Medical information processing device, method, and program

Abstract

To grasp a utilization degree of X-ray energy related to a PCCT scan.SOLUTION: A medical image processing apparatus includes an acquisition unit, a reconstitution unit, a generation unit, and a storage unit. The acquisition unit acquires count data on a plurality of energy bins collected in a PCCT scan for a subject. The reconstitution unit reconstitutes a PCCT image on the basis of the count data on a first energy bin of the plurality of energy bins. The generation unit generates utilization information for evaluating a utilization degree of X-ray energy emitted in the PCCT scan on the reconstitution of the PCCT image on the basis of the first energy bin used in the reconstitution of the PCCT image or the second energy bin that is not used for the reconstitution of the PCCT image. The storage unit stores the utilization information in a memory in association with the PCCT image and / or related information of the PCCT image.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The embodiments disclosed in this specification and the drawings relate to a medical information processing apparatus, method, and program.

Background Art

[0002] In photon counting CT (PCCT: Photon Counting Computed Tomography), it is possible to generate various images by collecting data divided into a plurality of energy bins. For example, when generating an image from only the count data of a specific energy bin or when generating an image from the count data of energy bins other than a specific energy bin, only a part of the energy of the X-rays irradiated to the subject and detected by the X-ray detector contributes to imaging.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0004] One of the problems to be solved by the embodiments disclosed in this specification and the drawings is to grasp the utilization degree of the irradiated X-ray energy related to PCCT scanning. However, the problems to be solved by the embodiments disclosed in this specification and the drawings are not limited to the above problems. The problems corresponding to the respective effects of each configuration shown in the embodiments described later can also be regarded as other problems.

Means for Solving the Problem

[0005] The medical information processing apparatus according to the embodiment includes an acquisition unit, a reconstruction unit, a generation unit, and a storage unit. The acquisition unit acquires count data regarding a plurality of energy bins collected in a PCCT scan of a subject. The reconstruction unit reconstructs one or more PCCT images based on the count data regarding the first energy bin among the plurality of energy bins. The generation unit generates utilization information for evaluating the degree of utilization of the energy of the X-rays irradiated in the PCCT scan for the reconstruction of the one or more PCCT images, based on the first energy bin used for the reconstruction of the one or more PCCT images or a second energy bin that is not used for the reconstruction of the one or more PCCT images among the plurality of energy bins other than the first energy bin. The storage unit stores the utilization information in association with the one or more PCCT images and / or related information of the one or more PCCT images in a storage device.

Brief Description of the Drawings

[0006]

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[0007] Hereinafter, with reference to the drawings, a medical information processing apparatus, method, and program according to the present embodiment will be described in detail.

[0008] The X-ray computed tomography apparatus according to the present embodiment includes various types such as third-generation CT and fourth-generation CT, and any type can be applied to the present embodiment. Here, the third-generation CT is of the Rotate / Rotate-Type in which the X-ray tube and the X-ray detector rotate around the subject integrally. The fourth-generation CT is of the Stationary / Rotate-Type in which a large number of X-ray detection elements arrayed in a ring shape are fixed and only the X-ray tube rotates around the subject. In addition, the X-ray computed tomography apparatus according to the present embodiment can be applied to a single-tube type in which one pair of an X-ray tube and an X-ray detector is mounted on a rotating ring, and a multi-tube type in which a plurality of pairs of an X-ray tube and an X-ray detector are mounted on a rotating ring. However, in the following description, it is assumed to be a single-tube type.

[0009] The X-ray computed tomography apparatus according to the present embodiment is assumed to be a photon counting CT apparatus that executes photon counting CT (PCCT: Photon Counting Computed Tomography).

[0010] FIG. 1 is a diagram showing the configuration of the X-ray computed tomography apparatus 1 according to the present embodiment. As shown in FIG. 1, the X-ray computed tomography apparatus 1 includes a gantry 10, a couch 30, and a console 40. In FIG. 1, for convenience of explanation, the gantry 10 is illustrated at a plurality of locations, but the number of gantries 10 installed in the X-ray computed tomography apparatus 1 may be one or more. The gantry 10 is a scanning device having a configuration for performing a PCCT scan on the subject P. The couch 30 is a transport device for placing the subject P to be subjected to X-ray CT imaging and positioning the subject P. The console 40 is a computer for controlling the gantry 10. For example, the gantry 10 and the couch 30 are installed in a CT examination room, and the console 40 is installed in a control room adjacent to the CT examination room. The gantry 10, the couch 30, and the console 40 are connected to each other by wire or wirelessly so as to be communicable. Note that the console 40 does not necessarily have to be installed in the control room. For example, the console 40 may be installed in the same room as the gantry 10 and the couch 30. Further, the console 40 may be incorporated into the gantry 10. The console 40 is an example of a medical information processing device.

[0011] As shown in FIG. 1, the gantry 10 includes an X-ray tube 11, an X-ray detector 12, a rotating frame 13, an X-ray high voltage device 14, a control device 15, a wedge 16, a collimator 17, and a data acquisition circuit (DAS: Data Acquisition System) 18.

[0012] The X-ray tube 11 generates X-rays. Specifically, the X-ray tube 11 includes a cathode that generates thermoelectrons, an anode that receives the thermoelectrons flying from the cathode and generates X-rays, and a vacuum tube that holds the cathode and the anode. The X-ray tube 11 is connected to the X-ray high-voltage device 14 via a high-voltage cable. A tube voltage is applied between the cathode and the anode by the X-ray high-voltage device 14. When the tube voltage is applied, thermoelectrons fly from the cathode toward the anode. When thermoelectrons fly from the cathode toward the anode, a tube current flows. By applying a high voltage from the X-ray high-voltage device 14 and supplying a filament current, thermoelectrons fly from the cathode (filament) toward the anode (target), and when the thermoelectrons collide with the anode, X-rays are generated. For example, the X-ray tube 11 includes a rotating-anode type X-ray tube that generates X-rays by irradiating a rotating anode with thermoelectrons.

[0013] The X-ray detector 12 detects the X-rays generated from the X-ray tube 11 and passing through the subject P, and outputs an electrical signal corresponding to the energy of the detected X-rays to the data acquisition circuit 18. The X-ray detector 12 has a structure in which a plurality of X-ray detector element arrays in which a plurality of X-ray detector elements are arranged in the channel direction are arranged in a plurality in the slice direction (column direction). The X-ray detector 12 is, for example, an indirect conversion type detector having a grid, a scintillator array, and an optical sensor array. The scintillator array has a plurality of scintillators. Each scintillator generates a plurality of fluorescent photons corresponding to the energy of the incident X-ray photons. The grid is disposed on the X-ray incident surface side of the scintillator array and has an X-ray shielding plate that absorbs scattered X-rays. Note that the grid may also be called a collimator (one-dimensional collimator or two-dimensional collimator). The optical sensor array converts the plurality of fluorescent photons from the scintillator into an electrical signal having a pulse height value corresponding to the energy of the incident X-ray photons. As the optical sensor, for example, a photodiode is used.

[0014] The X-ray detector 12 may be a direct conversion type detector. As the direct conversion type X-ray detector 12, for example, a type including a semiconductor diode having electrodes attached to both ends of a semiconductor is applicable. X-ray photons incident on the semiconductor are converted into electron-hole pairs. The number of electron-hole pairs generated by the incidence of one X-ray photon depends on the energy of the incident X-ray photon. The electrons and holes are attracted to each other by a pair of electrodes formed at both ends of the semiconductor. The pair of electrodes generates an electrical signal having a pulse height value corresponding to the charge of the electron-hole pairs. One electrical signal has a pulse height value corresponding to the energy of the incident X-ray photon.

