Medical information processing device, medical information processing program, medical information processing system, and medical information processing method

Abstract

To provide an index capable of evaluating resistance in a capillary vessel.SOLUTION: According to an embodiment, a medical information processing device includes an acquisition part and a calculation part. The acquisition part acquires blood vessel blood flow in a coronary artery, and myocardial blood flow in a cardiac muscle region to which blood is supplied by the coronary artery. The calculation part combines the blood vessel blood flow and the myocardial blood flow to calculate an index showing a capillary vessel resistance amount in the capillary vessel that supplies blood to the cardiac muscle region.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] An embodiment of the present invention relates to a medical information processing device, a medical information processing program, and a medical information processing system. [Background technology]

[0002] Conventionally, it has been known that when evaluating the state of myocardial ischemia, it is important to evaluate the vascular resistance of the capillaries in the myocardium (microcirculatory resistance) in addition to the blood flow rate in the coronary artery and the blood flow rate in the myocardium. Here, a method for evaluating microcirculatory resistance is known in which a laser beam is applied to the fingertip or the like to evaluate the blood flow in the capillaries of the finger or the like. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-039448 A Summary of the Invention [Problem to be solved by the invention]

[0004] The problem to be solved by the present invention is to provide an indicator capable of evaluating the resistance in capillaries. [Means for solving the problem]

[0005] A medical image processing apparatus according to an embodiment includes an acquisition unit and a calculation unit. The acquisition unit acquires a vascular blood flow rate in a coronary artery and a myocardial blood flow rate in a myocardial region to which blood is supplied by the coronary artery. The calculation unit combines the vascular blood flow rate and the myocardial blood flow rate to calculate an index indicating a capillary resistance in a capillary that supplies blood to the myocardial region. [Brief description of the drawings]

[0006] [Figure 1]FIG. 1 is a diagram showing an example of the configuration of a medical information processing apparatus according to the first embodiment. [Diagram 2] FIG. 2 is a diagram for explaining an example of calculation of a capillary resistance index by the medical information processing apparatus according to the first embodiment. [Diagram 3] FIG. 3 is a diagram for explaining an example of calculation of the capillary resistance index by the medical information processing apparatus according to the first embodiment. [Figure 4] FIG. 4 is a diagram for explaining an example of calculation of the capillary resistance index by the medical information processing apparatus according to the first embodiment. [Figure 5A] FIG. 5A is a diagram for explaining an example of calculation of a capillary resistance index by the medical information processing apparatus according to the first embodiment. [Figure 5B] FIG. 5B is a diagram for explaining an example of calculation of the capillary resistance index by the medical information processing apparatus according to the first embodiment. [Figure 6] FIG. 6 is a diagram showing an example of a display form of the capillary resistance index according to the first embodiment. [Figure 7A] FIG. 7A is a diagram showing an example of a display form of a capillary resistance index according to the first embodiment. [Figure 7B] FIG. 7B is a diagram showing an example of a display form of the capillary resistance index according to the first embodiment. [Figure 8A] FIG. 8A is a diagram showing an example of a display form of the capillary resistance index according to the first embodiment. [Figure 8B] FIG. 8B is a diagram showing an example of a display form of the capillary resistance index according to the first embodiment. [Figure 9] FIG. 9 is a diagram showing an example of a display form of the capillary resistance index according to the first embodiment. [Figure 10] FIG. 10 is a diagram showing an example of a display form of the capillary resistance index according to the first embodiment. [Figure 11] FIG. 11 is a diagram showing an example of a display form of the capillary resistance index according to the first embodiment. [Figure 12]FIG. 12 is a diagram showing an example of a display form of the capillary resistance index according to the first embodiment. [Figure 13] FIG. 13 is a diagram showing an example of a display form of the capillary resistance index according to the first embodiment. [Figure 14] FIG. 14 is a diagram showing an example of a display form of the capillary resistance index according to the first embodiment. [Figure 15] FIG. 15 is a diagram showing an example of a display form of the capillary resistance index according to the first embodiment. [Figure 16] FIG. 16 is a diagram showing an example of a display form of the capillary resistance index according to the first embodiment. [Figure 17] FIG. 17 is a diagram for explaining an example of a determination criterion for determining a treatment plan according to the first embodiment. [Figure 18] FIG. 18 is a flowchart showing a processing procedure by the medical image processing apparatus according to the first embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Hereinafter, embodiments of the medical information processing device, the medical information processing program, and the medical information processing system according to the present application will be described in detail with reference to the accompanying drawings. Note that the medical information processing device, the medical information processing program, and the medical information processing system according to the present application are not limited to the embodiments shown below.

[0008] (First embodiment) Fig. 1 is a diagram showing an example of the configuration of a medical information processing device 300 according to the first embodiment. As shown in Fig. 1, the medical information processing device 300 according to the first embodiment is connected to a medical image diagnostic device 100 and a server device 200 via a network 400. Note that the example shown in Fig. 1 is merely an example, and various other devices (for example, a terminal device, etc.) may be connected to the network 400.

[0009] The medical image diagnostic apparatus 100 is an X-ray diagnostic apparatus, an X-ray CT (Computed Tomography) apparatus, an MRI (Magnetic Resonance Imaging) apparatus, an ultrasound diagnostic apparatus, a SPECT (Single Photon Emission Computed Tomography) apparatus, a PET (Positron Emission computed Tomography) apparatus, a SPECT-CT apparatus in which a SPECT apparatus and an X-ray CT apparatus are integrated, a PET-CT apparatus in which a PET apparatus and an X-ray CT apparatus are integrated, or a group of these apparatuses, etc. The medical image diagnostic apparatus 100 according to the first embodiment is capable of generating three-dimensional medical image data (volume data).

[0010] Here, the medical image diagnostic device 100 collects medical image data capable of quantifying the blood flow rate of the coronary artery or the myocardium. For example, the X-ray CT device, which is the medical image diagnostic device 100, rotates an X-ray tube and an X-ray detector around the heart of a subject to which a contrast agent has been administered, detects X-rays that have passed through the subject, and collects projection data. Then, the X-ray CT device generates time-series three-dimensional CT image data (volume data) based on the collected projection data. As an example, the X-ray CT device collects coronary angiography CT image data for calculating the blood flow rate of the coronary artery by fluid analysis, and myocardial contrast CT image data for calculating the blood flow rate of the myocardium by perfusion analysis.

[0011] Then, in response to a request from the medical information processing device 300, the medical image diagnostic device 100 transmits the collected medical image data to the medical information processing device 300. In addition, the medical image diagnostic device 100 can also transmit the results of various analyses performed on the collected medical image data to the medical information processing device 300.

[0012] The server device 200 is a device that stores medical image data collected by a medical image diagnostic device (e.g., CT image data and CT images collected by an X-ray CT device, etc.) and various types of test information (e.g., information on intravascular pressure measured by a pressure wire, etc.), and performs various types of image processing on the medical image data. Here, the server device 200 stores the medical image data and various types of test information acquired from the medical image diagnostic device 100 via the network 400 in a memory circuit provided inside or outside the device. Then, in response to a request from the medical information processing device 300, the server device 200 transmits the medical image data and various types of test information stored in the memory circuit to the medical information processing device 300.

[0013] The medical information processing device 300 acquires medical image data from the medical image diagnostic device 100 and the server device 200 via the network 400, and processes the acquired image data. The medical information processing device 300 also acquires various types of examination information from the server device 200 via the network 400, and executes various processes using the acquired examination information. For example, the medical information processing device 300 is realized by a computer device such as a workstation.

[0014] For example, as shown in FIG. 1, a medical information processing device 300 includes a communication interface 310, a memory circuitry 320, an input interface 330, a display 340, and a processing circuitry 350.

[0015] The communication interface 310 is connected to the processing circuitry 350, and controls the transmission and communication of various data between the medical image diagnostic apparatus 100 or the server apparatus 200 connected via the network 400. For example, the communication interface 310 is realized by a network card, a network adapter, a NIC (Network Interface Controller), etc. As an example, the communication interface 310 receives medical image data and examination information from the medical image diagnostic apparatus 100 or the server apparatus 200, and outputs the received medical image data and examination information to the processing circuitry 350.

[0016] The memory circuitry 320 is connected to the processing circuitry 350 and stores various data. The memory circuitry 320 also stores various information used in the processing of the processing circuitry 350, processing results by the processing circuitry 350, various programs that the processing circuitry 350 reads and executes to realize various functions, and the like. For example, the memory circuitry 320 is realized by a semiconductor memory element such as a RAM (Random Access Memory) or a flash memory, a hard disk, an optical disk, and the like. In this embodiment, the memory circuitry 320 stores medical image data, examination information, and the like received from the medical image diagnostic apparatus 100 or the server apparatus 200.

[0017] The input interface 330 is connected to the processing circuit 350, and converts an input operation received from an operator into an electrical signal and outputs the electrical signal to the processing circuit 350. In this specification, the input interface 330 is not limited to an interface having physical operation parts such as a mouse and a keyboard. For example, an example of the input interface also includes an electrical signal processing circuit that receives an electrical signal corresponding to an input operation from an external input device provided separately from the device and outputs the electrical signal to a control circuit.

[0018] The display 340 is connected to the processing circuit 350 and displays various information and images output from the processing circuit 350. For example, the display 340 is realized by a liquid crystal monitor, a CRT (Cathode Ray Tube) monitor, a touch panel, etc. For example, the display 340 displays a GUI (Graphical User Interface) for receiving instructions from an operator, various display images, and various processing results by the processing circuit 350.

[0019] The processing circuitry 350 controls each component of the medical information processing device 300 in response to an input operation received from an operator via the input interface 330. For example, the processing circuitry 350 is realized by a processor. In this embodiment, the processing circuitry 350 stores medical image data, examination information, and the like output from the communication interface 310 in the storage circuitry 320. In addition, the processing circuitry 350 reads out the medical image data and examination information from the storage circuitry 320, executes various processes, and displays the processing results on the display 340.

[0020] With such a configuration, the medical information processing device 300 according to the present embodiment can provide an index for evaluating the resistance in the capillaries. Specifically, the medical information processing device 300 uses the vascular blood flow rate in the coronary artery and the myocardial blood flow rate in the myocardium to calculate a capillary resistance index for evaluating the resistance (microcirculatory resistance) in the capillaries that supply the blood flowing in from the coronary artery to the myocardium.

