JP2021041019A - Simulator, simulation system, generating program, and generation method - Google Patents

Abstract

To reduce frequency of simulation and to shorten a generation time of a prediction injection protocol.SOLUTION: A simulator includes: a protocol acquisition part acquiring an injection protocol including a first phase and a second phase; a prediction part creating a time emphasis curve on the basis of the injection protocol; a target value acquisition part acquiring a target pixel value; a tissue information acquisition part acquiring an original pixel value of the tissue; and a determination part performing evaluation processing of the time emphasis curve, adjusting the injection protocol in accordance with a result of the evaluation processing, and generating a prediction injection protocol. The determination part calculates a first side normalized from a first side obtained by subtracting the original pixel value from the target pixel value, calculates a first bottom side normalized from a first bottom side obtained by subtracting from a second time when the prediction pixel value reaches the target pixel value a first time when the prediction pixel value is beyond the original pixel value, calculates a first angle made by the normalized first diagonal side and the normalized first bottom side, and determines whether or not the first angle is included in a prescribed range.SELECTED DRAWING: Figure 2

Description

The present invention relates to a simulator, a simulation system, a generation program, and a generation method for simulating to generate a predictive injection protocol using an injection protocol including a plurality of injection phases.

Patent Document 1 describes a simulator including a prediction unit for obtaining a prediction maintenance time by simulating a change over time in a pixel value of a tissue of a subject based on an injection protocol and an amount of contrast medium. When the predicted maintenance time is shorter than the target maintenance time of the target pixel value, this prediction unit resimulates the change over time when a larger amount of contrast medium is injected than the amount of contrast medium used in the simulation, and predicts the prediction. I'm asking for maintenance time again. In addition, when the predicted maintenance time is longer than the target maintenance time, the prediction unit resimulates the change over time when a smaller amount of contrast medium is injected than the amount of contrast medium used, and obtains the predicted maintenance time again. ..

FIG. 3 of Patent Document 2 discloses an injection protocol including two injection phases as a plurality of injection phases. In this injection protocol, the injection rate of the contrast agent is constant until a predetermined time elapses. Then, after a predetermined time has passed, the injection rate of the contrast medium decreases with the passage of time.

Japanese Unexamined Patent Publication No. 2019-013296 Japanese Patent No. 5117376

In the simulator described in Patent Document 1, many re-simulations in which the injection rate and the injection amount are adjusted are performed in order to obtain an injection protocol that reaches the target pixel value and satisfies the target maintenance time. Therefore, the simulation takes a long time, and it is difficult to obtain the injection protocol in a practical time (for example, several seconds). In particular, when an injection protocol including a plurality of injection phases as described in Patent Document 2 is used, the time required for simulation becomes longer.

The simulator according to one aspect of the present invention includes a protocol acquisition unit for acquiring a drug solution injection protocol including a first phase and a second phase following the first phase, and a subject tissue based on the injection protocol. A prediction unit that simulates the change over time of the contrast agent concentration to create a time-enhanced curve showing the change over time, a target value acquisition unit that acquires the target pixel value, and a tissue information acquisition that acquires the initial pixel value of the tissue. A unit and a determination unit that performs evaluation processing of the time emphasis curve and adjusts the injection protocol according to the result of the evaluation processing to generate a predictive injection protocol. The determination unit includes the target pixel value. The normalized first side is calculated from the first side obtained by subtracting the initial pixel value from, and the predicted pixel value is the initial pixel from the second time point when the simulated predicted pixel value reaches the target pixel value. The normalized first base is calculated from the first base obtained by subtracting the first time point exceeding the value, and the normalization in the first triangle including the normalized first side and the normalized first base is performed. The time emphasis curve is evaluated by calculating the first angle formed by the first oblique side and the normalized first base and determining whether or not the first angle is included in a predetermined range. It is characterized by that.

Further, the simulation system according to one aspect of the present invention is characterized by including an injection head for injecting a contrast medium and the simulator.

Further, the simulation system according to one aspect of the present invention is characterized by including an imaging device for imaging a subject and the simulator.

Further, the generation program according to one aspect of the present invention is a generation program that generates a predictive injection protocol for a chemical solution, and injects a chemical solution into a computer including a first phase and a second phase following the first phase. A protocol acquisition unit that acquires a protocol, a prediction unit that simulates a time-dependent change in the contrast agent concentration of the subject tissue based on the injection protocol, and creates a time-enhanced curve indicating the time-dependent change, and a target pixel value. The target value acquisition unit to be acquired, the tissue information acquisition unit to acquire the initial pixel value of the tissue, and the time emphasis curve are evaluated, and the injection protocol is adjusted according to the result of the evaluation process to make a prediction. It functions as a determination unit for generating an injection protocol, and the determination unit calculates a normalized first side from a first side obtained by subtracting the initial pixel value from the target pixel value, and simulates a predicted pixel. The normalized first base is calculated from the first base obtained by subtracting the first time when the predicted pixel value exceeds the initial pixel value from the second time when the value reaches the target pixel value, and the normalized first base is calculated. The first angle formed by the normalized first oblique side and the normalized first base in the first triangle including the first side and the normalized first base is calculated, and the first angle is predetermined. It is characterized in that the time emphasis curve is evaluated by determining whether or not it is included in the range.

The production method according to one aspect of the present invention is a method for generating a predictive injection protocol for a drug solution, which is obtained by acquiring an injection protocol for a drug solution including a first phase and a second phase following the first phase, and injecting the drug solution. Based on the protocol, the time course of the contrast agent concentration in the tissue of the subject is simulated, a time-enhanced curve showing the time change is created, a target pixel value is acquired, an initial pixel value of the tissue is acquired, and the above. When the time-enhanced curve is evaluated, the injection protocol is adjusted according to the result of the evaluation process to generate a predictive injection protocol, and the time-enhanced curve is evaluated, the initial target pixel value is used as the initial value. The normalized first side is calculated from the first side obtained by subtracting the pixel value, and the predicted pixel value exceeds the initial pixel value from the second time point when the simulated predicted pixel value reaches the target pixel value. The normalized first base is calculated from the first base obtained by subtracting the first time point, and the normalized first in the first triangle including the normalized first side and the normalized first base. The time-enhanced curve is evaluated by calculating a first angle formed by the oblique side and the normalized first base and determining whether or not the first angle is included in a predetermined range. And.

As a result, the number of simulations can be reduced and the generation time of the predictive injection protocol can be shortened.

Further features of the present invention will become apparent from the description of the following examples exemplified by reference to the accompanying drawings.

It is a schematic block diagram of a simulator. It is explanatory drawing of the outline of the time emphasis curve. It is a graph which shows the injection protocol. It is a flowchart of a simulation. It is a flowchart of 1st determination. It is a flowchart of the 2nd determination. It is a flowchart of time adjustment processing. It is a flowchart of a pixel value adjustment process. It is a schematic block diagram of a simulation system.

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 the components described in the following embodiments can be arbitrarily set and can be changed according to the configuration of the device to which the present invention is applied or various conditions. Further, unless otherwise specified, the scope of the present invention is not limited to the embodiments specifically described below.

Unless otherwise stated, the term contrast agent includes both the contrast agent alone and a chemical solution containing the contrast agent as well as other solvents and additives. Further, in the following, unless otherwise specified, the term pixel value refers to the CT value, the sum or average value of the CT values of the pixels included in the region of interest (ROI), or the interest in the imaged region being imaged. The SD value (standard deviation value) of the region is included. Further, the pixel value includes a value obtained by subtracting a value in an imaging site that is not contrast-enhanced (for example, a CT value of an imaging site in simple CT) from these values. The area of interest is preset or the user can select the area of interest.