[0015] The rotating frame 13 is an annular frame that rotatably supports the X-ray tube 11 and the X-ray detector 12 around the rotation axis (Z-axis). Specifically, the rotating frame 13 supports the X-ray tube 11 and the X-ray detector 12 so as to face each other. The rotating frame 13 is rotatably supported around the rotation axis by a fixed frame (not shown). By rotating the rotating frame 13 around the rotation axis by the control device 15, the X-ray tube 11 and the X-ray detector 12 are rotated around the rotation axis. The rotating frame 13 rotates around the rotation axis at a constant angular velocity receiving power from the drive mechanism of the control device 15. An image field of view (FOV) is set in the opening 19 of the rotating frame 13.

[0016] In this embodiment, the rotation axis of the rotating frame 13 in the non-tilted state or the longitudinal direction of the top plate 33 of the bed 30 is defined as the Z-axis direction, the axial direction orthogonal to the Z-axis direction and horizontal with respect to the floor surface is defined as the X-axis direction, and the axial direction orthogonal to the Z-axis direction and perpendicular to the floor surface is defined as the Y-axis direction.

[0017] The X-ray high voltage device 14 includes a high voltage generator and an X-ray control device. The high voltage generator has electric circuits such as a transformer and a rectifier, and generates a high voltage applied to the X-ray tube 11 and a filament current supplied to the X-ray tube 11. The X-ray control device controls the output voltage according to the X-rays irradiated by the X-ray tube 11. The high voltage generator may be of a transformer type or an inverter type. The X-ray high voltage device 14 may be provided on the rotating frame 13 within the gantry 10, or may be provided on a fixed frame (not shown) within the gantry 10.

[0018] The wedge 16 adjusts the dose of X-rays irradiated to the subject P. Specifically, the wedge 16 attenuates the X-rays so that the dose of X-rays irradiated from the X-ray tube 11 to the subject P has a predetermined distribution. For example, as the wedge 16, a metal plate such as aluminum, such as a wedge filter or a bow-tie filter, is used.

[0019] The collimator 17 limits the irradiation range of the X-rays that have passed through the wedge 16. The collimator 17 slidably supports a plurality of lead plates that shield the X-rays, and adjusts the form of the slit formed by the plurality of lead plates. Note that the collimator 17 may also be referred to as an X-ray aperture.

[0020] The data acquisition circuit 18 collects the count data of the X-rays detected by the X-ray detector 12 for each energy bin. As an example, the data acquisition circuit 18 includes a preamplifier, a waveform shaping circuit, a pulse height discrimination circuit, and a counting circuit. The preamplifier amplifies an electrical signal having a pulse height value corresponding to the energy of the X-ray photons detected by the X-ray detector 12 at a predetermined magnification. The waveform shaping circuit shapes the waveform of the electrical signal output by the preamplifier. The pulse height discrimination circuit applies an energy threshold value corresponding to each of a plurality of energy bins to the electrical signal output by the waveform shaping circuit, and outputs an electrical pulse signal corresponding to the energy bin to which the electrical signal belongs. The counting circuit generates count data representing the number of counts of X-ray photons for each energy bin by counting the electrical pulse signals output from the pulse height discrimination circuit for each energy bin in units of a view period. The data acquisition circuit 18 is realized by, for example, an application specific integrated circuit (ASIC). The digital data is transmitted to the console 40 via a non-contact data transmission device or the like.

[0021] The control device 15 controls the X-ray high-voltage device 14 and the data acquisition circuit 18 to execute a PCCT scan in accordance with the control by the processing circuit 45 of the console 40. The control device 15 includes a processing circuit having a CPU (Central Processing Unit) or an MPU (Micro Processing Unit), etc., and a drive mechanism such as a motor and an actuator. The processing circuit has, as hardware resources, a processor such as a CPU and memories such as a ROM (Read Only Memory) and a RAM (Random Access Memory). Further, the control device 15 may be realized by an ASIC or a field programmable gate array (FPGA). Further, the control device 15 may be realized by another complex programmable logic device (CPLD) or a simple programmable logic device (SPLD). The control device 15 has a function of being attached to the console 40 or the gantry 10, receiving an input signal from an input interface 43 described later, and controlling the operations of the gantry 10 and the bed 30. For example, the control device 15 performs control to rotate the rotary frame 13 upon receiving an input signal, control to tilt the gantry 10, and control to operate the bed 30 and the top plate 33. Note that the control to tilt the gantry 10 is realized by the control device 15 rotating the rotary frame 13 about an axis parallel to the X-axis direction based on the tilt angle information input by an input interface attached to the gantry 10. Note that the control device 15 may be provided on the gantry 10 or may be provided on the console 40.

[0022] The bed 30 includes a base 31, a support frame 32, a top plate 33, and a bed driving device 34. The base 31 is installed on the floor surface. The base 31 is a housing that supports the support frame 32 so as to be movable in a direction perpendicular to the floor surface (Y-axis direction). The support frame 32 is a frame provided above the base 31. The support frame 32 supports the top plate 33 so as to be slidable along the rotation axis (Z-axis). The top plate 33 is a flexible plate on which the subject P is placed.

[0023] The bed driving device 34 is housed inside the housing of the bed 30. The bed driving device 34 is a motor or an actuator that generates power for moving the support frame 32 and the top plate 33 on which the subject P is placed. The bed driving device 34 operates according to the control by the console 40 or the like.

[0024] The console 40 has a memory 41, a display 42, an input interface 43, a communication interface 44, and a processing circuit 45. Data communication among the memory 41, the display 42, the input interface 43, the communication interface 44, and the processing circuit 45 is performed via a bus (BUS). Although the console 40 is described as being separate from the gantry 10, the gantry 10 may include the console 40 or a part of each component of the console 40.

[0025] The memory 41 is a storage device such as a HDD (Hard Disk Drive), SSD (Solid State Drive), or integrated circuit memory device that stores various information. The memory 41 stores, for example, count data and PCCT image data. In addition to HDDs, SSDs, etc., the memory 41 may be a portable storage medium such as a CD (Compact Disc), DVD (Digital Versatile Disc), or flash memory. The memory 41 may also be a drive device that reads and writes various information to and from semiconductor memory elements such as flash memory and RAM (Random Access Memory). Further, the storage area of the memory 41 may be within the X-ray computed tomography apparatus 1 or within an external storage device connected via a network. The memory 41 stores a database described later.

[0026] The display 42 displays various information. For example, the display 42 outputs a PCCT image generated by the processing circuit 45, a GUI (Graphical User Interface) for receiving various operations from the operator, etc. Various arbitrary displays can be used as the display 42 as appropriate. For example, as the display 42, a liquid crystal display (LCD), a CRT (Cathode Ray Tube) display, an organic EL display (OELD), or a plasma display can be used. Further, the display 42 may be provided on the gantry 10. Also, the display 42 may be a desktop type, or may be configured as a tablet terminal or the like capable of wireless communication with the console 40 main body.

