line L1 and includes the second measurement point P2, and generates a three-dimensional cut image G ′ having the plane as the cut plane. (S9). The plane corresponds to the cutting position v1 shown in FIG. 10B, and the cutting plane corresponds to the cutting plane Ga2 ′ shown in FIG.

  The operator operates the cutting plane changing operation unit 81 to move the cutting position of the three-dimensional cut image G ′ to a desired position (S10). The cutting position is moved in a certain direction as shown in FIG.

  At this time, the intersection calculation unit 123 calculates the coordinates of the intersection between the straight line L1 obtained in step S8 and each cutting plane changed by the cutting plane change operation unit 81 (S11), and the cutting is sequentially changed. A marker M indicating the position of the intersection of the cut surface and the straight line L1 is displayed on the surface (S12).

  FIG. 11A shows a display mode when the cutting position is moved to the cutting position v2, and shows a three-dimensional cutting image G ′ having a cutting surface Ga3 at the cutting position v2. The target T is displayed together with the marker M on the cut surface Ga3 of the three-dimensional cut image G ′.

  The operator operates the measurement point input operation unit 82 to move the target T, and inputs the third measurement point P3 at a desired position on the cutting plane Ga3 (S13). FIG. 12A shows a state in which the third measurement point P3 is input. The input coordinates (x3, y3, z3) of the third measurement point P3 are stored in the data storage unit 10.

  The distance calculation unit 124 calculates the coordinates (x2, y2, z2) of the second measurement point P2 input on the cutting plane Ga2 and the coordinates (x3, x2) of the third measurement point P3 input on the cutting plane Ga3. Based on y3, z3), the distance between the two measurement positions of the subject specified by the second measurement point P2 and the third measurement point P3 is calculated (S14). At this time, the first measurement point P1 and the third measurement point are based on the coordinates (x1, y1, z1) of the first measurement point P1 and the coordinates (x3, y3, z3) of the third measurement point P3. The distance between the two measurement positions of the subject specified by P3 may also be calculated.

  The control unit 100 compares the coordinates of the third measurement point P3 with the coordinates of the marker M on the cutting plane Ga3, and determines whether or not the third measurement point P3 is input on the marker M (S15). ).

  When the third measurement point P3 is input on the marker M (S15; Y), when the operator operates the cutting surface change operation unit 81, the cutting position is moved as it is in the same direction as the cutting positions v1 to v2, The fourth measurement point P4 is input (S18).

  On the other hand, when the third measurement point P3 is input at a position different from the marker M (S15; N), the approximate line calculation unit 122 calculates the coordinates (x1, y1, z1) of the first measurement point P1, and Based on the coordinates (x2, y2, z2) of the second measurement point P2 and the coordinates (x3, y3, z3) of the third measurement point P3, these three measurement points P1, P2, P3 are approximated. The approximate straight line L2 is calculated (S16). An approximate straight line L2 shown in FIG. 13B is a straight line obtained by applying the least square method to these three measurement points P1, P2, and P32.

  The cut image generation unit 110 obtains a formula of a plane that is orthogonal to the calculated approximate straight line L2 and includes the third measurement point P3, and generates a three-dimensional cut image G ′ having the plane as the cut plane. (S17). Note that the plane corresponds to the cutting position w1 illustrated in FIG.

  The operator operates the cutting surface changing operation unit 81 to move the cutting position (parallel to w1) of the three-dimensional cutting image G ′ to a desired position, and inputs the fourth measurement point P4 (S18). . At this time, a marker indicating the position of the intersection between the approximate straight line L2 and the cut surface is displayed on the moved cut surface.

  The process accompanying the input after the fourth measurement point P4 is the same as the process for the third measurement point P3 (steps S13 to S17).

[Function and effect]
The effect which the ultrasonic diagnostic apparatus 1 of this embodiment which performs the above operations demonstrates will be described.

  According to the ultrasonic diagnostic apparatus 1 of the present embodiment, when a section for distance measurement is designated, an image obtained by processing a three-dimensional image of a region of interest of a subject is used instead of displaying a three-view diagram as in the prior art. Is displayed. More specifically, by displaying a three-dimensional cut image of a shape obtained by cutting a part of the three-dimensional image of the region of interest and inputting a plurality of measurement points while moving the cut position, that is, changing the cut surface The section for distance measurement is designated.

  Comparing such a configuration of the present embodiment with the conventional configuration, conventionally, it has been necessary to display various three views in order to find a cross section suitable for distance measurement. An appropriate cross section can be found by simply changing the cut surface of the dimension cut image. Moreover, even if a cross-section that seems to be appropriate is actually unintentional, it is possible to find an appropriate cross-section only by changing the cut surface of the three-dimensional cut image. Thereby, according to this embodiment, there exists an advantage that designation | designated operation of the area which measures distance can be performed simply and rapidly.