As shown in FIG. 1, the simulator 20 that predicts the time-dependent change of the pixel value in the tissue of the subject includes a subject information acquisition unit 11 that acquires subject information about the subject that is the subject. This subject information includes, for example, iodine amount per body weight, gender, weight, height, body surface area, cardiac function, heart rate, stroke volume, cardiac output, hemoglobin amount, estimated glomerular filtration rate (eGFR), and the like. It includes creatinine level, age, lean body weight, body mass index, circulating blood volume, subject number (subject ID), history of subject's disease and side effects, subject name, date of birth, blood volume, and blood flow velocity.

The subject information acquisition unit 11 acquires the subject information input by the user via the touch panel 26 that functions as an input unit or an operation unit for the simulator 20. Further, the subject information acquisition unit 11 may acquire subject information from the storage unit 24 of the simulator 20 or the server S which is an external storage device. In this case, the simulator 20 and the server S function as a simulation system as a whole. Examples of the server S include a RIS (Radiology Information System), a PACS (Picture Archiving and Communication System), a HIS (Hospital Information System), an image inspection system, and an image creation workstation. Further, the subject information acquisition unit 11 may acquire subject information from the imaging device 3 or the injection device 2 (FIG. 9), which will be described later.

The server S is configured as one logical server S by combining server units as a plurality of computers. However, the server S may be configured by a single server unit. Alternatively, the server S may be logically configured by using cloud computing. Further, the server S is configured as a computer in which a processor that executes various arithmetic processes and operation controls according to a predetermined program, an internal memory required for the operation of the processor, and other peripheral devices are combined.

In addition, the simulator 20 includes a protocol acquisition unit 12 that acquires an injection protocol of a contrast medium including a plurality of phases. As an example, the protocol acquisition unit 12 acquires a standard injection protocol by generating it based on chemical solution information or the like acquired from the injection device 2. Further, the protocol acquisition unit 12 may acquire the injection protocol input by the user via the simulator 20. Further, the protocol acquisition unit 12 may acquire the injection protocol from the storage unit 24, the server S, or the injection device 2. The infusion protocol, by way of example, includes the infusion time and infusion rate of the drug solution, including a first phase and a second phase following the first phase. Further, the plurality of injection phases may be three or more phases. In the following, a case where an injection protocol including two injection phases is used will be described.

The injection protocol further includes an upper limit of injection rate and a lower limit of injection volume for each phase. The injection protocol may also include injection method, contrast injection location, injection volume, injection timing, contrast concentration, injection pressure, and acceleration of injection rate. In addition, the injection protocol includes contrast agent injection time and rate, saline injection time and injection rate, contrast agent boost injection presence / absence, injection rate increase / decrease, cross injection presence / absence, link speed setting presence / absence, and It may include information such as the volume of the injection tube. Cross injection means that the contrast medium is injected at a speed higher than the injection rate of physiological saline from the start of injection until a set time elapses, and then the contrast medium is injected so that the injection rate gradually decreases, and at the same time, the injection is performed. This is an injection method in which physiological saline is injected so that the rate gradually increases. The link speed setting is a setting for linking the injection speeds of the contrast medium and the physiological saline so that the injection speeds of the contrast medium and the physiological saline are the same.

The simulator 20 includes an organization information acquisition unit 13 that acquires the organization information of the subject input by the user via the touch panel 26. Specifically, the organization information acquisition unit 13 acquires the initial pixel value of the organization. In addition, the organization information may include other information of the target organization of the simulation. This target tissue includes, for example, blood vessels such as aorta and coronary arteries, heart (right ventricle and left ventricle), kidney, ureter, other organs and muscles. Further, the tissue information acquisition unit 13 may acquire tissue information from the storage unit 24, the server S, or the injection device 2.

Further, the simulator 20 includes a chemical solution information acquisition unit 14 for acquiring chemical solution information regarding the chemical solution. Specifically, the chemical solution information acquisition unit 14 acquires the iodine content from the reading unit built in the injection device 2. This reading unit reads the drug solution information from the data carrier attached to the syringe mounted on the injection head 21 (FIG. 9) described later. The data carrier is, for example, an RFID chip, an IC tag, or a barcode. Further, the chemical solution information acquisition unit 14 may acquire the chemical solution information input by the user via the touch panel 26. This chemical information includes, for example, iodine content, iodine amount per unit, viscosity, osmotic pressure ratio, contrast medium amount, physiological saline 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. Further, the drug solution information acquisition unit 14 may acquire the drug solution information from the storage unit 24, the server S, or the injection device 2.

Further, the simulator 20 includes a target value acquisition unit 15 for acquiring a target pixel value. The target value acquisition unit 15 can further acquire the target maintenance time. The user can input the target pixel value required for image interpretation of the target tissue and the desired target maintenance time for maintaining the target pixel value from the touch panel 26. Alternatively, the target value acquisition unit 15 may acquire at least one of the target pixel value and the target maintenance time from the storage unit 24, the server S, or the like.

Further, the simulator 20 includes a control unit 25 and a storage unit 24 that stores the control program PG1. The control unit 25 controls each unit of the simulator 20 according to the control program PG1 stored in the storage unit 24. Further, the control unit 25 includes a subject information acquisition unit 11, a protocol acquisition unit 12, an organization information acquisition unit 13, a chemical solution information acquisition unit 14, a target value acquisition unit 15, a prediction unit 16, and a determination unit 17. Then, the control unit 25 executes various processes corresponding to the generation program PG2 mounted on the storage unit 24, so that each unit is logically realized as various functions. Further, the control unit 25 also functions as a display control unit that displays an image on the touch panel 26 that functions as a display unit.

As an example, the control unit 25 has a processor (not shown). The processor is, for example, a CPU (Central Processing Unit) or an MPU (Micro-Processing Unit), and controls the entire simulator 20 based on the control program PG1 stored in the storage unit 24, and also controls various processes. Control. In the present embodiment, the CPU can execute various processing operations such as calculation, control, and discrimination according to the control program PG1 stored in the storage unit 24. Further, a touch panel 26 is connected to the control unit 25 as an input unit for inputting predetermined commands and data. The touch panel 26 also functions as a display unit that displays an input state, a setting state, a measurement result, and various information of the device. Further, the control unit 25 is 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 device such as a server on the Internet. Control can also be performed according to a program stored in the storage medium.

The storage unit 24 has a RAM (Random Access Memory), which is a system work memory for operating the control unit 25, a ROM (Read Only Memory) for storing a program or system software, or a hard disk drive. The storage unit 24 also stores a generation program PG2 that generates a predictive injection protocol for the contrast medium. The generation program PG2 causes the computer to function as a protocol acquisition unit 12, a prediction unit 16, a target value acquisition unit 15, an organization information acquisition unit 13, and a determination unit 17. Further, the generation program PG2 can be stored in a non-temporary recording medium that can be read by a computer.

Further, the simulator 20 simulates the time-dependent change of the contrast medium concentration in the tissue of the subject based on the acquired injection protocol, and creates a time enhancement curve (hereinafter referred to as TEC (Time Enhancement Curve)) showing the time-dependent change. The prediction unit 16 is provided. As an example, the prediction unit 16 receives iodine amount per body weight (mgI / kg), body weight (kg), and height (cm) as subject information from the subject information acquisition unit 11. Further, the prediction unit 16 acquires the injection time (sec) and the injection rate (mL / sec) of the contrast medium in the first and second phases as the injection protocol from the protocol acquisition unit 12. Further, the prediction unit 16 acquires the name of the target organization for simulation from the organization information acquisition unit 13. In addition, the prediction unit 16 acquires the iodine content (mgI / mL) as the drug solution information from the drug solution information acquisition unit 14. Then, the prediction unit 16 calculates the total iodine amount (mgI) from the iodine amount per body weight and the body weight of the subject. Further, the prediction unit 16 calculates the total injection amount (mL) from the total iodine amount (mgI) and the iodine content (mgI / mL). Then, the prediction unit 16 simulates the time-dependent change of the pixel value in the tissue of the subject. This simulation is performed based on subject information, injection protocol, and tissue information. After that, the prediction unit 16 stores the change in the pixel value for each time in the storage unit 24 to create a TEC of the target tissue.