[0027] The input interface 43 receives various input operations from the operator, converts the received input operations into electrical signals, and outputs them to the processing circuit 45. As the input interface 43, for example, a mouse, keyboard, trackball, switch, button, joystick, touch pad, touch panel display, etc. can be appropriately used. In this embodiment, the input interface 43 is not limited to those equipped with physical operation components such as a mouse, keyboard, trackball, switch, button, joystick, touch pad, and touch panel display. For example, a processing circuit for electrical signals that receives an electrical signal corresponding to an input operation from an external input device provided separately from the apparatus and outputs this electrical signal to the processing circuit 45 is also included in the example of the input interface 43. Further, the input interface 43 may be provided on the gantry 10. Also, the input interface 43 may be configured by a tablet terminal or the like that can communicate wirelessly with the console 40 main body.

[0028] The communication interface 44 includes a network interface card (NIC) or the like for communicating various data via a network with external devices such as a workstation, PACS (Picture Archiving and Communication Systems), RIS (Radiology Information System), HIS (Hospital Information System), etc.

[0029] The processing circuit 45 controls the operation of the entire X-ray computed tomography apparatus 1 according to the electrical signals of the input operations output from the input interface 43. The processing circuit 45 has, as hardware resources, a processor such as a CPU and a memory such as a ROM and a RAM. The processing circuit 45 realizes various functions by a processor that executes a program developed in the memory. The various functions are not limited to being realized by a single processing circuit. It is also possible to configure a processing circuit by combining a plurality of independent processors, and each processor executes a program to realize various functions.

[0030] As shown in FIG. 1, the processing circuit 45 realizes a scan control function 51, an acquisition function 52, a reconstruction function 53, a utilization information generation function 54, a comment input function 55, a storage function 56, and a display control function 57.

[0031] In the scan control function 51, the processing circuit 45 controls the gantry 10 to perform a PCCT scan on the subject P. Under the control of the processing circuit 45, the PCCT scan is performed by the gantry 10. When the PCCT scan is executed, the data collection circuit 18 collects count data for each of a plurality of energy bins for each view.

[0032] In the acquisition function 52, the processing circuit 45 acquires various information. As an example, the processing circuit 45 may acquire, from the data collection circuit 18, count data regarding a plurality of energy bins collected by a PCCT scan of the subject P. When the count data is stored in the memory 41, the processing circuit 45 may acquire the count data regarding the plurality of energy bins from the memory 41.

[0033] In the reconstruction function 53, the processing circuit 45 reconstructs one or more PCCT images based on the count data regarding the first energy bin among the plurality of energy bins. The PCCT image means an image based on the count data collected by the PCCT scan.

[0034] The PCCT image according to the present embodiment may be either a two-dimensional image regarding one slice or slab or a three-dimensional image regarding one volume. The two-dimensional image means image data composed of a plurality of pixels arranged in a two-dimensional space, and the three-dimensional image means image data composed of a plurality of voxels arranged in a three-dimensional space. Hereinafter, a three-dimensional image is assumed as the PCCT image.

[0035] In the utilization information generation function 54, the processing circuit 45 generates information (hereinafter referred to as energy utilization information) for evaluating the degree of utilization of the energy of the X-rays irradiated in the PCCT scan for the reconstruction of one or more PCCT images, based on the first energy bin or a plurality of energy bins used for the reconstruction of one or more PCCT images, and the second energy bin that is not used for the reconstruction of the one or more PCCT images among the plurality of energy bins other than the first energy bin. The first energy bin means an energy bin that contributes to imaging, and the second energy bin means an energy bin that does not contribute to imaging. Specifically, the energy utilization information includes the identifier and / or energy range of the first energy bin or the second energy bin, the energy utilization efficiency representing the ratio of the energy range of the first energy bin to the energy ranges of the plurality of energy bins, and / or the energy non-utilization efficiency representing the ratio of the energy range of the second energy bin to the energy ranges of the plurality of energy bins.

[0036] In the comment input function 55, the processing circuit 45 inputs a comment on the energy utilization information generated by the utilization information generation function 54. As an example, the processing circuit 45 may input a comment limited to the case where the degree of utilization represented by the energy utilization information generated by the utilization information generation function 54 does not meet a predetermined condition. The said condition is defined as reaching a level sufficient to evaluate that the energy utilization information is appropriate. The said condition will be called the appropriate condition. The processing circuit 45 inputs a comment in a free input format or a selection format from fixed phrases.

[0037] In the storage function 56, the processing circuit 45 associates the energy utilization information generated by the utilization information generation function 54 with one or more PCCT images and / or related information of the one or more PCCT images, and stores them in the storage device. The related information is, for example, DICOM files of one or more PCCT images, performed scan information regarding a PCCT scan for collecting count data used for the one or more PCCT images, and / or order information for the PCCT scan. The storage device may be the memory 41 equipped in the X-ray computed tomography apparatus 1, or may be a storage device in an information system such as a PACS, HIS, or RIS connected via the communication interface 44. Hereinafter, the storage device where the energy utilization information is stored is referred to as a data storage device. Unless otherwise specified, the data storage device is assumed to be the memory 41 equipped in the X-ray computed tomography apparatus 1.

[0038] In the display control function 57, the processing circuit 45 displays various information on the display 42. As an example, the processing circuit 45 displays one or more PCCT images reconstructed by the reconstruction function 53, energy utilization information generated by the utilization information generation function 54, and the like. At this time, the processing circuit 45 may display the energy utilization information together with one or more PCCT images. Note that the processing circuit 45 converts the PCCT image into a visualization image and displays it on the display 42. As the conversion process to the visualization image, a pixel value projection method such as MIP (Maximum Intensity Projection), multi-planar reconstruction (MPR), volume rendering, a conversion process from a three-dimensional image to a two-dimensional image such as surface rendering is used.

[0039] Hereinafter, the details of the X-ray computed tomography apparatus 1 will be described. In the following description, the first energy bin is also referred to as the used bin, and the second energy bin is also referred to as the unused bin.

[0040] FIG. 2 is a diagram showing an example of a processing procedure of a PCCT examination by the X-ray computed tomography apparatus 1. As shown in FIG. 2, first, the processing circuit 45 acquires image generation conditions and bin setting information by the acquisition function 52 (step S1). The image generation conditions and bin setting information are set before the PCCT scan is performed. For example, the image generation conditions and bin setting information are set as one content of protocol information by the RIS. The protocol information is information indicating the processing procedure of the PCCT examination and the setting conditions of each process, etc., and includes, in addition to the image generation conditions and bin setting information, scan conditions of the PCCT scan, etc. The RIS sets the protocol information based on the order information of the PCCT examination. In step S1, the processing circuit 45 acquires the protocol information from the RIS. Thereby, the processing circuit 45 acquires the image generation conditions and bin setting information. Note that the image generation conditions and bin setting information may be set by another in-hospital information system, the X-ray computed tomography apparatus 1, or the like. The acquired image generation conditions and bin setting information are stored in the memory 41.

[0041] The image generation conditions are condition items related to the reconstruction of the PCCT image, and specifically include the examination site of the subject P and the image generation purpose. As the examination site, any body part of the subject P such as the head, chest, abdomen, legs, brain, heart, lungs, liver, etc. can be specified. As the image generation purpose, an energy integration image, a blood vessel enhancement or suppression image, a fat enhancement or suppression image, a calcium enhancement or suppression image, an iodine enhancement or suppression image, a uric acid enhancement or suppression image, a contrast enhancement image, an electron density image, an effective atomic number image, a virtual monochromatic image, a basis material image and / or a K-edge image, etc., any type of PCCT image that can be generated from the count data may be specified. The type of PCCT image may be specified together with the used bin and X-ray energy. For example, it may be specified like an energy integration image using the second and third energy bins, a virtual monochromatic image of 70 keV.

