Simulator, control method of simulator, and simulation program

Abstract

To display an image for determining whether or not a desired pixel value is acquired in a part selected by an operator.SOLUTION: A simulator 40 includes: a prediction unit 46 for simulating a pixel value in a selected part when a contrast medium is injected according to a predetermined injection condition; a determination unit 47 for determining whether or not the pixel value is higher than an upper limit and determining whether or not the pixel value is lower than a lower limit on the basis of a result of the simulation by the prediction unit; and a display control unit 48 for displaying a first image 61A in a display unit 26 when the pixel value is higher than the upper limit, and displaying a second image 61B of a display mode different from that of the first image in the display unit when the pixel value is lower than the lower limit.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a simulator, a control method for a simulator, and a simulation program. [Background technology]

[0002] Patent Document 1 discloses a simulator including a prediction unit that predicts changes in pixel values ​​of each tissue over time and a display unit that displays a schematic predicted image of each tissue. The display unit is controlled by a display control unit to change the shading of each compartment according to changes in pixel values ​​over time. As an example, in an image of each tissue immediately after a contrast agent is injected into an upper limb vein, the upper limb vein is shown with its natural pixel value (dark gray). In addition, all blood vessels including the abdominal aorta and celiac artery are shown with their natural pixel value (dark gray). In an image of each tissue taken about 25 seconds after the start of injection, the abdominal aorta, celiac artery, internal jugular vein, etc. are shown in particular white, while the upper limb vein is shown in light gray. Furthermore, in an image of each tissue taken about 120 seconds after the start of injection, the entire tissue is shown in light gray compared to the image immediately after injection. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2016 / 084373 Summary of the Invention [Problem to be solved by the invention]

[0004] In the simulator described in Patent Document 1, the shading of the image of each tissue changes according to the change over time in the pixel value of each tissue. This allows the operator to visually recognize the change in the image of each tissue. However, the operator cannot determine from the image of each tissue whether the desired pixel value is obtained in the part selected as the imaging part. [Means for solving the problem]

[0005] In order to solve the above problem, a simulator as an example of the present invention includes a prediction unit that simulates a pixel value at a selected site when a contrast agent is injected according to specified injection conditions, a judgment unit that judges whether the pixel value is higher than an upper limit value and whether the pixel value is lower than a lower limit value based on a simulation result by the prediction unit, and a display control unit that displays a first image on a display unit when the pixel value is higher than the upper limit value, and displays a second image having a display mode different from that of the first image on the display unit when the pixel value is lower than the lower limit value.

[0006] In order to solve the above problem, a control method for a simulator as an example of the present invention simulates pixel values ​​at a selected site when a contrast agent is injected according to specified injection conditions, and based on the simulation results, determines whether the pixel value is higher than an upper limit value and determines whether the pixel value is lower than a lower limit value, and displays a first image when the pixel value is higher than the upper limit value, and displays a second image having a display manner different from that of the first image when the pixel value is lower than the lower limit value.

[0007] In order to solve the above problem, a simulation program as an example of the present invention causes a simulator computer to function as: a prediction unit that simulates pixel values ​​at a selected site when a contrast agent is injected according to specified injection conditions; a judgment unit that judges whether the pixel value is higher than an upper limit value and judges whether the pixel value is lower than a lower limit value based on a simulation result by the prediction unit; and a display control unit that displays a first image on a display unit when the pixel value is higher than the upper limit value and displays a second image having a display mode different from that of the first image on the display unit when the pixel value is lower than the lower limit value.

[0008] This allows the operator to determine whether or not a desired pixel value has been obtained in the selected region.

[0009] Further characteristics of the invention will become apparent from the following description of an embodiment thereof, given by way of example only with reference to the accompanying drawings, in which: [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram of an injection system and an imaging system. [Diagram 2] FIG. 2 is a schematic block diagram of a simulator. [Diagram 3] 13 is a confirmation screen displayed on the display unit. [Figure 4] 13 is a simulation screen in the case where pixel values ​​within a desired range are obtained. [Diagram 5] 13 is a simulation screen when the pixel value falls below the lower limit. [Figure 6] 13 is a simulation screen in which the pixel value exceeds the upper limit. [Figure 7] 13 is a flowchart showing a display of a determination result. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, exemplary embodiments for carrying out the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, and relative positions of components described in the following embodiments are arbitrary and can be changed according to the configuration of the device to which the present invention is applied or various conditions. Furthermore, unless otherwise specified, the scope of the present invention is not limited to the embodiments specifically described below.

[0012] Unless otherwise specified, the term contrast agent includes both the contrast agent alone and a drug solution containing a contrast agent plus other solvents and additives. In the following, unless otherwise specified, the term pixel value includes the CT value of a selected site to be imaged, the sum or average of the CT values ​​of pixels included in a region of interest (ROI), or the SD value (standard deviation value) of the region of interest. Furthermore, the pixel value includes a value obtained by subtracting a value in a tissue not imaged (for example, the CT value of an imaging site in a simple CT) from these values. The region of interest is set in advance, or the operator can select the region of interest.

[0013] [First embodiment] With reference to FIG. 1, which is a schematic diagram of the injection system 120 and the imaging system 130, a system including a simulator 40 (FIG. 2) that simulates pixel values ​​at a selected site will be described. For example, the simulator 40 is provided in one of the injection system 120 and the imaging system 130. Alternatively, the simulator 40 may be an external device separate from the injection system 120 and the imaging system 130. The external device may be connected to at least one of the injection system 120 and the imaging system 130 by wire or wirelessly. An example in which the injection system 120 includes the simulator 40 will be described below.

[0014] Injection system 120 includes injection head 20, which is an example of an injection device that injects a contrast agent according to an injection protocol, and touch panel 26, which is an example of a display unit. Injection head 20 injects medicinal liquids, such as physiological saline and various contrast agents, filled in a syringe into a subject. Injection system 120 also includes stand 22 that holds injection head 20, and console 23 that is connected to injection head 20 by wire or wirelessly.

[0015] The console 23 functions as a control device for controlling the injection head 20, and also functions as a simulator 40 for predicting changes in pixel values ​​at a selected site over time. Alternatively, the injection system 120 may include a computer device that functions as the simulator 40, separate from the console 23. The computer device may be connected to the injection head 20 by wire or wireless. The console 23 also includes a touch panel 26 that functions as a display unit and an input unit, and can communicate with the injection head 20 and the imaging device 30 by wire or wireless. The touch panel 26 can display the injection protocol, the input state of the device, the setting state, the injection result, various information, and the like. The operator can also input the drug solution information, the injection protocol, the site information, the subject information, and the target value through the touch panel 26. The target value is the target pixel value and the target maintenance time, which is the maintenance time for maintaining the target pixel value. Alternatively, the injection system 120 may include a display as a display unit and an input device such as a keyboard or a numeric keypad as an input unit, instead of the touch panel 26.