For example, the prediction unit 16 predicts the time course of the contrast medium concentration of each tissue in order toward each of the upstream and downstream in the blood flow direction. Specifically, the prediction unit 16 obtains the change in the pixel value in the target tissue as a time function in order to simulate the change in the pixel value with time. As an example, the prediction unit 16 uses a differential equation as shown in Equation 1 below. Here, the concentration of the contrast medium flowing into the target tissue is C ₁ , the concentration of the contrast medium flowing out of the target tissue is C ₂ , the volume of the target tissue is V, and the blood flow per unit tissue in the target tissue (blood flow). Speed) is Q.

Further, the prediction unit 16 determines the exudation rate when the contrast medium permeates from the capillaries into the extracellular fluid cavity and extracellularly in order to obtain changes in pixel values in tissues other than the right ventricle, left ventricle, and blood vessels. Consider the rate of re-penetration when permeating from the fluid cavity into the capillaries. Therefore, the prediction unit 16 uses differential equations such as the following equations 2 and 3. Here, the volume of the extracellular fluid cavity is Vec, the concentration of the contrast medium in the extracellular fluid cavity is Cec, the volume of the capillaries is Viv, the concentration of the contrast medium in the capillaries is Civ, and the exudation rate is PS. _It is set to 1 and the re-staining speed is set to PS ₂ .

By solving the above differential equation, the elapsed time from the start of injection and the change in the pixel value (contrast agent concentration) can be obtained as a time function. Further, the prediction unit 16 may calculate the discharge amount of the contrast medium based on the predetermined discharge rate and simulate to reduce the discharge amount. When the simulation is completed, the prediction unit 16 sequentially stores the simulation results in the storage unit 24 to create a TEC of the target tissue. The simulation results include information on the hourly pixel values associated with the tissue. Further, the prediction unit 16 may use another known method as a systemic circulation simulation of the contrast medium.

Further, the simulator 20 is connected to the console 23 of the injection device 2, and the touch panel 26 functions as an input unit and a display unit of the simulator 20. For example, the touch panel 26 displays the simulation result as a display unit of the simulator 20. Further, the simulator 20 may be connected to a plurality of injection devices 2. Further, the prediction unit 16 may acquire other information used for simulation such as tube voltage from the injection device 2 or the image pickup device 3.

[Simulation overview]
The outline of the simulation will be described with reference to FIGS. 2 and 3. In the TEC shown in FIG. 2, the horizontal axis corresponds to the elapsed time (sec) from the start of injection, and the vertical axis corresponds to the pixel value (HU) of the target tissue. This TEC is a curve showing the time course of the contrast medium concentration in the tissue of the subject after the start of injection. Further, FIG. 2 shows the TEC before the normalization described later is performed on the first side C1, the first base B1, and the second side C2. Further, FIG. 3 shows, as an example of an injection protocol including a plurality of injection phases, a variable injection protocol in which injection is performed at a constant injection rate in the first phase and is injected so that the injection rate decreases with time in the second phase. Is shown. In the following, a case where the ascending aorta is selected as the target tissue for the simulation and the variable injection protocol is selected as the injection protocol used for the simulation will be described.

In the TEC shown in FIG. 2, the initial pixel value OV, which is the pixel value before imaging of the target tissue, is 50 HU, the target pixel value TV is 400 HU, and the peak predicted by the prediction unit 16 is the highest. The pixel value PV is 437 HU. Further, the first time point T1 in which the predicted pixel value exceeds the initial pixel value OV is 13.0 sec after the start of injection. The second time point T2 when the predicted pixel value reaches the target pixel value TV is 24.5 sec after the start of injection, and the third time point T3 when the predicted pixel value reaches the peak pixel value PV is 32.5 sec after the start of injection. is there. Further, the fourth time point T4 at which the target pixel value TV is reached after the predicted pixel value reaches the peak pixel value PV is 42.5 sec after the start of injection.

Further, FIG. 2 shows a first triangle including a first side C1 obtained by subtracting the initial pixel value OV from the target pixel value TV and a first base B1 obtained by subtracting the first time point T1 from the second time point T2. It shows the first hypotenuse A1 in D1. Further, FIG. 2 shows a second side C2 obtained by subtracting the target pixel value TV from the peak pixel value PV, and a second base B2 obtained by subtracting the second time point T2 from the third time point T3 (hereinafter, the first half maintenance time B2). The second hypotenuse A2 of the second triangle D2 including (also referred to as) is shown. Further, FIG. 2 shows a first angle θ1 formed by the first hypotenuse A1 and the first base B1, and a second angle θ2 formed by the second hypotenuse A2 and the second base B2. Further, FIG. 2 shows the latter half maintenance time B3 obtained by subtracting the third time point T3 from the fourth time point T4.

The injection protocol can be roughly evaluated by evaluating the first angle θ1 and the second angle θ2. Therefore, it can be inferred based on the TEC how the injection protocol should be adjusted to obtain the ideal TEC. By using this guess, the number of re-simulations can be reduced in simulations using an injection protocol that includes multiple injection phases.

In the standard injection protocol shown in FIG. 3, an injection rate of 3.42 mL / sec and an injection time of 2.9 sec are set in the first phase, and the start injection rate is gradually reduced from 3.42 mL / sec to the end injection rate of 2.36 mL / sec in the second phase. The injection rate gradient -0.034 and the injection time 26.9 sec are set. The phases included in the injection protocol include a phase in which the injection rate increases or decreases with the passage of time, a phase in which the injection rate is constant, a phase in which another drug solution such as physiological saline is injected at the same time, and a phase in which only other drug solutions are injected. There are phases and phases that combine these.

[simulation]
The simulation will be described with reference to FIGS. 4 to 8. When the simulation is started, the prediction unit 16 acquires various information. Specifically, the prediction unit 16 acquires a standard injection protocol as an injection protocol used for simulation from the protocol acquisition unit 12. As an example, the protocol acquisition unit 12 generates and acquires a standard injection protocol based on the chemical solution information acquired from the chemical solution information acquisition unit 14 and the subject information acquired from the subject information acquisition unit 11. Further, the prediction unit 16 acquires the target pixel value and the target maintenance time from the target value acquisition unit 15. Further, the prediction unit 16 acquires the initial pixel value OV of the organization from the organization information acquisition unit 13.

After that, the prediction unit 16 simulates the time-dependent change of the pixel value of the tissue of the subject according to the acquired injection protocol. Then, the prediction unit 16 creates a TEC of the organization from the simulation result (S401). Here, the prediction unit 16 may simulate only the pixel values of the tissues selected by the user, or may simulate the pixel values of a plurality of tissues. The TEC does not have to be created in the form of a curve, and may be data from which the TEC can be derived. For example, the TEC may be created in the form of a table showing changes in pixel values over time. Then, the determination unit 17 performs an evaluation process of the created TEC, adjusts the first injection protocol used in the first phase according to the result of the evaluation process, and generates a predictive injection protocol.

That is, the determination unit 17 evaluates the TEC by performing the first determination including the determination as to whether or not the first angle θ1 is included in the predetermined range as the evaluation process (S402). By this first determination, the injection protocol is adjusted to reach the target pixel value. Subsequently, the determination unit 17 re-evaluates the TEC by performing a second determination including a determination as to whether or not the second angle θ2 is included in the predetermined range as an evaluation process (S403).