[0042] The bin setting information means information regarding the settings of the energy bins, and as its items, it has the number of energy bins, the energy range, the energy width, and the used / unused discrimination information of each energy bin. The used / unused discrimination information is a label indicating whether each energy bin is used for the reconstruction of the PCCT image according to the purpose of image generation. Specifically, as the used / unused discrimination information indicating an energy bin used for the reconstruction of the PCCT image, the label "used" is used, and as the used / unused discrimination information indicating an energy bin not used for the reconstruction of the PCCT image, the label "not used" is used.

[0043] Figure 3 is a diagram showing an example of the bin setting information. Figure 3 illustrates the relationship between the energy spectrum of the X-rays irradiated from the X-ray tube 11 and the energy bins. The vertical axis of the energy spectrum in Figure 3 represents the count, and the horizontal axis represents the X-ray energy.

[0044] In Figure 3, assume that the tube voltage value is "140 kVp" and the purpose of image generation is "energy-integrated image using the 1st to 3rd energy bins". Also, assume the following for the bin setting information. In the following description, the energy bin may also be simply referred to as a bin. Also, the Xth energy bin may also be simply referred to as bin X.

[0045] Number of energy bins = 4 Bin 1: Energy range = 20 - 50 keV, Energy width = 30 keV, Used / unused discrimination information = "used" Bin 2: Energy range = 50 - 80 keV, Energy width = 30 keV, Used / unused discrimination information = "used" Bin 3: Energy range = 80 - 110 keV, Energy width = 30 keV, Used / unused discrimination information = "used" Bin 4: Energy range = 110 - 140 keV, Energy width = 30 keV, Used / unused discrimination information = "not used"

[0046] When step S1 is performed, the processing circuit 45 executes a PCCT scan on the subject P by the scan control function 51 (step S2). In step S2, the processing circuit 45 controls the gantry 10 according to separately set scan conditions to execute a PCCT scan on the subject P. Specifically, first, the number and values of the energy thresholds of the data acquisition circuit 18 are set according to the number and energy range of the energy bins included in the bin setting information. The control device 15 controls the X-ray high voltage device 14 to irradiate X-rays from the X-ray tube 11 while rotating the rotary frame 13 at high speed. The X-ray detector 12 detects the X-rays irradiated from the X-ray tube 11 and transmitted through the subject P. The data acquisition circuit 18 collects count data for each of a plurality of energy bins for each view via the X-ray detector 12. The count data is transmitted to the console 40. The processing circuit 45 acquires the count data by the acquisition function 52.

[0047] When step S2 is performed, the processing circuit 45 reconstructs a PCCT image based on the count data acquired in step S2 by the reconstruction function 53 (step S3). In step S3, specifically, the processing circuit 45 reads out the image generation purpose and bin setting information stored in the memory 41. Next, the processing circuit 45 reads out the use / non-use discrimination information in the bin setting information and selects the count data of the used bins from the count data acquired in step S2. Next, the processing circuit 45 reconstructs a PCCT image corresponding to the image generation purpose based on the selected count data. In this embodiment, it is assumed that one PCCT image is reconstructed.

[0048] When step S3 is performed, the processing circuit 45 generates energy utilization information by the utilization information generation function 54 (step S4). In step S4, the processing circuit 45 generates energy utilization information based on the bin setting information acquired in step S1. Specifically, the processing circuit 45 extracts information regarding the used bins and / or unused bins, such as the numbers of the used bins and / or unused bins, the energy ranges and / or the energy widths, from the bin setting information. Then, the processing circuit 45 generates used / unused bin information representing the identifiers and / or energy ranges of the used bins and / or unused bins, and the energy utilization efficiency representing the ratio of the energy width of the used bins to the energy width of all bins. Hereinafter, the generation process of the used / unused bin information and the energy utilization efficiency will be described.

[0049] Used / unused bin information: Since the identifiers, energy ranges and / or energy widths of the used bins and / or unused bins are recorded in the bin setting information, the processing circuit 45 can extract the identifiers, energy ranges and / or energy widths of the used bins and / or unused bins from the bin setting information. Note that when the energy width is not included in the bin setting information, the processing circuit 45 may calculate the energy width from the energy range. Also, when the energy range is defined by the lower limit value and the upper limit value of the energy range, the processing circuit 45 may set the range between the upper limit value and the lower limit value as the energy range, and calculate the energy width by subtracting the lower limit value from the upper limit value. By comparing the identifiers and / or energy ranges of all bins with the identifiers and / or energy ranges of the used bins and / or unused bins, a user such as a doctor or a technician can estimate the degree to which the irradiation X-ray energy is utilized for the reconstruction of the PCCT image. Therefore, it can be said that the identifiers and / or energy ranges of the used bins and / or unused bins are a kind of energy utilization information.

[0050] Energy utilization efficiency: The processing circuit 45 calculates the energy utilization efficiency based on the bin setting information. Specifically, the processing circuit 45 first identifies the energy width of all bins and the energy width of the used bins from the bin setting information, and divides the energy width of the used bins by the energy width of all bins to calculate the energy utilization efficiency, which is the ratio of the energy width of the used bins to the energy width of all bins. Since the energy utilization efficiency represents the ratio of the energy range of the X-rays contributing to imaging to the energy range of the irradiated X-rays, the user can estimate the degree to which the energy of the irradiated X-rays is utilized for the reconstruction of the PCCT image by checking the energy utilization efficiency. Therefore, it can be said that the energy utilization efficiency is a type of energy utilization information.

[0051] When step S4 is performed, the processing circuit 45 stores the energy utilization information generated in step S4 in the data storage device by the storage function 56 (step S5). In step S5, the processing circuit 45 stores the energy utilization information in the data storage device in association with the PCCT image reconstructed in step S3.

[0052] Figure 4 is a conceptual diagram of the storage of the PCCT image 62 and the energy utilization information 63 in the data storage device 61. Assume that the bin setting information in the example of Figure 4 is the same as the bin setting information in Figure 3. As shown in Figure 4, the energy utilization information 63 includes the numbers of all bins, the numbers of used bins, the numbers of unused bins, and the energy utilization efficiency. Specifically, all bins are bins 1 to 4, the used bins are bins 1 to 3, and the unused bin is bin 4. Since the energy range of all bins is 20 to 140 keV, the energy width of all bins is 140 keV - 20 keV = 120 keV. Since the energy range of the used bins is 20 to 110 keV, the energy width of the used bins is 110 keV - 20 keV = 90 keV. Therefore, the energy utilization efficiency, which is the ratio of the energy width of the used bins to the energy width of all bins, is calculated to be 90 keV / 120 keV = 75%.

[0053] When step S5 is performed, the processing circuit 45 determines whether or not the proper conditions are satisfied by the comment input function 55 (step S6). The proper conditions may be set for the used bin or the used bin, or may be set for the energy utilization efficiency. As the proper conditions for the used bin or the used bin, it may be set that the energy bin on the highest energy side among the plurality of energy bins is being used, that an energy bin with energy equal to or higher than a threshold value is being used, and the like. As the proper condition for the energy bin utilization efficiency, it may be set that the energy utilization efficiency exceeds a threshold value. The proper conditions are not limited to the above and can be arbitrarily set.

[0054] If it is determined in step S6 that the proper criteria are satisfied (step S6: YES), the processing circuit 45 causes the display control function 57 to display the PCCT image reconfigured in step S3, the energy utilization information generated in step S4, and the determination result of step S6 on the display 42 (step S7).