[0016] Furthermore, instead of console 23, injection system 120 may have a control device connected to injection head 20, and a display unit (e.g., a tablet terminal or a touch panel display) connected to the control device and separate from the control device that displays the injection status of the medicinal liquid. In this case, the control device functions as simulator 40 that predicts changes in pixel values ​​over time. In addition, injection head 20 and the control device can be configured integrally with stand 22. Furthermore, a hanging member can be provided instead of stand 22, and injection head 20 can be suspended from the ceiling via the hanging member.

[0017] Injection head 20 may also have a remote control device (e.g., a hand switch or foot switch) for remotely controlling injection head 20. This remote control device can remotely control injection head 20 to start or stop injection. Injection head 20 may also have a power source or battery. This power source or battery can be provided in either injection head 20 or the control device, or can be provided separately from these.

[0018] The injection head 20 includes a syringe holder on which a syringe filled with a liquid medicine is mounted, and a drive mechanism for pushing out the liquid medicine in the syringe according to an injection protocol. The injection head 20 also includes an operation unit 28 for inputting the operation of the drive mechanism. The operation unit 28 includes, for example, a forward button for the drive mechanism, a backward button for the drive mechanism, and a final confirmation button. The injection head 20 may also include a head display on which the injection conditions, the injection status, the input status of the device, the setting status, and various injection results are displayed. For example, the head display is installed on the side of the injection head 20 or is built into the injection head 20. The head display may also be a touch panel type display that can be operated by an operator. In this case, the head display may display the screens shown in FIG. 3 to FIG. 6.

[0019] When the contrast medium is injected, an accessory such as an extension tube is connected to the tip of the syringe mounted on injection head 20. Then, when preparation for injection is complete, the operator presses the final confirmation button on operation unit 28. Alternatively, the operator may touch the final confirmation button displayed on touch panel 26. This puts injection head 20 into a standby state in which injection can begin. When injection is then started, the contrast medium pushed out of the syringe is injected into the subject via the extension tube.

[0020] In addition, the injection head 20 may be capable of mounting a pre-filled syringe having a data carrier such as an RFID chip, an IC tag, or a barcode, and various other syringes. The data carrier stores drug information related to the drug solution. When a syringe having a data carrier can be mounted, the injection head 20 is provided with a reading unit that reads the data carrier attached to the syringe. Furthermore, the injection head 20 may have three or more syringe holders, or may have only one syringe holder.

[0021] Injection head 20 can receive information from an external storage device (not shown), such as a server S (FIG. 2), and can transmit information to server S. Imaging device 30 of imaging system 130 can also receive information from server S and transmit information to server S. This server S is, for example, a Radiology Information System (RIS), a Picture Archiving and Communication System (PACS), or a Hospital Information System (HIS).

[0022] The server S stores an examination order in advance. The examination order includes subject information on the subject and examination information on the examination content. The server S can also store information on the imaging results, such as image data transmitted from the imaging device 30, and information on the injection results transmitted from the injection head 20. An external image inspection system or an image creation workstation can also be used to operate the injection head 20 and the imaging device 30. Furthermore, a device (e.g., a tablet terminal) that can remotely operate the injection head 20 may be provided inside or outside the hospital.

[0023] The imaging system 130 includes a medical imaging device 30 that captures an image of a subject, and the imaging device 30 is connected to the injection system 120 by wire or wirelessly. Examples of the imaging device 30 include various medical imaging devices such as an MRI (Magnetic Resonance Imaging) device, a CT (Computed Tomography) device, an angio imaging device, a PET (Positron Emission Tomography) device, a SPECT (Single Photon Emission Computed Tomography) device, a CT angio device, an MR angio device, an ultrasound diagnostic device, and a blood vessel imaging device. An example in which the imaging system 130 includes a CT device will be described below.

[0024] The imaging device 30 has an imaging section 31 that images a subject according to an imaging plan, and a control device 32 that controls the entire imaging device 30. The imaging plan includes, for example, an imaging site, an effective tube voltage, a model name, a manufacturer name, an imaging time, a tube voltage, an imaging range, a rotation speed, a helical pitch, an exposure time, a dose, and an imaging method. The control device 32 controls the imaging section 31 to image the subject according to the imaging plan. Furthermore, the control device 32 may also function as a simulator 40 that predicts a change in pixel value over time in a selected site. The control device 32 can communicate with the imaging section 31, the injection head 20, and the server S by wire or wirelessly. The simulator 40 of the imaging device 30 may perform a more accurate simulation by further considering information included in the imaging plan.

[0025] The imaging unit 31 has a bed, an X-ray source that irradiates the subject with X-rays, and an X-ray detector that detects the X-rays that have passed through the subject. The imaging unit 31 irradiates the subject with X-rays and captures a perspective image of the subject by back-projecting the inside of the subject based on the X-rays that have passed through the subject.

[0026] The imaging device 30 has a display 33. The display 33 is connected to the control device 32 and displays the input state, setting state, imaging result, and various information of the device. When the control device 32 also functions as the simulator 40, the display 33 also functions as a display unit that displays a simulation screen described later. Alternatively, the control device 32 and the display 33 can be configured integrally. Furthermore, the imaging device 30 has an interface 34 such as a keyboard that functions as an input unit. An operator can input information including drug solution information, injection protocol, tissue information, subject information, target value, etc. to the imaging device 30 from the interface 34. The display 33 may be a touch panel that functions as an input display unit. In this case, the display 33 also functions as a substitute for the interface 34.

[0027] [simulator] With reference to Fig. 2, a simulator 40 (e.g., a perfusion simulator) that predicts changes over time in pixel values ​​in a selected region selected by an operator as an imaging region from among tissues of a subject will be described. The console 23 includes the simulator 40 and a touch panel 26 as an input display unit. The simulator 40 includes a control unit 41 and a storage unit 42 that stores a control program PG. When the console 23 functions as the simulator 40 as a whole, the simulator 40 includes the touch panel 26 as a display unit.

[0028] As an example, the control unit 41 is configured as a computer that combines a processor that executes various calculation processes and operation control according to a predetermined program, an internal memory required for the operation of the processor, and other peripheral devices. The processor is, for example, a CPU (Central Processing Unit) or an MPU (Micro-Processing Unit), and controls the entire injection system 120 and also controls various processes in a comprehensive manner based on a control program PG stored in the storage unit 42. In this embodiment, the CPU executes various processing operations such as calculations, control, and discrimination according to the control program PG stored in the storage unit 42. In addition, a touch panel 26 is connected to the control unit 41 as an input unit for inputting predetermined commands and data. The touch panel 26 also functions as a display unit that displays the input state, setting state, measurement results, and various information of the device. Furthermore, the control unit 41 may perform control according to a program stored in a portable recording medium such as a CD (Compact Disc), a DVD (Digital Versatile Disc), a CF (Compact Flash) card, and a USB (Universal Serial Bus) memory, or an external storage medium such as a server S connected to the Internet or a LAN.

