Image processing device, method, and program

Abstract

To provide image processing device, method, and program capable of analyzing tissue of interest by component.SOLUTION: An image processing device for processing an image acquired by an X-ray computer tomography apparatus capable of measuring an effective atomic number includes a processor. The processor displays at least one of a plurality of images acquired by the X-ray computer tomography apparatus in a display unit, receives settings of a first region on an image displayed in the display unit, receives settings of an effective atomic number, which is an object to be analyzed, extracts a pixel including a component of the effective atomic number in the first region, extracts a second region including a component of the effective atomic number in the first region, specifies the shape of the second region, and displays the shape of the second region in the display unit.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an image processing device, method, and program, and more particularly to an image processing device, method, and program for processing images obtained by an X-ray computed tomography device (X-ray CT device) capable of measuring effective atomic number. [Background technology]

[0002] Patent Document 1 describes a technique for identifying possible pulmonary nodules from images acquired by an X-ray CT apparatus and determining their shapes and the like. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-147930 Summary of the Invention [Problem to be solved by the invention]

[0004] In diseases that cause stones, such as ureteral stones, treatments and prevention methods vary depending on the components of the stones. However, the technology described in Patent Document 1 cannot analyze the shape and other characteristics of the tissue of interest for each component.

[0005] One embodiment of the technique of the present disclosure provides an image processing device, method, and program capable of analyzing a tissue of interest for each component. [Means for solving the problem]

[0006] (1) An image processing device that processes images obtained by an X-ray computed tomography device capable of measuring effective atomic number, comprising a processor, the processor displays at least one of multiple images obtained by the X-ray computed tomography device on a display unit, accepts the setting of a first region on the image displayed on the display unit, accepts the setting of the effective atomic number to be analyzed, extracts pixels containing components of the effective atomic number within the first region, extracts a second region containing components of the effective atomic number within the first region, identifies the shape of the second region, and displays the shape of the second region on the display unit.

[0007] (2) The image processing device according to (1), wherein the processor measures the size of the second region and displays the shape and size of the second region on the display unit.

[0008] (3) The image processing device according to (1) or (2), wherein the processor accepts a setting of a range of effective atomic numbers to be analyzed.

[0009] (4) The image processing device according to (3), wherein the processor accepts a value of the reference effective atomic number and a setting of a range based on the value, and accepts a setting of a range of the effective atomic number to be analyzed.

[0010] (5) An image processing device according to any one of (1) to (4), wherein the processor displays pre-registered effective atomic numbers on the display unit as effective atomic numbers corresponding to specific components, accepts a selection from the effective atomic numbers displayed on the display unit, and accepts the setting of the effective atomic number to be analyzed.

[0011] (6) The image processing device according to (5), wherein the processor associates information about components corresponding to effective atomic numbers with the effective atomic numbers and displays the information on the display unit.

[0012] (7) The image processing device according to (5) or (6), wherein the processor accepts registration of an effective atomic number to be displayed on the display unit.

[0013] (8) An image processing device described in any one of (1) to (7), wherein the processor accepts multiple settings of the first region, accepts settings of the effective atomic number to be analyzed for each first region, extracts a second region for each first region, identifies the shape of the second region for each first region, and displays the shape of the second region for each first region on a display unit.

[0014] (9) The image processing device according to (8), wherein the processor measures the size of the second region for each first region and displays the shape and size of the second region for each first region on the display unit.

[0015] (10) An image processing device described in any one of (1) to (9), wherein the processor accepts the setting of the range of images to be analyzed from among multiple images obtained by an X-ray computed tomography device, extracts a second region individually from the images within the set range, identifies the three-dimensional shape of the second region, and displays the three-dimensional shape of the second region on a display unit.

[0016] (11) The image processing device according to (10), wherein the processor measures the volume of the second region, measures the size of the second region, and displays the three-dimensional shape and volume of the second region on the display unit.

[0017] (12) An image processing device described in (10) or (11), in which the processor displays a three-dimensional image generated from multiple images obtained by an X-ray computed tomography device on a display unit and accepts the setting of a first area on the three-dimensional image displayed on the display unit.

[0018] (13) An image processing device described in any one of (1) to (12), wherein the processor displays the three-dimensional shape of the second region on a three-dimensional image generated from multiple images obtained by an X-ray computed tomography device.

[0019] (14) The image processing device according to any one of (1) to (13), wherein the X-ray computed tomography device is an X-ray computed tomography device capable of photon counting computed tomography.

[0020] (15) The image processing device according to any one of (1) to (14), wherein the multiple images obtained by the X-ray computed tomography device are effective atomic number images.

[0021] (16) An image processing method for processing an image obtained by an X-ray computed tomography device capable of measuring effective atomic number, the image processing method comprising: displaying at least one of a plurality of images obtained by the X-ray computed tomography device on a display unit; accepting the setting of a first region on the image displayed on the display unit; accepting the setting of the effective atomic number to be analyzed; extracting pixels containing a component of the effective atomic number within the first region; extracting a second region containing a component of the effective atomic number within the first region; identifying the shape of the second region; and displaying the shape of the second region on the display unit.

[0022] (17) An image processing program for processing images obtained by an X-ray computed tomography device capable of measuring effective atomic number, the image processing program causing a computer to realize the following functions: displaying at least one of multiple images obtained by the X-ray computed tomography device on a display unit; accepting the setting of a first region on the image displayed on the display unit; accepting the setting of the effective atomic number to be analyzed; extracting pixels containing components of the effective atomic number within the first region and extracting a second region containing components of the effective atomic number within the first region; identifying the shape of the second region; and displaying the shape of the second region on the display unit. [Effects of the Invention]

[0023] According to the present invention, a tissue of interest can be analyzed component by component. [Brief explanation of the drawings]