After that, when the determination unit 17 needs to adjust the first phase of the injection protocol (YES in S404), the determination unit 17 adjusts the first phase according to the result of the evaluation process (S405). Specifically, when the adjustment flag of the first phase is set in the first determination, the determination unit 17 adjusts the first phase. Further, when the adjustment of the first phase is not necessary (NO in S404) and the adjustment of the second phase of the injection protocol is necessary (YES in S406), the determination unit 17 determines according to the result of the evaluation process. The second phase is adjusted (S407). Specifically, when the adjustment flag of the second phase is set in the second determination, the determination unit 17 adjusts the second phase.

Here, when the adjustment of the first phase is necessary, the determination unit 17 adjusts the first phase before adjusting the second phase even if the adjustment of the second phase is necessary. Specifically, when the adjustment flags of the first phase and the second phase are set, the determination unit 17 adjusts the first phase before adjusting the second phase. After that, when the adjustment flag of the second phase is set, the determination unit 17 adjusts the second phase. On the other hand, when the adjustment of the second phase is unnecessary (NO in S406), the determination unit 17 ends the evaluation process. However, the adjustment of the second phase may be performed at the same time as the adjustment of the first phase.

Then, the determination unit 17 stores the injection protocol last used in the simulation in the storage unit 24 as a predictive injection protocol. Alternatively, the determination unit 17 stores as a predictive injection protocol the protocol closest to the target value among the plurality of injection protocols determined through the first determination and the second determination that the adjustment of the second phase is unnecessary. It may be stored in the unit 24. For example, the determination unit 17 may store the target pixel value TV and the protocol for obtaining the predicted pixel value and the maintenance time closest to the target maintenance time in the storage unit 24 as the predicted injection protocol. Further, the determination unit 17 may store the protocol with the least amount of contrast medium used in the storage unit 24 as the predictive injection protocol throughout the first phase and the second phase.

When the injection amounts of the first phase and the second phase in the standard injection protocol are small, the determination unit 17 determines the total injection amount of the first phase and the total injection amount of the second phase before creating the TEC (S401). At least one of the above may be increased. If the injection amount is too small, it is highly likely that it is determined that the target pixel value TV is not reached. Therefore, the number of times the simulation is repeated can be reduced by increasing the injection amount by the determination unit 17 in advance.

[First judgment]
In the first determination, the determination unit 17 first determines whether or not the predicted pixel value simulated by the prediction unit 16 has reached the target pixel value TV (S501). Then, when the determination unit 17 determines that the target pixel value TV has not been reached (NO in S501), the determination unit 17 sets an adjustment flag to increase the total injection amount in the first phase (S502) and ends the first determination. After that, since the adjustment of the first phase is required (YES in S404), the determination unit 17 adjusts the first phase (S405). As an example, the determination unit 17 calculates the ratio of the peak pixel value PV to the target pixel value TV and multiplies the ratio by the injection speed of the first phase. For example, when the target pixel value TV is 400HU and the peak pixel value PV is 380HU, the ratio 1.05 (= 400HU / 380HU) is multiplied by the injection rate of the first phase of 3.42 mL / sec to adjust the injection. Calculate and replace the rate 3.59 mL / sec. Here, since the determination unit 17 does not change the injection time of the first phase, the total injection amount of the first phase increases. As a result, the predicted pixel value is greatly increased as compared with the injection protocol in which the target pixel value TV is not reached, so that the number of simulation repetitions can be reduced.

Alternatively, the determination unit 17 may lengthen the injection time of the first phase to increase the total injection amount of the first phase. Further, when the difference between the target pixel value TV and the peak pixel value PV is smaller than a predetermined value (50 HU as an example), the determination unit 17 is compared with the case where the difference is larger than the predetermined value at the time of adjustment. The increase in the injection amount may be reduced.

Next, when the determination unit 17 determines that the target pixel value TV has been reached (YES in S501), the determination unit 17 determines whether or not the injection speed of the first phase exceeds a preset predetermined speed. (S503). This predetermined speed may be set by the user as the upper limit speed at which injection is possible. As an example, the predetermined rate is 10 mL / sec or 7 mL / sec. Then, when the determination unit 17 determines that the predetermined speed is exceeded (YES in S503), the determination unit 17 sets an adjustment flag for reducing the injection speed in the first phase (S504), and ends the first determination. After that, since the adjustment of the first phase is required (YES in S404), the determination unit 17 adjusts the first phase (S405). As an example, the determination unit 17 reduces the injection speed of the first phase to a set predetermined speed. The determination of whether or not the predetermined speed is exceeded (S503) may be omitted if it is not necessary to set the upper limit speed.

Subsequently, when the determination unit 17 determines that the predetermined speed is not exceeded (NO in S503), the determination unit 17 determines whether or not the total injection amount in the first phase has reached a preset predetermined amount (S505). ). This predetermined amount is set as a lower limit amount that can be injected from the viewpoint of the capacity of the syringe mounted on the injection device 2. As an example, the prescribed amount is 10 mL. Then, when the determination unit 17 determines that the injection amount in the first phase is less than the predetermined amount (YES in S505), the determination unit 17 sets an adjustment flag to increase the total injection amount in the first phase (S506), and makes the first determination. To finish. After that, since the adjustment of the first phase is required (YES in S404), the determination unit 17 adjusts the first phase (S405). As an example, the determination unit 17 increases the total injection amount in the first phase to a predetermined amount. The total injection amount in the first phase can be calculated by multiplying the injection rate by the injection time. For example, when the injection rate is 3.59 mL / sec and the injection time is 2.9 sec, the total injection volume is 10.41 mL (= 3.59 mL / sec × 2.9 sec). The determination of whether or not the predetermined amount has been reached (S505) may be omitted if it is not necessary to set the lower limit amount.

Next, in order to determine whether or not the first angle θ1 is included in the predetermined range, the determination unit 17 uses the equation 4 from the first side C1 obtained by subtracting the initial pixel value OV from the target pixel value TV. The first side C1 (normalized value of the first side C1) normalized based on is calculated. Further, the determination unit 17 is the first base obtained by subtracting the first time point T1 in which the predicted pixel value exceeds the initial pixel value OV from the second time point T2 in which the predicted pixel value predicted by the prediction unit 16 reaches the target pixel value TV. From B1, the first base B1 (normalized value of the first base B1) normalized based on the equation 5 is calculated. Further, the determination unit 17 determines the first hypotenuse A1 (normalized value of the first hypotenuse A1) in the first triangle D1 including the normalized first side C1 and the normalized first base B1 based on the equation 6. ) And the normalized first base B1 form a first angle θ1 (normalized value of the first angle θ1).

In Equation 4, the normalized value of the first side C1 is obtained by subtracting the initial pixel value OV from the target pixel value TV and dividing by 1000 HU. Here, the reason why 1000HU is used is that when it exceeds 1000HU, it is presumed to be a pixel value indicating bone (calcium), and 1000HU can be adopted as a practical upper limit pixel value. Further, in the mathematical formula 5, the normalized value of the first base B1 is obtained by subtracting the first time point T1 from the second time point T2 and dividing by 40 seconds. Here, the reason why 40 sec is used is that 40 sec can be adopted as a practical upper limit time because it usually does not exceed 40 sec in the first phase.

In the example of FIG. 2, the constant velocity injection rate in the first phase is 3.42 mL / sec, the target pixel value TV is 400 HU, the initial pixel value OV is 50 HU, and the second time point T2 is 24.5 sec. The first time point T1 is 13.0 sec. Therefore, when these are substituted from Equation 4 to Equation 6, the normalized value of the first side C1 is 0.35 and the normalized value of the first base B1 is 0.29, so that the normalized value of the first angle θ1 is 50.4. It becomes the degree. Then, the determination unit 17 determines whether or not the first angle θ1 is included in the predetermined range (S507). Specifically, the determination unit 17 determines whether or not the first angle θ1 is equal to or greater than a predetermined upper limit angle. As an example, the upper limit angle is 70.0 degrees.