[0029] The control unit 41 controls each part of the simulator 40 according to the control program PG stored in the storage unit 42. The control unit 41 has an information acquisition unit 43, an injection condition acquisition unit 44, a target value acquisition unit 45, a prediction unit 46, a determination unit 47, and a display control unit 48. Each part is a logical device realized by a combination of the hardware resources of the control unit 41 and the control program PG as a software resource. At least a part of these logical devices may be provided outside the console 23. In this case, the control unit 41 has only a part of these logical devices.

[0030] The storage unit 42 is a non-transitory computer-readable recording medium. The storage unit 42 includes a RAM (Random Access Memory) that is a system work memory for the processor of the control unit 41 to operate, a ROM (Read Only Memory) that stores programs and system software, and storage devices such as an HDD (Hard Disc Drive) and an SSD (Solid State Drive).

[0031] The storage unit 42 also stores a control program PG, which also functions as a simulation program for simulating pixel values ​​at a selected site. This control program PG causes the control unit 41, which is a computer, to function as an information acquisition unit 43, an injection condition acquisition unit 44, a target value acquisition unit 45, a prediction unit 46, a judgment unit 47, and a display control unit 48. The control program PG can also be stored in a computer-readable non-transitory recording medium. The storage unit 42 also stores reference data RD that is referenced during simulation and display of a simulation screen. For example, the reference data RD includes threshold value specification information that specifies an upper limit or lower limit of pixel values, an image (e.g., an image simulating an organ) used to display the simulation result, and information (e.g., brightness) that indicates the display mode of the image according to the judgment result.

[0032] The information acquiring unit 43 acquires site information, subject information, medicinal liquid information, and examination information related to the examination. For example, the information acquiring unit 43 acquires various information input by the operator via the touch panel 26. Specifically, the information acquiring unit 43 acquires the name of a site that specifies a selected site as the site information input by the operator. As an example, the names of the sites are head, brain, chest, coronary artery, right ventricle, left ventricle, abdomen, lower limbs, upper limbs, lungs, liver, stomach, spleen, pancreas, intestinal tract, kidneys, ascending aorta, descending aorta, and abdominal aorta. Furthermore, the information acquiring unit 43 may acquire various information from an external device connected to the console 23. For example, the information acquiring unit 43 may acquire a heart rate as subject information from a pulse oximeter as a measuring device that acquires biological information of the subject.

[0033] Furthermore, the information acquisition unit 43 may acquire various pieces of information from the storage unit 42 of the simulator 40 or the server S. When acquiring information from the server S, the console 23 and the server S function as the simulator 40 as a whole. Examples of the server S include a RIS, a PACS, an HIS, an image inspection system, and a workstation for creating images. The server S is configured as one logical server S by combining server units as multiple computers. However, the server S may be configured from a single server unit. Alternatively, the server S may be configured logically by using cloud computing. The server S is configured as a computer that combines a processor that executes various types of arithmetic processing and operation control according to a predetermined program, an internal memory required for the operation of the processor, and other peripheral devices.

[0034] Furthermore, information acquiring unit 43 may acquire various information from imaging device 30 or injection head 20. For example, injection head 20 acquires the iodine content as medicinal solution information from a reading unit built into injection head 20. Then, information acquiring unit 43 acquires the iodine content from injection head 20. As one example, the reading unit is a non-contact reading device that reads the medicinal solution information from a data carrier attached to a syringe mounted on injection head 20.

[0035] The site information acquired by the information acquisition unit 43 may include tissue information of the subject in addition to information specifying the selected site. The tissue includes the heart, right ventricle, left ventricle, blood vessels, kidneys, ureters, other organs, and muscles. As an example, the tissue information includes the number of divided compartments in blood vessels and organs as tissues, the volume of the tissue, the volume of the vascular cavity, the volume of the capillaries, the volume of the extracellular fluid cavity, the blood flow rate per unit tissue, the blood flow velocity per unit tissue, the seepage rate of the contrast agent in the tissue, the capillary permeable surface area, the seepage back rate of the contrast agent in the tissue, the capillary permeable surface area, and the inherent pixel value of the tissue. The number of compartments may be set to be greater for tissues with a larger volume than for tissues with a smaller volume.

[0036] The subject information acquired by the information acquisition unit 43 includes, for example, the amount of iodine per body weight, sex, body weight, height, body surface area, cardiac function, heart rate, stroke volume, cardiac output, hemoglobin amount, estimated glomerular filtration rate (eGFR), creatinine level, age, lean body mass, body mass index, circulating blood volume, subject number, subject ID, subject's disease and side effect history, subject's name, date of birth, blood volume, and blood flow rate. The medicinal liquid information acquired by the information acquisition unit 43 includes, for example, the iodine content, the amount of iodine per unit, viscosity, osmotic pressure ratio, filling amount, product ID, product name, chemical classification, contained components, concentration, expiration date, syringe capacity, syringe pressure resistance, cylinder inner diameter, piston stroke, and lot number.

[0037] Furthermore, the examination information acquired by the information acquisition unit 43 includes, for example, information identifying the imaging site, pressure limit, amount of iodine per body weight per unit time (hereinafter also referred to as amount of iodine used), tube voltage (kV), examination number, examination ID, examination date and time, type of liquid medicine, name of liquid medicine, and characteristics of the imaging device 30. The information identifying the imaging site is information that can identify the site or range selected as the imaging target. For example, the information identifying the imaging site includes the name of the examination site, the name of the imaging method, or the distance from the injection site of the liquid medicine to the examination site. Note that, if not required for the simulation, the information acquisition unit 43 does not need to acquire any of the site information, subject information, liquid medicine information, and examination information.

[0038] The injection condition acquisition unit 44 acquires an injection protocol, which is an injection condition for the contrast agent. As an example, the injection condition acquisition unit 44 generates an injection protocol based on various information acquired from the information acquisition unit 43, and thereby acquires the injection protocol. The injection condition acquisition unit 44 may also acquire an injection protocol input by an operator via the simulator 40. The injection condition acquisition unit 44 may also acquire an injection protocol from the storage unit 42, the server S, the injection head 20, or the imaging device 30. As an example, the injection protocol includes an injection time and an injection speed of the medicinal liquid. Furthermore, the injection protocol may be composed of a plurality of injection phases. For example, the confirmation screen shown in FIG. 3 displays an injection protocol consisting of a first phase for injecting a contrast agent, a second phase for injecting a contrast agent and saline, and a third phase for injecting saline.

[0039] For example, the injection protocol may include information such as the injection method, the injection site of the liquid medicine, the injection amount, the mixed injection ratio, the injection timing, the contrast agent concentration, the injection pressure, the acceleration of the injection speed, the injection time and the injection speed of each liquid medicine, the presence or absence of boost injection of the contrast agent by saline, the increase or decrease of the injection speed, the presence or absence of cross injection, the presence or absence of link speed setting, and the volume of the injection tube. The cross injection is an injection method in which the contrast agent is injected at a speed faster than the injection speed of the saline until a set time has elapsed from the start of the injection, and then the contrast agent is injected so that the injection speed gradually decreases, and at the same time, the saline is injected so that the injection speed gradually increases. The link speed setting is a setting in which the injection speeds of the contrast agent and the saline are linked so that they are the same.