[0055] FIG. 5 is a diagram showing an example of a display screen I1 of the PCCT image I11, the energy utilization information I12, and the determination result I13 according to step S7. The bin setting information in FIG. 5 assumes the following.

[0056] Number of energy bins = 4 Bin 1: Energy range = 20 to 50 keV, energy width = 30 keV, use / non - use discrimination information = "Used" Bin 2: Energy range = 50 to 80 keV, energy width = 30 keV, use / non - use discrimination information = "Used" Bin 3: Energy range = 80 to 110 keV, energy width = 30 keV, use / non - use discrimination information = "Used" Bin 4: Energy range = 110 to 140 keV, energy width = 30 keV, use / non - use discrimination information = "Used"

[0057] As described above, all of the bins 1 to 4 are used bins, there are no unused bins, and the energy utilization efficiency is 100%. Also, assume that the appropriate conditions are two, namely the first condition "the energy utilization efficiency exceeds 80%" and the second condition "the energy bin on the highest energy side is being used". In the bin setting information of FIG. 5, the energy utilization efficiency is 100% and exceeds 80%, so the first condition is satisfied. The used bins are bins 1 to 4, and bin 4, which is the energy bin on the highest energy side, is being used, so the second condition is also satisfied.

[0058] As shown in FIG. 5, on the display screen I1, the PCCT image I11 reconstructed in step S3, the energy utilization information I12 generated in step S4, and the determination result I13 of step S6 are arranged and displayed. As the energy utilization information I12, texts such as "All bins: 1 to 4", "Used bins: 1 to 4", "Unused bins: -", "Energy utilization efficiency: 100%" are displayed. As the determination result I13, texts indicating that the first condition such as "Energy utilization efficiency > 80%" is satisfied as the determination result of the first condition, and texts indicating that the second condition such as "Highest energy use = YES" is satisfied as the determination result of the second condition may be displayed.

[0059] When step S7 is performed, the PCCT inspection shown in FIG. 2 ends.

[0060] On the other hand, when it is determined in step S6 that the appropriate standard is not met (step S6: NO), the processing circuit 45 causes the display control function 57 to display the PCCT image reconstructed in step S3, the energy utilization information generated in step S4, and the determination result of step S6 (step S8).

[0061] FIG. 6 is a diagram showing an example of a display screen I2 of a PCCT image I21, energy utilization information I22, and a determination result I23 according to step S8. The bin setting information in the example of FIG. 6 assumes the same bin setting information as in FIG. 3. Also, the appropriate conditions are the same as in the example of FIG. 5, and there are two conditions: the first condition is that "the energy utilization efficiency exceeds 80%", and the second condition is that "the energy bin on the highest energy side is being used". In the example of FIG. 6, since the energy utilization efficiency is 75% and does not exceed 80%, the first condition is not satisfied. Since the used bins are bins 1 to 3 and the energy bin 4, which is the energy bin on the highest energy side, is not being used, the second condition is also not satisfied.

[0062] As shown in FIG. 6, on the display screen I2, the PCCT image I21 reconstructed in step S3, the energy utilization information I22 generated in step S4, and the determination result I23 of step S6 are arranged and displayed. As the energy utilization information I22, texts such as "All bins: 1 to 4", "Used bins: 1 to 3", "Unused bin: 4", "Energy utilization efficiency: 75%" are displayed. As the determination result I23, texts indicating that the first condition is not satisfied, such as "Energy utilization efficiency < 80%", are displayed as the determination result of the first condition, and texts indicating that the second condition is not satisfied, such as "Highest energy use = NO", are displayed as the determination result of the second condition.

[0063] As shown in FIG. 6, when the appropriate conditions are not satisfied, a comment input field I24 may be further displayed on the display screen I2. In the comment input field I24, in step S9, comments regarding the circumstances, reasons, justifications, etc. for not satisfying the appropriate conditions are input. The input format of comments to the comment input field I24 is assumed to be a free input format (free text format).

[0064] When step S8 is performed, the processing circuit 45 inputs a comment by the comment input function 55 (step S9). If the appropriate conditions are not satisfied, the processing circuit 45 prompts the user to input a comment regarding the circumstances, reasons, excuses, etc. for not satisfying the appropriate conditions. For example, the processing circuit 45 may display a message window such as "Please input a comment" superimposed on the display screen I2 shown in FIG. 6, or may output a voice such as "Please input a comment" via a speaker, or may emphasize the comment input field I24 with a visual effect such as blinking. Note that the processing circuit 45 may simply display the comment input field I24 to prompt the user to input a comment.

[0065] In step S9, the user freely inputs a comment such as "The high energy side is not subject to inspection" into the comment input field I24 via the input interface 43. The text of the input comment is immediately displayed within the comment input field I24.

[0066] FIG. 7 is a diagram showing another example of the display screen I3 of the PCCT image I21, energy utilization information I22, and determination result I23 related to step S8. The case of FIG. 7 is the same as the case of FIG. 6. On the display screen I3, the PCCT image I31 reconstructed in step S3, the energy utilization information I32 generated in step S4, and the determination result I33 of step S6 are arranged and displayed.

[0067] As shown in FIG. 7, a selection-type comment input field I34 is displayed on the display screen I3. In the comment input field I34, GUI (Graphical User Interface) buttons I35 to I38 with stereotyped texts representing typical comment contents are displayed. When the GUI buttons I35 to I38 are pressed, the texts associated with the GUI buttons I35 to I38 are input. As an example, when the GUI button I35 with the stereotyped text of "human factor" is pressed, a comment indicating that the appropriate conditions were not met due to human factors is input. As another example, when the GUI button I36 with the stereotyped text of "noise removal purpose" is pressed, a comment indicating that the appropriate conditions were not met due to setting the energy range dominated by noise to the unused bin is input. As another example, when the GUI button I37 with the stereotyped text of "excluded" is pressed, a comment indicating that the appropriate conditions were not met due to setting the tissue component outside the inspection target to the unused bin in the energy range dominated by it is input. As another example, when the GUI button I38 with the stereotyped text of "others" is pressed, a free-form comment input field may be superimposed and displayed on the display screen I3. By inputting in a selection format, it is possible to save the trouble of inputting comments and standardize the comments for similar factors.

[0068] When step S9 is performed, the processing circuit 45 saves the comment input in step S9 in the data storage device by the storage function 56 (step S10). In step S10, the processing circuit 45 saves the comment in association with, for example, the PCCT image reconstructed in step S3 or the energy appropriateness information generated in step S4.

[0069] FIG. 8 is a conceptual diagram of the storage of comment 74 in the data storage device 71. As shown in FIG. 8, in addition to the PCCT image 72 and the energy utilization information 73, the data storage device 71 further stores a comment 74. The PCCT image 72, the energy utilization information 73, and the comment 74 may be stored in association with each other. By storing the comment 74 in this way, it becomes possible to record in the record the degree of utilization of the irradiation X-ray energy in the PCCT examination, specifically, the views of the examiner at the time of the PCCT examination regarding the fact that the energy utilization information does not meet the appropriate conditions. Also, by associating the comment 74 with the PCCT image 72 or the energy utilization information 73, it becomes possible to easily read out the comment 74.

[0070] The storage mode of the comment 74 is not limited to the above only. As an example, the comment 74 may be associated with only one of the PCCT image 72 and the energy utilization information 73. As another example, the comment 74 may be incorporated into the comment column of the PCCT image 72, or the comment 74 may be incorporated as the content of the energy utilization information 73.