Then, when the determination unit 17 determines that the first angle θ1 is equal to or greater than the upper limit angle (YES in S507), the determination unit 17 sets an adjustment flag for reducing the injection speed in the first phase (S508), and ends the first determination. .. After that, since it is necessary to adjust the first phase according to the result of the evaluation process (YES in S404), the determination unit 17 adjusts the first phase so as to reduce the injection speed (S405). As a result, the rising angle of the first angle θ1 in TEC becomes small. As an example, the determination unit 17 reduces the injection rate by multiplying the injection rate of the first phase by a predetermined constant less than 1.

On the other hand, when it is determined that the first angle θ1 is less than the upper limit angle (NO in S507), the determination unit 17 determines whether or not the first angle θ1 is included in the predetermined range. Determines whether or not has reached a preset lower limit angle (S509). As an example, the lower limit angle is 35.0 degrees, more preferably 20.0 degrees. Then, when the determination unit 17 determines that the first angle θ1 is less than the lower limit angle (YES in S509), the determination unit 17 sets an adjustment flag for increasing the injection speed in the first phase (S510), and ends the first determination. .. After that, since the first phase needs to be adjusted according to the result of the evaluation process (YES in S404), the determination unit 17 adjusts the first phase (S405). As an example, the determination unit 17 calculates the ratio of the first angle θ1 to the lower limit angle, and multiplies the ratio by the injection speed of the first phase. For example, when the lower limit angle is 35 degrees and the first angle θ1 is 30 degrees, the determination unit 17 multiplies the ratio 1.17 (= 35 degrees / 30 degrees) by the injection rate of the first phase of 3.42 mL / sec. Then, the adjusted injection rate of 4.00 mL / sec is calculated. The determination of whether or not the lower limit angle has been reached may be omitted if it is not necessary to set the lower limit angle.

[Second judgment]
In the second determination, first, the determination unit 17 determines whether or not the portion where the peak pixel value PV exceeds the target pixel value TV is within a predetermined range with reference to the target pixel value TV (S601). As an example, this predetermined range is a range in which the ratio of the target pixel value TV to the portion where the peak pixel value PV exceeds the target pixel value TV, that is, the ratio exceeding the target pixel value TV is 0.1 (10%) or less. For example, when the peak pixel value PV is 437HU and the target pixel value TV is 400HU, the determination unit 17 calculates the ratio 0.09 (= (437HU-400HU) / 400HU). Then, the determination unit 17 determines whether or not the ratio exceeds 0.1. When the pixel value is not within the predetermined range, that is, when the ratio exceeding the target pixel value TV exceeds 0.1 (NO in S601), the determination unit 17 will be described later so that the exceeding portion is included in the predetermined range. Pixel value adjustment processing (S602) is performed. The predetermined range may be set by the user.

On the other hand, when the pixel value is within a predetermined range (YES in S601), the determination unit 17 determines whether or not the simulated predicted maintenance time is within the predetermined range with reference to the target maintenance time (S603). ). Specifically, the determination unit 17 calculates the predicted maintenance time by subtracting the second time point T2 from the fourth time point T4 that reaches the target pixel value TV after the predicted pixel value reaches the peak pixel value PV. As an example, the above-mentioned predetermined range is a range in which the ratio of the target maintenance time to the predicted maintenance time is 1 or more and 1.1 or less (100% or more and 110% or less). For example, when the fourth time point T4 is 42.5 sec and the second time point T2 is 24.5 sec, the predicted maintenance time is 18 sec (= 42.5 sec-24.5 sec). Then, when the target maintenance time is 18 sec, the determination unit 17 calculates a ratio 1 (= 18 sec / 18 sec) and determines whether or not the ratio is 1 or more and 1.1 or less. When the predicted maintenance time is not within the predetermined range (NO in S603), the determination unit 17 performs a time adjustment process (S604) described later so that the predicted maintenance time is within the predetermined range.

On the other hand, when the predicted maintenance time is within a predetermined range (YES in S603), the determination unit 17 determines whether or not the first half maintenance time B2 and the second half maintenance time B3 in the TEC are within the predetermined criteria, respectively. (S605). As an example, in the determination unit 17, the ratio of the first half maintenance time B2 to half of the predicted maintenance time and the ratio of the second half maintenance time B3 to half of the predicted maintenance time are 0.95 or more and 1.05 or less (95% or more and 105% or less), respectively. If it is within the range, it is judged to be within the predetermined standard. As an example, when the first half maintenance time B2 is 8 sec and the second half maintenance time B3 is 10 sec, the time corresponding to half of the predicted maintenance time is 9 sec. Then, the determination unit 17 calculates the ratio of the first half maintenance time B2 to half of the predicted maintenance time 1.12 (= 9sec / 8sec) and the ratio of the second half maintenance time B3 to half of the predicted maintenance time 0.9 (= 9sec / 10sec). Then, it is determined whether or not each ratio is 0.95 or more and 1.05 or less.

When the first half maintenance time B2 and the second half maintenance time B3 are within the predetermined criteria (YES in S605), the determination unit 17 ends the second determination. In this case, since the adjustment has already been made, the adjustment of the first phase is unnecessary (NO in S404), and the adjustment of the second phase is unnecessary (NO in S406). Therefore, the determination unit 17 stores the injection protocol that has undergone the second determination in the storage unit 24 as the prediction injection protocol, and displays the prediction result on the touch panel 26. Further, the determination unit 17 sends the injection protocol to the injection device 2, and the injection device 2 can inject the drug solution according to the injection protocol.

On the other hand, when at least one of the first half maintenance time B2 and the second half maintenance time B3 is not within a predetermined standard (NO in S605), the determination unit 17 adjusts the second injection protocol used in the second phase. Specifically, the determination unit 17 determines whether or not the first half maintenance time B2 is longer than the second half maintenance time B3 (S606). If the first half maintenance time B2 is longer (YES in S606), the determination unit 17 sets a flag to increase the injection time in the second phase (S607) and ends the second determination. After that, since adjustment of the second phase is required (YES in S406), the determination unit 17 adjusts the second phase (S407). For example, the determination unit 17 lengthens the injection time of the second phase by changing the end injection rate without changing the start injection rate of the second phase and the total injection amount of the second phase. Alternatively, the determination unit 17 may increase the injection time of the second phase by changing the inclination of the injection rate of the second phase.

On the other hand, when the first half maintenance time B2 is shorter than the second half maintenance time B3 (NO in S606), the determination unit 17 sets a flag to shorten the injection time in the second phase (S608) and ends the second determination. After that, since adjustment of the second phase is required (YES in S406), the determination unit 17 adjusts the second phase (S407). For example, the determination unit 17 shortens the injection time of the second phase by changing the end injection rate without changing the start injection rate of the second phase and the total injection amount of the second phase. Alternatively, the determination unit 17 may shorten the injection time of the second phase by changing the inclination of the injection rate of the second phase.

[Time adjustment process]
When the predicted maintenance time is not within the predetermined range (NO in S603), the determination unit 17 performs the time adjustment process shown in FIG. 7 so that the predicted maintenance time is within the predetermined range. Specifically, the determination unit 17 determines whether or not the predicted maintenance time exceeds the target maintenance time, which is larger than the predetermined reference (S701). As an example, the determination unit 17 determines whether or not the ratio of the target maintenance time to the predicted maintenance time exceeds 1.1. Then, when the predicted maintenance time greatly exceeds the target maintenance time (YES in S701), the determination unit 17 determines whether or not the first half maintenance time B2 and the second half maintenance time B3 are within the predetermined criteria, respectively. (S702). Since the processing of S702 is the same as the processing of S605, the description thereof will be omitted.