[0040] Furthermore, the injection condition acquisition unit 44 may generate an injection protocol based on the target value acquired by the target value acquisition unit 45. In this case, the injection condition acquisition unit 44 may generate an injection protocol that realizes a simulation result (e.g., a time-concentration curve or a time-enhancement curve) by the prediction unit 46. Furthermore, the injection condition acquisition unit 44 may generate an injection protocol based on the examination information, the subject information, and the medicinal solution information.

[0041] The target value acquisition unit 45 acquires a target pixel value required for interpretation of the imaging site as a target value. The operator can input the target pixel value from the touch panel 26. The target value acquisition unit 45 may also acquire a desired target maintenance time for maintaining the target pixel value as a target value. The operator can input the target maintenance time from the touch panel 26. Alternatively, the target value acquisition unit 45 may acquire the target value from the injection head 20, the imaging device 30, the storage unit 42, or the server S. If the operator does not input a target value, or before the operator inputs a target value, the target value acquisition unit 45 may acquire a preset target value. The preset target value is stored in the storage unit 42. This allows a simulation result to be obtained even if the operator does not input a target value.

[0042] The prediction unit 46 simulates pixel values ​​in the selected region when the contrast agent is injected according to a predetermined injection condition. For example, the prediction unit 46 acquires an injection protocol from the injection condition acquisition unit 44 as the predetermined injection condition. As an example, the injection condition acquisition unit 44 calculates the injection time and injection speed of the contrast agent and physiological saline as the injection protocol based on the selected region, the subject's body weight, and the amount of iodine in the contrast agent. In addition, the prediction unit 46 acquires site information, subject information, drug solution information, and examination information from the information acquisition unit 43, and simulates the change over time of pixel values ​​in each tissue of the subject. An example of the simulation by the prediction unit 46 will be described below.

[0043] Each tissue of the subject is divided into a plurality of compartments along the blood flow direction according to the number of compartments of the tissue based on the tissue information acquired by the information acquisition unit 43. The prediction unit 46 divides the volume of the tissue including the compartment of each tissue to be predicted, the capillary volume of the tissue, and the extracellular fluid space volume of the tissue by the number of compartments to predict the change in pixel value over time for each compartment. The tissue of the subject also includes the right ventricle, aorta, vein, artery, brain (or head), upper limbs, myocardium (e.g., myocardium dominated by the right coronary artery, myocardium dominated by the anterior descending artery, and myocardium dominated by the circumflex artery), lung, liver, stomach, spleen, pancreas, intestine, kidney, ureter, lower limbs, left ventricle, ascending aorta, descending aorta, and abdominal aorta. The contrast medium injected from the upper limb vein travels to each organ via the right ventricle, lungs, left ventricle, and aorta (e.g., the ascending aorta and the descending aorta), and then reaches the right ventricle via the vein. The contrast medium injected into the body is then discharged from the body via the kidneys and ureters.

[0044] To obtain the change in pixel value of each tissue as a function of time, prediction unit 46 uses a differential equation such as the following formula 1. Here, the concentration of the contrast agent flowing into a compartment is C1, the concentration of the contrast agent flowing out of the compartment is C2, the volume of the compartment is V, and the blood flow rate (blood flow velocity) per unit tissue in the compartment is Q.

[0045]

number

[0046] Furthermore, in order to obtain changes in pixel values ​​in the right ventricle, the left ventricle, and tissues other than blood vessels, the prediction unit 46 considers the seepage speed when the contrast agent permeates from the capillaries to the extracellular fluid space and the seepage back speed when the contrast agent permeates from the extracellular fluid space to the capillaries. For this purpose, the prediction unit 46 uses differential equations such as the following formulas 2 and 3. Here, the volume of the extracellular fluid space is Vec, the concentration of the contrast agent in the extracellular fluid space is Cec, the volume of the capillaries is Viv, the concentration of the contrast agent in the capillaries is Civ, the seepage speed is PS1, and the seepage back speed is PS2.

[0047]

number

[0048]

number

[0049] The prediction unit 46 solves the differential equation to obtain the time elapsed from the start of injection and the change in the contrast agent concentration corresponding to the pixel value as a function of time. Furthermore, the prediction unit 46 may calculate the discharge amount of the contrast agent based on a predetermined discharge rate and perform a simulation by subtracting the discharge amount from the contrast agent in the capillaries of the kidney. In this way, a simulation is performed such that a part of the contrast agent that has reached the kidney is subtracted from the total amount of contrast agent in the whole body (in the plasma). By simulating the discharge of the contrast agent, the total amount of contrast agent in the whole body decreases over time, so that a more accurate simulation can be performed. Alternatively, the prediction unit 46 may perform a simulation using a known pharmacokinetic model such as the method described in Japanese Patent No. 3553968.

[0050] When the simulation is completed, the prediction unit 46 sequentially stores the simulation results in the storage unit 42. The simulation results include information on pixel values ​​for each time associated with each tissue. The tissue corresponding to the selected region can be identified based on the region information. The simulation results may also include a time-density curve (TDC) or a time enhancement curve (TEC) showing the change over time of pixel values ​​in the examination region. In addition, the simulation results may include information on pixel values ​​for each time associated with the tissue. Furthermore, the simulation results may include the length of time (e.g., the number of seconds) during which the pixel values ​​of the selected region are maintained in a state lower than the upper limit value and higher than the lower limit value. Alternatively, the prediction unit 46 may use other known methods for simulating the systemic circulation of the contrast agent.

[0051] Furthermore, the prediction unit 46 receives from the information acquisition unit 43, as subject information, the hemoglobin amount (g / dL), weight (kg), height (cm), cardiac function (%), heart rate (bpm), and body surface area (m 2 ), cardiac output (L / min), and eGFR. This allows the prediction unit 46 to perform a more accurate high-precision simulation based on more information. As a result, for example, to perform a surgery simulation or to determine a treatment plan, an image with higher image quality can be captured or a three-dimensional image can be created. The prediction unit 46 may calculate at least one of the body surface area, cardiac output, and estimated glomerular filtration rate and use it in the simulation. For example, the body surface area can be calculated by the Fujimoto formula, Dubois formula, or Shintani formula based on the weight and height. The cardiac output can be calculated based on the body surface area, cardiac function, and heart rate. The eGFR can be calculated based on the creatinine value, age, and sex.

[0052] The determination unit 47 determines whether the pixel value is higher than the upper limit value and whether the pixel value is lower than the lower limit value based on the simulation result by the prediction unit 46. For example, the determination unit 47 acquires information identifying the selected site as site information from the information acquisition unit 43, and identifies the tissue corresponding to the selected site. The determination unit 47 also acquires threshold identifying information of the selected site by referring to the reference data RD. Then, the determination unit 47 acquires a target pixel value from the target value acquisition unit 45, and identifies the upper limit value and the lower limit value of the pixel value based on the threshold identifying information.