[0021] 1, the processing circuit 350 according to this embodiment executes a control function 351, an acquisition function 352, an image generation function 353, a calculation function 354, and a determination function 355. Here, the control function 351 is an example of a display control unit. The acquisition function 352 is an example of an acquisition unit. The calculation function 354 is an example of a calculation unit.

[0022] The control function 351 executes the overall control of the medical information processing device 300. Specifically, the control function 351 controls to execute processes according to various requests input via the input interface 330. For example, the control function 351 controls transmission and reception of medical image data and the like via the communication interface 310, storage of information in the memory circuitry 320, display of information (for example, a display image and an analysis result) on the display 340, and the like.

[0023] The acquisition function 352 acquires the vascular blood flow rate in the coronary artery and the myocardial blood flow rate in the myocardial region to which blood is supplied by the coronary artery. Specifically, the acquisition function 352 acquires the vascular blood flow rate in the coronary artery and the myocardial blood flow rate in the myocardial region to which blood is supplied by the coronary artery based on the medical image data and examination information acquired from the medical image diagnostic device 100 and the server device 200.

[0024] For example, the acquisition function 352 acquires the vascular blood flow rate in the coronary artery by performing fluid analysis on the coronary angiography CT image data acquired from the X-ray CT device, which is the medical image diagnostic device 100, or the server device 200. In addition to acquiring the vascular blood flow rate by fluid analysis, the acquisition function 352 can also acquire the vascular blood flow rate in the coronary artery by using FFR (Fractional Flow Reserve) measured by a pressure wire, instantaneous FFR, fluid analysis on the coronary angiography MR image data, etc. Hereinafter, an example will be described in which the vascular blood flow rate in the coronary artery is acquired by performing fluid analysis on the coronary angiography CT image data.

[0025] Incidentally, FFR and instantaneous FFR are indexes for estimating the degree of obstruction of blood flow, and are defined as the ratio of blood flow rate on the branching side of blood vessels to blood flow rate on the peripheral side. Here, in actual measurement of FFR, the relationship between blood flow rate and pressure in blood vessels is made proportional, and blood flow rate is replaced with pressure for measurement. For example, in measurement of FFR, adenosine is administered to create a maximum congestion state (stress state) to make the relationship between blood flow rate and pressure in blood vessels proportional, and the blood flow rate defining FFR is replaced with pressure. Also, for example, in measurement of instantaneous FFR, adenosine is not administered, and a time phase in which the relationship between blood flow rate and pressure in blood vessels is proportional in a resting state is used, thereby replacing the blood flow rate defining instantaneous FFR with pressure. Therefore, the acquisition function 352 acquires the blood flow rate in the coronary artery by converting the pressure value measured by the pressure wire into the blood flow rate value.

[0026] When performing fluid analysis based on coronary angiography CT image data to obtain vascular blood flow, the acquisition function 352 reads out coronary angiography CT image data of multiple time phases collected over time from the memory circuitry 320, and performs image processing on the read out coronary angiography CT image data of multiple time phases to extract time-series vascular shape data.

[0027] Here, the acquiring function 352 sets a target region for calculating an index value in a blood vessel region included in the coronary angiography CT image data. Specifically, the acquiring function 352 sets the target region in the blood vessel region by an instruction from an operator via the input interface 330 or by image processing. Details of the setting of the target region will be described later. Then, the acquiring function 352 extracts, from the coronary angiography CT image data, for example, the center line of the blood vessel (coordinate information of the center line), the cross-sectional area of ​​the blood vessel and the lumen in a cross section perpendicular to the center line, the distance from the center line to the inner wall and the distance from the center line to the outer wall in the cylindrical direction in a cross section perpendicular to the center line, etc.

[0028] Furthermore, the acquisition function 352 sets analysis conditions for the fluid analysis. Specifically, the acquisition function 352 sets the physical property values ​​of blood, the conditions for the iterative calculation, the initial values ​​of the analysis, and the like, as the analysis conditions. For example, the acquisition function 352 sets the viscosity and density of blood as the physical property values ​​of blood. Furthermore, the acquisition function 352 sets the maximum number of iterations in the iterative calculation, the relaxation coefficient, the allowable value of the residual, and the like, as the conditions for the iterative calculation. Furthermore, the acquisition function 352 sets the initial values ​​of the blood flow rate, pressure, fluid resistance, and pressure boundary, and the like, as the initial values ​​of the analysis. Note that the various values ​​used by the acquisition function 352 may be built into the system in advance, or may be interactively defined by the operator.

[0029] The acquisition function 352 then calculates index values ​​related to blood flow in the blood vessels by fluid analysis using the coronary angiography CT image data. Specifically, the acquisition function 352 executes fluid analysis using blood vessel shape data and analysis conditions to calculate index values ​​related to blood flow in the target region of the blood vessel. For example, the acquisition function 352 calculates index values ​​such as pressure, blood flow rate, blood flow velocity, vector, and shear stress for each predetermined position of the blood vessel based on blood vessel shape data such as the contours of the lumen and outer wall of the blood vessel, the cross-sectional area and core line of the blood vessel, and setting conditions such as the physical properties of blood, the conditions of iterative calculation, and the initial values ​​of the analysis. This allows the acquisition function 352 to acquire the blood flow rate for each position of the coronary artery.

[0030] Also, for example, the acquisition function 352 acquires the myocardial blood flow in the myocardium by performing perfusion analysis on the myocardial contrast CT image data acquired from the X-ray CT device, which is the medical image diagnostic device 100, or the server device 200. Note that the acquisition function 352 can acquire the myocardial blood flow in the myocardium by using myocardial scintigraphy using a SPECT device, quantification of the myocardial blood flow using a PET device, perfusion analysis on myocardial contrast MR image data, etc., in addition to acquiring the myocardial blood flow by perfusion analysis based on myocardial contrast CT image data. Hereinafter, an example will be described in which the myocardial blood flow in the myocardium is acquired by performing perfusion analysis on myocardial contrast CT image data.

[0031] When performing perfusion analysis based on myocardial contrast CT image data to obtain myocardial blood flow, the acquisition function 352 reads out myocardial contrast CT image data of multiple time phases collected over time during a period of multiple heartbeats from the storage circuitry 320, and performs image processing on the read out myocardial contrast CT image data of multiple time phases to calculate myocardial blood flow. For example, the acquisition function 352 calculates a TDC (Time Density Curve) for each pixel included in the left ventricular cavity (or aorta) and myocardium based on the myocardial contrast CT image data of multiple time phases collected over time during a period of multiple heartbeats. Then, the acquisition function 352 calculates the myocardial blood flow for each pixel of the myocardium based on the correspondence of the calculated TDC (Time Density Curve) for each pixel of the myocardium to the TDC (Time Density Curve) in the left ventricular cavity (or aorta). This allows the acquisition function 352 to obtain the blood flow for each position of the myocardium. The acquisition function 352 can also calculate the average value of the myocardial blood flow of a pixel group included in a predetermined region of the myocardium as the myocardial blood flow in the predetermined region.

[0032] As described above, the acquisition function 352 can calculate the vascular blood flow rate and the myocardial blood flow rate using the CT image data, thereby acquiring the vascular blood flow rate for each coronary artery position and the myocardial blood flow rate for each myocardial position. Here, the acquisition function 352 acquires the vascular blood flow rate and the myocardial blood flow rate at the position designated by the operator. Specifically, the acquisition function 352 acquires the vascular blood flow rate at the coronary artery position and the myocardial blood flow rate at the myocardial region corresponding to the target region for calculating the capillary resistance index. For example, the acquisition function 352 acquires the vascular blood flow rate and the myocardial blood flow rate at the corresponding position, for example, the terminal region of the coronary artery where stenosis is found, the myocardial region where ischemia is found, or the myocardial region that is the subject of medical treatment, as the target region for calculating the capillary resistance index.

[0033] As an example, the acquisition function 352 acquires the vascular blood flow rate in a coronary artery selected by the operator from among the coronary arteries included in the display image generated by the image generation function 353. Then, the acquisition function 352 identifies a myocardial region to which blood is supplied by the selected coronary artery, and acquires the myocardial blood flow rate in the identified myocardial region. Here, the operator can also specify a position in the coronary artery from which the vascular blood flow rate is to be acquired. That is, the operator can select the coronary artery from which the vascular blood flow rate is to be acquired, and further specify a position in the selected blood vessel from which the vascular blood flow rate is to be calculated.

[0034] If the position for acquiring the blood vessel blood flow rate is not specified (if only the coronary artery is selected), the acquiring function 352 may calculate the blood vessel blood flow rate at the branch point of the selected coronary artery. The controlled area of ​​the selected coronary artery is specified by, for example, the Voronoi method. That is, the acquiring function 352 specifies the controlled area of ​​the selected coronary artery by performing area expansion based on the shape of the selected coronary artery.

[0035] Also, for example, when a myocardial region is specified by the operator, the acquisition function 352 first identifies the coronary artery that supplies blood to the myocardial region specified by the operator. For example, the acquisition function 352 identifies the coronary artery that supplies blood to the specified myocardial region based on the morphological positional relationship between the coronary artery and the myocardium. Here, the acquisition function 352 can further identify the range of the coronary artery that supplies blood to the specified myocardial region. Then, the acquisition function 352 further identifies the control region of the selected coronary artery by performing region expansion based on the shape of the identified coronary artery, and acquires the myocardial blood flow in the identified control region.

[0036] When the coronary artery that supplies blood to the designated myocardial region is specified, the acquisition function 352 calculates, for example, the blood vessel blood flow rate at the branching point of the specified coronary artery. When the range of the coronary artery that supplies blood to the designated myocardial region is further specified, the acquisition function 352 calculates, for example, the blood vessel blood flow rate at the end on the branching point side in the range of the specified coronary artery.

[0037] The image generating function 353 reads out medical image data stored by the storage circuitry 320, and generates a display image from the read out medical image data. For example, the image generating function 353 reads out CT image data, and performs various image processing on the read out CT image data to generate a display image showing the entire heart, coronary arteries, and partial myocardial regions. As an example, the image generating function 353 performs image processing on the CT image data to generate a volume rendering image, a CPR (Curved Multi Planar Reconstruction) image, an MPR (Multi Planar Reconstruction) image, an SPR (Stretched Multi Planar Reconstruction) image, a polar map, and the like.

[0038] Furthermore, the image generating function 353 generates display information using test results such as vascular blood flow, myocardial blood flow, and FFR acquired by the acquiring function 352, and the capillary resistance index calculated by the calculating function 354. For example, the image generating function 353 generates a perfusion image showing the myocardial blood flow, a graph showing the capillary resistance index, and the like.