[0024] [Figure 1] PCCT device schematic diagram [Figure 2] A diagram showing an example of the console hardware configuration [Figure 3] Block diagram of the console's main functions for generating tomographic images [Figure 4] Conceptual diagram of analysis function [Figure 5] Block diagram of the console's main analytical functions [Figure 6] FIG. 10 is a diagram showing an example of a display screen of an effective atomic number image. [Figure 7] An example of the analysis condition setting screen (analysis condition setting dialog) [Figure 8] A diagram showing an example of the analysis target area setting screen [Figure 9] FIG. 10 is a diagram showing an example of a display of an area setting frame. [Figure 10] An example of the analysis results displayed on the screen [Figure 11] 10 is a flowchart showing an operation procedure when performing a process for analyzing the shape and size of a specific tissue. [Figure 12] An example of the screen display when setting the analysis target area on a 3D image. [Figure 13] An example of the analysis condition setting screen (analysis condition setting dialog) when setting the effective atomic number using a preset [Figure 14] An example of the screen for setting the effective atomic number using a preset (effective atomic number setting dialog box) [Figure 15] An example of the analysis condition setting screen (Analysis Condition Setting Dialog D) when setting the effective atomic number with a certain range. [Figure 16] Another example of the analysis condition setting screen when setting the effective atomic number with a certain range. [Figure 17] An example of outputting analysis results superimposed on the original 3D image. [Figure 18] A diagram showing an example of displaying size measurement results when outputting analysis results superimposed on the original 3D image. DETAILED DESCRIPTION OF THE INVENTION

[0025] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings.

[0026] [PCCT device] Here, an example will be described in which the present invention is applied to an X-ray computed tomography apparatus (PCCT apparatus) capable of photon counting computed tomography (PCCT).

[0027] Figure 1 is a schematic diagram of a PCCT device. In Figure 1, the X-axis, Y-axis, and Z-axis are three axes that are perpendicular to one another. The Y-axis and Z-axis directions are horizontal, and the X-axis direction is vertical (up-down). The Z-axis direction is the body axis direction.

[0028] 1, the PCCT apparatus 1 includes a scanner gantry 10, a bed 20, and a console 30. Each apparatus is connected to each other so as to be able to communicate with each other.

[0029] [Scanner Gantry] The scanner gantry 10 has an opening (bore) and performs PCCT scanning by irradiating X-rays onto a subject P inserted into the opening 10A. The scanner gantry 10 includes an X-ray tube device 11, an X-ray detection device 12, a data acquisition system (DAS) 13, a rotating frame 14, etc.

[0030] The X-ray tube device 11 irradiates the subject P with X-rays. The X-ray tube device 11 includes an X-ray tube, an X-ray high voltage device, a bowtie filter, a collimator, etc. The X-ray tube, which is an X-ray source, receives a high voltage from the X-ray high voltage device and outputs X-rays. The X-rays output from the X-ray tube are irradiated onto the subject P via the bowtie filter and the collimator.

[0031] The X-ray detection device 12 detects X-rays emitted from the X-ray tube device 11 and transmitted through the subject P. The X-ray detection device 12 is a photon-counting type X-ray detection device. A photon-counting type X-ray detection device outputs an electrical signal corresponding to the number of photons as an X-ray detection signal. The X-ray detection device 12 has a structure in which, for example, a plurality of detection elements are two-dimensionally arranged in the channel direction (circulation direction) and the column direction (body axis direction).

[0032] The data collection system 13 collects electrical signals output from each detection element of the X-ray detection device 12 and generates detection data. The detection data is data in which a count value (count number) of X-ray photons is assigned to each energy bin. An energy bin is a section that divides the X-ray spectrum by a certain energy bandwidth. The detection data generated by the data collection system 13 is output to the console 30.

[0033] The rotating frame 14 has a cylindrical shape and is driven by a rotation drive device (not shown) to rotate about its axis. The inner periphery of the rotating frame 14 forms the opening 10A of the scanner gantry 10. The X-ray tube assembly 11 and the X-ray detection assembly 12 are mounted on the rotating frame 14. The X-ray tube assembly 11 and the X-ray detection assembly 12 are disposed opposite each other with the opening 10A in between. By rotating the rotating frame 14, the X-ray tube assembly 11 and the X-ray detection assembly 12 rotate about the rotation axis of the rotating frame 14. The rotation axis of the rotating frame 14 forms the center of imaging.

[0034] [bed] The bed 20 has the subject P placed thereon and moves up and down and horizontally. The bed 20 is equipped with a top 21 on which the subject P is placed. The top 21 is driven by a vertical drive device (not shown) to move up and down in the vertical direction. The top 21 is also driven by a horizontal drive device (not shown) to move horizontally in the body axis direction (Z-axis direction). By moving the top 21 up and down, the vertical position (height) of the subject P is adjusted. By moving the top 21 horizontally along the body axis direction, the subject P moves within the opening 10A of the scanner gantry 10 along the body axis direction.

[0035] [console] The console 30 functions as an operation desk and also as an image processing device that performs various types of image processing.

[0036] FIG. 2 is a diagram illustrating an example of a hardware configuration of a console.

[0037] The console 30 is configured as a computer, and includes a processor 31, a main memory device 32, an auxiliary memory device 33, an input device 34, a display device 35, an input / output interface 36, and the like.

[0038] For example, a CPU (Central Processing Unit), which is a general-purpose processor that executes programs and functions as various processing units, is employed as the processor 31. The various programs and data executed by the processor 31 are stored in the main storage device 32 and / or the auxiliary storage device 33. The term "program" is synonymous with "software."

[0039] The main memory device 32 includes a RAM (Random Access Memory) and a ROM (Read Only Memory).

[0040] The auxiliary storage device 33 is configured, for example, by a hard disk drive (HDD), a solid state drive (SSD), or the like.

[0041] The input device 34 includes, for example, a keyboard, a mouse, a touch panel, and the like.

[0042] The display device 35 is configured by, for example, a liquid crystal display (LCD), an organic electroluminescence diode display (OLED display), etc. In the present embodiment, the display device 35 is an example of a display unit.

[0043] The input / output interface 36 communicatively connects the console 30 with the scanner gantry 10 and the bed 20 .

[0044] [Function as an operation console] Based on operation input from the user, the console 30 controls the overall operation of the PCCT apparatus 1. Setting of imaging conditions, setting of reconstruction processing, setting of analysis conditions, etc. is performed via the console 30.

[0045] [Image processing function] (a) Function to generate tomographic images In addition to conventional cross-sectional images (CT images) showing the distribution of linear attenuation coefficients, the detection data obtained by PCCT can also produce spectral images containing a variety of information, such as virtual monochromatic X-ray images, effective atomic number images, and material decomposition images. A virtual monochromatic X-ray image is a virtual representation of an image obtained with a single energy. An effective atomic number image is an image that shows the distribution of a substance's effective atomic number (effective Z). The effective atomic number is the atomic number equivalent to the average atomic number of the constituent elements of a compound or mixture. In an effective atomic number image, the effective atomic number is displayed for each pixel. A material decomposition image is an image that shows the distribution of a substance's density value. In a material decomposition image, the density value of a substance is displayed for each pixel.