[0053] The threshold specifying information is set for each tissue of the subject. For example, in the case of a coronary artery, the information specifying the upper limit is "plus 50 HU" and the information specifying the lower limit is "minus 50 HU". Therefore, when the target pixel value is 400 HU, the upper limit is 450 HU and the lower limit is 350 HU. The threshold specifying information may be the upper or lower limit pixel value, for example, the information specifying the upper limit may be "450 HU" and the information specifying the lower limit may be "350 HU". Furthermore, the threshold specifying information may be a ratio to the target pixel value, for example, the information specifying the upper limit may be "plus 10%" and the information specifying the lower limit may be "minus 10%". In this case, when the target pixel value is 400 HU, the upper limit is 440 HU and the lower limit is 360 HU.

[0054] For example, the determination unit 47 compares the peak value of the pixel value during the maintenance time with the upper limit value and the lower limit value to determine whether the pixel value is higher than the upper limit value and whether the pixel value is lower than the lower limit value. Alternatively, the determination unit 47 may compare the average value or median value of the pixel value during the maintenance time with the upper limit value and the lower limit value. The determination unit 47 may also compare the pixel value at the imaging timing when the imaging device 30 performs imaging with the upper limit value and the lower limit value. In this case, the imaging timing may be determined by the determination unit 47, or may be acquired by the determination unit 47 from the imaging device 30, the storage unit 42, the server S, or the injection head 20. As an example, the injection head 20 can acquire the imaging timing by detecting a sound or the like during exposure using a built-in or connected sensor.

[0055] Furthermore, the determination unit 47 may determine, as the imaging timing, a predetermined timing during the maintenance time during which the pixel value of the selected site is maintained in a state lower than the upper limit value and higher than the lower limit value. In the imaging device 30 such as a CT device, the imaging timing is the exposure timing at which X-rays are irradiated. For example, the determination unit 47 determines, as the imaging timing, the timing at the center of the maintenance time. Alternatively, the determination unit 47 may determine, as the imaging timing, the timing at which the pixel value reaches a peak value during the maintenance time. The determination unit 47 passes, as information specifying the determined imaging timing, for example, the elapsed time from the start of injection to the imaging timing, or the time of the imaging timing, to the display control unit 48.

[0056] When the pixel value in the selected region is higher than the upper limit based on the determination result by the determination unit 47, the display control unit 48 causes the touch panel 26 to display a first part image 61A (FIG. 6), which is an example of a first image. When the pixel value in the selected region is lower than the lower limit, the display control unit 48 causes the touch panel 26 to display a second part image 61B (FIG. 5), which is an example of a second image having a different display mode from the first part image 61A. This allows the operator to determine that the pixel value in the selected region meets the desired condition if neither the first part image 61A nor the second part image 61B is displayed. In other words, when neither the first part image 61A nor the second part image 61B is displayed, the pixel value in the selected region is maintained within a predetermined range from the target pixel value. When the pixel value in the selected region is higher than the upper limit, the display control unit 48 may cause the touch panel 26 to display a character string indicating that the pixel value is higher than the upper limit, and when the pixel value in the selected region is lower than the lower limit, the display control unit 48 may cause the touch panel 26 to display a character string indicating that the pixel value is lower than the lower limit. In these cases, the injection condition acquisition unit 44 may generate an injection protocol that realizes an optimal time-density curve or time-enhancement curve. The display control unit 48 displays the generated injection protocol.

[0057] Furthermore, when the pixel value of the selected part is lower than the upper limit value and higher than the lower limit value, the display control unit 48 causes the touch panel 26 to display a third part image 61C (FIG. 4), which is an example of a third image having a different display mode from the first part image 61A and the second part image 61B. This allows the operator to determine that the pixel value of the selected part satisfies the desired condition if the third part image 61C is displayed. That is, if neither the first part image 61A nor the second part image 61B is displayed, but the third part image 61C is displayed, the pixel value of the selected part is maintained within a predetermined range from the target pixel value. The first part image 61A, the second part image 61B, and the third part image 61C may be an image imitating an organ, an image imitating a human body, an image imitating a part of a human body, or any other arbitrary image. Furthermore, the first part image 61A, the second part image 61B, and the third part image 61C may be displayed so as to be superimposed on the image imitating a human body.

[0058] Furthermore, the display control unit 48 causes the first part image 61A and the second part image 61B to be displayed so that the first part image 61A has a higher brightness than the second part image 61B, thereby making the display modes of both images different. The display control unit 48 also causes the first part image 61A, the second part image 61B, and the third part image 61C to be displayed so that the first part image 61A has a higher brightness than the third part image 61C, and the second part image 61B has a lower brightness than the third part image 61C, thereby making the display modes of each image different. Alternatively, the display control unit 48 may display each of the first part image 61A, the second part image 61B, and the third part image 61C so that the size, brightness, density, saturation, contrast, or resolution of each of the first part image 61A, the second part image 61B, and the third part image 61C are different from each other. Furthermore, the display control unit 48 may change the display manner so as to highlight the third part image 61C more than the first part image 61A and the second part image 61B. Examples of the highlighting manner include changing the color, shape, or size of the image, blinking of the image, and movement of the image.

[0059] Furthermore, the display control unit 48 causes the touch panel 26 to display a length image 62 (FIG. 4) as an image indicating the length of time during which the pixel value of the selected site is maintained in a state lower than the upper limit value and higher than the lower limit value, in a size corresponding to the length of the maintenance time. That is, the display control unit 48 causes the length image 62 to be displayed in a larger or longer size if the maintenance time is longer, and in a smaller or shorter size if the maintenance time is shorter. For example, the display control unit 48 causes the length image 62 to be displayed on an axis line indicating the elapsed time from the start of injection. This allows the operator to grasp the length of time during which the pixel value is maintained within a predetermined range from the target pixel value. Furthermore, the display control unit 48 may cause the touch panel 26 to display a character string (e.g., seconds) indicating the length of the maintenance time.

[0060] Furthermore, the display control unit 48 displays an instruction image 63 (FIG. 4) on the touch panel 26 as information indicating the imaging timing. For example, the display control unit 48 acquires the elapsed time from the start of injection to the imaging timing from the determination unit 47 as information specifying the imaging timing. Then, the display control unit 48 displays, for example, the instruction image 63 indicating the imaging timing as information indicating the imaging timing, so as to be aligned with an axis indicating the elapsed time from the start of injection. Note that the imaging timing may be one point in time within the maintenance time, or may be a predetermined time range within the maintenance time. For example, when the imaging timing is a time range, the imaging timing is a range consisting of a predetermined length of time before the center of the maintenance time and a predetermined length of time after the center. Alternatively, the display control unit 48 may display, instead of or in addition to an image, a character string indicating the elapsed time from the start of injection to the imaging timing on the touch panel 26 as information indicating the imaging timing. Note that the display control unit 48 may acquire information specifying the imaging timing, for example, the time of the imaging timing, from a device external to the console 23, for example, the imaging device 30.