[0039] The calculation function 354 combines the vascular blood flow rate and the myocardial blood flow rate to calculate a capillary resistance index indicating the amount of capillary resistance in the capillaries supplying blood to the myocardial region. For example, the calculation function 354 calculates the capillary resistance index based on the ratio between the vascular blood flow rate and the myocardial blood flow rate. Fig. 2 is a diagram for explaining an example of the calculation of the capillary resistance index by the medical information processing device 300 according to the first embodiment.

[0040] 2 shows a case where the vascular blood flow rate at a position P1 of the coronary artery and the myocardial blood flow rate at a region R1 of the myocardium are acquired. As described above, the position P1 and the region R1 may be determined by the operator specifying the coronary artery, or may be determined by the operator specifying the myocardial region.

[0041] The calculation function 354 calculates the capillary resistance index corresponding to the coronary artery position P1 and the myocardial region R1 using the vascular blood flow rate at the coronary artery position P1 and the myocardial blood flow rate in the myocardial region R1. For example, the calculation function 354 calculates the capillary resistance index by the following formula.

[0042] Capillary resistance index = myocardial blood flow (Q myo ) / vascular blood flow (Q vessel )

[0043] That is, the calculation function 354 can calculate the blood supply ability from the coronary artery to the myocardial region (the degree of inhibition of blood flow in the capillaries between the coronary artery and the myocardium) by calculating the ratio between the vascular blood flow of the coronary artery and the myocardial blood flow of the myocardial region controlled by the coronary artery. Here, for example, when the capillary resistance is high, the blood supply from the coronary artery to the myocardial region decreases, so the capillary resistance index becomes smaller than "1". On the other hand, when the capillary resistance is low, the blood supply from the coronary artery to the myocardial region does not decrease, so the capillary resistance index approaches "1".

[0044] For example, the calculation function 354 calculates the “vascular blood flow rate (Q vessel ) and myocardial blood flow (Q myo )" and based on the above formula, the capillary resistance index corresponding to the position P1 and the myocardial region R1 is calculated.

[0045] In the above-described embodiment, the capillary resistance index is calculated for a single coronary artery and region. However, the embodiment is not limited thereto, and the medical information processing device 300 can also calculate the capillary resistance index for a myocardial region governed by multiple coronary arteries. In such a case, for example, the acquisition function 352 acquires multiple vascular blood flow rates in multiple coronary arteries and a single myocardial blood flow rate that is a combination of multiple myocardial blood flow rates in multiple myocardial regions to which blood is respectively supplied by the multiple coronary arteries. Then, the calculation function 354 calculates the capillary resistance index by combining the multiple vascular blood flow rates and the single myocardial blood flow rate.

[0046] FIG. 3 is a diagram for explaining an example of calculation of the capillary resistance index by the medical image processing device 300 according to the first embodiment. Here, FIG. 3 shows a case where the capillary resistance index of a myocardial region governed by two coronary arteries is calculated. For example, in the example of FIG. 3, a target region for calculating the capillary resistance index is specified, and the acquisition function 352 identifies the ranges of the two coronary arteries that supply blood to the specified target region. Then, the acquisition function 352 calculates the vascular blood flow rate "Q vessel1 " and the vascular blood flow rate at position P3 "Q vessel2 " to get

[0047] Furthermore, the acquisition function 352 identifies the control area of ​​each of the two identified coronary arteries by the Voronoi method, and extracts a single area R2 by combining the identified control areas. Then, the acquisition function 352 calculates the myocardial blood flow rate "Q myo Note that the determination of the position P2, the position P3, and the region R2 described above is merely an example, and for example, the position P2 and the position P3 may be designated by the operator, and the acquisition function 352 may specify the region R2 based on the designated position P2 and position P3.

[0048] As described above, the acquisition function 352 acquires the blood vessel blood flow rate “Q vessel1" and the vascular blood flow rate at position P3 "Q vessel2 ” and myocardial blood flow in region R2 “Q myo ", the calculation function 354 calculates, for example, "myocardial blood flow (Q myo ) / (vascular blood flow (Q vessel1 ) + vascular blood flow (Q vessel2 )) to calculate the capillary resistance index in region R2.

[0049] In the above example, when the range of blood supply to the myocardial region is specified, only the end on the branching side is specified. However, the embodiment is not limited to this, and for example, the end on the branching side and the end on the peripheral side may be specified. In such a case, the acquisition function 352 acquires the vascular blood flow rate at the upstream end and the downstream end of the range of the coronary artery supplying blood to the myocardial region, and the myocardial blood flow rate in the specified myocardial region. Then, the calculation function 354 calculates an index by combining the difference between the vascular blood flow rate at the upstream end and the vascular blood flow rate at the downstream end and the myocardial blood flow rate in the specified myocardial region.

[0050] FIG. 4 is a diagram for explaining an example of calculation of the capillary resistance index by the medical information processing device 300 according to the first embodiment. Here, FIG. 4 shows a case where the capillary resistance index of a myocardial region governed by a predetermined range in one coronary artery is calculated. For example, in the example of FIG. 4, the target region for calculating the capillary resistance index is specified within the predetermined range in one coronary artery, and the acquisition function 352 identifies the range of the coronary artery (the end on the bifurcation side and the end on the peripheral side of the coronary artery) that supplies blood to the specified target region. Then, the acquisition function 352 calculates the vascular blood flow rate "Q vessel3 " and the vascular blood flow rate at position P5 "Q vessel4 Furthermore, the acquisition function 352 acquires "Q vessel3 -Q vessel4 " is calculated.

[0051] Then, the acquisition function 352 identifies a myocardial region R3 governed by the range of the identified coronary artery by the Voronoi method. Then, the acquisition function 352 obtains the myocardial blood flow rate "Q myo Note that the determination of the positions P4, P5, and the region R3 described above is merely an example, and for example, the positions P4 and P5 may be designated by the operator, and the acquisition function 352 may identify the region R3 based on the designated positions P4 and P5.

[0052] As described above, the acquisition function 352 acquires the vascular blood flow rate “Q vessel3 -Q vessel4 ” and myocardial blood flow in region R3 “Q myo ", the calculation function 354 calculates, for example, "the myocardial blood flow in the region R3 (Q myo ) / (vascular blood flow (Q vessel3 )-vascular blood flow (Q vessel4 )) to calculate the capillary resistance index corresponding to the coronary artery from position P4 to position P5 and region R3.

[0053] In the above example, the capillary resistance index is calculated for a single myocardial region. However, the embodiment is not limited to this. For example, the myocardial region may be divided into partial regions, and the capillary resistance index may be calculated for each partial region. In this case, the acquisition function 352 divides the coronary artery and the myocardial region to which blood is supplied by the coronary artery into a plurality of ranges, and acquires the vascular blood flow rate at the upstream end of the range and the vascular blood flow rate at the downstream end of the range, and the myocardial blood flow rate in the myocardial region corresponding to the range, for each divided range. Then, the calculation function 354 combines the difference between the vascular blood flow rate at the upstream end and the vascular blood flow rate at the downstream end with the myocardial blood flow rate in the myocardial region corresponding to the range, and calculates the capillary resistance index for each divided range.

[0054] 5A is a diagram for explaining an example of calculation of a capillary resistance index by the medical information processing device 300 according to the first embodiment. Here, FIG. 5A shows a case where a myocardial region governed by a coronary artery is divided into a plurality of partial regions, and a capillary resistance index is calculated for each partial region. For example, in the example of FIG. 5A, a target region for calculating a capillary resistance index is specified, and the acquisition function 352 identifies the range of the coronary artery that supplies blood to the specified target region (position P6 of the end of the coronary artery on the bifurcation side). Then, the acquisition function 352 identifies a myocardial region R4 governed by the specified range of the coronary artery by the Voronoi method.

[0055] Then, the acquisition function 352 acquires the core line of the coronary artery in the specified range, and divides the coronary artery and myocardial region R4 into a plurality of ranges in a direction perpendicular to the core line. As an example, the acquisition function 352 divides the region R4 into partial regions R411 and R412 by a line segment perpendicular to the core line of the coronary artery and passing through the position P61. That is, the acquisition function 352 divides the range including the region of the coronary artery from the position P6 to the position P61, and the partial regions R411 and R412 from the coronary artery and region R4 by a line segment passing through the position P61.

[0056] The acquisition function 352 also divides the region R4 into partial regions R421 and R422 by a line segment that is perpendicular to the core line of the coronary artery and passes through position P62, and divides the region from position P61 to position P62 from the coronary artery. Similarly, the acquisition function 352 divides the partial regions R431-R492 and the partial region R42 by each line segment that passes through positions P63-P610.

[0057] Then, the acquisition function 352 acquires the vascular blood flow rate and the myocardial blood flow rate for each of the divided ranges. As an example, the acquisition function 352 acquires the vascular blood flow rate and the myocardial blood flow rate for the range including the region of the coronary artery from position P6 to position P61, partial region R411 and partial region R412. For example, the acquisition function 352 acquires the vascular blood flow rate "Q vessel6 " and the vascular blood flow rate at position P61 "Q vessel61Furthermore, the acquisition function 352 acquires "Q vessel6 -Q vessel61 In addition, the acquisition function 352 calculates the myocardial blood flow rate "Q myo411 " and myocardial blood flow in the partial region R421 "Q myo421 " to get

[0058] Similarly, the acquisition function 352 acquires vascular blood flow and myocardial blood flow for each range from the region of the coronary artery from position P61 to position P62, and the range including partial regions R421 and R422, to the region of the coronary artery from position P610 to the end of the coronary artery, and the range including partial region R42.

[0059] The calculation function 354 calculates the capillary resistance index for each partial region by using the vascular blood flow rate for each range and the myocardial blood flow rate in the partial region acquired by the acquisition function 352. For example, the calculation function 354 calculates "Q myo411 / (Q vessel6 -Q vessel61 In addition, the calculation function 354 calculates "Q myo421 / (Q vessel6 -Q vessel61 The calculation function 354 may calculate, for example, an average of the capillary resistance index in the partial region R411 and the capillary resistance index in the partial region R421 as the capillary resistance index corresponding to the coronary artery from the position P6 to the position P61.

[0060] Similarly, the calculation function 354 calculates a capillary resistance index for each partial region for each range from the region of the coronary artery from position P61 to position P62 and the range including partial regions R421 and R422 to the region of the coronary artery from position P610 to the coronary artery end and the range including partial region R42. For the range including the region of the coronary artery from position P610 to the coronary artery end and partial region R42, one capillary resistance index is calculated from the myocardial blood flow in the region of the coronary artery from position P610 to the coronary artery end and the myocardial blood flow in the partial region R42.