[0071] As described above, the PCCT examination shown in FIG. 2 is completed.

[0072] Note that the processing procedure of the PCCT examination shown in FIG. 2 is an example, and the present embodiment is not limited thereto. As an example, the determination of the appropriate conditions (S6) and the subsequent processing (S7 to S10) are not essential, and steps S6 to S10 may be omitted. The determination of the appropriate conditions (S6) is not essential, and the input (S9) and storage (S10) of the comment may be performed unconditionally. The generation (S4) and storage (S5) of the energy utilization information may be performed between steps S1 and S2, or between steps S2 and S3. The storage (S5) of the energy utilization information may be performed after the display (S7 and / or S8).

[0073] The above embodiment is an example, and is not limited to only this embodiment. As long as the gist of the invention is not deviated from, addition, deletion, and / or change of any element is possible.

[0074] (Modification Example 1) In the above embodiment, the processing circuit 45 associates energy utilization information with the PCCT image. However, the energy utilization information may be indirectly associated with the PCCT image. The processing circuit 45 according to Modification Example 1 associates energy utilization information with the related information of the PCCT image. Hereinafter, Modification Example 1 will be specifically described. In the following description, components having substantially the same functions as those in the above embodiment are denoted by the same reference numerals, and redundant description will be given only when necessary.

[0075] The related information is information directly or indirectly associated with the PCCT image. Specifically, as the related information, it is possible to use the DICOM file of the PCCT image, the performed scan information regarding the PCCT scan for collecting the count data used for the reconstruction of the PCCT image, and / or the order information for the PCCT scan.

[0076] The DICOM file has a study file for each DICOM study. The DICOM file is stored in a data storage device. The data storage device may be the memory 41 of the X-ray computed tomography apparatus 1, or a storage device provided in a PACS, RIS, HIS, or other in-hospital information system. The processing circuit 45 stores the energy utilization information in the study file related to the PCCT scan of the DICOM study. Since the PCCT image is stored in the DICOM file, it is possible to associate the energy utilization information with the PCCT image by storing the energy utilization information in the study file.

[0077] The executed scan information includes various types of information related to the PCCT examination, such as radiation dose information, billing information, and material usage information for the executed PCCT scan. The radiation dose information is managed as an RDSR (Radiation Dose Structured Report) object in the DICOM standard. As an example, the processing circuit 45 according to Modification 1 uses energy utilization information as one content of the radiation dose information in the executed scan information. Specifically, when the energy utilization information is generated, the processing circuit 45 transmits the energy utilization information to the RIS according to the Modality Performed Procedure Step (MPPS). MPPS means a communication procedure defined in the DICOM standard. By transmitting the energy utilization information according to MPPS, the RIS stores the energy utilization information in its storage device as the executed scan information in the DICOM specification, specifically, as an RDSR object. Thereby, it becomes possible to store the energy utilization information in association with the executed scan information. Note that the processing circuit 45 may store the energy utilization information in the memory 41 in association with the executed scan information.

[0078] The order information means the examination order of the executed PCCT scan. The order information is issued by the HIS and transmitted to the RIS as an example. Based on the order information, the RIS sets the image generation conditions, bin setting information, and scan conditions. The image generation conditions, bin setting information, and scan conditions are transmitted from the RIS to the X-ray computed tomography apparatus 1. When the energy utilization information is generated, the processing circuit 45 transmits the energy utilization information to the RIS according to MPPS. The RIS stores the energy utilization information in the data storage device in association with the order information. Thereby, it becomes possible to store the energy utilization information in association with the order information. Note that the processing circuit 45 may store the energy utilization information in the memory 41 in association with the order information.

[0079] (Modification 2) In the above-described embodiment, it was assumed that the medical information processing apparatus 40 is a console provided in the X-ray computed tomography apparatus 1. However, the present embodiment is not limited to this. The medical information processing apparatus 40 according to Modification 2 may be a computer separate from the X-ray computed tomography apparatus 1 such as a diagnostic reading apparatus, an image inspection apparatus, or a workstation. In this case, the medical information processing apparatus 40 does not necessarily need to have the scan control function 51. The processing circuit 45 according to Modification 2 may acquire count data from an X-ray computed tomography apparatus or an in-hospital information system such as a PACS, and perform reconstruction of a PCCT image, generation of energy utilization information, and storage of energy utilization information in the same manner as in the above-described embodiment.

[0080] According to Modification 2, in the medical information processing apparatus 40 independent of the X-ray computed tomography apparatus 1, it is possible to perform reconstruction of a PCCT image, generation of energy utilization information, and storage of energy utilization information in the same manner as in the above-described embodiment. Thereby, it is possible to grasp the degree of utilization of X-ray energy related to PCCT scanning.

[0081] (Modification 3) The processing circuit 45 according to the above-described embodiment calculates, as the energy utilization efficiency, the ratio of the energy width of the first energy bin (used bin) used for reconstruction of the PCCT image to the energy width of a plurality of energy bins (all bins). However, the definition of the energy utilization efficiency is not limited to the above only, and various modifications are possible. Which of the following energy utilization efficiencies is adopted can be arbitrarily selected by a user or the like via the input interface 43 or the like.

[0082] As an example, the processing circuit 45 according to Modification 3 may use the ratio of the number of used bins to the number of all bins as the energy utilization efficiency. As another example, the processing circuit 45 may calculate the ratio of the energy-weighted energy width of the used bins to the energy-weighted energy width of all bins as the energy utilization efficiency. Here, the energy-weighted energy width of all bins or used bins is calculated as the integrated value of the X-ray energy over the energy range to which all bins or used bins belong.

[0083] As another example, the processing circuit 45 may calculate the energy utilization efficiency in consideration of the X-ray spectrum of the irradiated X-rays or the X-ray spectrum of the detected X-rays. In other words, the processing circuit 45 may calculate the ratio of the energy-weighted energy width of the used bins to the energy-weighted energy width of all bins weighted by the count and energy of all bins as the energy utilization efficiency. The count and energy-weighted energy width of all bins or used bins are calculated as the integrated value of the X-ray spectrum related to the energy range to which all bins or used bins belong.

[0084] (Modification 4) In the above embodiment, the processing circuit 45 calculates the energy utilization efficiency for one PCCT image based on one piece of count data. However, the present embodiment is not limited thereto. The processing circuit 45 according to Modification 4 calculates the energy utilization efficiency for a plurality of PCCT images based on one piece of count data. In this case, as the energy utilization efficiency of the plurality of PCCT images, the processing circuit 45 calculates the ratio of the energy width of the first energy bin (used bin) used for the reconstruction of any one of the plurality of PCCT images to the energy widths of the plurality of energy bins (all bins). Hereinafter, Modification 4 will be specifically described. In the following description, components having substantially the same functions as those in the above embodiment are denoted by the same reference numerals, and redundant description will be given only when necessary. In addition, the energy utilization efficiency for one PCCT image is referred to as the single-image energy utilization efficiency, the energy utilization information for one PCCT image is referred to as the single-image energy utilization information, the energy utilization efficiency for a plurality of PCCT images is referred to as the image-group energy utilization efficiency, and the energy utilization efficiency for a plurality of PCCT images is referred to as the image-group energy utilization information.

[0085] As an example of a scenario for reconstructing a plurality of PCCT images based on one piece of count data, a scenario of reconstructing a plurality of PCCT images belonging to the same DICOM (Digital Imaging and Communication in Medicine) study is assumed.

