JP7024023B2 - Medical image processing equipment, medical image processing system and medical image processing method - Google Patents

Description

Embodiments of the present invention relate to a medical image processing apparatus.

Generally, in ischemic heart disease, blood flow to the myocardium is obstructed due to occlusion or stenosis of the coronary arteries, and the blood supply is insufficient or interrupted, resulting in heart damage. Symptoms include pain and pressure, mainly in the precordium, sometimes in the left arm and back. Treatment methods for patients with ischemic heart disease can be broadly classified into three types: bypass surgery, PCI (catheter surgery), and drug therapy.

Bypass surgery, as shown in FIG. 20, involves connecting other blood vessels to a narrowed or occluded blood vessel so that more blood flows through the ischemic site. It is a treatment method that is done in this way.

As shown in FIGS. 21 and 22, PCI is a treatment method in which a treatment instrument having a thin tubular structure is directly inserted into a blood vessel causing obstruction or stenosis to forcibly dilate the blood vessel.

Pharmacotherapy is a treatment that improves ischemia of the heart and prevents the formation of blood clots.

FFR (Fractional Flow Reserve) is an index of which of these three treatments a doctor chooses.

The degree of progression of stenosis is generally assessed by inserting a pressure wire directly into the blood vessel. The pressure wire is inserted as shown _in FIG. 23, and the pressure Pin and P _out before and after the narrowed portion are measured.

Here, _FFR is defined as P _out / Pin, and if this value is lower than 0.8, the doctor selects PCI as the treatment method, and if this value is higher than 0.8, the doctor selects drug therapy as the treatment method. select. However, since the measurement of pressure _Pin and P _out using the pressure wire is invasive, a non-invasive measurement method and an FFR estimation method are desired.

Therefore, in recent years, a simulation-based FFR estimation method using fluid analysis has been devised. The existing simulation is a simulation using a 3D image. As a basic concept of such a simulation-based FFR estimation method, the shape of a blood vessel acquired from a modality and physical parameters such as the viscosity value of blood etc. are used as inputs in, for example, CFD (Computational Fluid Dynamics). The FFR is estimated (calculated) using the Navier-Stokes equation.

The problem with such a 3D simulation is that it requires a large amount of calculation time. Therefore, it takes time to select a treatment method using FFR, and there is a disadvantage that it is not suitable when competing for the moment. Therefore, as an improvement measure, there is a method of significantly reducing the time required for the simulation by approximating the simulation using the 3D image in 2D.

This makes it possible to quickly calculate FFR on a simulation basis, and doctors can use FFR as a more effective index.

WO10 / 098444 Japanese Unexamined Patent Publication No. 2007-151881

Journal of Cardiovascular Computed Tomography-Min et al.-2011

However, at present, the causal relationship and risk evaluation between the ischemic myocardium and the stenosis to be treated have not been performed, that is, the FFR is appropriately reflected in the causal relationship and risk evaluation between the ischemic myocardium and the stenosis to be treated. It is not possible to do so, and the decision as to which stenosis should be treated with the highest priority depends largely on the doctor's empirical rules. Therefore, there is a disadvantage that human error may occur such as unnecessary treatment or oversight.

Further, for example, in the coronary arteries that contribute to myocardial infarction, the blood flow and pressure decrease, so that the above-mentioned FFR is apparently high. Therefore, FFR is apparently high even though it causes serious symptoms such as myocardial infarction. Even in such a case, there is an inconvenience that human error may occur, such as oversight of symptoms or mistake in selection of treatment method.

An object is to provide a medical image processing apparatus capable of reducing the possibility of human error.

The medical image processing apparatus according to the present embodiment includes a first acquisition unit, a calculation unit, a second acquisition unit, a first specific unit, a second specific unit, and a display unit. The first acquisition unit acquires a plurality of coronary arteries visualized in the image data regarding the heart, and acquires at least one stenosis site visualized in each acquired coronary artery. The calculation unit calculates the pressure difference of each acquired coronary artery based on the shape of the acquired plurality of coronary arteries. The second acquisition unit acquires the myocardial infarct region or ischemic region related to the heart depicted in the image. The first specific part refers to the controlled vessel relating the acquired myocardial infarction region or ischemic region to the control map relating each acquired coronary artery to the controlled region to determine the responsible vessel of the myocardial infarct region or ischemic region. Identify. The second specific part identifies the responsible stenosis based on the pressure gradient corresponding to the stenosis site in the identified responsible blood vessel. The display unit displays an image in which the specified responsibility stenosis is visualized together with information indicating the responsibility stenosis.