[0061] Here, the division example shown in Fig. 5A is merely an example, and the embodiment is not limited thereto. That is, the number of partial regions when dividing the region R4 is not limited to the number shown in Fig. 5A, and may be divided into more partial regions than the number shown in Fig. 5A, or may be divided into less than the number shown in Fig. 5A.

[0062] In the above example, the case of dividing the control area of ​​one coronary artery is described. In the following, the case of dividing the control area of ​​a region where the coronary artery branches is described. FIG. 5B is a diagram for explaining an example of calculation of a capillary resistance index by the medical information processing device 300 according to the first embodiment. Here, FIG. 5B shows an enlarged view of the region where the coronary artery branches. That is, in the case shown in FIG. 5B, the range of the coronary artery and the myocardial region controlled by the coronary artery in that range are actually specified, similarly to FIG. 5A.

[0063] For example, in the example of FIG. 5B, the acquisition function 352 first divides the region of the coronary artery from position P71 to position P72 into a range including the partial regions R511 and R512, and the region of the coronary artery from position P72 to position P73 into a range including the partial regions R521 and R522. The acquisition function 352 then further divides the partial region R522, which includes a branch, into a plurality of ranges. For example, the acquisition function 352 divides the region of the coronary artery from position P721 to position P722 into a range including the partial regions R5221 and R5222 from the partial region R522. Similarly, the acquisition function 352 divides a plurality of ranges from the partial region R522, which includes a branch.

[0064] After dividing the area as described above, the acquisition function 352 acquires the vascular blood flow rate and the myocardial blood flow rate for each area. That is, the acquisition function 352 acquires the vascular blood flow rate of the coronary artery and the myocardial blood flow rate for each partial area for each divided area. For example, the acquisition function 352 acquires the vascular blood flow rate and the myocardial blood flow rate for the area of ​​the coronary artery from position P71 to position P72 and the area including partial areas R511 and R512 in the same manner as described in FIG. 5A.

[0065] The acquisition function 352 acquires the blood flow rate of each region for the range including the region of the coronary artery from position P72 to position P73, the partial region R521, and the partial region R522 including the branch, for example, as follows. First, as the blood flow rate for calculating the capillary resistance index in the partial region R521 not including the branch, the acquisition function 352 acquires the blood flow rate of the blood vessel at position P72, "Q vessel72 " and the vascular blood flow rate at position P73 "Q vessel73 Furthermore, the acquisition function 352 acquires "Q vessel72 -Q vessel73 The acquisition function 352 also calculates the myocardial blood flow rate "Q myo521 " to get

[0066] On the other hand, as the blood flow rate for calculating the capillary resistance index in the partial region R522 including the branch, the acquisition function 352 acquires the blood flow rate of the blood vessel at the position P72, “Q vessel72 ” and the vascular blood flow rate at branch position P721 “Q vessel721 " and the vascular blood flow rate at position P73 "Q vessel73 " and the vascular blood flow rate at position P722 "Q vessel722 " and the vascular blood flow rate at position P723 "Q vessel723 " and the vascular blood flow rate at position P724 "Q vessel724 Then, the acquisition function 352 acquires the blood flow rate "Q vessel72 -Q vessel721 ', and the vascular blood flow rate in the coronary artery from position P721 to position P73, "Q vessel721 -Q vessel73 ” and the vascular blood flow rate in the coronary artery from position P721 to position P722 “Q vessel721 -Q vessel722 ” and the vascular blood flow rate in the coronary artery from position P722 to position P723 “Q vessel722 -Q vessel723 ” and the vascular blood flow rate in the coronary artery from position P723 to position P724 “Q vessel723 -Q vessel724 " is calculated.

[0067] Furthermore, the acquisition function 352 acquires the myocardial blood flow “Q myo5221 " and myocardial blood flow in the partial region R5221 "Q myo5221 The myocardial blood flow in each of the partial regions divided from the partial region R522 including " is obtained.

[0068] As described above, when the blood flow rate in each region is acquired, the calculation function 354 calculates the capillary resistance index for each divided range using each blood flow rate. For example, the calculation function 354 calculates the capillary resistance index for the range including the coronary artery region from position P71 to position P72 and the partial region R511 and the partial region R512 in the same manner as described in FIG. 5A.

[0069] On the other hand, for a range including a partial region R522 including a branch, the calculation function 354 calculates the capillary resistance index, for example, as follows. First, for the capillary resistance index in a partial region R521 not including a branch, the calculation function 354 calculates the capillary resistance index in the range including a branch, for example, as follows. myo521 / (Q vessel72 -Q vessel73 )" is calculated.

[0070] For the capillary resistance index in each partial region included in the partial region R522 including the branch, the calculation function 354 calculates, for example, "Q myo5221 / ((Q vessel72 -Q vessel721 )+(Q vessel721 -Q vessel722 That is, the calculation function 354 calculates the capillary resistance index taking into consideration the supply of blood from the coronary artery from position P72 to position P721 and the supply of blood from the coronary artery from position P721 to position P722.

[0071] Similarly, the calculation function 354 calculates, as the capillary resistance index in the partial region R5222, a capillary resistance index “Q myo5222 / ((Q vessel721 -Q vessel73 )+(Q vessel721 -Q vessel722 For the range thereafter, the calculation is performed in the same manner as above. That is, for example, for the range from position P722 to position P723, the calculation function 354 calculates the vascular blood flow rate "Q vessel722 -Q vessel723 " is calculated to calculate the capillary resistance index for each partial region of both armpits.

[0072] Note that the division example shown in Fig. 5B is merely an example, and the embodiment is not limited thereto. That is, the number of partial regions at the time of division is not limited to the number shown in Fig. 5B, and may be divided into more partial regions than the number shown in Fig. 5B, or may be divided into less than the number shown in Fig. 5B.

[0073] As described above, the acquisition function 352 and the calculation function 354 according to this embodiment calculate the capillary resistance index from the vascular blood flow rate in the coronary artery and the myocardial blood flow rate in the myocardium. Here, the above-mentioned calculation of the capillary resistance index can be applied to the entire heart. That is, the acquisition function 352 and the calculation function 354 can calculate the capillary resistance index for the myocardium of the entire heart and the right coronary artery (RCA), the left anterior descending coronary artery (LAD), and the left circumflex coronary artery (LCX) including all branched blood vessels.

[0074] The setting of the target region for calculating the capillary resistance index, whether or not to divide the target region, and the number of divisions when dividing the target region can be arbitrarily set by the operator. For example, they can be arbitrarily set each time the capillary resistance index is calculated. Also, conditions may be set in advance for each target region for calculating the capillary resistance index. In such a case, for example, when the myocardial region at the apex of the heart is set as the target region, the capillary resistance index may be set in advance to calculate the capillary resistance index using the vascular blood flow rate in three blood vessels, the RCA, the LAD, and the LCX.

[0075] In addition, the above-mentioned vascular blood flow and myocardial blood flow may be acquired in either a stressed state or a resting state. That is, the acquisition function 352 and the calculation function 354 according to this embodiment can calculate the capillary resistance index in a stressed state and the capillary resistance index in a resting state.

[0076] Returning to FIG. 1, the determination function 355 determines the state of the target region based on the capillary resistance index calculated by the calculation function 354. For example, the determination function 355 determines whether or not microcirculation is sufficiently maintained in the supply of blood to the myocardium by comparing the calculated capillary resistance index value with a threshold value. As an example, when the capillary resistance index value is lower than a predetermined threshold value, the determination function 355 determines that the supply of blood in the capillaries is inhibited.

[0077] Also, for example, the determination function 355 can compare the capillary resistance index calculated in the stress state and the resting state to determine the state of the target region. For example, the determination function 355 compares the capillary resistance index calculated in the stress state and the resting state in the region where ischemia occurs, and if there is no difference between the two, determines that a coronary artery disorder has occurred.

[0078] Also, for example, the determination function 355 can determine a treatment plan using the capillary resistance index and other test information. The determination of a treatment plan will be described in detail later.

[0079] As described above, the medical information processing device 300 according to this embodiment can calculate the capillary resistance index for the entire heart. Furthermore, the medical information processing device 300 can display the calculated capillary resistance index in various forms. That is, the control function 351 can display information on the capillary resistance index calculated by the calculation function 354 on the display 340. Hereinafter, examples of the display form of the capillary resistance index according to this embodiment will be described with reference to Figs. 6 to 16. Figs. 6 to 16 are diagrams showing examples of the display form of the capillary resistance index according to the first embodiment.

[0080] For example, the control function 351 controls to display a display image showing information related to the capillary resistance index calculated by the calculation function 354 on a medical image including at least one of a myocardial region and a coronary artery. As an example, the control function 351 displays a color image showing an area R1 on a volume rendering image showing the entire heart in a color according to the value of the calculated capillary resistance index, as shown in Fig. 6.

[0081] In such a case, the image generating function 353 generates a volume rendering image of the entire heart from, for example, the acquired CT image data. The control function 351 displays a color image in which the region R1 of the generated volume rendering image is displayed in a color according to the calculated value of the capillary resistance index. Note that the color can be arbitrarily assigned to the capillary resistance index. Note that the example shown in FIG. 6 is merely an example, and various other images can be used as the display image. For example, a surface rendering image may be used.

[0082] The control function 351 also controls to display the capillary resistance index calculated for each divided range in color and to display the assigned color image on the three-dimensional image showing the myocardial region or the coronary artery. For example, when the target region is divided into partial regions and the capillary resistance index for each partial region is calculated, the control function 351 displays a color image showing each partial region in a color according to the value of the capillary resistance index calculated for each divided partial region for the region R1 on the volume rendering image showing the myocardium, as shown in Fig. 7A.

[0083] Also, for example, when the target region is divided into partial regions and the capillary resistance index for each partial region is calculated, the control function 351 displays a color image showing each region corresponding to each range of the coronary artery on the volume rendering image showing the coronary artery in a color corresponding to the value of the capillary resistance index, as shown in Fig. 7B. In such a case, the image generating function 353 generates a volume rendering image of the coronary artery from the acquired CT image data, for example. The control function 351 displays a color image showing each region of the coronary artery in the generated volume rendering image in a color corresponding to the value of the capillary resistance index.