When each of the first half maintenance time B2 and the second half maintenance time B3 is within a predetermined standard (YES in S702), the determination unit 17 sets a flag to reduce the total injection amount in the second phase (S703) and adjusts the time. End the process. After that, since adjustment of the second phase is required (YES in S406), the determination unit 17 adjusts the second phase (S407). For example, the determination unit 17 reduces the total injection amount of the second phase by shortening the injection time of the second phase without changing the inclination of the injection rate of the second phase and the start injection rate.

On the other hand, when the first half maintenance time B2 and the second half maintenance time B3 are not within the predetermined criteria (NO in S702), the determination unit 17 determines whether the first half maintenance time B2 is longer than the second half maintenance time B3 (NO). S704). When the first half maintenance time B2 is shorter (NO in S704), the determination unit 17 sets a flag to shorten the injection time in the second phase (S705), and ends the time adjustment process. Since the processing of S705 is the same as the processing of S608, the description thereof will be omitted.

Further, in the time adjustment process, the determination unit 17 determines whether or not the second angle θ2 is included in the predetermined range. Therefore, the determination unit 17 calculates the second side C2 (normalized value of the second side C2) normalized from the second side C2 obtained by subtracting the target pixel value TV from the peak pixel value PV in the TEC. Further, the determination unit 17 calculates the second base B2 (normalized value of the second base B2) normalized from the second base B2 obtained by subtracting the second time point T2 from the third time point T3. Further, the determination unit 17 normalizes the second hypotenuse A2 (normalized value of the second hypotenuse A2) in the second triangle D2 including the normalized second side C2 and the normalized second base B2. The second angle θ2 (normalized value of the second angle θ2) formed by the second base B2 is calculated. Then, the determination unit 17 re-evaluates the TEC by determining whether or not the second angle θ2 is included in the predetermined range.

In Equation 7, the determination unit 17 obtains the normalized value of the second side C2 by subtracting the target pixel value TV from the peak pixel value PV and dividing by 1000 HU. Further, in the mathematical formula 5, the normalized value of the second base B2 is obtained by subtracting the second time point T2 from the third time point T3 and dividing by 40 seconds.

In the example of FIG. 2, the target pixel value TV is 400 HU and the peak pixel value PV is 437 HU. Therefore, when this is substituted into Equation 7, the normalized value of the second side C2 becomes 0.037. Further, the second time point T2 is 24.5 sec, and the third time point T3 is 32.5 sec. Therefore, when this is substituted into Equation 8, the normalized value of the second base B2 becomes 0.2. Therefore, when these are substituted into Equation 9, the normalized value of the second angle θ2 becomes 10.5 degrees.

Then, when the first half maintenance time B2 is longer (YES in S704), the determination unit 17 determines whether or not the normalized second angle θ2 is smaller than a predetermined predetermined angle (S706). This predetermined angle is, for example, 3 to 5 degrees. When the normalized second angle θ2 is smaller than the predetermined angle (YES in S706), the determination unit 17 sets a flag to reduce the total injection amount in the second phase (S707) and ends the time adjustment process. Since the processing of S707 is the same as the processing of S703, the description thereof will be omitted. When the normalized second angle θ2 is larger than the predetermined angle (NO in S706), the determination unit 17 sets a flag to lengthen the injection time in the second phase (S708), and ends the time adjustment process. Since the processing of S708 is the same as the processing of S607, the description thereof will be omitted.

Then, when the predicted maintenance time is large and does not exceed the target maintenance time (NO in S701), the predicted maintenance time is shorter than the target maintenance time. In this case, the determination unit 17 determines whether or not the first half maintenance time B2 and the second half maintenance time B3 are within the predetermined criteria (S709). The first half maintenance time B2 corresponds to the first half portion of the predicted maintenance time before reaching the peak pixel value PV. Further, the latter half maintenance time B3 corresponds to the latter half portion of the predicted maintenance time after reaching the peak pixel value PV. In the example of FIG. 2, the first half maintenance time B2 is 8.0 sec (= 32.5 sec-24.5 sec), and the second half maintenance time B3 is 10.0 sec (= 42.5 sec-32.5 sec). Since the processing of S709 is the same as the processing of S605, the description thereof will be omitted.

When both the first half maintenance time B2 and the second half maintenance time B3 are within a predetermined standard (YES in S709), the determination unit 17 sets a flag to increase the total injection amount in the second phase (S710) and sets the time. The adjustment process ends. After that, since adjustment of the second phase is required (YES in S406), the determination unit 17 adjusts the second phase (S407). For example, the determination unit 17 increases the total injection amount of the second phase by lengthening the injection time of the second phase without changing the inclination of the injection rate of the second phase and the start injection rate.

When at least one of the first half maintenance time B2 and the second half maintenance time B3 is not within the predetermined reference (NO in S709), the determination unit 17 determines whether the first half maintenance time B2 is longer than the second half maintenance time B3. (S711). When the first half maintenance time B2 is shorter (NO in S711), the determination unit 17 sets a flag to shorten the injection time in the second phase (S712), and ends the time adjustment process. Since the processing of S712 is the same as the processing of S608, the description thereof will be omitted. When the first half maintenance time B2 is longer (YES in S711), the determination unit 17 sets a flag to lengthen the injection time in the second phase (S713), and ends the time adjustment process. Since the process of S713 is the same as the process of S607, the description thereof will be omitted.

[Pixel value adjustment processing]
When the peak pixel value PV is not within the predetermined range (NO in S601), the determination unit 17 shows FIG. 8 so that the portion where the peak pixel value PV exceeds the target pixel value TV is included in the predetermined range. Pixel value adjustment processing is performed. First, the determination unit 17 determines whether or not the predicted maintenance time is within a predetermined range based on the target maintenance time (S801). As an example, this predetermined range is a range in which the ratio of the target maintenance time to the predicted maintenance time is 0.85 or more and 1.1 or less (85% or more and 110% or less). When the predicted maintenance time is within a predetermined range (YES in S801), the determination unit 17 determines whether or not the first half maintenance time B2 and the second half maintenance time B3 are within the predetermined criteria (S802). Since the processing of S802 is the same as the processing of S605, the description thereof will be omitted.

When the first half maintenance time B2 and the second half maintenance time B3 are within the predetermined criteria (YES in S802), the determination unit 17 sets a flag to reduce the injection speed in the first phase (S803) and adjusts the pixel value. End the process. Further, when the first half maintenance time B2 and the second half maintenance time B3 are not within the predetermined criteria (NO in S802), the determination unit 17 determines whether or not the first half maintenance time B2 is longer than the second half maintenance time B3 (NO). S804). When the first half maintenance time B2 is shorter than the second half maintenance time B3 (NO in S804), the determination unit 17 sets a flag to reduce the injection amount in the first phase (S805), and ends the pixel value adjustment process. After that, since the adjustment of the first phase is required (YES in S404), the determination unit 17 adjusts the first phase (S405). For example, the determination unit 17 reduces the total injection amount of the first phase by shortening the injection time of the first phase without changing the injection rate of the first phase. When the first half maintenance time B2 is longer (YES in S804), the determination unit 17 sets a flag to lengthen the injection time in the second phase (S806) and ends the pixel value adjustment process. Since the processing of S806 is the same as the processing of S607, the description thereof will be omitted.

When the predicted maintenance time is not within the predetermined range (NO in S801), the determination unit 17 determines whether or not the predicted maintenance time is larger than the predetermined reference and exceeds the target maintenance time (S807). As an example, the determination unit 17 determines whether or not the ratio of the target maintenance time to the predicted maintenance time exceeds 1.1. Then, when the predicted maintenance time is large and the target maintenance time is greatly exceeded (YES in S807), the determination unit 17 determines whether or not the first half maintenance time B2 and the second half maintenance time B3 are within the predetermined criteria, respectively. Judgment (S808). Since the processing of S808 is the same as the processing of S605, the description thereof will be omitted.