[0061] [Screen Description] Before displaying the simulation screens shown in FIGS. 4 to 6, the display control unit 48 displays the confirmation screen shown in FIG. 3 on the touch panel 26. When the operator selects a region on the initial screen (not shown), the display control unit 48 displays the confirmation screen. When the injection head 20 is started, the display control unit 48 displays the initial screen on the touch panel 26. For example, a silhouette image imitating a human body is displayed on the initial screen, and the operator touches a region on the silhouette image. This allows the operator to select the region touched as the selected region. When the selected region is selected, an input screen for inputting subject information, examination information, target values, and the like is displayed on the initial screen. For example, the operator touches a numeric keypad image displayed on the input screen to input the weight as subject information, the pressure limit and the amount of iodine used as examination information, and the target pixel value and target maintenance time as target values. Each operation by the operator may be a touch operation, a tap operation, a flick operation, a swipe operation, a pinch-in operation, and a pinch-out operation, or may be an operation using an operating device such as a mouse or a keyboard.

[0062] When a certain time has elapsed since the operator inputs the subject information and the like, the display control unit 48 causes the touch panel 26 to display the confirmation screen shown in FIG. 3. The display control unit 48 may display the confirmation screen instead of the initial screen, or may display the confirmation screen together with the initial screen. Alternatively, the display control unit 48 may display the confirmation screen in response to an operation by the operator to display the confirmation screen. The confirmation screen is provided with a liquid medicine information field 51 in which liquid medicine information is displayed. For example, the display control unit 48 causes the liquid medicine information field 51 to display the contrast medium and the amount of saline solution filled in the syringe mounted on the injection head 20 as the liquid medicine information acquired from the information acquisition unit 43. In the example of FIG. 3, the liquid medicine information field 51 displays the contrast medium filling amount of 140 mL and the saline filling amount of 150 mL. Furthermore, the confirmation screen is provided with an examination information field 52 in which examination information is displayed. For example, the display control unit 48 causes the examination information field 52 to display the pressure limit and the amount of iodine used as the examination information input by the operator. In the example of Fig. 3, a pressure limit of 300 psi and an iodine volume of 22.2 mgI / kg / sec as the amount of iodine used are displayed in the examination information field 52. Note that input of the next information (e.g., examination information or target value) may be restricted until the operator inputs subject information such as weight. If the operator does not perform any operation for a certain period of time after each piece of information is input, the display control unit 48 may automatically display the registered icon or information input screen.

[0063] The confirmation screen is provided with an injection time field 53 in which the injection time is displayed. In the example of FIG. 3, the injection time of the contrast medium, 15 sec, is displayed in the injection time field 53. The injection time field 53 may display the injection time of the saline solution, the injection time of the mixed injection, or the total injection time of all the liquid medicines. Furthermore, the confirmation screen is provided with a subject information field 54A in which the subject information is displayed. For example, the display control unit 48 displays the weight in the subject information field 54A as the subject information input by the operator. In the example of FIG. 3, the weight of 58 kg is displayed in the subject information field 54A. Furthermore, the confirmation screen of FIG. 3 is provided with a biological information field 54B in which the biological information of the subject is displayed. For example, the display control unit 48 displays the heart rate in the biological information field 54B as the biological information acquired by the information acquisition unit 43 from the measurement device. In the example of FIG. 3, the heart rate of 60 bpm is displayed in the biological information field 54B. However, when biological information is not acquired from the measurement device, the biological information field 54B may be omitted. Furthermore, the confirmation screen is provided with a liquid medicine name field 55 in which the product name of the contrast agent is displayed as the liquid medicine name. For example, display control unit 48 causes the product name of the contrast agent filled in the syringe to be displayed in liquid medicine name field 55 as the liquid medicine name acquired from information acquisition unit 43. In the example of FIG. 3, the product name "ABC" is displayed in liquid medicine name field 55. The name or logo of the manufacturer of the liquid medicine may also be displayed, and the product name and the name or logo of the manufacturer may be displayed after the reading unit of injection head 20 reads the liquid medicine information. Furthermore, the amount of iodine per unit of the contrast agent may be displayed.

[0064] The confirmation screen also has a selected site field 56 in which information identifying the selected site is displayed. For example, the display control unit 48 displays the site name and an image indicating the site in the selected site field 56 as information identifying the selected site input by the operator. In the example of FIG. 3, an image indicating the chest in a silhouette image of a human body and the site name "Coronary Artery" are displayed in the selected site field 56. The confirmation screen also has an injection condition field 57 in which injection conditions are displayed. For example, the display control unit 48 displays an injection protocol in the injection condition field 57 as liquid information acquired from the injection condition acquisition unit 44. In the example of FIG. 3, an injection protocol is displayed that includes a first phase in which the injection rate of the contrast agent is 6.4 mL / sec and the injection amount is 58 mL, a second phase in which the injection rates of the contrast agent and saline are 2.2 mL / sec and the injection amount is 13 mL, and a third phase in which the injection rate of the saline is 2.5 mL / sec and the injection amount is 20 mL. Furthermore, for example, when a contrast medium and saline solution are mixed and injected, a mark M or a character string indicating a recommended device (for example, "SPIRAL FLOW (registered trademark)" manufactured by Nemoto Kyorindo Co., Ltd.) may be displayed. By using the device, the medicinal liquid can be mixed with high precision. In the second phase, 26 mL of the mixed solution of the contrast medium and saline solution is injected at an injection speed of 4.4 mL / sec.

[0065] Furthermore, the confirmation screen displays an air check button 58 and a simulation start or display button 59. The operator can complete preparation for injection by touching air check button 58. When the operator touches air check button 58, display control unit 48 displays a start button (not shown) in place of air check button 58. The operator can start injection by touching the start button. The operator can also start injection by pressing a start switch provided on operation unit 28 of injection head 20. Furthermore, the operator may be able to start injection by operating a remote operation device.

[0066] Furthermore, when the operator flicks the start or display button 59, the display control unit 48 causes the touch panel 26 to display the simulation screen shown in Fig. 4 to Fig. 6. When the operator does not perform any operation on the simulation screen for a certain period of time, the display control unit 48 causes the confirmation screen to be displayed again. In this case, the display control unit 48 may cause the confirmation screen to be displayed instead of the simulation screen, or may cause the confirmation screen to be displayed together with the simulation screen.

[0067] As shown in FIG. 4 to FIG. 6, the simulation screen is provided with an examination information field 52, an injection time field 53, a biological information field 54B, a selected region field 56, and an injection condition field 57. The display control unit 48 displays these fields in the same manner as the confirmation screen shown in FIG. 3, and therefore the description thereof will be omitted. As shown in FIG. 4, the simulation screen is provided with a result field 60 showing the determination result. The display control unit 48 displays the result field 60 so as to be expanded in synchronization with the operator's flick operation. Alternatively, the display control unit 48 may display the result field 60 in a pop-up so as to be superimposed on the confirmation screen. In this result field 60, an image simulating the heart including the coronary artery is displayed as a third region image 61C. When the determination unit 47 determines that the pixel value of the selected region is lower than the upper limit value and higher than the lower limit value, the display control unit 48 displays the third region image 61C.