[0084] Here, when a range including multiple partial regions is targeted (for example, when a range including partial regions R411 and R412 in Figure 5A is targeted), the value of the capillary resistance index assigned to the coronary artery region in that range (for example, the region from position P1 to position P61 in Figure 5A) may be the average of the capillary resistance indexes in each partial region, or may be the lowest capillary resistance index among the capillary resistance indexes for each partial region.

[0085] In addition, when a plurality of capillary resistance indices along a coronary artery are calculated in detail by fine division, the control function 351 can display a graph showing the capillary resistance index for each position of the coronary artery. For example, the control function 351 controls to display a display image showing the coronary artery on a two-dimensional plane along the long axis direction and a graph showing the change in the index calculated for each range of the coronary artery, with the positions in the display image corresponding to the positions in the graph.

[0086] As an example, the control function 351 displays a graph showing the capillary resistance index on the vertical axis and the position of the coronary artery on the horizontal axis as shown in FIG. 8A. Furthermore, the control function 351 displays an SPR image with the position of the coronary artery on the horizontal axis in correspondence with the graph. In such a case, the image generating function 353 generates, for example, an SPR image of the coronary artery for which the capillary resistance index has been calculated from the CT image data. Furthermore, the image generating function 353 generates a graph of the capillary resistance index at a scale where the position of the generated SPR image in the coronary artery corresponds to the position on the horizontal axis of the graph. The control function 351 displays the graph and the SPR image generated by the image generating function 353 in correspondence with each other as shown in FIG. 8A.

[0087] Furthermore, the control function 351 can also perform control so as to display the result of myocardial perfusion on the display image. For example, the control function 351 displays a color image in which the myocardial region of the SPR image is shown in a color corresponding to the result of the myocardial blood flow calculated by the acquisition function 352, as shown in FIG. 8B.

[0088] Furthermore, the medical information processing device 300 can use a polar map to display the entire myocardium. For example, the control function 351 controls to display the coronary arteries and myocardial regions in a distinguishable manner on a display image in which the myocardium is displayed in polar coordinates, and to display a color image in which the calculated index for each divided range is indicated by color. As an example, the control function 351 displays a display image in which the coronary arteries and the target region in which the capillary resistance index is calculated are superimposed on the polar map in which the entire myocardium is displayed in polar coordinates, as shown in FIG. 9.

[0089] In such a case, the image generating function 353 generates an image of the coronary artery and an image of the target region, each having a shape that matches the position on the polar map. Then, the control function 351 displays the generated image of the coronary artery and the image of the target region, superimposed on the corresponding position on the polar map. Here, the control function 351 displays a color image by showing each partial region of the target region in a color according to the value of the capillary resistance index calculated by the calculation function 354, as shown in FIG. 9.

[0090] As described above, the control function 351 can display the capillary resistance index in various display forms. Here, the control function 351 can display a suitable combination of the display images in the various forms described above. For example, the control function 351 can display all the display images shown in Figs. 6 to 9 side by side, or display a plurality of display images selected from the display images side by side.

[0091] Here, when multiple display images are displayed side by side, the control function 351 can display a marker indicating the positional relationship between the images. For example, when color images, graphs, SPR images, polar maps, etc. are displayed side by side, the control function 351 arranges and displays markers indicating approximately the same position for those images.

[0092] As an example, as shown in FIG. 10, when displaying a graph showing the capillary resistance index on the vertical axis and the position of the coronary artery on the horizontal axis, an SPR image with the position of the coronary artery on the horizontal axis aligned, and a color image using a volume rendering image of the coronary artery, the control function 351 displays markers M1 and M2 indicating approximately the same position on the coronary artery.

[0093] That is, the control function 351 acquires information on the positional relationship between the position on the horizontal axis of the graph (SPR image) and the position of the coronary artery in the volume rendering image, based on the coordinate information at the time of generating the SPR image and the volume rendering image by the image generating function 353. Then, based on the acquired information on the positional relationship, the control function 351 places a marker M1 indicating approximately the same position on the coronary artery on the horizontal axis of the graph (or SPR image), and places a marker M2 on the coronary artery in the volume rendering image.

[0094] Here, the display of the marker may be started at the same time that the multiple display images are displayed, or may be started in response to an instruction to start displaying the marker by the operator via the input interface 330. The marker is moved in response to a movement instruction by the operator via the input interface 330. That is, the control function 351 moves the marker to a position corresponding to the marker movement operation via the input interface 330 and displays it. At this time, the control function 351 moves the multiple markers arranged on each display image in a linked manner. For example, when the operator executes an operation to move the marker M1, the control function 351 also moves the marker M2 in a linked manner.

[0095] Furthermore, the control function 351 can also display a short-axis cross-sectional image at a specified position in the coronary artery. For example, when a marker is placed on the coronary artery, the control function 351 controls so as to further display a short-axis cross-sectional image of the coronary artery at the position where the marker is placed. For example, as shown in Fig. 10, when a marker M1 is placed on the coronary artery, the image generating function 353 first generates a cross-cut image (a cross-sectional image perpendicular to the core line) at the position where the marker M1 is placed. The control function 351 displays the generated short-axis cross-sectional image at a position corresponding to the marker M1 on the horizontal axis of the SPR image (or graph).

[0096] In the above example, the capillary resistance index is displayed in various display forms. However, the medical information processing device 300 can further display index values ​​other than the capillary resistance index.

[0097] For example, the control function 351 controls to superimpose a 3D image showing the coronary artery and a color image showing the index for each range in color on the 3D image showing the myocardial region, and further displays a marker indicating a position in the coronary artery and the fractional flow reserve at the position of the marker. As an example, the control function 351 displays a marker M3 on a superimposed image in which a volume rendering image showing the coronary artery and a volume rendering image of the region R6 in which the capillary resistance index has been calculated are superimposed, as shown in Fig. 11. Then, the control function 351 further displays the FFR value "0.8" at the marker M3.

[0098] That is, the control function 351 acquires the FFR value at the position of the marker M3 from the result of the fluid analysis by the acquisition function 352, and displays it at the position of the marker M3 in the superimposed image. Here, the position of the marker M3 is moved by a movement operation by the operator via the input interface 330. Each time the marker M3 is moved by the movement operation, the control function 351 acquires the FFR value at the position of the marker M3 after the movement, and displays it at the position of the marker M3 in the superimposed image.

[0099] Also, for example, the control function 351 controls to display a three-dimensional image showing the coronary artery, a marker indicating a position in the coronary artery, and the capillary resistance index and the fractional flow reserve at the position of the marker. As an example, the control function 351 displays markers M3 and M4 on a volume rendering image showing the coronary artery as shown in Fig. 12. Then, the control function 351 further displays the FFR value "0.8" at marker M3 and the capillary resistance index value "0.9" at marker M4.

[0100] Here, the positions of marker M3 and marker M4 are moved by a movement operation by the operator via the input interface 330. The control function 351 acquires the value of the FFR at the position of marker M3 after the movement every time marker M3 is moved by the movement operation, and displays it at the position of marker M3 in the volume rendering image. Also, the control function 351 displays the value of the capillary resistance index at the position of marker M4 after the movement at the position of marker M4 in the volume rendering image every time marker M4 is moved by the movement operation. Note that marker M3 and marker M4 can be controlled so that the other moves in conjunction with the movement operation of either one of them. That is, marker M3 and marker M4 can be moved separately from each other, and can also be moved in conjunction with each other.

[0101] Also, for example, the control function 351 controls to display the result of myocardial perfusion on a display image in which the myocardium is displayed in polar coordinates, and to identifiably display a region in the myocardial region included in the display image in which the capillary resistance index is lower than a threshold. As an example, the control function 351 assigns a color according to the value of the myocardial blood flow obtained by myocardial perfusion to the polar map as shown in Fig. 13, and further causes the region in which the capillary resistance index is lower than the threshold to be identifiably displayed. Here, the control function 351 causes the region lower than the threshold to be identifiably displayed, for example, by surrounding it with a frame or masking it with a different color.

[0102] Also, for example, the control function 351 controls to display the result of myocardial perfusion on a three-dimensional image showing the myocardium, and to identifiably display a region in the myocardial region included in the three-dimensional image where the index is lower than the threshold. As an example, the control function 351 assigns a color according to the value of myocardial blood flow obtained by myocardial perfusion to the polar map as shown in Fig. 14, and further displays a region where the capillary resistance index is lower than the threshold in an identifiable manner. Here, the control function 351 identifiably displays the region where the capillary resistance index is lower than the threshold, for example, by surrounding the region lower than the threshold with a frame or masking it with a different color.

[0103] Also, for example, the control function 351 controls to display a three-dimensional image showing a coronary artery, and when a designation operation for designating a position on the coronary artery in the three-dimensional image is received, to display side by side the fractional flow reserve at the received position, the result of myocardial perfusion in the myocardial region to which blood is supplied by the coronary artery at the received position, the capillary resistance index at the received position, and a value based on the pixel value at the received position. That is, the control function 351 can display various indexes simultaneously when a position on the coronary artery is designated.

[0104] As an example, the control function 351 positions and displays a marker M5 for designating a position in the coronary artery for the coronary artery in a volume rendering image of the coronary artery as shown in Fig. 15. Then, the control function 351 displays "FFR: aaa", "MBF: bbb", "capillary resistance index: ccc", and "TAG: ddd" side by side at the position of the marker M5.

[0105] MBF (Myocardial Blood Flow) is the myocardial blood flow rate, and the myocardial blood flow rate in the myocardium adjacent to the position of the marker M5 is displayed. TAG (Transluminal Attenuation Gradient) is a value based on pixel values ​​(HU values) in the coronary artery, and is the slope (spatial rate of change in HU value) of a graph in which the horizontal axis represents the distance from the upstream side to the downstream side along the core line of the coronary artery, and the vertical axis represents the HU value at each distance.

[0106] For example, the slower the blood flow is, the longer it takes for the contrast agent to travel the distance between two points on the coronary artery after it is injected, so the difference in contrast effect is greater in blood vessels where blood flow is reduced due to a lesion, and the slower the blood flow is, the larger the TAG becomes. Note that the TAG is calculated by the acquisition function 352 using the coronary angiography CT image data.

[0107] In addition, for example, the control function 351 displays a three-dimensional image showing the myocardium, and when a designation operation for designating a myocardial region in the three-dimensional image is received, controls to display side by side the fractional coronary flow reserve in the coronary artery supplying blood to the received myocardial region, the result of myocardial perfusion in the received myocardial region, and the capillary resistance index in the received myocardial region.