[0046] FIG. 3 is a block diagram of the main functions of the console regarding the generation of tomographic images.

[0047] The console 30 has functions such as a data acquisition unit 31A, an image processing unit 31B, a recording control unit 31C, and an output control unit 31D. The functions of each unit are realized by the processor 31 executing a predetermined program.

[0048] The data acquisition unit 31A acquires X-ray detection data from the scanner gantry 10. As described above, the detection data is data in which the count value of X-ray photons is assigned to each energy bin. The detection data includes information such as the channel number of the detection element, the column number, the view number indicating the acquired view, and the count value of the detected X-ray photons for each energy bin.

[0049] The image processing unit 31B generates a tomographic image by performing a predetermined reconstruction process on the detection data acquired by the data acquisition unit 31A. In addition, the image processing unit 31B generates spectral images such as a virtual monochromatic X-ray image, an effective atomic number image, and a material decomposition image in response to an instruction from a user. Each image is generated for each slice.

[0050] The recording control unit 31C records the tomographic images (including spectral images) generated by the image processing unit 31B in the auxiliary storage device 33. The images are recorded on an examination basis. That is, multiple tomographic images obtained in one examination are recorded in association with each other. Furthermore, each tomographic image is recorded in association with the detection data from which it was generated.

[0051] The output control unit 31D outputs the tomographic images (including spectral images) generated by the image processing unit 31B to the display device 35. The output control unit 31D also outputs the recorded tomographic images to the display device 35. The tomographic images are displayed in a predetermined format.

[0052] (b) Analysis function The console 30 of this embodiment has a function of analyzing the shape and size of a specific tissue (analysis function) as a function of supporting image interpretation.

[0053] 4 is a conceptual diagram of the analysis function, in which (A) is a conceptual diagram of setting analysis conditions, and (B) is a diagram showing an example of displaying the analysis results.

[0054] Analysis of the shape and size of specific tissues is performed using effective atomic number images.

[0055] As shown in Fig. 4(A), the user sets a region to be analyzed (analysis region) S on the effective atomic number image Zeff. The analysis region S is synonymous with a region of interest (ROI).

[0056] The user also sets the tissue components to be analyzed and the image range.

[0057] The components of the tissue to be analyzed are set by the effective atomic number, i.e., the effective atomic number corresponding to the components of the tissue to be analyzed is set.

[0058] The image range is set by the slice number, which is a serial number given to each tomographic image in the order of capture (scan).

[0059] The console 30 analyzes the effective atomic number images of the set image range and extracts tissue regions having the set components from the analysis target region of each image. The extraction is performed by extracting pixels containing the set effective atomic number components. The console 30 identifies the three-dimensional shape of the tissue based on the extraction results from each image and measures its volume. Then, information on the identified shape and measured volume is output as the analysis results. Figure 4(B) shows an example of a case where the three-dimensional shape of the tissue is displayed three-dimensionally as the analysis results.

[0060] In this way, the effective atomic number image is used to extract tissues having a set component (effective atomic number), determine their shape and size, and display the results. This allows, for example, the shape and size of stones, etc., to be identified for each component.

[0061] FIG. 5 is a block diagram of the main functions of the console regarding the analysis function.

[0062] 5, with regard to the analysis function, the console 30 has functions such as an analysis condition receiving unit 31E, an image acquiring unit 31F, an image analyzing unit 31G, an analysis result processing unit 31H, and an output control unit 31D. The functions of each unit are realized by the processor 31 executing a predetermined program (image processing program).

[0063] (a) Analysis condition reception section The analysis condition receiving unit 31E receives settings of analysis conditions from the user. Specifically, it receives settings of the region to be analyzed (analysis target region), the components of the tissue to be analyzed (effective atomic number), and the image range from the user. Multiple analysis target regions can be set. When multiple analysis target regions are set, analysis conditions (effective atomic number and image range) are set for each analysis target region. In this embodiment, the analysis target region is an example of a first region.

[0064] The analysis condition receiving unit 31E displays a predetermined setting screen on the display device 35 and receives the setting of the analysis conditions from the user.

[0065] 6 to 9 are diagrams showing examples of screen displays when setting analysis conditions. FIG. 6 is a diagram showing an example of a display screen for an effective atomic number image. FIG. 7 is a diagram showing an example of an analysis condition setting screen (analysis condition setting dialog). FIG. 8 is a diagram showing an example of an analysis target region setting screen. FIG. 9 is a diagram showing an example of a display frame for setting an analysis target region (region setting frame).

[0066] In the PCCT device 1 of this embodiment, a function (analysis function) for analyzing the shape and size of a specific tissue is provided as an analysis menu for an effective atomic number image.

[0067] As shown in FIG. 6, an image display area V1 and a menu display area V2 are set on the display screen of the effective atomic number image.

[0068] In the image display area V1, effective atomic number images Zeff_1 to Zeff_4 are displayed. In the example shown in FIG. 6, four effective atomic number images Zeff_1 to Zeff_4 are displayed at one time. The number of images displayed at one time is not limited to this, and for example, only one image may be displayed. In the image display area V1, an image next button B11 and an image previous button B12 are displayed. By clicking the image next button B11 or the image previous button B12, the images displayed in the image display area V1 are switched one by one. Note that a configuration in which multiple images (for example, four) are switched at one time may also be used. The images are displayed in order of slice number and are switched in order of slice number.

[0069] In the menu display area V2, buttons for analysis items that can be performed on the image displayed in the image display area V1 are displayed. Since the PCCT device 1 of this embodiment is capable of analyzing the shape and size of a specific tissue, a button for this function (shape and size analysis button) B21 is displayed in the menu display area V2. To analyze the shape and size of a specific tissue, the user clicks the shape and size analysis button B21 displayed in the menu display area V2.

[0070] When the shape and size analysis button B21 is clicked, a dialog box (analysis condition setting dialog box) D for setting analysis conditions pops up on the screen.