When the first half maintenance time B2 and the second half maintenance time B3 are within a predetermined standard (YES in S808), the determination unit 17 sets a flag to reduce the injection speed in the first phase (S809) and performs the pixel value adjustment process. finish. Further, when the first half maintenance time B2 and the second half maintenance time B3 are not within the predetermined criteria (NO in S808), the determination unit 17 determines whether or not the first half maintenance time B2 is longer than the second half maintenance time B3 (NO). S810). When the first half maintenance time B2 is shorter than the second half maintenance time B3 (NO in S810), the determination unit 17 sets a flag to reduce the injection speed in the first phase (S811) and ends the pixel value adjustment process. Since the processing of S809 and S811 is the same as the processing of S803 or S805, the description thereof will be omitted. When the first half maintenance time B2 is longer than the second half maintenance time B3 (YES in S810), the determination unit 17 sets a flag to reduce the total injection amount in the second phase (S812) and ends the time adjustment process. Since the process of S812 is the same as the process of S703, the description thereof will be omitted.

When the predicted maintenance time is larger than the predetermined standard and does not exceed the target maintenance time (NO in S807), the predicted maintenance time is larger than the predetermined standard and is less than the target maintenance time. For example, the ratio of the target maintenance time to the predicted maintenance time is less than 0.85. In this case, the determination unit 17 determines whether or not the ratio of the target maintenance time to the predicted maintenance time is lower than a predetermined ratio (S813). This predetermined ratio is 0.8 (80%) as an example. For example, when the target maintenance time is 20 sec and the maintenance time is 18 sec, the determination unit 17 calculates the ratio 0.9 (= 18 sec / 20 sec) and determines whether or not it is lower than 0.8. If it is lower than the predetermined ratio (YES in S813), the determination unit 17 sets a flag to increase the total injection amount in the second phase (S814) and ends the pixel value adjustment process. Since the process of S814 is the same as the process of S710, the description thereof will be omitted. On the other hand, when the ratio is higher than the predetermined ratio (NO in S813), the determination unit 17 sets a flag to reduce the total injection amount in the first phase (S815) and ends the pixel value adjustment process. Since the processing of S815 is the same as the processing of S803 or S805, the description thereof will be omitted.

The determination unit 17 may end the simulation when the number of times the simulation is repeated reaches the upper limit. As an example, when the first determination or the second determination exceeds 25 times, the determination unit 17 ends the simulation and causes the touch panel 26 to display that the upper limit number of times has been reached.

[Simulation system]
Subsequently, a simulation system including the simulator 20 (FIG. 1) with reference to FIG. 9, which is a schematic diagram of a simulation system 100 including an injection device 2 and an image pickup device 3 and a server S (external storage device) (not shown). 100 will be described. The simulator 20 is mounted on at least one of the imaging device 3 and the injection device 2.

As shown in FIG. 9, the simulation system 100 includes an injection device 2 for injecting a contrast medium, and a medical image pickup device 3 connected to the injection device 2 by wire or wirelessly to image a subject. Examples of the imaging device 3 include 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, and the like. There are various medical imaging devices such as an MR angio device, an ultrasonic diagnostic device, and a blood vessel imaging device. The CT apparatus will be described below.

The imaging device 3 includes an imaging unit 31 that images a subject according to an imaging plan, and a control device 32 that controls the entire imaging device 3. This imaging plan includes, for example, imaging site, effective tube voltage, model name, manufacturer name, imaging time, tube voltage, imaging range, rotation speed, helical pitch, exposure time, dose, and imaging method. .. Then, the control device 32 controls the imaging unit 31 so as to follow the imaging plan to image the subject. Further, the control device 32 can be connected to a simulator 20 (not shown). Alternatively, the simulator 20 may be built into the control device 32. Further, the control device 32 can communicate with the imaging unit 31, the injection device 2, and the server S (not shown) by wire or wirelessly.

The imaging unit 31 includes 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 captures a fluoroscopic image of the subject by exposing the subject to X-rays and back-projecting the inside of the subject based on the X-rays transmitted through the subject. Alternatively, the imaging unit 31 may image using radio waves or ultrasonic waves.

The image pickup apparatus 3 has a display 33 as a display unit. The display 33 is connected to the control device 32 and displays an input state, a setting state, an imaging result, and various information of the device. Alternatively, the control device 32 and the display 33 can be integrally configured. Further, the image pickup apparatus 3 has a user interface such as a keyboard as an input unit 34. The user can input the drug solution information, the injection protocol, the tissue information, the subject information and the target value from the input unit 34 to the image pickup apparatus 3.

The injection device 2 includes an injection head 21 that injects a contrast medium according to an injection protocol. Then, the injection device 2 injects a chemical solution filled in a syringe, for example, a physiological saline solution and various contrast agents into the subject. Further, the injection device 2 includes a stand 22 for holding the injection head 21 and a console 23 connected to the injection head 21 by wire or wirelessly.

The console 23 functions as a control device for controlling the injection head 21, and a simulator 20 (not shown) is connected to the console 23. Alternatively, the simulator 20 may be built into the console 23. Further, the simulator 20 may be connected to the server S of FIG. 1, and the server S may function as the simulator 20. The console 23 includes a touch panel 26 that functions as an input display unit, and can communicate with the injection head 21 and the image pickup device 3 by wire or wirelessly. The touch panel 26 can display the injection protocol, the input state of the device, the setting state, the injection result, and various information, and functions as an input unit and a display unit of the simulator 20. The injection device 2 may include a display as a display unit and a keyboard as an input unit instead of the touch panel 26.

Instead of the console 23, the injection device 2 has a control device connected to the injection head 21 and a display unit (for example, a touch panel display) connected to the control device and displaying the injection status of the chemical solution. May be good. In this case, the simulator 20 is connected to the control device. Further, the injection head 21 and the control device can be integrally configured with the stand 22. Further, a ceiling suspension member may be provided instead of the stand 22, and the injection head 21 may be suspended from the ceiling via the ceiling suspension member.

Further, the injection device 2 may have a remote control device (for example, a hand switch or a foot switch) for remotely controlling the injection head 21. This remote control device can remotely control the injection head 21 to start or stop injection. Further, the injection device 2 may have a power source or a battery. The power supply or battery can be provided in either the injection head 21 or the control device, and can be provided separately from these.

The injection head 21 includes a syringe holding portion on which a syringe filled with a chemical solution is mounted, and a drive mechanism for pushing out the chemical solution in the syringe according to an injection protocol. Further, the injection head 21 has an operation unit 212 for inputting the operation of the drive mechanism. The operation unit 212 is provided with, for example, a forward button of the drive mechanism, a reverse button of the drive mechanism, and a final confirmation button. Further, the injection head 21 may include a head display that displays injection conditions, injection status, device input status, setting status, and various injection results.

When the contrast medium is injected, an accessory such as an extension tube is connected to the tip of a syringe mounted on the injection head 21. Then, when the preparation for injection is completed, the user presses the final confirmation button on the operation unit 212. As a result, the injection head 21 stands by in a state where injection can be started. When the injection is started, the contrast medium extruded from the syringe is injected into the subject's body via the extension tube.

Further, the injection head 21 can be equipped with a prefilled syringe having a data carrier such as an RFID chip, an IC tag, or a barcode, and various syringes. The injection head 21 is provided with a reading unit (not shown) for reading the data carrier attached to the syringe. This data carrier stores drug solution information regarding the drug solution. Further, the injection head 21 may have three or more syringe holders, or may have only one syringe holder.

The injection device 2 can receive information from the server S and can also transmit the information to the server S. Further, the image pickup apparatus 3 can also receive information from the server S and can transmit the information to the server S. The inspection order is stored in the server S in advance. This inspection order includes subject information regarding the subject and inspection information regarding the inspection content. Further, the server S can store information on the imaging result such as image data transmitted from the imaging device 3 and information on the injection result transmitted from the injection device 2. An external image inspection system or an image creation workstation can also be used to operate the injection device 2 and the image pickup device 3.