[0108] As an example, when a region R1 for calculating the capillary resistance index for the myocardium in a volume rendering image of the heart is specified, as shown in Figure 16, the control function 351 displays "FFR: eee" at position P1 of the coronary artery that supplies blood to region R1, "MBF: fff" in region R1, and "capillary resistance index: ggg" in region R1 side by side.

[0109] Also, for example, the control function 351 displays a recommended treatment plan for at least one of the accepted position and the accepted myocardial region based on a comparison result between each display item displayed side by side and a threshold value set for each display item. For example, the control function 351 can display a recommended treatment plan when multiple display items (FFR, MBF, etc.) are displayed side by side as shown in Fig. 15 and Fig. 16.

[0110] In such a case, first, the determination function 355 determines a recommended treatment plan by comparing each display item with a threshold value. For example, the determination function 355 determines a recommended treatment plan based on the determination criteria shown in FIG. 17. FIG. 17 is a diagram for explaining an example of the determination criteria for determining a treatment plan according to the first embodiment. Here, FIG. 17 shows the determination criteria used to determine a treatment plan using FFR, MBF, and a capillary resistance index. Also, an upward arrow (↑) in FIG. 17 indicates a value higher than the threshold value, and a downward arrow (↓) indicates a value lower than the threshold value.

[0111] 17 are preset and stored in the storage circuitry 320. That is, the determination function 355 performs a determination by referring to the determination criteria stored in the storage circuitry 320. Also, each threshold value used for determining each display item is preset by an operator or the like.

[0112] For example, as shown in FIG. 17, when "FFR:↓, MBF:↓, capillary resistance index:↑", the determination function 355 determines "catheter treatment" as the "recommended treatment". Also, as shown in FIG. 17, when "FFR:↑, MBF:↓, capillary resistance index:↓", the determination function 355 determines "drug treatment" as the "recommended treatment". Also, as shown in FIG. 17, when "FFR:↓, MBF:↑, capillary resistance index:↑", the determination function 355 determines "no treatment required" as the "recommended treatment". Also, as shown in FIG. 17, when "FFR:↓, MBF:↓, capillary resistance index:↓", the determination function 355 determines "catheter treatment" and "drug treatment" as the "recommended treatment".

[0113] The control function 351 displays the results (recommended treatments) determined by the determination function 355 in association with each display item in the display image. The above-mentioned determination of the recommended treatment can be performed for each position of the coronary artery or for each myocardial region. That is, each time the operator uses the input interface 330 to move the marker M5 or to specify a target region for calculating the capillary resistance index, the determination function 355 determines a recommended treatment policy for each position after the movement, and the control function 351 displays the determination result.

[0114] 17 is merely an example, and the embodiment is not limited to this. For example, TAG or other indexes may be used as items to be compared with the threshold value.

[0115] Next, a procedure of processing by the medical image processing apparatus 300 according to the first embodiment will be described. FIG. 18 is a flowchart showing the procedure of processing by the medical image processing apparatus 300 according to the first embodiment. Here, step S101 and step S111 in FIG. 18 are realized, for example, by the processing circuitry 350 calling a program corresponding to the control function 351 from the storage circuitry 320 and executing the program. Also, step S103 to step S108 are realized, for example, by the processing circuitry 350 calling a program corresponding to the acquisition function 352 from the storage circuitry 320 and executing the program. Also, step S109 is realized, for example, by the processing circuitry 350 calling a program corresponding to the calculation function 354 from the storage circuitry 320 and executing the program. Also, step S102 and step S110 are realized, for example, by the processing circuitry 350 calling a program corresponding to the control function 351 and the image generation function 353 from the storage circuitry 320 and executing the program.

[0116] In the medical image processing device 300 according to this embodiment, the processing circuitry 350 first acquires CT image data (step S101). Then, the processing circuitry 350 generates and displays an image of the heart from the CT image data (step S102). Then, the processing circuitry 350 determines whether or not a position designation for a coronary artery has been received (step S103). Here, when a position designation for a coronary artery has been received (Yes in step S103), the processing circuitry 350 identifies a myocardial region to which blood is supplied by the designated coronary artery (step S104), and calculates the vascular blood flow rate in the designated coronary artery and the myocardial blood flow rate in the identified myocardial region (step S105).

[0117] On the other hand, if no designation of a position of a coronary artery has been received in step S103 (step S103: No), the processing circuitry 350 judges whether or not designation of a region of the myocardium has been received (step S106). If designation of a region of the myocardium has been received (step S106: Yes), the processing circuitry 350 identifies a coronary artery that supplies blood to the designated myocardial region (step S107), and calculates the myocardial blood flow rate in the designated myocardial region and the vascular blood flow rate in the identified coronary artery (step S108). If no designation of a region of the myocardium has been received in step S106 (step S106: No), the processing circuitry 350 returns to step S103 and continues the judgment.

[0118] After calculating the vascular blood flow rate and myocardial blood flow rate in step S105 or step S108, the processing circuit 350 calculates a capillary resistance index using the vascular blood flow rate and myocardial blood flow rate (step S109). Then, the processing circuit 350 generates and displays information related to the calculated capillary resistance index (step S110). After that, the processing circuit 350 judges whether the calculation of the capillary resistance index has been completed (step S111), and if it has been completed (step S111, yes), the processing ends. On the other hand, if it has not been completed (step S111, no), the processing circuit 350 returns to step S103 and continues the judgment.

[0119] As described above, according to the first embodiment, the acquisition function 352 acquires the vascular blood flow rate in the coronary artery and the myocardial blood flow rate in the myocardial region to which blood is supplied by the coronary artery. The calculation function 354 combines the vascular blood flow rate and the myocardial blood flow rate to calculate an index indicating the capillary resistance in the capillaries supplying blood to the myocardial region. Therefore, the medical information processing device 300 according to the first embodiment can calculate the blood supply ability from the coronary artery to the myocardial region (the degree of inhibition of blood flow in the capillaries between the coronary artery and the myocardium), and can provide an index for evaluating the resistance in the capillaries.

[0120] For example, CFR (Coronary Flow Reserve) is known as an index for diagnosing myocardial ischemia. The capillary resistance index according to the present application has a similar clinical meaning to this CFR. However, since CFR is the ratio of myocardial blood flow in a stressed state to that in a resting state, in order to calculate it from CT image data, imaging must be performed twice, in a stressed state and in a resting state, resulting in a large amount of radiation exposure. In addition, in order to calculate CFR, a vasodilator is used to put blood vessels in a stressed state, which places a burden on the subject.

[0121] In contrast, the capillary resistance index according to the present application can be calculated by acquiring CT image data of multiple time phases corresponding to multiple heartbeats, and the amount of radiation exposure can be reduced. In addition, the capillary resistance index according to the present application can be calculated in a resting state, so that the burden of administering drugs to the subject is not imposed. In other words, the capillary resistance index according to the present application can be calculated even in subjects to whom vasodilators cannot be administered.

[0122] Furthermore, the capillary resistance index according to the present application uses the coronary artery blood flow rate and myocardial blood flow rate, which can be calculated by various techniques, and therefore can be calculated in various subjects.

[0123] According to the first embodiment, the acquisition function 352 acquires a plurality of vascular blood flow rates in a plurality of coronary arteries and a single myocardial blood flow rate obtained by combining a plurality of myocardial blood flow rates in a plurality of myocardial regions to which blood is respectively supplied by the plurality of coronary arteries. The calculation function 354 calculates a capillary resistance index by combining the plurality of vascular blood flow rates and the single myocardial blood flow rate. Thus, the medical information processing device 300 according to the first embodiment makes it possible to provide a capillary resistance index that more accurately reflects the supply of blood from the coronary arteries to the myocardium.

[0124] Furthermore, according to the first embodiment, the acquisition function 352 acquires the vascular blood flow rate at the upstream end and downstream end of the range of the coronary artery supplying blood to the myocardial region, and the myocardial blood flow rate in the specified myocardial region. The calculation function 354 calculates a capillary resistance index by combining the difference between the vascular blood flow rate at the upstream end and the vascular blood flow rate at the downstream end, and the myocardial blood flow rate in the specified myocardial region. Therefore, the medical information processing device 300 according to the first embodiment makes it possible to provide a more accurate capillary resistance index.

[0125] According to the first embodiment, the acquisition function 352 divides the coronary arteries and the myocardial region to which blood is supplied by the coronary arteries into a plurality of ranges, and acquires, for each divided range, the vascular blood flow rate at the upstream end and the vascular blood flow rate at the downstream end of the range, and the myocardial blood flow rate in the myocardial region corresponding to the range. The calculation function 354 combines the difference between the vascular blood flow rate at the upstream end and the vascular blood flow rate at the downstream end with the myocardial blood flow rate in the myocardial region corresponding to the range, and calculates a capillary resistance index for each divided range. Thus, the medical information processing device 300 according to the first embodiment makes it possible to provide a capillary resistance index for a finer region.

[0126] Furthermore, according to the first embodiment, the control function 351 controls to display a display image showing information on the capillary resistance index calculated by the calculation function 354 on a medical image including at least one of a myocardial region and a coronary artery. Therefore, the medical information processing device 300 according to the first embodiment makes it possible to provide more easily understandable information on the capillary resistance index.

[0127] According to the first embodiment, the control function 351 controls to display the capillary resistance index calculated for each divided range in color and to display the assigned color image on the three-dimensional image showing the myocardial region or the coronary artery. Therefore, the medical information processing device 300 according to the first embodiment makes it possible to provide more easily understandable information about the capillary resistance index in each region.

[0128] According to the first embodiment, the control function 351 controls to display a display image showing the coronary artery on a two-dimensional plane along the long axis direction and a graph showing the change in the capillary resistance index calculated for each range of the coronary artery, with the positions in the display image corresponding to the positions in the graph. Therefore, the medical information processing device 300 according to the first embodiment makes it possible to more clearly display the relationship between the properties of the myocardium and the capillary resistance index.

[0129] According to the first embodiment, the control function 351 controls to display the result of myocardial perfusion on the display image. Therefore, the medical information processing device 300 according to the first embodiment makes it possible to provide more easily understandable information regarding the relationship between the myocardial blood flow rate and the capillary resistance index.

[0130] According to the first embodiment, the control function 351 controls to display the coronary arteries and myocardial region in a distinguishable manner on the display image in which the myocardium is displayed in polar coordinates, and to display a color image in which the index calculated for each divided range is indicated by color. Therefore, the medical information processing device 300 according to the first embodiment makes it possible to provide more easily understandable information about the capillary resistance index of the target region while allowing the user to grasp the entire myocardium.