[0071] As shown in Figure 7, the analysis condition setting dialog D has a sheet (analysis condition setting sheet) DS for setting analysis conditions for each area to be analyzed. Figure 7 shows an example where analysis target areas have been set in three locations. The displayed sheet can be switched using tab PT. Figure 7 shows an example where the analysis condition setting sheet DS for "Analysis 1" has been selected.

[0072] The analysis condition setting sheet DS has a field C1 for setting whether the analysis is valid or invalid, a field C2 for setting the image range, and a field C3 for setting the effective atomic number.

[0073] A check box C11 is provided in the field C1 for setting whether to enable or disable the analysis. Checking the check box C11 enables the analysis.

[0074] The field C2 for setting the image range includes a text box C21 for inputting the start point of the image range and a text box C22 for inputting the end point. The text box C21 for inputting the start point of the image range inputs the slice number of the effective atomic number image that is the start of the image range. The text box C22 for inputting the end point of the image range inputs the slice number of the effective atomic number image that is the end of the image range. Figure 7 shows an example in which the second to sixth effective atomic number images are the analysis targets. For example, "1" is automatically entered as the default value in the text box C21 for inputting the start point of the image range. Furthermore, for example, the slice number of the last effective atomic number image is automatically entered as the default value in the text box C22 for inputting the end point of the image range. In other words, the entire range of effective atomic number images is the analysis target as the default setting. The user can change the values ​​in the text boxes as needed to narrow down the image range to be analyzed. It is also possible to specify only one image range. When specifying only one image, enter the slice number of the image to be analyzed in only one text box C21, and leave the other text box C22 blank.

[0075] The effective atomic number setting field C3 is provided with a text box C31 for inputting the effective atomic number. Figure 7 shows an example in which "2.00" is set as the effective atomic number of the analysis target.

[0076] As described above, multiple regions to be analyzed can be set. The analysis condition setting dialog D is provided with a button (add button) DB1 for adding an analysis condition setting sheet DS, and a button (delete button) DB2 for deleting an analysis condition setting sheet DS. The default number of analysis condition setting sheets DS displayed is 1. Each time the add button DB1 is clicked, an analysis condition setting sheet DS is added. Also, when the delete button DB2 is clicked, the analysis condition setting sheet DS currently being displayed is deleted.

[0077] The analysis condition setting sheet DS is given the name of the analysis (analysis name) as the sheet name. The analysis names are automatically generated in the order in which the sheets are created, as "Analysis 1", "Analysis 2", ..., "Analysis N" (N = 1, 2, ...). The analysis names (sheet names) are displayed on the tab PT of each analysis condition setting sheet DS.

[0078] When the checkbox C11 in the column C1 for enabling or disabling the analysis is checked and the analysis is enabled, frames (region setting frames) F1 to F3 for setting the region to be analyzed are displayed on the effective atomic number image displayed in the image display area V1, as shown in FIG. 8. The region setting frames F1 to F3 are displayed for images within the set image range. FIG. 8 shows an example in which the second to sixth effective atomic number images (effective atomic number images with slice numbers 2 to 6) are set as the analysis targets for all regions to be analyzed. In this case, the region setting frames F1 to F3 are displayed on the second to fourth effective atomic number images Zeff_2 to Zeff_4 of the effective atomic number images Zeff_1 to Zeff_4 (effective atomic number images with slice numbers 1 to 4) displayed in the image display area V1.

[0079] FIG. 9 is a diagram showing an example of the display of the area setting frame.

[0080] The region setting frames F1 to F3 are initially displayed as circles of a predetermined size and are displayed in the center of the image. The user adjusts the position, size, and shape (aspect ratio of an ellipse) of the region setting frames F1 to F3 displayed as circles to set the region to be analyzed at any position. The position, size, and shape are adjusted using, for example, a mouse. The position, size, and shape can be adjusted for any image in which the region setting frames F1 to F3 are displayed. For example, in the example shown in FIG. 8, the region setting frames F1 to F3 can be adjusted for any of the second to fourth effective atomic number images Zeff_2 to Zeff_4. Adjustments made on one image are reflected in the other images.

[0081] Each of the region setting frames F1 to F3 displays a number corresponding to the analysis name on the analysis condition setting sheet DS. In FIG. 9, the first region setting frame F1 corresponds to the analysis condition setting sheet for "Analysis 1." The second region setting frame F2 corresponds to the analysis condition setting sheet for "Analysis 2." The third region setting frame F3 corresponds to the analysis condition setting sheet for "Analysis 3."

[0082] When multiple analysis target regions are set, it is preferable to display each region setting frame in a different color. Furthermore, when displaying each region setting frame in a different color, it is preferable to display the color (background color) of the corresponding analysis condition setting sheet DS (or its tab) in the same color. For example, if the first region setting frame F1 is displayed in red, the second region setting frame F2 is displayed in blue, and the third region setting frame F3 is displayed in yellow, the analysis condition setting sheet for "Analysis 1" is displayed in red, the analysis condition setting sheet for "Analysis 2" is displayed in blue, and the analysis condition setting sheet for "Analysis 3" is displayed in yellow. This clarifies the correspondence between the region setting frames and the analysis target sheets, improving convenience when setting analysis conditions.

[0083] As shown in Fig. 7, the analysis condition setting dialog D is provided with a button (close button) DB3 for instructing to close the dialog, and a button (execute button) DB4 for instructing to execute the analysis. Clicking the close button DB3 closes the analysis condition setting dialog D (disappears from the screen). The closed analysis condition setting dialog D can be displayed on the screen again by clicking the shape and size analysis button B21 again. Clicking the execute button DB4 instructs to execute the analysis.

[0084] (b) Image acquisition unit The image acquisition unit 31F acquires an image to be analyzed. The image acquisition unit 31F acquires, from the auxiliary storage device 33, an effective atomic number image of the image range accepted by the analysis condition acceptance unit 31E as the image to be analyzed.

[0085] (c) Image analysis section The image analysis unit 31G analyzes the image designated as the analysis target, and extracts a region (corresponding tissue region) containing the component of the effective atomic number designated as the analysis target from the region designated as the analysis target (analysis target region). The image range to be analyzed and the effective atomic number to be analyzed are set for each analysis target region, so that a corresponding tissue region is extracted for each analysis target region.