[0086] As an example, the bin setting information according to Modification 4 is assumed to be as follows. Number of energy bins = 4 Bin 1: Energy range = 20 - 50 keV, energy width = 30 keV Bin 2: Energy range = 50 - 80 keV, energy width = 30 keV Bin 3: Energy range = 80 - 110 keV, energy width = 30 keV Bin 4: Energy range = 110 - 140 keV, energy width = 30 keV

[0087] In Modification 4, it is assumed that three PCCT images are reconstructed based on one piece of count data. The use / non-use discrimination information for each PCCT image is as follows. First PCCT image: Bin 1 = "Used", Bin 2 = "Used", Bin 3 = "Not used", Bin 4 = "Not used" Second PCCT image: Bin 1 = "Used", Bin 2 = "Not used", Bin 3 = "Not used", Bin 4 = "Not used" Third PCCT image: Bin 1 = "Not used", Bin 2 = "Used", Bin 3 = "Not used", Bin 4 = "Not used"

[0088] As described above, since the energy width of all bins is such that the energy range is 20 to 140 keV, it is 140 keV - 20 keV = 120 keV. And since the used bins for reconstructing any one of the three PCCT images are Bins 1 and 2, the energy width of the used bins is 30 keV + 30 keV = 60 keV. Therefore, the image group energy utilization efficiency, which is the ratio of the energy width of the used bins for reconstructing any one of the three PCCT images to the energy width of all bins, is calculated to be 60 keV / 120 keV = 50%.

[0089] The processing circuit 45 according to Modification 4 stores the image group energy utilization information in the data storage device in association with the plurality of PCCT images. The image group energy utilization information may be associated with each of the plurality of PCCT images, or may be associated with the association information of the plurality of PCCT images. As the association information, for example, it is possible to use a DICOM file in which the plurality of PCCT images are recorded.

[0090] FIG. 9 is a conceptual diagram of the storage of energy utilization information 85 of a plurality of PCCT images 83n in the data storage device 81. As shown in FIG. 9, three individual energy utilization information 84m (m is the subscript of the energy utilization information, m = 1, 2, or 3) are associated with each of the three PCCT images 83n (n is the subscript of the PCCT image, n = 1, 2, or 3). The energy utilization information 84m of the PCCT image 83n includes the single - energy utilization efficiency generated by the above - mentioned several methods. The image group energy utilization information 85 common to the three PCCT images 83n includes the image group energy utilization efficiency. The single - energy utilization efficiency 83m evaluates the degree of utilization of the energy of the irradiated X - rays for the corresponding PCCT image 83n, while the image group energy utilization efficiency can evaluate the degree of utilization of the energy of the irradiated X - rays for the entire one DICOM study.

[0091] As shown in FIG. 9, the three PCCT images 83n, the three individual energy utilization information 84m, and the image group energy utilization information 85 are recorded in the DICOM file 82. The DICOM file 82 is stored in the data storage device 81. The DICOM file 82 is a file that manages an image group associated with one PCCT examination. Specifically, it manages three PCCT images reconstructed based on one count data collected by a PCCT scan performed in one PCCT examination. By registering the energy utilization information 85 in the DICOM file 82, it is possible to associate the image group energy utilization information 85 with the three PCCT images 83n and the three individual energy utilization information 84m. Thereby, it becomes possible to manage the image group energy utilization information 85 across the three PCCT images 83n.

[0092] (Modification Example 5) As shown in FIG. 2 of the above embodiment, before performing the PCCT scan (S2), the processing circuit 45 acquires image generation conditions and bin setting information (S1). Therefore, before performing the PCCT scan, the processing circuit 45 can determine the presence or absence of unused bins based on the bin setting information. When there are unused bins, the processing circuit 45 according to Modification 5 may recommend using an X-ray attenuation filter that shields X-rays in the energy range to which the unused bins belong. The X-ray attenuation filter may form part of the wedge 16 or the collimator 17, or may be a filter separate from the wedge 16 and the collimator 17. Hereinafter, Modification 5 will be specifically described. In the following description, components having substantially the same functions as those in the above embodiment are denoted by the same reference numerals, and redundant description will be given only when necessary.

[0093] As an example, the bin setting information according to Modification 5 is assumed as follows. Number of energy bins = 4 Bin 1: Energy range = 20 - 50 keV, energy width = 30 keV, unused Bin 2: Energy range = 50 - 80 keV, energy width = 30 keV, unused Bin 3: Energy range = 80 - 110 keV, energy width = 30 keV, used Bin 4: Energy range = 110 - 140 keV, energy width = 30 keV, used

[0094] In this case, the processing circuit 45 recommends using an X-ray attenuation filter that shields X-ray energy with an upper limit value of 80 keV or less of the X-ray energy of the unused bins. The recommended method is not particularly limited. For example, a message recommending the X-ray attenuation filter may be displayed on the display 42, or a voice recommending the X-ray attenuation filter may be output via the speaker. The user who receives the recommendation determines whether the X-ray attenuation filter needs to be used, and if it is determined that the use is necessary, the use of the X-ray attenuation filter is set. This makes it possible to reduce the irradiation of the subject with X-rays of X-ray energy components that do not contribute to imaging.

[0095] (Modification Example 6) In the above embodiment, the processing circuit 45 calculates the energy utilization efficiency representing the ratio of the energy range of the first energy bin (used bin) to the energy ranges of a plurality of energy bins (all bins) as one piece of energy utilization information. However, the present embodiment is not limited to this. The processing circuit 45 according to Modification Example 6 calculates the energy non-utilization efficiency representing the ratio of the energy range of the second energy bin (unused bin) to the energy ranges of a plurality of energy bins (all bins) as one piece of energy utilization information. Hereinafter, Modification Example 6 will be specifically described. In the following description, components having substantially the same functions as those in the above embodiment are denoted by the same reference numerals, and redundant description will be given only when necessary.

[0096] The bin setting information according to Modification Example 6 is assumed to be the same as the bin setting information in the case of FIG. 3 as an example. That is, bins 1 to 3 are used bins, and bin 4 is an unused bin. In this case, since the energy width of all bins is an energy range of 20 to 140 keV, it is 140 keV - 20 keV = 120 keV, and the energy width of the unused bin is an energy range of 110 to 140 keV, so it is 140 keV - 110 keV = 30 keV. Therefore, the energy non-utilization efficiency, which is the ratio of the energy width of the unused bin to the energy width of all bins, is calculated to be 30 keV / 120 keV = 25%. That is, it means that 25% of the total energy does not contribute to imaging. The processing circuit 45 can use the energy non-utilization efficiency as energy utilization information instead of or together with the energy utilization efficiency. For example, the processing circuit 45 may associate and store the energy non-utilization efficiency with the PCCT image and / or related information, or may display it on the display 42.

[0097] (Modification Example 7) In the above-described embodiment, the energy utilization information is generated when the PCCT examination is performed. In this case, the processing circuit 45 extracts information regarding the first energy bin (used bin) and / or the second energy bin (unused bin) from the bin setting information set before the PCCT scan is performed. However, this embodiment is not limited to this. After the PCCT examination is completed, it is also assumed that a PCCT image is reconstructed according to new image generation conditions and bin setting information based on the collected count data. The processing circuit 45 according to Modification 7 may also generate energy utilization information for the PCCT image generated after the PCCT examination is completed. In this case, the processing circuit 45 may set information regarding the first energy bin (used bin) and / or the second energy bin (unused bin) after the PCCT scan is performed.