[0131] According to the first embodiment, the control function 351 controls to display at least two of the following: a first color image in which the capillary resistance index calculated for each divided range is indicated by color and assigned to a three-dimensional image showing a myocardial region or a coronary artery; a display image showing the coronary artery on a two-dimensional plane along the long axis direction and a graph showing the change in the capillary resistance index calculated for each range of the coronary artery; and a second color image in which the coronary artery and the myocardial region are identifiable on a display image showing the myocardium in polar coordinates, and the capillary resistance index calculated for each divided range is indicated by color. Furthermore, the control function 351 controls to display at least two of the first color image, the display image and graph, and the second color image, which are displayed, with markers indicating approximately the same position. Therefore, the medical information processing device 300 according to the first embodiment can compare multiple display images to make a diagnosis, and can clarify the positional relationship between the multiple images. In addition, since it is possible to compare and observe the morphology of the myocardium and coronary artery with the capillary resistance index, it is possible to distinguish between ischemia and myocardial infarction and determine a treatment plan.

[0132] According to the first embodiment, the control function 351 controls to further display a short-axis cross-sectional image of the coronary artery at the position where the marker is placed on the coronary artery when the marker is placed on the coronary artery. Therefore, the medical information processing device 300 according to the first embodiment can provide more detailed morphological information.

[0133] According to the first embodiment, the control function 351 controls to superimpose a 3D image showing the coronary artery and a color image showing the capillary resistance index for each range in color on the 3D image showing the myocardial region, and further displays a marker indicating a position in the coronary artery and the fractional flow reserve at the position of the marker. Therefore, the medical information processing device 300 according to the first embodiment makes it possible to compare and observe the capillary resistance index and the FFR value.

[0134] According to the first embodiment, the control function 351 controls to display a three-dimensional image showing the coronary artery, a marker indicating a position in the coronary artery, and the capillary resistance index and the fractional flow reserve at the position of the marker. Therefore, the medical information processing device 300 according to the first embodiment makes it possible to compare and observe the capillary resistance index and the FFR value.

[0135] According to the first embodiment, the control function 351 controls to display the result of myocardial perfusion on a display image showing the myocardium in polar coordinates, and to identifiably display a region in the myocardial region included in the display image where the capillary resistance index is lower than a threshold. The control function 351 also controls to display the result of myocardial perfusion on a three-dimensional image showing the myocardium, and to identifiably display a region in the myocardial region included in the three-dimensional image where the capillary resistance index is lower than a threshold. Therefore, the medical information processing device 300 according to the first embodiment can comparatively observe the result of myocardial blood flow and the capillary resistance index, and therefore can identify the myocardial region that will be revived by reperfusion and determine a treatment plan.

[0136] According to the first embodiment, the control function 351 controls the display of a three-dimensional image showing a coronary artery, and when a designation operation for designating a position in the coronary artery relative to the three-dimensional image is received, the control function 351 controls the display of the fractional flow reserve at the received position, the result of myocardial perfusion in the myocardial region to which blood is supplied by the coronary artery at the received position, the capillary resistance index at the received position, and a value based on the pixel value at the received position, side by side. Also, the control function 351 controls the display of a three-dimensional image showing a myocardium, and when a designation operation for designating a myocardial region relative to the three-dimensional image is received, the control function 351 controls the display of the fractional flow reserve in the coronary artery supplying blood to the received myocardial region, the result of myocardial perfusion in the received myocardial region, and the index in the received myocardial region, side by side. Thus, the medical information processing device 300 according to the first embodiment makes it possible to identify the cause of ischemia that is difficult to determine based on only a specific index, and to determine a treatment plan.

[0137] According to the first embodiment, the control function 351 displays a recommended treatment plan for at least one of the accepted position and the accepted myocardial region based on a comparison result between each display item displayed side by side and a threshold value set for each display item. Therefore, the medical information processing device 300 according to the first embodiment makes it possible to support the decision of a treatment plan.

[0138] According to the first embodiment, the calculation function 354 calculates a capillary resistance index based on the ratio of the vascular blood flow rate to the myocardial blood flow rate. Therefore, the medical information processing device 300 according to the first embodiment makes it possible to easily provide an index for evaluating the resistance of the capillaries.

[0139] Second embodiment Although the first embodiment has been described above, the present invention may be embodied in various different forms other than the above-described first embodiment.

[0140] In the above embodiment, the capillary resistance index is calculated based on the ratio between the vascular blood flow and the myocardial blood flow. However, the embodiment is not limited to this, and may be calculated using two values, such as taking a logarithmic ratio or adding or multiplying a coefficient to the numerator or denominator.

[0141] For example, the blood flow velocity, blood viscosity, ejection fraction and ejection volume of the entire heart, etc. may be multiplied as correction coefficients. In such a case, the calculation function 354 acquires information on the flow velocity and viscosity from the results of the fluid analysis by the acquisition function 352. The calculation function 354 also calculates the ejection fraction and ejection volume of the entire heart based on time-course CT image data collected at multiple time phases for one or more heartbeats.

[0142] Here, when the calculation function 354 uses the blood flow velocity, for example, the blood flow velocity is used as a correction coefficient so that the capillary resistance index is lower when the flow velocity is high. When the calculation function 354 uses the blood viscosity, for example, the blood viscosity is used as a correction coefficient so that the capillary resistance index is lower when the viscosity is high. When the blood viscosity is used as a correction coefficient, for example, it is possible to calculate a change in myocardial blood flow when the blood viscosity is lowered due to improvement of lifestyle-related diseases. When the calculation function 354 uses the ejection fraction and ejection volume of the entire heart, for example, the ejection fraction and ejection volume of the entire heart are used as correction coefficients so that the capillary resistance index changes regularly with the change in the ejection fraction and ejection volume of the entire heart.

[0143] In the above embodiment, the case where information is displayed using the capillary resistance index as it is has been described. However, the embodiment is not limited to this, and for example, a value obtained by multiplying the capillary resistance index by another coefficient or the like may be used. As an example, the calculation function 354 may display the above-mentioned various display information using a value obtained by multiplying the calculated capillary resistance index by an index value indicating "ease of blood flow between cells". This makes it possible for the medical information processing device 300 to provide information indicating the myocardial infarction region and its progression.

[0144] In the above-described embodiment, the results of myocardial perfusion are used for the SPR image and the polar map. However, the embodiment is not limited to this, and other values ​​indicating myocardial function indexes may be used instead. For example, local movement of the myocardium may be extracted by performing ultrasonic imaging of the heart, and the magnitude of the movement may be used instead of the results of myocardial perfusion.

[0145] In addition, the medical information processing device 300 according to the present application can also perform machine learning using the calculated vascular blood flow rate and myocardial blood flow rate. For example, the medical information processing device 300 constructs a classifier by machine learning the relationship between the vascular blood flow rate and myocardial blood flow rate and the value of CFR in the target region. The constructed classifier outputs the value of CFR in response to the input of new vascular blood flow rate and myocardial blood flow rate. This makes it possible to estimate the CFR from the vascular blood flow rate and myocardial blood flow rate. In other words, it makes it possible to obtain the value of CFR while avoiding an increase in the amount of exposure and the administration of a vasodilator. In addition, in the above-mentioned machine learning, a value measured by a capillary resistance test or the like may be used instead of the CFR.

[0146] In the above-described embodiment, the medical information processing device 300 alone executes various processes. However, the embodiment is not limited to this. For example, the processing circuitry 350 may realize the functions by using a processor of an external device connected via a network. For example, the processing circuitry 350 reads out and executes a program corresponding to each function from the storage circuitry 320, and uses a server group (cloud) connected to the medical information processing device 300 via a network as a computational resource to realize each function shown in FIG. 1. For example, the storage circuitry 320 may be realized by a server group (cloud) connected to the medical information processing device 300 via a network.

[0147] In the above-described embodiment, an example in which each processing function is realized by a single processing circuit (processing circuit 350) has been described, but the embodiment is not limited to this. For example, the processing circuit 350 may be configured by combining multiple independent processors, and each processor may execute each program to realize each processing function. In addition, each processing function of the processing circuit 350 may be appropriately distributed or integrated and realized in a single or multiple processing circuits.

[0148] The term "processor" used in the description of each of the above-mentioned embodiments means, for example, a circuit such as a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC), a programmable logic device (for example, a simple programmable logic device (SPLD), a complex programmable logic device (CPLD), and a field programmable gate array (FPGA)). Here, instead of storing a program in a memory circuit, the program may be directly embedded in the circuit of the processor. In this case, the processor realizes its function by reading and executing the program embedded in the circuit. Furthermore, each processor in the present embodiment is not limited to being configured as a single circuit for each processor, and may be configured as a single processor by combining multiple independent circuits to realize its function.

[0149] Here, the program executed by the processor is provided in advance in a ROM (Read Only Memory), a storage circuit, or the like. The program may be provided by being recorded in a computer-readable storage medium such as a CD (Compact Disk)-ROM, a FD (Flexible Disk), a CD-R (Recordable), or a DVD (Digital Versatile Disk) in a format that can be installed in these devices or in a format that can be executed. The program may also be provided or distributed by being stored on a computer connected to a network such as the Internet and downloaded via the network. For example, the program is composed of modules including each of the functional units described below. As for actual hardware, a CPU reads out the program from a storage medium such as a ROM and executes it, so that each module is loaded onto a main storage device and generated on the main storage device.

[0150] According to at least one of the embodiments described above, an index capable of evaluating the resistance in capillaries can be provided.

[0151] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope of the invention and its equivalents described in the claims, as well as in the scope and spirit of the invention. [Explanation of symbols]

[0152] 300 Medical information processing device 351 Control Functions 352 Acquisition Function 353 Image Generation Function 354 Calculation Function 355 Judgment Function

Claims

1. An acquisition unit that acquires an index value relating to vascular blood flow in a coronary artery of a subject, the index value being estimated based on shape data of the coronary artery, and an index value relating to myocardial blood flow calculated based on a contrast image of a myocardial region to which blood is supplied by the coronary artery; a calculation unit that calculates a risk index related to the capillaries that supply the blood to the myocardial region based on a comparison between the index value related to the vascular blood flow and the index value related to the myocardial blood flow; A medical information processing device comprising:

2. A medical information processing device as described in claim 1, further comprising a display control unit that identifies a myocardial region corresponding to the capillary for which the risk index is calculated in a medical image including the myocardium, and controls the risk index to be displayed within the identified myocardial region.