[0086] The extraction of the relevant tissue region is performed by extracting pixels containing a component of the specified effective atomic number from the region to be analyzed of each image. For example, if an effective atomic number of 2.00 is specified as the analysis target for the first analysis region, pixels containing an effective atomic number of 2.00 as a component are extracted, and the relevant tissue region is extracted. In this embodiment, the relevant tissue region is an example of the second region.

[0087] (d) Analysis result processing section Based on the analysis results from the image analysis unit 31G, the analysis result processing unit 31H identifies the shape of the region (corresponding tissue region) containing the component of the effective atomic number designated as the analysis target, and measures its size. When multiple images are designated as the analysis target (when an image range including multiple images is designated), the analysis result processing unit 31H identifies the shape of the corresponding tissue region as a three-dimensional shape and generates a three-dimensional image of it. The three-dimensional image is generated based on information about the pixels extracted as the corresponding tissue region.

[0088] The size is calculated based on the image resolution (pixel / mm). If the shape of the tissue region is identified as a three-dimensional shape, the analysis result processing unit 31H calculates the volume of the region. If the shape of the tissue region is identified as a plane (if there is only one image to be analyzed), the analysis result processing unit 31H calculates the area of ​​the region.

[0089] (e) Output control section The output control unit 31D outputs the analysis results to the display device 35. The output control unit 31D outputs information on the shape and size of the region extracted as the relevant tissue region in a predetermined format.

[0090] FIG. 10 is a diagram showing an example of a screen display of the analysis results.

[0091] As shown in FIG. 10, the analysis results are displayed in the image display area V1. In the image display area V1, analysis result display frames V11 to V13 are displayed according to the number of analysis target areas that have been set. FIG. 10 shows an example in which three analysis target areas have been set. The first analysis result display frame V11 displays the analysis results for the first analysis target area (analysis 1). The second analysis result display frame V12 displays the analysis results for the second analysis target area (analysis 2). The third analysis result display frame V13 displays the analysis results for the third analysis target area (analysis 3).

[0092] Within each frame, three-dimensional coordinates are displayed, and three-dimensional images Im1 to Im3 of the tissue region extracted from the corresponding analysis target region are also displayed. Information on the measured size is also displayed. The three-dimensional images Im1 to Im3 displayed within each frame can be individually enlarged, reduced, rotated, etc., in response to instructions from the user.

[0093] [Analysis processing behavior] FIG. 11 is a flowchart showing the operation procedure when performing a process for analyzing the shape and size of a specific tissue.

[0094] First, an effective atomic number image is displayed (step S1). As shown in Fig. 6, the effective atomic number image is displayed in an image display area V1.

[0095] Next, it is determined whether or not there is a request to perform analysis (step S2). A request to perform analysis is made by clicking the shape and size analysis button B21. The processor 31 determines whether or not there is a click on the shape and size analysis button B21, and determines whether or not there is a request to perform analysis.

[0096] When the Shape and Size Analysis button B21 is clicked and a request to perform analysis is accepted, analysis conditions are set (step S3). The processor 31 displays an analysis condition setting dialog D on the screen to accept the setting of analysis conditions (see FIG. 7). The user specifies the image range, the effective atomic number, and whether to enable or disable analysis in the analysis condition setting dialog D displayed on the screen. When setting analysis target regions in multiple locations, an analysis condition setting sheet DS is additionally displayed. For sheets for which analysis is enabled (analysis condition setting sheets for which the check box C11 is checked), a region setting frame is displayed on the image of the corresponding image range (see FIGS. 8 and 9). The user sets the analysis target region by adjusting the position, size, and shape (aspect ratio) of the region setting frame displayed on the effective atomic number image.

[0097] After completing the setting of the analysis conditions, the user instructs the execution of the analysis by clicking the execute button DB4 displayed in the analysis condition setting dialog D. The processor 31 determines whether or not the execute button DB4 has been clicked, and determines whether or not an instruction to execute the analysis has been given (step S4).

[0098] When an instruction to execute analysis is given, an effective atomic number image to be analyzed is acquired (step S5). The effective atomic number image to be analyzed is an effective atomic number image of an image range designated by the user.

[0099] The acquired effective atomic number image is subjected to image analysis under specified conditions (step S6). That is, from the specified region (analysis target region), a region (corresponding tissue region) containing the specified effective atomic number component is extracted. Then, based on the extraction result, the shape of the corresponding tissue region is identified and its size is measured.

[0100] After the analysis is completed, the analysis results are output to the display device 35 (step S7). The analysis results are displayed for each region to be analyzed, and a three-dimensional image of the extracted tissue region is displayed, as shown in Fig. 10. Information on the measured size is also displayed.

[0101] As described above, this embodiment can identify the shape and size of tissues containing a component with a specified effective atomic number and display them on the screen. This allows, for example, the shape and size of stones, etc., to be determined for each component. For example, ureteral stones are known to contain struvite, uric acid, cystine, calcium oxalate, calcium phosphate, and other components as their main components. Their respective effective atomic numbers are known to be 9.72 for struvite, 6.92 for uric acid, 11.07 for cystine, 13.52 for calcium oxalate, and 15.92 for calcium phosphate. Therefore, by specifying the effective atomic number of a desired component, its presence or absence can be determined, and if tissue containing that component is present, its shape and size can be determined. For example, if a uric acid stone is suspected, specifying 9.62 as the effective atomic number and performing analysis can determine its presence or absence, and, if present, its shape and size. Thus, this embodiment allows the shape and size of stones, whose treatment and prevention methods vary depending on the component, to be identified for each component. This improves the accuracy of treatment and preventive diagnosis.

[0102] [Variations] [Display image] (a) Display image type In the above embodiment, an effective atomic number image is output to the display device 35, and the analysis target region is set on the effective atomic number image displayed on the screen, but the image output to the display device 35 is not limited to this. For example, a normal CT image may be output to the display device 35, and the analysis target region may be set on the normal CT image displayed on the screen.

[0103] (b) Display of 3D images In the above embodiment, a two-dimensional tomographic image is displayed on the screen and the setting of the area to be analyzed is accepted, but a three-dimensional image may be generated from the two-dimensional tomographic image obtained by photography (scanning), and the generated three-dimensional image may be displayed on the screen and the setting of the area to be analyzed may be accepted. Since the generation of three-dimensional images is a well-known technique, detailed description thereof will be omitted.

[0104] FIG. 12 is a diagram showing an example of a screen display when an analysis target region is set on a three-dimensional image.