  Further, according to the present embodiment, since the section can be designated as it is on the acquired three-dimensional image (a three-dimensional cut image obtained by processing), the operability in distance measurement is good and the measurement time can be shortened. it can.

  Also, if a display device with the same screen size is installed, the section can be specified using an image with a size larger than the conventional three-view screen that displays the image by dividing the display screen. It is possible to improve the performance and speed up the operation. In addition, since measurement points for specifying a section can be input on a large and detailed image, measurement accuracy can be improved.

  Further, according to the present embodiment, when the cutting position of the three-dimensional cut image is moved, a marker indicating the position of the intersection between the cut surface and a straight line (or an approximate straight line) is displayed on the cut surface. This makes it possible to clearly indicate to the operator the position on the extension of the previously input measurement point, making it easy to determine the input position of a new measurement point and simplifying the operation for specifying the section for distance measurement. And speeding up.

  Further, according to the present embodiment, in response to the input of the second measurement point, the orientation of the cut surface of the displayed three-dimensional cut image is orthogonal to the straight line connecting the first and second measurement points. The direction is changed. Further, the moving direction of the cutting position of the three-dimensional cut image is also changed to the direction of the straight line. Thereby, the operator can input a new measurement point by observing the cutting plane orthogonal to the direction in which the distance measurement is performed, and can move the cutting position in the direction in which the distance measurement is performed. it can. Therefore, the input position of a new measurement point can be easily determined, and the section designation operation can be performed easily and quickly.

  Similarly, in response to the input of the third measurement point, the orientation of the cut surface of the displayed three-dimensional cut image is changed to the direction of the approximate line that approximates the first to third measurement points. In addition, since the moving direction of the cutting position of the three-dimensional cutting image is also changed to the direction of this approximate straight line, the input position of a new measurement point can be easily determined. Therefore, it is possible to simplify and speed up the section designation operation.

  The configuration described in detail above is only an example for suitably implementing the ultrasonic diagnostic apparatus according to the present invention. Therefore, arbitrary modifications within the scope of the gist of the present invention can be made as appropriate.

  For example, in the above embodiment, in response to the change of the cutting position of the three-dimensional cut image, a three-dimensional cut image having a cut surface at the changed cutting position is generated. The timing for generating the three-dimensional cut image is not limited to this. For example, when the movement direction of the cutting position is determined, that is, (1) before the input of the second measurement point, the movement direction is determined in advance, (2) after the input of the second measurement point and When a straight line connecting the first and second measurement points is obtained before inputting the third measurement point, (3) an approximate straight line is obtained after the measurement points after the third measurement point are inputted. When the cut surface is moved, images of a number of cut surfaces orthogonal to the determined moving direction are generated in the background, and when the cut surface is moved, the image of the cut surface and the three-dimensional image are synthesized. Thus, a three-dimensional cut image can be generated. As a result, the time required for generating the three-dimensional cut image can be shortened.

  In the above embodiment, only the case of calculating the distance between the measurement positions of the subject specified by two measurement points input on different cutting planes has been described. It is also possible to calculate the distance corresponding to the two measured points.