[0068] The prediction unit 46 starts the simulation when the display control unit 48 displays the confirmation screen. That is, the prediction unit 46 starts the simulation when the operator inputs the subject information and a certain time has passed. Then, when the simulation ends, the prediction unit 46 stores the simulation result in the storage unit 42. Also, the judgment unit 47 executes judgment at any timing after the simulation ends and stores the judgment result in the storage unit 42. Then, the display control unit 48 develops the result field 60 in which the first part image 61A, the second part image 61B, or the third part image 61C is displayed according to the judgment result. Alternatively, the prediction unit 46 may start the simulation when the operator operates the start or display button 59. In parallel, when the operator operates the start or display button 59, the display control unit 48 develops the result field 60. Then, the judgment unit 47 performs a judgment after the simulation is completed, and depending on the judgment result, the display control unit 48 displays the first part image 61A, the second part image 61B, or the third part image 61C in the expanded result field 60.

[0069] Furthermore, the display control unit 48 displays a length image 62 indicating the length of the maintenance time on an axis indicating the time elapsed from the start of injection in the result field 60. In the example of Fig. 4, the maintenance time is shown as 15 seconds between the timing when 20 seconds have elapsed from the start of injection and the timing when 35 seconds have elapsed from the start of injection. Furthermore, the display control unit 48 displays an instruction image 63 indicating the imaging timing in line with the axis in the result field 60. Note that at least one of the length image 62 and the instruction image 63 may be omitted.

[0070] Furthermore, the display control unit 48 displays the target pixel value, the target retention time, and the tube voltage in the result field 60. In the example of FIG. 4, a target CT value of 400HU is displayed as the target pixel value, a retention time of 15 sec is displayed as the target retention time, and a tube voltage of 120 kVp is displayed as the tube voltage. The display control unit 48 may display a simulation screen so that the operator can change at least one of the target pixel value, the target retention time, and the tube voltage. For example, when the operator touches a value to be changed, the display control unit 48 pops up a numeric keypad image for input. When a change is made, a re-simulation may be performed. When biological information (e.g., heart rate) of the subject acquired by the measuring device changes, a re-simulation may be performed. In these cases, the determination unit 47 performs a determination after the end of the simulation, and the display control unit 48 displays the first part image 61A, the second part image 61B, or the third part image 61C in the expanded result field 60 according to the determination result.

[0071] In the simulation screen shown in Fig. 5, display control unit 48 displays each column in the same manner as in the simulation screen shown in Fig. 4, except for result column 60. Therefore, result column 60 will be described below. In result column 60 shown in Fig. 5, an image simulating the heart including coronary arteries is displayed as second part image 61B. When determination unit 47 determines that the pixel value in the selected part is lower than the lower limit value, display control unit 48 displays second part image 61B.

[0072] In the simulation screen shown in Fig. 6, display control unit 48 displays each column in the same manner as in the simulation screen shown in Fig. 4, except for result column 60. Therefore, result column 60 will be described below. In result column 60 shown in Fig. 6, an image simulating the heart including coronary arteries is displayed as first part image 61A. When determination unit 47 determines that the pixel value in the selected part is higher than the upper limit value, display control unit 48 causes first part image 61A to be displayed.

[0073] As shown in the result column 60 in FIG. 4 to FIG. 6, the display control unit 48 displays one of the first part image 61A, the second part image 61B, and the third part image 61C according to the judgment result. The first part image 61A shown in FIG. 6 is brighter and displayed whiter than the second part image 61B shown in FIG. 5 and the third part image 61C shown in FIG. 4. This allows the operator to intuitively and visually recognize the simulation result that the pixel value in the selected part is higher than the upper limit value. The second part image 61B shown in FIG. 5 is brighter and displayed blacker than the first part image 61A shown in FIG. 6 and the third part image 61C shown in FIG. 4. This allows the operator to visually recognize the simulation result that the pixel value in the selected part is lower than the lower limit value.

[0074] Furthermore, the third part image 61C shown in FIG. 4 is displayed darker and less bright than the first part image 61A shown in FIG. 6, and is displayed whiter and more bright than the second part image 61B shown in FIG. 5. This allows the operator to visually recognize the simulation result that the pixel value in the selected part is in the range between the upper limit and the lower limit. The display control unit 48 may cause the display mode of only a part of the first part image 61A, the second part image 61B, and the third part image 61C to differ from that of the other images. For example, the display control unit 48 may cause only the part of the first part image 61A, the second part image 61B, and the third part image 61C corresponding to the coronary artery to differ from that of the other images. Similarly, in an example in which the selected part is the right ventricle, the display control unit 48 may cause only the part corresponding to the right ventricle to differ from that of the other images. Furthermore, the display control unit 48 may display images imitating organs corresponding to the selected part as the first part image 61A, the second part image 61B, and the third part image 61C. For example, when the selected part is the liver, the display control unit 48 may display images imitating the liver.

[0075] In addition, in the result field 60 shown in FIG. 5, a second position image 64B is displayed as another example of the second image. In the result field 60 shown in FIG. 6, a first position image 64A is displayed as another example of the first image in a different display manner from the second position image 64B. The second position image 64B has a different display manner from the first position image 64A in that the display positions are different. That is, the second position image 64B is displayed below the target pixel value. This allows the operator to intuitively and visually recognize the simulation result that the pixel value in the selected region is lower than the lower limit value. In addition, the first position image 64A has a different display manner from the second position image 64B in that the display positions are different. That is, the first position image 64A is displayed above the target pixel value. This allows the operator to visually recognize the simulation result that the pixel value in the selected region is higher than the upper limit value. Note that the first position image 64A and the second position image 64B may have different display modes, such as blinking.

[0076] [Display flow of judgment results] When the operator loads a syringe after turning on the power of injection head 20, the reading unit of injection head 20 reads, for example, a product ID as liquid medicine information and sends it to simulator 40. Then, information acquisition unit 43 of simulator 40 acquires the liquid medicine information read by the reading unit. In addition, display control unit 48 reads out the manufacturer name, the product name based on the product ID, and the filling amount from storage unit 42 and displays them on the initial screen. Furthermore, information acquisition unit 43 stores the acquired product ID in storage unit 42 as liquid medicine information. Next, the operator selects a desired part from the silhouette image displayed on the initial screen and performs a touch operation. Then, as shown in FIG. 7, information acquisition unit 43 acquires information specifying the part selected by the operator as the selected part as part information and stores it in storage unit 42 (S701).