[0105] As shown in FIG. 12, a three-dimensional image Zeff_3D generated from the effective atomic number image is displayed in the image display area V1, and the setting of the analysis target area is accepted.

[0106] The region to be analyzed is set, for example, by displaying a cylinder C along the body axis direction and adjusting the position (position in a plane perpendicular to the body axis direction), size (size of cross section), and shape (shape of cross section) of the cylinder C. The region enclosed by the cylinder C is set as the region to be analyzed. The position and length of the cylinder C in the body axis direction are set in the image range. The image range may be set in the analysis condition setting dialog D, or may be set on the screen. When set on the screen, this is done by adjusting the position and length (height) of the cylinder C in the body axis direction.

[0107] [Analysis condition settings] (a) How to set the effective atomic number In the above embodiment, as a method for setting the effective atomic number to be analyzed, a text box C31 is provided in the effective atomic number setting field C3 of the analysis condition setting dialog D, and the user directly inputs the effective atomic number to the text box C31. The method for setting the effective atomic number to be analyzed is not limited to this. For example, multiple effective atomic numbers may be registered in advance and recalled as needed for setting (so-called presets). Specifically, multiple effective atomic numbers may be registered in advance as selection candidates, and presented to the user at the time of setting, allowing the user to select one. When selecting, it is preferable to display information on the corresponding components in association with the effective atomic number. For example, the effective atomic number and the components corresponding to that effective atomic number are displayed side by side. Furthermore, it is preferable to classify and register stones into multiple categories. For example, since the main components differ depending on the type (e.g., ureteral stones, kidney stones, bladder stones, gallbladder stones), even for the same stone, it is preferable to classify and register stones by type. Furthermore, if stones are classified and registered, it is preferable to allow selection by category. Furthermore, it is preferable that the user can add, change, delete, etc. the registration at will.

[0108] Fig. 13 is a diagram showing an example of an analysis condition setting screen (analysis condition setting dialog) when setting an effective atomic number using a preset, and Fig. 14 is a diagram showing an example of a screen (effective atomic number setting dialog) when setting an effective atomic number using a preset.

[0109] As shown in Figure 13, when setting the effective atomic number using a preset, a Set button C32 is provided in the analysis condition setting dialog D. The Set button C32 is a button that calls up the effective atomic number setting screen. The Set button C32 is provided in the field C3 for setting the effective atomic number. When the Set button C32 is clicked, the effective atomic number setting dialog ZD pops up and is displayed.

[0110] As shown in FIG. 14, the effective atomic number setting dialogue ZD has a field ZD1 for selecting an effective atomic number (effective atomic number selection field).

[0111] The effective atomic number selection field ZD1 is provided with a field ZD11 for selecting a main category and a field ZD12 for selecting an effective atomic number. The main category selection field ZD11 displays a list of selectable main categories. The effective atomic number selection field ZD12 displays a list of selectable effective atomic numbers for the main category selected in the main category selection field ZD11. The effective atomic numbers are displayed together with information on the corresponding components. More specifically, the components and their effective atomic numbers are displayed side by side. The main categories are classified, for example, according to disease names, etc. Figure 14 shows an example where stones are classified by type. Selectable effective atomic numbers are registered for each main category. For example, Figure 14 shows an example where "ureteral stones" is selected as the main category. This example shows a case where "Struvite: 9.72," "Uric acid: 6.92," "Cystine: 11.07," "Calcium oxalate: 13.52," and "Calcium phosphate: 15.95" are registered as selectable effective atomic numbers for the main classification "Ureteral stone." After selecting the main classification, the user selects the effective atomic number to be analyzed from the effective atomic numbers listed in effective atomic number selection field ZD12. The background color of the selected main classification and effective atomic number changes (for example, it is inverted).

[0112] The effective atomic number setting dialog ZD is provided with an OK button ZDB1, a cancel button ZDB2, a new registration button ZDB3, and an edit button ZDB4.

[0113] The OK button ZDB1 is a button that instructs the user to reflect (apply) the settings. When the OK button ZDB1 is clicked, the selected effective atomic number is reflected in the analysis condition settings. Specifically, the selected effective atomic number is automatically entered into the text box C31 in the field C3 for setting the effective atomic number in the analysis condition setting dialog D. When the OK button ZDB1 is clicked, the effective atomic number setting dialog ZD is cleared from the screen. To change the selection, click the setting button C32 again in the analysis condition setting dialog D.

[0114] The Cancel button ZDB2 is a button that instructs to cancel the setting operation of the effective atomic number by preset. When the Cancel button ZDB2 is clicked, the process is interrupted and the Effective Atomic Number Setting Dialog ZD is removed from the screen.

[0115] The New Registration button ZDB3 is a button that instructs the execution of a new registration. When the New Registration button ZDB3 is clicked, a specified registration screen is displayed, allowing the registration of an effective atomic number. The registration process includes the process of adding a main category and the process of adding a new effective atomic number to an already registered main category. When adding a main category, a name (category name) for the newly added main category is assigned, and the effective atomic number that will be selectable in that main category and the name of the component that corresponds to that effective atomic number are registered. When adding a new effective atomic number to an already registered main category, a main category is selected, and the effective atomic number to be added and the name of the component that corresponds to that effective atomic number are registered.

[0116] The edit button ZDB4 is a button that instructs editing of a registered effective atomic number. When the edit button ZDB4 is clicked, a specified edit screen is displayed, allowing editing of the effective atomic number. Editing processes include changing the name of the main classification, deleting the main classification, deleting a registered effective atomic number, correcting a registered effective atomic number, and correcting the name of a component associated with a registered effective atomic number.

[0117] By using the preset function in this way, the setting operation of the analysis conditions can be made easier, and convenience can be improved.

[0118] (b) Setting the effective atomic number with a range In the above embodiment, the effective atomic number to be analyzed is specified precisely, but it may be set with a range. For example, with regard to stones, the criteria for determining the effective atomic number value that constitutes a stone may differ depending on the facility. By setting a range for the effective atomic number value that can be set, the range of analysis targets can be expanded.

[0119] FIG. 15 is a diagram showing an example of an analysis condition setting screen (analysis condition setting dialogue D) when setting the effective atomic number with a certain range.