It is a schematic diagram which shows the structural example of the medical image processing system which includes the medical image processing apparatus which concerns on 1st Embodiment. It is a schematic diagram which shows an example of the territory map stored in the territory map storage part which concerns on 1st Embodiment. It is a flowchart which shows an example of the operation of the medical image processing apparatus which concerns on 1st Embodiment. It is a schematic diagram which shows an example of the analysis result by the coronary artery analysis part which concerns on 1st Embodiment. It is a schematic diagram which shows an example of the analysis result by the myocardial analysis part which concerns on 1st Embodiment. It is a schematic diagram which shows an example of the 3D image of the responsible blood vessel displayed by the display part which concerns on the same embodiment. It is a schematic diagram which shows an example of the 2D image of the responsible blood vessel displayed by the display part which concerns on 1st Embodiment. It is a schematic diagram which is the 2D image of the responsible blood vessel displayed by the display part which concerns on 1st Embodiment, and shows an example of the 2D image which suggests the priority of treatment. It is a schematic diagram which is the 2D image of the responsible blood vessel displayed by the display part which concerns on 1st Embodiment, and shows an example of the 2D image which suggests the priority of treatment. It is a 2D image of a responsible blood vessel displayed by the display part which concerns on 1st Embodiment, and is a schematic diagram which shows an example of the 2D image which suggests the existence of a collateral blood vessel. It is a 2D image of a responsible blood vessel displayed by the display part which concerns on 1st Embodiment, and is a schematic diagram which shows an example of the 2D image which suggests the size of a catheter stent. It is a schematic diagram which shows the structural example of the medical image system including the medical image processing apparatus which concerns on 2nd Embodiment. It is a flowchart which shows an example of the operation of the medical image processing apparatus which concerns on 2nd Embodiment. It is a schematic diagram which shows an example of the marker which shows the contour of the infarction responsible blood vessel generated by the marker generation part which concerns on 2nd Embodiment. It is a schematic diagram which shows an example of the marker which shows the transition of the FFR value generated by the marker generation part which concerns on 2nd Embodiment. It is a schematic diagram which shows an example of the 2D image of the infarction responsible blood vessel displayed by the display part which concerns on 2nd Embodiment. It is a schematic diagram which shows an example of the 3D image of the infarction responsible blood vessel displayed by the display part which concerns on 2nd Embodiment. It is a flowchart which shows an example of another operation of the medical image processing apparatus which concerns on 2nd Embodiment. It is a flowchart which shows an example of the operation of the medical image processing apparatus which concerns on 3rd Embodiment. It is a schematic diagram which shows an example of the 3D image of the infarction responsible blood vessel displayed by the display part which concerns on 3rd Embodiment. It is a schematic diagram for demonstrating the principle of bypass surgery. It is a schematic diagram for demonstrating the principle of catheter surgery for vascular stenosis. It is a schematic diagram for demonstrating the principle of balloon catheter surgery. It is a schematic diagram for demonstrating the method of inserting a pressure wire into a coronary artery.

[First Embodiment]
FIG. 1 is a schematic diagram showing a configuration example of a medical image processing system including the medical image processing apparatus according to the first embodiment, and FIG. 2 is a schematic diagram of a territory map stored in a territory map storage unit according to the same embodiment. It is a schematic diagram which shows an example. In the medical image processing system 1 shown in FIG. 1, the medical image processing device 10, the CT (Computed Tomography) device 20 and the PACS (Picture Archiving and Communication System) 30 are, for example, a LAN (Local Area Network) or a public electronic communication line. It is a system connected so as to be communicable via the network 40 such as. Therefore, the medical image processing device 10 is provided with a communication interface 103 that enables communication with the CT device 20 and the PACS 50.

As shown in FIG. 1, the medical image processing apparatus 10 includes an image storage unit 101, a territory map storage unit 102, a communication interface 103, a control unit 104, a heart region extraction unit 105, a myocardial analysis unit 106, a coronary artery analysis unit 107, and a responsibility. It includes a blood vessel identification unit 108, an FFR calculation unit 109, a responsible stenosis identification unit 110, a marker generation unit 111, and a display unit 112. Hereinafter, the functions of the respective parts 101 to 112 constituting the medical image processing apparatus 10 will be described in detail.

The image storage unit 101 is a time-series three-dimensional contrast CT image data (hereinafter referred to as a time-series three-dimensional contrast CT image data) relating to the chest region including the heart of the subject as a processed image transmitted from the CT device 20 or the PACS 50 under the control unit 104. , Simply referred to as volume data).

As shown in FIG. 2, the territory map storage unit 102 is a storage device that stores a territory map (hereinafter referred to as a control map) that defines the relationship between the coronary arteries and the controlled area to which nutrition is supplied by each coronary artery.

The heart region extraction unit 105 extracts the heart region from the volume data by a heart contour extraction process or the like.