[0077] When the operator selects the region, the display control unit 48 displays an input screen (S702), and the operator inputs the subject information, the examination information, the target value, and the like. Then, the information acquisition unit 43 acquires each piece of information, such as the subject information, the examination information, and the target value, and temporarily stores it in the storage unit 42 (S703). The amount of iodine used in the examination information may be calculated and acquired by the information acquisition unit 43 based on the weight of the subject. Then, when the operator inputs the subject information and the like and a certain time has passed (YES in S704), the display control unit 48 displays a confirmation screen on the touch panel 26 (S705). On the other hand, until the certain time has passed (NO in S704), the display control unit 48 displays the input screen. The order of acquisition or input of the liquid medicine information, the examination information, the subject information, and the like can be changed as appropriate.

[0078] In parallel with the display of the confirmation screen, the prediction unit 46 starts a simulation of the change over time of the pixel values ​​(S706). That is, the prediction unit 46 starts the simulation when a certain time has passed since the operator inputted the subject information. Then, when the simulation ends, the prediction unit 46 stores the simulation result in the storage unit 42. In addition, the determination unit 47 executes a determination after the simulation ends (S707), and stores the determination result in the storage unit 42. Next, when the operator flicks the simulation start or display button 59, the display control unit 48 displays a simulation screen on the touch panel 26.

[0079] Here, the display control unit 48 refers to the judgment result by the judgment unit 47. Then, when the judgment unit 47 judges that the pixel value of the selected part is higher than the upper limit value (YES in S708), the display control unit 48 displays the first part image 61A and the first position image 64A on the simulation screen (S709). Also, when the judgment unit 47 judges that the pixel value of the selected part is lower than the lower limit value (YES in S710), the display control unit 48 displays the second part image 61B and the second position image 64B on the simulation screen (S711). Also, when the judgment unit 47 judges that the pixel value of the selected part is lower than the upper limit value and higher than the lower limit value (NO in S710), the display control unit 48 displays the third part image 61C on the simulation screen (S712). The display of each image completes the display of the judgment result. Thereafter, when the time during which the operator does not perform any operation reaches a certain time, the display control unit 48 displays the confirmation screen again.

[0080] The operator then checks the display contents of the confirmation screen, and if there are no changes, selects air check button 58. Alternatively, the start of injection may be restricted until the operator changes the settings and third site image 61C is displayed. For example, the display of air check button 58 may be restricted until third site image 61C is displayed. Then, display control unit 48 causes a start button to be displayed on the confirmation screen. This completes preparation for injection, and injection head 20 waits in an injection-enabled state. Alternatively, the operator may press a final confirmation button on operation unit 28 of injection head 20. Next, when the operator touches the start button, injection head 20 starts injection.

[0081] According to the invention of the first embodiment described above, the operator can determine whether or not a desired pixel value is obtained in a region selected as an imaging region. That is, the first image, the second image, or the third image is displayed on the simulation screen. Therefore, the operator can visually recognize whether or not the pixel value is within a desired range by the displayed image.

[0082] Although the present invention has been described above with reference to each embodiment, the present invention is not limited to the above embodiment. The present invention also includes inventions that have been modified without going against the present invention, and inventions equivalent to the present invention. In addition, each embodiment and each modified form can be appropriately combined without going against the present invention.

[0083] For example, the display control unit 48 may display the judgment result at a timing when an arbitrary time has elapsed since the start of injection on the simulation screen in response to an operation by the operator. As an example, the operator can move the instruction image 63 in the left-right direction in the figure along the axis. The judgment unit 47 compares the pixel value at the timing indicated in the instruction image 63 with the upper limit value and the lower limit value. Then, the judgment unit 47 judges whether the pixel value is higher than the upper limit value and judges whether the pixel value is lower than the lower limit value. Thereafter, the display control unit 48 displays the first image, the second image, or the third image on the simulation screen in response to the judgment result of the judgment unit 47.

[0084] At this time, the display control unit 48 may gradually change the display mode of the image when changing the first image, the second image, or the third image to another image. For example, when changing from the third image to the first image, the brightness of the third image may be gradually increased to change it to the first image. Also, when changing from the third image to the second image, the brightness of the third image may be gradually decreased to change it to the second image. Alternatively, the display control unit 48 may display a slider image on the axis line. In this case, the operator moves the slider image to display the first image, the second image, or the third image as a judgment result at any timing. In addition, the display control unit 48 may have a mode in which the image is displayed so that the shading of the image of each tissue changes according to the change over time in the pixel value of each tissue with reference to the simulation result.

[0085] Simulator 40 may also be mounted on an external computer that is connected by wire or wirelessly to at least one of imaging device 30 and injection head 20. In this case, simulator 40 transmits the simulation results to imaging device 30 or injection head 20. [Explanation of symbols]

[0086] 26: display unit, 40: simulator, 41: computer, 46: prediction unit, 47: determination unit, 48: display control unit, 61A: first image, 61B: second image, 61C: third image, 62: image showing length, 63: information showing imaging timing, 64A: first image, 64B: second image, PG: simulation program

Claims

1. a prediction unit that simulates pixel values ​​at a selected site when a contrast agent is injected according to a predetermined injection condition; a determination unit that determines whether the pixel value is higher than an upper limit value and determines whether the pixel value is lower than a lower limit value based on a simulation result by the prediction unit; A simulator comprising: a display control unit that causes a first image to be displayed on a display unit when the pixel value is higher than the upper limit value, and causes a second image having a display mode different from that of the first image to be displayed on the display unit when the pixel value is lower than the lower limit value.

2. The simulator of claim 1 , wherein the display control unit causes the display unit to display a third image having a display manner different from the first image and the second image when the pixel value is lower than the upper limit value and higher than the lower limit value.

3. The simulator according to claim 1 , wherein the display control unit displays the first image so as to have a higher brightness than the second image.

4. The simulator according to any one of claims 1 to 3, wherein the display control unit causes the display unit to display an image indicating the length of time during which the pixel value is maintained at a state lower than the upper limit value and higher than the lower limit value, the image being sized according to the length of the maintenance time.

5. The determination unit determines a timing during the maintenance time as an imaging timing, The simulator according to claim 4 , wherein the display control unit causes the display unit to display information indicating the image capture timing.

6. simulating pixel values ​​at the selected site when a contrast agent is injected according to a predetermined injection condition; determining whether the pixel value is higher than an upper limit value and whether the pixel value is lower than a lower limit value based on a simulation result; A method for controlling a simulator, which displays a first image when the pixel value is higher than the upper limit value, and displays a second image having a display manner different from that of the first image when the pixel value is lower than the lower limit value.

7. The simulator computer a prediction unit that simulates pixel values ​​at a selected site when a contrast agent is injected according to a predetermined injection condition; a determination unit that determines whether the pixel value is higher than an upper limit value and determines whether the pixel value is lower than a lower limit value based on a simulation result by the prediction unit; A simulation program that functions as a display control unit that displays a first image on a display unit when the pixel value is higher than the upper limit value, and displays a second image, having a display mode different from that of the first image, on the display unit when the pixel value is lower than the lower limit value.

Images