[0120] As shown in FIG. 15, in the analysis condition setting dialogue D of this example, a sheet for setting analysis conditions (analysis condition setting sheet DS) is provided with a field C4 for setting the range of effective atomic numbers.

[0121] In this example, the range is specified by specifying the negative and positive ranges based on the effective atomic number set in field C3 for setting the effective atomic number. For this reason, in the analysis condition setting dialog D of this example, field C4 for setting the range of the effective atomic number is provided with a text box C41 for inputting the negative range and a text box C42 for inputting the positive range.

[0122] In the text box C41 for inputting the minus range, a numerical value of the range to be set on the minus side is input, based on the value of the effective atomic number set in the field C3 for setting the effective atomic number.

[0123] In the text box C42 for inputting the range on the positive side, a numerical value of the range to be set on the positive side is input based on the effective atomic number set in the field C3 for setting the effective atomic number.

[0124] In the example shown in FIG. 15, "2.00" is specified as the reference effective atomic number, and "0.3" (-0.3) is specified as the negative range and "0.5" (+0.5) is specified as the positive range. That is, this example shows a case where analysis is performed in the range of -0.3 to +0.5 with 2.00 as the reference. In this case, the range of 1.70 to 2.50 is set as the effective atomic number to be analyzed. Therefore, when an instruction to perform analysis is given, analysis is performed with effective atomic numbers in the range of 1.70 to 2.50. That is, pixels containing components with effective atomic numbers in the range of 1.70 to 2.50 are extracted, and their shape and size are analyzed.

[0125] FIG. 16 is a diagram showing another example of the setting screen for analysis conditions when setting the effective atomic number with a certain range.

[0126] Figure 16 shows an example of setting the reference effective atomic number using a preset. Setting the effective atomic number using a preset is as described above.

[0127] In this example, the range of effective atomic numbers to be analyzed is specified by specifying the range on the minus side and the plus side in column C4 for setting the range of effective atomic numbers for the effective atomic numbers specified in the preset.

[0128] Alternatively, the range of effective atomic numbers to be analyzed may be set by directly inputting it. In this case, for example, a field for setting the range of effective atomic numbers is provided in the analysis condition setting sheet DS, and text boxes for inputting the start and end points of the range are provided in the field.

[0129] [Result Output] In the above embodiment, the shape and size of the tissue extracted by the analysis process are output as the analysis results, but it is also possible to output only one of the analysis results. For example, it is also possible to output only the shape analysis result. In this case, the size measurement can be omitted.

[0130] In the above embodiment, the three-dimensional shape of the extracted tissue is identified as a result of the shape analysis, and a three-dimensional image of the extracted tissue is generated and output. However, the result may be output in the form of a two-dimensional image. In this case, for example, two-dimensional images of the tissue region extracted from each image within the image range specified as the analysis target are individually displayed.

[0131] Furthermore, in the above embodiment, the shape analysis results are displayed independently, but they may also be displayed superimposed on the original 3D image of the analysis (a 3D image generated from a 2D tomographic image obtained by photography).

[0132] FIG. 17 is a diagram showing an example of a case where the analysis result is output by being superimposed on the three-dimensional image that is the source of the analysis.

[0133] 17, the original three-dimensional image Zeff_3D is displayed in the image display area V1, and three-dimensional images Im1 to Im3 of the tissue regions of interest extracted from each analysis target region are displayed superimposed on the three-dimensional image Zeff_3D. The three-dimensional images Im1 to Im3 of the tissue regions of interest are displayed in the same position and size as the original three-dimensional image Zeff_3D.

[0134] In this way, by outputting the analysis results superimposed on the original 3D image, it becomes easier to grasp the position and size.

[0135] In the above example, the analysis results are superimposed on the original 3D image and output. However, other configurations are also possible, for example, to generate a new 3D image of a specific organ or other part from a 2D tomographic image obtained by photography, and then superimpose and display the analysis results on the 3D image. Alternatively, for example, a 3D image of a region designated as the region to be analyzed may be generated, and then superimposed and displayed on the 3D image. It is preferable to employ multiple display formats so that the user can select any display format. For example, it is preferable to be able to freely switch between displaying the results individually and displaying them superimposed on the 3D image.

[0136] Furthermore, in the above example, only the analysis results of the shape are output, but if the size is measured, it is preferable to also display information on the measurement results.

[0137] FIG. 18 is a diagram showing an example of a case where the size measurement result is also displayed when the analysis result is output superimposed on the original three-dimensional image.

[0138] As shown in Fig. 18, the size measurement results are displayed near the three-dimensional images Im1 to Im3 of the tissue region in question. Alternatively, an area for displaying the size measurement results may be provided on the screen, and the size measurement results may be displayed in that area.

[0139] In this way, by displaying the size measurement results in addition to the shape analysis results, the shape and size of the target tissue can be easily confirmed.

[0140] [X-ray CT device] In the above embodiment, the present invention has been described as being applied to a PCCT device, but the application of the present invention is not limited to this. The present invention can be applied to any X-ray CT device that can measure effective atomic number (an X-ray CT device that can reconstruct an effective atomic number image from detection data obtained by imaging). For example, the present invention can be applied to any X-ray CT device (e.g., a spectral CT device) that has the function of reconstructing a CT image that allows material decomposition by detecting X-rays that have passed through a subject at two or more energy levels, since it can acquire an effective atomic number image.

[0141] [others] In the above embodiment, the console is provided with the functions of the image processing device, but the image processing device may be configured as an independent device separate from the console.