3. A medical information processing device as described in claim 1, further comprising a display control unit that identifies a coronary artery region corresponding to the capillary for which the risk index is calculated in a medical image including the coronary artery, and controls the risk index to be displayed within the identified coronary artery region.

4. A medical information processing device as described in claim 1, further comprising a display control unit that controls the display of a graph showing changes in the risk index calculated for each range of the coronary artery together with a display image showing the coronary artery on a two-dimensional plane along its longitudinal axis.

5. The medical information processing device described in Claim 4, wherein the display control unit controls the display image to display an index value related to the myocardial blood flow.

6. A medical information processing device as described in claim 1, further comprising a display control unit that controls the coronary arteries and the myocardial region to be identifiable on a display image in which the myocardium is displayed in polar coordinates, and controls the risk index to be displayed within the myocardial region.

7. A medical information processing device as described in claim 1, further comprising a display control unit that controls the display of a three-dimensional image showing the coronary artery, a marker indicating a position in the coronary artery, and a numerical value of the risk index at the position of the marker.

8. A medical information processing device as described in claim 1, further comprising a display control unit that controls the display of an index value regarding the vascular blood flow rate in a coronary artery that supplies blood to the myocardial region and an index value of the risk index side by side.

9. A medical information processing device as described in claim 1, wherein the risk index corresponds to the resistance of the capillaries.

10. the acquiring unit acquires a plurality of index values ​​relating to vascular blood flow in a plurality of coronary arteries and a single index value relating to myocardial blood flow obtained by aggregating the index values ​​relating to myocardial blood flow in a plurality of myocardial regions respectively supplied with blood by the plurality of coronary arteries; The medical information processing apparatus according to claim 1 , wherein the calculation unit calculates the risk index by combining the index values ​​related to the plurality of vascular blood flow rates and the index value related to the single myocardial blood flow rate.

11. the acquiring unit acquires an index value related to vascular blood flow at an upstream end and an index value related to vascular blood flow at a downstream end of a range of a coronary artery that supplies blood to a myocardial region, and an index value related to myocardial blood flow in the myocardial region; The medical information processing device according to claim 1 , wherein the calculation unit calculates the risk index by combining a difference between an index value relating to vascular blood flow at the upstream end and an index value relating to vascular blood flow at the downstream end, and an index value relating to myocardial blood flow in the myocardial region.

12. the acquiring unit divides the coronary artery and the myocardial region to which blood is supplied by the coronary artery into a plurality of ranges, and acquires, for each divided range, an index value related to vascular blood flow at an upstream end of the range, an index value related to vascular blood flow at a downstream end of the range, and an index value related to myocardial blood flow in the myocardial region corresponding to the range; 2. The medical information processing device according to claim 1, wherein the calculation unit calculates the risk index for each of the divided ranges by combining a difference between an index value relating to vascular blood flow at the upstream end and an index value relating to vascular blood flow at the downstream end, and an index value relating to myocardial blood flow in a myocardial region corresponding to the range.

13. 2. The medical information processing device according to claim 1, further comprising a display control unit configured to control a display image showing information about the risk index calculated by the calculation unit to be displayed on a medical image including at least one of the myocardial region and the coronary artery.

14. The medical information processing device according to claim 12, further comprising a display control unit that controls to display the risk index calculated for each of the divided ranges in a color and to display a color image assigned to the color index on a three-dimensional image showing the myocardial region or the coronary artery.

15. The medical information processing device of claim 4, wherein the display control unit controls the display image and the graph to be displayed in correspondence with a position in the display image and a position in the graph.

16. 13. The medical information processing device according to claim 12, further comprising a display control unit that controls to display the coronary arteries and the myocardial region in an identifiable manner on a display image in which the myocardium is displayed in polar coordinates, and to display a color image in which the risk index calculated for each of the divided ranges is indicated by color.

17. a display control unit that controls to display at least two of a first color image that indicates the risk index calculated for each of the divided ranges in a color and that is assigned to a three-dimensional image showing the myocardial region or the coronary artery, a display image that shows the coronary artery on a two-dimensional plane along the longitudinal direction and a graph showing changes in the risk index calculated for each range of the coronary artery, and a second color image that displays the coronary artery and the myocardial region in a identifiable manner on a display image in which the myocardium is displayed in polar coordinates, and that indicates the risk index calculated for each of the divided ranges in a color; 13. The medical information processing device according to claim 12, wherein the display control unit controls to display at least two of the first color image, the display image and the graph, and the second color image, with markers indicating approximately the same position.

18. The medical image processing apparatus according to claim 17 , wherein the display control unit performs control such that, when the marker is placed on the coronary artery, a short-axis cross-sectional image of the coronary artery at the position where the marker is placed is further displayed.

19. 13. The medical information processing device according to claim 12, further comprising a display control unit that controls to superimpose a three-dimensional image showing the coronary artery and a color image showing the indicators for each range in color on the three-dimensional image showing the myocardial region, and to further display a marker indicating a position in the coronary artery and the fractional flow reserve at the position of the marker.

20. 13. The medical information processing device according to claim 12, further comprising a display control unit configured to control to display a three-dimensional image showing the coronary artery, a marker indicating a position in the coronary artery, and the risk index and fractional flow reserve at the position of the marker.

21. The medical information processing device according to claim 12, further comprising a display control unit that controls to display the results of myocardial perfusion on a display image in which the myocardium is displayed in polar coordinates, and to display in an identifiable manner a region in the myocardial region included in the display image in which the risk index is lower than a threshold value.

22. The medical information processing device according to claim 12, further comprising a display control unit that controls to display the results of myocardial perfusion on a three-dimensional image showing the myocardium and to identifiably display a region in the myocardial region included in the three-dimensional image in which the risk index is lower than a threshold value.

23. 13. The medical information processing device according to claim 12, further comprising a display control unit that controls, when a designation operation for designating a position in the coronary artery relative to the three-dimensional image is received, to display side by side the fractional coronary flow reserve at the accepted position, a result of myocardial perfusion in a myocardial region supplied with blood by the coronary artery at the accepted position, the risk index at the accepted position, and a value based on a pixel value at the accepted position.

24. 13. The medical information processing device according to claim 12, further comprising a display control unit that controls to display a three-dimensional image showing the myocardium, and when a designation operation for designating a myocardial region in the three-dimensional image is received, to display side by side a fractional flow reserve in a coronary artery supplying blood to the received myocardial region, a result of myocardial perfusion in the received myocardial region, and the risk index in the received myocardial region.

25. 25. The medical information processing device according to claim 23, wherein the display control unit displays a recommended treatment policy for at least one of the accepted position and the accepted myocardial region based on a comparison result between each display item displayed in a line and a threshold value set for each display item.

26. The medical information processing device according to claim 1 , wherein the calculation unit calculates the risk index based on a ratio between the index value relating to the vascular blood flow and the index value relating to the myocardial blood flow.

27. ​​Obtaining an index value relating to vascular blood flow in a coronary artery of a subject, the index value being estimated based on shape data of the coronary artery, and an index value relating to myocardial blood flow calculated based on a contrast image of a myocardial region to which blood is supplied by the coronary artery; calculating a risk index for the capillaries supplying the blood to the myocardial region based on a comparison between the index value for the vascular blood flow rate and the index value for the myocardial blood flow rate; A medical information processing program that causes a computer to execute each process.

28. An acquisition unit that acquires an index value relating to vascular blood flow in a coronary artery of a subject, the index value being estimated based on shape data of the coronary artery, and an index value relating to myocardial blood flow calculated based on a contrast image of a myocardial region to which blood is supplied by the coronary artery; a calculation unit that calculates a risk index related to the capillaries that supply the blood to the myocardial region based on a comparison between the index value related to the vascular blood flow and the index value related to the myocardial blood flow; A medical information processing system comprising:

29. Obtaining an index value relating to vascular blood flow in a coronary artery of a subject, the index value being estimated based on shape data of the coronary artery, and an index value relating to myocardial blood flow calculated based on a contrast image of a myocardial region to which blood is supplied by the coronary artery; calculating a risk index for the capillaries supplying the blood to the myocardial region based on a comparison between the index value for the vascular blood flow rate and the index value for the myocardial blood flow rate; A medical information processing method comprising:

30. An acquisition unit that acquires, in a first vascular region among blood vessels supplying blood to a subject's myocardium, an index value relating to vascular blood flow in the first vascular region estimated based on shape data of the blood vessels in the first vascular region, and an index value relating to myocardial blood flow calculated based on an image of the myocardial region to which blood is supplied by the blood vessels; a calculation unit that calculates a risk index for a second vascular region that receives blood from the first vascular region and supplies the blood to the myocardial region based on a comparison between the index value for the vascular blood flow rate and the index value for the myocardial blood flow rate; A medical information processing device comprising:

31. In a first vascular region of blood vessels supplying blood to the myocardium of a subject, an index value relating to vascular blood flow in the first vascular region estimated based on shape data of the blood vessels in the first vascular region, and an index value relating to myocardial blood flow calculated based on an image of the myocardial region to which blood is supplied by the blood vessel are obtained, calculating a risk index for a second vascular region that receives blood from the first vascular region and supplies the blood to the myocardial region based on a comparison between the index value for the vascular blood flow rate and the index value for the myocardial blood flow rate; A medical information processing program that causes a computer to execute each process.

32. An acquisition unit that acquires, in a first vascular region among blood vessels supplying blood to a subject's myocardium, an index value relating to vascular blood flow in the first vascular region estimated based on shape data of the blood vessels in the first vascular region, and an index value relating to myocardial blood flow calculated based on an image of the myocardial region to which blood is supplied by the blood vessels; a calculation unit that calculates a risk index for a second vascular region that receives blood from the first vascular region and supplies the blood to the myocardial region based on a comparison between the index value for the vascular blood flow rate and the index value for the myocardial blood flow rate; A medical information processing system comprising:

33. In a first vascular region of blood vessels supplying blood to the myocardium of a subject, an index value relating to vascular blood flow in the first vascular region estimated based on shape data of the blood vessels in the first vascular region, and an index value relating to myocardial blood flow calculated based on an image of the myocardial region to which blood is supplied by the blood vessel are obtained, calculating a risk index for a second vascular region that receives blood from the first vascular region and supplies the blood to the myocardial region based on a comparison between the index value for the vascular blood flow rate and the index value for the myocardial blood flow rate; A medical information processing method comprising:

Images