1 is a block diagram illustrating an example of the overall configuration of an embodiment of an ultrasonic diagnostic apparatus according to the present invention. It is a block diagram showing an example of composition of a control system of an embodiment of an ultrasonic diagnostic equipment concerning the present invention. It is the schematic showing an example of the three-dimensional cut image displayed by embodiment of the ultrasonic diagnosing device which concerns on this invention. It is a flowchart showing an example of operation | movement of embodiment of the ultrasonic diagnosing device which concerns on this invention. It is a figure for demonstrating the screen displayed by embodiment of the ultrasound diagnosing device which concerns on this invention. FIG. 5A shows an example of a display screen. FIG. 5B is a side sectional view of a three-dimensional image for explaining the display screen. It is a figure for demonstrating the screen displayed by embodiment of the ultrasound diagnosing device which concerns on this invention. FIG. 6A shows an example of a display screen. FIG. 6B is a side sectional view of a three-dimensional image for explaining the display screen. It is a figure for demonstrating the screen displayed by embodiment of the ultrasound diagnosing device which concerns on this invention. FIG. 7A shows an example of a display screen. FIG. 7B is a side sectional view of a three-dimensional image for explaining the display screen. It is a figure for demonstrating the screen displayed by embodiment of the ultrasound diagnosing device which concerns on this invention. FIG. 8A shows an example of a display screen. FIG. 8B is a side sectional view of a three-dimensional image for explaining the display screen. It is a figure for demonstrating the screen displayed by embodiment of the ultrasound diagnosing device which concerns on this invention. FIG. 9A shows an example of a display screen. FIG. 9B is a side sectional view of a three-dimensional image for explaining the display screen. It is a figure for demonstrating the screen displayed by embodiment of the ultrasound diagnosing device which concerns on this invention. FIG. 10A shows an example of a display screen. FIG. 10B is a side sectional view of a three-dimensional image for explaining the display screen. It is a figure for demonstrating the screen displayed by embodiment of the ultrasound diagnosing device which concerns on this invention. FIG. 11A illustrates an example of a display screen. FIG. 11B is a side sectional view of a three-dimensional image for explaining the display screen. It is a figure for demonstrating the screen displayed by embodiment of the ultrasound diagnosing device which concerns on this invention. FIG. 12A shows an example of a display screen. FIG. 12B is a side sectional view of a three-dimensional image for explaining the display screen. It is a figure for demonstrating the screen displayed by embodiment of the ultrasound diagnosing device which concerns on this invention. FIG. 13A shows an example of a display screen. FIG. 13B is a side sectional view of a three-dimensional image for explaining the display screen. It is the schematic showing an example of the three-surface figure displayed by the conventional ultrasonic diagnostic apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ultrasonic diagnostic apparatus 2 Ultrasonic probe 3 Transmission / reception circuit 4 Signal processing circuit 5 DSC (digital scan converter)
6 VR (volume rendering) processing circuit 7 display device 7A display screen 8 operation unit 81 cutting surface change operation unit 82 measurement point input operation unit 9 printing device 10 data storage unit D1 voxel data D2 3D image data 100 control unit 110 cut image Generation unit 120 Calculation processing unit 121 Line calculation unit 122 Approximate line calculation unit 123 Intersection point calculation unit 124 Distance calculation unit 130 Display control unit G 3D image G ′ 3D cut image Ga, Ga1, Ga2, Ga2 ′, Ga3 cut surface u1 , U2, v1, v2, w1 Cutting positions P1, P2, P3 Measuring point L1 Straight line L2 Approximate straight line T Target

Claims (8)

Image generating means for generating voxel data based on a received signal obtained by scanning a subject with ultrasound, and generating a three-dimensional image based on the voxel data;
Display means for displaying the generated three-dimensional image;
First operating means for designating a cutting position of the displayed three-dimensional image;
A cut image generating means for generating a three-dimensional cut image composed of the three-dimensional image cut at the designated cutting position;
Second operating means for inputting measurement points on the cut surface of the three-dimensional cut image generated and displayed on the display means;
Distance calculating means for calculating a distance between two measurement positions of the subject specified by the two input measurement points;
An ultrasonic diagnostic apparatus comprising: The cut image generation unit sequentially generates a plurality of three-dimensional cut images having different cut positions in the depth direction of the displayed three-dimensional image in response to an operation from the first operation unit;
The display means sequentially displays the sequentially generated plural three-dimensional cut images;
The ultrasonic diagnostic apparatus according to claim 1. Straight line calculating means for obtaining a straight line connecting the two measurement points input by the second operating means;
Intersection calculation means for obtaining an intersection between the cut surface of the three-dimensional cut image generated by the cut image generation means and the obtained straight line;
Further comprising
The display means displays a marker indicating the position of the obtained intersection on the cut surface.
The ultrasonic diagnostic apparatus according to claim 1 or claim 2, wherein The cut image generating means generates a three-dimensional cut image having a cut surface that is orthogonal to the straight line obtained by the straight line calculating means and includes one of the two measurement points,
The display means displays the generated three-dimensional cut image.
The ultrasonic diagnostic apparatus according to claim 3. The cut image generation means sequentially generates a plurality of three-dimensional cut images having cut surfaces orthogonal to the straight line at different positions on the straight line in response to an operation from the first operating means.
The display means sequentially displays the sequentially generated plurality of three-dimensional cut images.
The ultrasonic diagnostic apparatus according to claim 4. When the new measurement point is input at a position different from the marker on the cut surface of the three-dimensional cut image, the two measurement points connected by the straight line and the new measurement point are included. An approximate straight line calculating means for obtaining an approximate straight line that approximates two or more measurement points;
The intersection calculation means obtains a new intersection where the cut surface of the three-dimensional cut image generated by the cut image generation means and the obtained approximate line intersect,
The display means displays a new marker indicating the position of the determined new intersection on the cut surface;
The ultrasonic diagnostic apparatus according to claim 3, wherein the ultrasonic diagnostic apparatus is characterized. The cut image generating means generates a three-dimensional cut image having a cut surface perpendicular to the approximate straight line and having a cut surface including any of the three or more measurement points,
The display means displays the generated three-dimensional cut image.
The ultrasonic diagnostic apparatus according to claim 6. The cut image generation means sequentially generates a plurality of three-dimensional cut images having cut surfaces orthogonal to the approximate line at different positions on the approximate line in response to an operation from the first operation means.
The display means sequentially displays the sequentially generated plurality of three-dimensional cut images;
The ultrasonic diagnostic apparatus according to claim 7.

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