The user can change the imaging plan according to the prediction result by the prediction unit 16. Further, the image pickup apparatus 3 may change the image pickup plan according to the prediction result by the prediction unit 16. Specifically, the image pickup apparatus 3 can change, for example, a tube voltage or a tube current so as to reach a target pixel value or a target maintenance time. The user can inject the contrast agent using the generated predictive injection protocol. The injection device 2 may also change, for example, the injection rate or injection time to match the predicted injection protocol generated.

According to the invention according to the embodiment described above, by adjusting the first phase before adjusting the second phase, the number of simulations can be reduced and the generation time of the predictive injection protocol can be shortened.

Although the present invention has been described above with reference to each embodiment, the present invention is not limited to the above-described embodiment. The present invention also includes inventions modified to the extent not contrary to the present invention, and inventions equivalent to the present invention. In addition, each embodiment and each modification can be appropriately combined as long as it does not contradict the present invention.

For example, the simulator 20 may be mounted on an external computer connected to at least one of the image pickup device 3 and the injection device 2 by wire or wirelessly. In this case, the simulator 20 transmits the simulation result and the optimum predictive injection protocol to the imaging device 3 and the injection device 2.

3: Imaging device 12: Protocol acquisition unit 13: Tissue information acquisition unit 15: Target value acquisition unit 16: Prediction unit 17: Judgment unit 20: Simulator 21: Injection head 100: Simulation system

Claims (12)

A protocol acquisition unit that acquires a drug solution injection protocol including a first phase and a second phase following the first phase, and a protocol acquisition unit.
Based on the injection protocol, a prediction unit that simulates the change over time in the contrast medium concentration of the tissue of the subject and creates a time-enhanced curve showing the change over time.
The target value acquisition unit that acquires the target pixel value, and
An organization information acquisition unit that acquires the initial pixel value of the organization, and
It is provided with a determination unit that performs evaluation processing of the time emphasis curve, adjusts the injection protocol according to the result of the evaluation processing, and generates a predictive injection protocol.
The determination unit calculates a normalized first side from the first side obtained by subtracting the initial pixel value from the target pixel value, and the simulated predicted pixel value reaches the target pixel value at a second time point. The normalized first base is calculated from the first base obtained by subtracting the first time point when the predicted pixel value exceeds the initial pixel value, and the normalized first side and the normalized first base are calculated. The first angle formed by the normalized first hypotenuse and the normalized first base in the first triangle including and is calculated, and it is determined whether or not the first angle is included in a predetermined range. A simulator that evaluates the time-enhanced curve by. The simulator according to claim 1, wherein when the first angle is equal to or greater than the upper limit angle, the determination unit adjusts the first injection protocol used in the first phase so as to reduce the injection rate. When the first angle is greater than or equal to the upper limit angle, the determination unit adjusts the first injection protocol used in the first phase to reduce the injection rate.
When the first angle is less than the upper limit angle, the determination unit determines whether or not the first angle is less than the lower limit angle, and when the first angle is less than the lower limit angle, the injection speed. The simulator according to claim 1, wherein the first injection protocol is adjusted so as to increase. The determination unit determines whether or not the portion of the time emphasis curve whose peak pixel value exceeds the target pixel value is within a predetermined range with reference to the target pixel value.
The invention according to any one of claims 1 to 3, wherein when the exceeding portion is not within the predetermined range, the determination unit performs pixel value adjustment processing so that the exceeding portion is included in the predetermined range. Simulator. The target value acquisition unit further acquires the target maintenance time, and
The determination unit calculates the predicted maintenance time by subtracting the second time point from the fourth time point when the predicted pixel value reaches the peak pixel value in the time emphasis curve and then reaches the target pixel value, and calculates the predicted maintenance time. Is within a predetermined range based on the target maintenance time.
The present invention according to any one of claims 1 to 4, wherein when the predicted maintenance time is not within a predetermined range, the determination unit performs a time adjustment process so that the predicted maintenance time is included in the predetermined range. Simulator. When the predicted maintenance time is within a predetermined range, the determination unit calculates the first half maintenance time by subtracting the second time point from the third time point when the predicted pixel value reaches the peak pixel value, and also calculates the first half maintenance time. The latter half maintenance time is calculated by subtracting the third time point from the fourth time point, and it is determined whether or not the first half maintenance time and the second half maintenance time are within the predetermined criteria.
The simulator according to claim 5, wherein the determination unit adjusts the second injection protocol used in the second phase when at least one of the first half maintenance time and the second half maintenance time is not within a predetermined standard. In the time adjustment process, the determination unit calculates a normalized second side from the second side obtained by subtracting the target pixel value from the peak pixel value, and subtracts the second time point from the third time point. The normalized second base is calculated from the obtained second base, and the normalized second hypotenuse and the normalized in the second triangle including the normalized second side and the normalized second base are calculated. The simulator according to claim 6, wherein the time-enhanced curve is evaluated by calculating a second angle formed by the second base and determining whether or not the second angle is included in a predetermined range. The determination unit adjusts the second injection protocol so as to reduce the total injection amount when the second angle is smaller than the predetermined angle, and lengthens the injection time when the second angle is larger than the predetermined angle. 7. The simulator according to claim 7, wherein the second injection protocol is adjusted. An injection head that injects contrast medium and
A simulation system including the simulator according to any one of claims 1 to 8. An imaging device that captures the subject and
A simulation system including the simulator according to any one of claims 1 to 8. A generator that generates a predictive infusion protocol for chemicals,
A protocol acquisition unit that acquires a drug solution injection protocol including a first phase and a second phase following the first phase, and a protocol acquisition unit.
Based on the injection protocol, a prediction unit that simulates the change over time in the contrast medium concentration of the tissue of the subject and creates a time-enhanced curve showing the change over time.
The target value acquisition unit that acquires the target pixel value, and
An organization information acquisition unit that acquires the initial pixel value of the organization, and
The time-enhanced curve is evaluated, and the injection protocol is adjusted according to the result of the evaluation process to function as a determination unit for generating a predictive injection protocol.
The determination unit calculates a normalized first side from the first side obtained by subtracting the initial pixel value from the target pixel value, and the simulated predicted pixel value reaches the target pixel value at a second time point. The normalized first base is calculated from the first base obtained by subtracting the first time point when the predicted pixel value exceeds the initial pixel value, and the normalized first side and the normalized first base are calculated. To calculate the first angle formed by the normalized first hypotenuse and the normalized first base in the first triangle including and, and determine whether or not the first angle is included in a predetermined range. A generation program that evaluates the time-enhanced curve by. A method for generating a predictive injection protocol for chemicals.
Obtained a drug solution infusion protocol that includes a first phase and a second phase following the first phase.
Based on the injection protocol, the time-dependent change in the contrast medium concentration in the tissue of the subject is simulated to create a time-enhanced curve showing the time-dependent change.
Get the target pixel value and
Obtain the initial pixel value of the structure and
The time-enhanced curve is evaluated, and the injection protocol is adjusted according to the result of the evaluation process to generate a predictive injection protocol.
When evaluating the time emphasis curve, the normalized first side is calculated from the first side obtained by subtracting the initial pixel value from the target pixel value, and the simulated predicted pixel value is the target pixel. The normalized first base is calculated from the first base obtained by subtracting the first time when the predicted pixel value exceeds the initial pixel value from the second time when the value is reached, and the normalized first side and the above. Whether the first angle formed by the normalized first hypotenuse and the normalized first base in the first triangle including the normalized first base is calculated and the first angle is included in the predetermined range. A generation method that evaluates the time-enhanced curve by determining whether or not.

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