The myocardial analysis unit 106 extracts the myocardial region from the cardiac region extracted by the cardiac region extraction unit 105 by threshold processing or the like based on the CT value corresponding to the contrast medium concentration. Further, the myocardial analysis unit 106 generates a time concentration curve for the contrast medium for each pixel or each region in the extracted myocardial region, that is, for myocardial perfusion analysis, and for each pixel or each region based on the time concentration curve. The amount of blood flow that moves during the period from the inflow of the contrast medium to the outflow is calculated.

For example, in imaging using a CT device, a nonionic contrast medium can be injected into a patient, and perfusion information of an organ can be visualized from a change in CT value. Therefore, in the CT perfusion analysis, for example, the change with time of the CT image (volume data) composed of 512 × 512 pixels can be measured from the change of the CT value in each pixel, and the blood flow rate and the like can be quantified. .. In this way, one color map showing the perfusion information (for example, blood flow) of the organ is generated from the CT images of the plurality of time phases.

Further, the myocardial analysis unit 106 identifies the ischemic region by threshold processing from the calculated spatial distribution of blood flow.

The coronary artery analysis unit 107 extracts a plurality of coronary arteries from the heart region extracted by the cardiac region extraction unit 105, and further extracts at least one stenosis site from each of the extracted coronary arteries. Specifically, the coronary artery analysis unit 107 analyzes the anatomical structure and plaque properties of the coronary arteries along the core line of the coronary arteries, the inner wall of the blood vessels, and the like, and extracts volume data related to the coronary arteries, that is, the coronary arteries and the coronary arteries thereof. Extract the stenotic site located on the inner wall of the coronary artery. Specific examples of the plaque properties include the amount of lipid, serum cholesterol concentration, hardness, degree of calcification, thickness of fibrous film (Thin-cap), and FFR value (however, in this embodiment, the FFR value is It shall be calculated by the FFR calculation unit 109) and the like.

The responsible blood vessel identification unit 108 inherently takes responsibility for supplying nutrients to the ischemic region by inquiring the control map stored in the territory map storage unit 102 for the ischemic region identified by the myocardial analysis unit 106. Identify the blood vessels that you have (hereinafter referred to as the responsible blood vessels).

The FFR calculation unit 109 calculates the FFR value corresponding to each stenosis site extracted by the coronary artery analysis unit 107 on a simulation basis. Specifically, first, the FFR calculation unit 109 performs each stenosis site extracted by the coronary artery analysis unit 107 at at least one position downstream of each stenosis site based on the color map generated by the myocardial analysis unit 106. Tissue blood flow and tissue blood flow at at least one location upstream of each stenosis site are calculated. Then, the FFR calculation unit 109 calculates the FFR value at least at each position including the stenosis site by dividing the calculated tissue blood flow downstream of the stenosis site by the calculated tissue blood flow upstream of the stenosis site. In the present embodiment, the FFR calculation unit 109 calculates the FFR value by the calculation method as described above, but the calculation method of the FFR value is not limited to this, and corresponds to each stenosis site. If the FFR value can be calculated, it can be appropriately applied as a method for calculating the FFR value used in the FFR calculation unit 109.

The responsible stenosis specifying unit 110 is a stenosis site located on the inner wall of the responsible blood vessel identified by the responsible blood vessel specifying unit 108 among the stenosis sites extracted by the coronary artery analysis unit 107 (hereinafter referred to as responsible stenosis), that is, responsible. Among the stenosis candidates, the stenosis site whose FFR value is less than the threshold is specified as responsible stenosis.

The marker generation unit 111 is extracted by the responsible blood vessel specified by the responsible blood vessel identification unit 108, the responsible stenosis specified by the responsible stenosis identification unit 110, the FFR value calculated by the FFR calculation unit 109, and the coronary artery analysis unit 107. Generates marker data that represents candidates for responsible stenosis. These markers are superimposed on a three-dimensional image generated by rendering or the like from volume data or a two-dimensional image generated by cross-section transformation (Multi-Planar Reconstruction), and are displayed on the display unit 112. The image on which the marker generated from the marker generation unit 111 is superimposed is not limited to the image derived from the volume data obtained by the CT device 20, but is an image acquired from another modality such as an X-ray diagnostic device. You may.

Here, an example of the operation of the medical image processing apparatus 10 according to the present embodiment will be described with reference to the schematic views of FIGS. 2 and 4 to 7 and the flowchart shown in FIG.

First, when the control unit 104 receives an input of time-series volume data over a plurality of time phases relating to the chest region from the CT device 20 or the PACS 50 via the communication interface 103, the control unit 104 stores the volume data for which the input is received in the image storage unit. Write in 101 (step S1).

Subsequently, the heart region extraction unit 105 reads volume data of a specific time phase with relatively few beats from the image storage unit 101 as a processed image under the control unit 104, and extracts the heart region from the volume data (step). S2).