[0098] (Summary) As described above, the medical information processing apparatus 40 includes a processing circuit 45 that realizes an acquisition function 52, a reconstruction function 53, an utilization information generation function 54, and a storage function 56. The processing circuit 45 acquires count data regarding a plurality of energy bins collected in a PCCT scan of the subject P. The processing circuit 45 reconstructs one or more PCCT images based on the count data regarding the first energy bin among the plurality of energy bins. The processing circuit 45 generates energy utilization information for evaluating the degree of utilization of the energy of the X-rays irradiated in the PCCT scan for the reconstruction of one or more PCCT images, based on the first energy bin used for the reconstruction of one or more PCCT images or one or more second energy bins not used for the reconstruction of one or more PCCT images other than the first energy bin among the plurality of energy bins. The processing circuit 45 associates the energy utilization information with one or more PCCT images and / or related information of the one or more PCCT images and stores it in the data storage device.

[0099] According to the above configuration, energy utilization information can be generated as an index for evaluating the degree of utilization of irradiation X-ray energy related to the reconstruction of PCCT images. By having medical staff involved in PCCT examinations check the energy utilization information, it is possible to grasp the presence or absence and the degree of effective utilization of irradiation X-ray energy. Along with this, it can also be expected to give medical staff an incentive to increase the degree of utilization of irradiation X-ray energy or an incentive to suppress the generation of irradiation X-ray energy that does not contribute to imaging. Also, according to the above configuration, it is possible to associate the energy utilization information with the PCCT image and / or related information and store it over a long period. As a result, it becomes possible to read it from the data storage device and check / verify the energy utilization information at any time.

[0100] According to at least one of the embodiments described above, it is possible to grasp the degree of utilization of irradiation X-ray energy related to PCCT scanning.

[0101] The term "processor" used in the above description means, for example, a CPU, a GPU, or a circuit such as an Application Specific Integrated Circuit (ASIC), a Programmable Logic Device (for example, a Simple Programmable Logic Device (SPLD), a Complex Programmable Logic Device (CPLD), and a Field Programmable Gate Array (FPGA)). The processor realizes its function by reading and executing a program stored in a storage circuit. Instead of storing the program in the storage circuit, the program may be directly incorporated into the circuit of the processor. In this case, the processor realizes its function by reading and executing the program incorporated in the circuit. On the other hand, when the processor is, for example, an ASIC, instead of storing the program in the storage circuit, the function is directly incorporated as a logic circuit into the circuit of the processor. Note that each processor of the present embodiment is not limited to being configured as a single circuit for each processor, and a plurality of independent circuits may be combined to form one processor to realize its function. Further, a plurality of components in FIG. 1 may be integrated into one processor to realize its function.

[0102] Although several embodiments have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, changes, and combinations of the embodiments can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalent scope thereof.

Explanation of Reference Numerals

[0103] 1 X-ray computed tomography apparatus 10 Stand 11 X-ray tube 12 X-ray detector 13 Rotating frame 14 X-ray high voltage device 15 Control device 16 Wedge 17 Collimator 18 Data acquisition circuit (DAS) 19 Opening 30 Bed 31 Base 32 Support frame 33 Ceiling 34 Bed drive device 40 Console (medical information processing device) 41 Memory 42 Display 43 Input interface 44 Communication interface 45 Processing circuit 51 Scan control function 52 Acquisition function 53 Reconstruction function 54 Utilization information generation function 55 Comment input function 56 Saving function 57 Display control function

Claims

1. An acquisition unit that acquires count data regarding a plurality of energy bins collected in a PCCT scan of a subject; A reconstruction unit that reconstructs one or more PCCT images based on the count data regarding a first energy bin among the plurality of energy bins; A generation unit that generates utilization information for evaluating the degree of utilization of the energy of the X-rays irradiated in the PCCT scan for the reconstruction of the one or more PCCT images, based on the first energy bin used for the reconstruction of the one or more PCCT images or one or more second energy bins among the plurality of energy bins that are not used for the reconstruction of the one or more PCCT images; A storage unit that associates the utilization information with the one or more PCCT images and / or related information of the one or more PCCT images and stores it in a storage device; A medical information processing apparatus comprising the above.

2. The utilization information includes: An identifier and / or energy range of the first energy bin or the second energy bin; An energy utilization efficiency representing the ratio of the energy range of the first energy bin to the energy ranges of the plurality of energy bins, and / or An energy non-utilization efficiency representing the ratio of the energy range of the second energy bin to the energy ranges of the plurality of energy bins, The medical information processing apparatus according to Claim 1.

3. The generation unit calculates, as the energy utilization efficiency of the one PCCT image, the ratio of the energy width of the first energy bin used for the reconstruction of the one PCCT image to the energy widths of the plurality of energy bins. The medical information processing apparatus according to Claim 2.

4. The generation unit calculates, as the energy utilization efficiency of the plurality of P CCT images, the ratio of the energy width of the first energy bin used for reconstructing any one of the plurality of P CCT images to the energy width of the plurality of energy bins. The medical information processing apparatus according to claim 2.

5. The medical information processing apparatus further includes an input unit that inputs a comment on the utilization information. The storage unit stores the comment together with the utilization information in the storage device. The medical information processing apparatus according to claim 1.

6. The input unit inputs the comment when the utilization degree does not satisfy a predetermined condition. The medical information processing apparatus according to claim 5.

7. The input unit inputs the comment in a free input format or a selection format from fixed sentences. The medical information processing apparatus according to claim 5.

8. The medical information processing apparatus according to claim 1 further includes a display control unit that displays the utilization information on a display device.

9. The display control unit displays the utilization information together with the one or more P CCT images. The medical information processing apparatus according to claim 8.

10. The generation unit extracts information on the first energy bin and / or the second energy bin from bin setting information set before the P CCT scan is performed. The medical information processing apparatus according to claim 1.

11. The generation unit sets information on the first energy bin and / or the second energy bin after the P CCT scan is performed. The medical information processing apparatus according to claim 1.

12. The medical information processing apparatus according to claim 1, wherein the related information is a DICOM file of the one or more PCT images, executed scan information regarding the PCT scan, and / or order information for the PCT scan.

13. Obtain count data regarding a plurality of energy bins collected in a PCT scan of a subject, Reconstruct one or more PCT images based on the count data regarding a first energy bin among the plurality of energy bins, Generate utilization information for evaluating the degree of utilization of the energy of X-rays irradiated in the PCT scan for the reconstruction of the one or more PCT images, based on the first energy bin used for the reconstruction of the one or more PCT images or a second energy bin among the plurality of energy bins that has not been used for the reconstruction of the one or more PCT images other than the first energy bin, Associate the utilization information with the one or more PCT images and / or related information of the one or more PCT images, and store it in a storage device. A medical information processing method comprising the above.

14. Cause a computer to Have a function of obtaining count data regarding a plurality of energy bins collected in a PCT scan of a subject, Have a function of reconstructing one or more PCT images based on the count data regarding a first energy bin among the plurality of energy bins, Have a function of generating utilization information for evaluating the degree of utilization of the energy of X-rays irradiated in the PCT scan for the reconstruction of the one or more PCT images, based on the first energy bin used for the reconstruction of the one or more PCT images or a second energy bin among the plurality of energy bins that has not been used for the reconstruction of the one or more PCT images other than the first energy bin, A function of associating the utilization information with the one or more P CCT images and / or related information of the one or more P CCT images and storing the utilization information in a storage device; A medical information processing program for realizing the above.

Images