[0142] The processing unit that provides the functions of an image processing device can be configured with various types of processors. These include general-purpose processors such as CPUs and GPUs (Graphic Processing Units), as well as programmable logic devices (PLDs) such as FPGAs (Field Programmable Gate Arrays), whose circuit configuration can be changed after manufacturing, and dedicated electrical circuits such as ASICs (Application Specific Integrated Circuits), which are processors with circuit configurations specifically designed to perform specific processes. A single processing unit may be configured with one of the various types of processors, or with two or more processors of the same or different types. For example, a single processing unit may be configured with multiple FPGAs or a combination of a CPU and an FPGA. Alternatively, multiple processing units may be configured with a single processor. A first example of multiple processing units configured with a single processor is a configuration in which a single processor is configured with a combination of one or more CPUs and software, and this processor functions as multiple processing units, as typified by computers used as clients, servers, etc. Secondly, there is a form using a processor that realizes the functions of an entire system including multiple processing units on a single IC (Integrated Circuit) chip, as typified by a System on Chip (SoC), etc. In this way, various processing units are configured as a hardware structure using one or more of the above-mentioned various processors. [Explanation of symbols]

[0143] 1. PCCT device 10...Scanner gantry 10A…Opening 11...X-ray tube device 12...X-ray detection device 13...Data acquisition system 14...Rotating frame 20...Bed 21...Tabletop 30...Console 31...Processor 31A...Data acquisition section 31B...Image processing unit 31C...Recording control section 31D...Output control section 31E...Analysis condition reception section 31F…Image acquisition unit 31G...Image analysis section 31H...Analysis result processing section 32…Main memory 33…Auxiliary storage device 34...Input device 35…Display device 36...Input / output interface B11...Image forward button B12...Back button B21...Analysis button C...Cylinder C1: Column for enabling or disabling analysis C11...Checkbox C2: Column for setting the image range C21...Text box C22...Text box C3: Column for setting the effective atomic number C31...Text box C32...Settings button C4: Field for setting the range of effective atomic numbers C41...Text box C42…Text box D...Analysis condition setting dialog DB1…Add button DB2…Delete button DB3…button DB4...Execute button DS...Analysis condition setting sheet F1: First area setting frame F2: Second area setting frame F3: Third area setting frame Im1: 3D image of the tissue area Im2: 3D image of the tissue area Im3: 3D image of the tissue area P...Subject PT…Tab S: Area to be analyzed V1…Image display area V11: First analysis result display window V12: Second analysis result display window V13: Third analysis result display frame V2...Menu display area ZD...Effective atomic number setting dialog ZD1...Effective atomic number selection field ZD11: Field to select main classification ZD12...Field for selecting effective atomic number ZDB1...OK button ZDB2…Cancel button ZDB3…New registration button ZDB4...Edit button Zeff...effective atomic number image Zeff_1...Effective atomic number image Zeff_2...Effective atomic number image Zeff_3D...3D image S1 to S7: Operational procedures for analyzing the shape and size of a specific tissue

Claims

1. An image processing device that processes an image obtained by an X-ray computed tomography device capable of measuring effective atomic number, a processor; The processor: displaying at least one of the images obtained by the X-ray computed tomography apparatus on a display unit; Accepting a setting of a first area on the image displayed on the display unit; Accepts the setting of the effective atomic number to be analyzed, extracting pixels in the first region that include a component of the effective atomic number, and extracting a second region in the first region that includes a component of the effective atomic number; Identifying the shape of the second region; The shape of the second region is displayed on the display unit. Image processing device.

2. The processor: measuring the size of the second region; The shape and size of the second region are displayed on the display unit. The image processing device according to claim 1 .

3. The processor: Accepting a setting of the range of effective atomic numbers to be analyzed; 3. The image processing device according to claim 1 or 2.

4. The processor: accepting a setting of the effective atomic number value used as a reference and a range based on the value, and accepting a setting of the range of the effective atomic number to be analyzed; The image processing device according to claim 3 .

5. The processor: displaying the effective atomic number registered in advance on the display unit as the effective atomic number corresponding to a specific component; accepting a selection from the effective atomic numbers displayed on the display unit and accepting setting of the effective atomic number to be analyzed; 3. The image processing device according to claim 1 or 2.

6. the processor displays information about the component corresponding to the effective atomic number on the display unit in association with the effective atomic number. The image processing device according to claim 5 .

7. the processor accepts registration of the effective atomic number to be displayed on the display unit; The image processing device according to claim 5 .

8. The processor: Accepting a plurality of settings of the first region; Accepting a setting of the effective atomic number to be analyzed for each of the first regions; extracting the second region for each of the first regions; specifying a shape of the second region for each of the first regions; a shape of the second area is displayed on the display unit for each of the first areas; 3. The image processing device according to claim 1 or 2.

9. The processor: measuring the size of the second region for each of the first regions; the shape and size of the second area are displayed on the display unit for each of the first areas. The image processing device according to claim 8 .

10. The processor: Accepting a setting of a range of images to be analyzed from among a plurality of images obtained by the X-ray computed tomography apparatus; extracting the second region individually from the image within a set range; Identifying a three-dimensional shape of the second region; displaying the three-dimensional shape of the second region on the display unit; 3. The image processing device according to claim 1 or 2.

11. The processor: measuring the volume of the second region to measure the size of the second region; displaying the three-dimensional shape and volume of the second region on the display unit; The image processing device according to claim 10.

12. The processor: a three-dimensional image generated from a plurality of images obtained by the X-ray computed tomography apparatus is displayed on the display unit; accepting setting of the first region on the three-dimensional image displayed on the display unit; The image processing device according to claim 10.

13. the processor displays the three-dimensional shape of the second region on a three-dimensional image generated from a plurality of images obtained by the X-ray computed tomography apparatus.

3. The image processing device according to claim 1 or 2.

14. the X-ray computed tomography apparatus is an X-ray computed tomography apparatus capable of photon counting computed tomography; 3. The image processing device according to claim 1 or 2.

15. The image obtained by the X-ray computed tomography apparatus is an effective atomic number image. The image processing device according to claim 14.

16. An image processing method for processing an image obtained by an X-ray computed tomography apparatus capable of measuring effective atomic number, comprising: displaying at least one of the images obtained by the X-ray computed tomography apparatus on a display unit; Accepting a setting of a first area on the image displayed on the display unit; Accepts the setting of the effective atomic number to be analyzed, extracting pixels in the first region that include a component of the effective atomic number, and extracting a second region in the first region that includes a component of the effective atomic number; Identifying the shape of the second region; The shape of the second region is displayed on the display unit. Image processing methods.

17. An image processing program for processing an image obtained by an X-ray computed tomography apparatus capable of measuring effective atomic number, a function of displaying at least one of a plurality of images obtained by the X-ray computed tomography apparatus on a display unit; a function of accepting setting of a first area on the image displayed on the display unit; A function to accept the setting of the effective atomic number to be analyzed, A function of extracting pixels including the component of the effective atomic number within the first region and extracting a second region including the component of the effective atomic number within the first region; A function of specifying the shape of the second region; a function of displaying the shape of the second region on the display unit; An image processing program that enables a computer to achieve this.

Images