Next, the coronary artery analysis unit 107 executes the coronary artery analysis process for the cardiac region extracted by the cardiac region extraction unit 105 (steps S3 and S4). Specifically, the coronary artery analysis unit 107 analyzes the anatomical structure and plaque properties of the coronary artery along the blood vessel core line and the inner wall of the coronary artery, and extracts the stenosis site located on the coronary artery and the inner wall of the coronary artery. do. After that, the coronary artery analysis unit 107 superimposes the anatomical structure of the coronary artery on the heart morphology image as a three-dimensional image g1 or a two-dimensional image g2, for example, as shown in FIGS. 4 (a) and 4 (b). It is displayed on the display unit 112. The timing for displaying the images g1 and g2 shown in FIGS. 4A and 4B on the display unit 112 can be arbitrarily set by the operator, that is, they may be displayed during processing. , May be displayed together with the processing result.

Subsequently, the myocardial analysis unit 106 extracts the myocardial region from the cardiac region extracted by the cardiac region extraction unit 105 by the threshold processing based on the CT value corresponding to the contrast medium concentration (step S5).

Next, the myocardial analysis unit 106 executes the CT perfusion analysis process only for the extracted myocardium (steps S6, S7, S8). Specifically, the myocardial analysis unit 106 generates a time concentration curve for the contrast medium for each pixel or each region in the extracted myocardial region based on the time-series volume data. After that, the myocardial analysis unit 106 calculates the blood flow rate that moves during the period from the inflow of the contrast medium to the outflow of the contrast medium for each pixel or each region based on the time concentration curve. As a result, for example, as shown in FIG. 5, a color map g3 showing the spatial distribution of blood flow is generated. Then, the myocardial analysis unit 106 identifies a region less than a predetermined blood flow as an ischemic region based on the generated color map g3, that is, the calculated spatial distribution of blood flow.

Subsequently, the responsible blood vessel identification unit 108 inquires about the control map stored in the territory map storage unit 102 for the ischemic region identified by the myocardial analysis unit 106, as shown in FIG. Identify the responsible vessel (step S9).

Next, the FFR calculation unit 109 is located downstream of each stenosis site based on the color map g3 generated by the myocardial analysis unit 106 for each stenosis site located on the inner wall of the responsible blood vessel specified by the responsible blood vessel identification unit 108. The tissue blood flow of the stenosis site and the tissue blood flow upstream of each stenosis site are calculated. Then, the FFR calculation unit 109 calculates the FFR value at least at each position including the stenosis site by dividing the calculated tissue blood flow downstream of the stenosis site by the calculated tissue blood flow upstream of the stenosis site. Step S10).

Subsequently, the responsible stenosis specifying unit 110 identifies the stenosis site where the FFR value calculated by the FFR calculation unit 109 is less than the threshold value as the responsible stenosis (step S11).

After that, as shown in FIGS. 6 and 7, the display unit 112 displays a marker representing the responsible blood vessel, the responsible stenosis, and the FFR value generated by the marker generating unit 111 as a three-dimensional image g4 or two-dimensional derived from the volume data. It is superimposed on the image g5 and displayed (step S12).

According to the above-described embodiment, the cardiac region extraction unit 105, the myocardial analysis unit 106, and the coronary artery analysis unit 107, which can extract the cardiac region, myocardial region, coronary artery, and stenotic region from the volume data obtained by the CT apparatus 20, and the coronary artery analysis unit 107, and myocardial analysis. Responsible stenosis identification unit 108 that identifies responsible stenosis based on the processing results by unit 106, and responsible stenosis identification unit that identifies responsible stenosis based on the processing results by coronary artery analysis unit 107, responsible blood vessel identification unit 108, and FFR calculation unit 109. With a configuration including 110 and a display unit 112 that superimposes and displays a marker related to a responsible blood vessel or a responsible stenosis on a three-dimensional image or a two-dimensional image derived from volume data, for example, as shown in FIG. 6, the responsible stenosis and control. The correspondence with the region can be visually shown to the doctor, and thus the possibility of human error can be reduced.

Further, in the present embodiment, the FFR calculation unit 109 calculates the FFR value on a simulation basis, that is, since a pressure wire or the like that has invasiveness is not used, the burden on the patient at the time of examination can be reduced.

In the present embodiment, FIGS. 6 and 7 are shown as an example of the image displayed by the display unit 112, but the image displayed by the display unit 112 is not limited to these, and for example, FIGS. 8A and 8B. The images g6 and g7 as shown in the above may be displayed. 8A and 8B show an example of images g6 and g7 in which the treatment priority of the stenosis site is ranked based on the FFR value calculated by the FFR calculation unit 109 and the processing result is superimposed as a marker. Here, the stenosis site having a higher treatment priority has a larger marker (circle) indicating the stenosis site. Further, FIG. 8A shows an example of the image g6 in which a bar graph showing the analysis result of the plaque property by the coronary artery analysis unit 107 is superimposed as a marker in addition to the priority. In addition to the analysis result of plaque properties, blood properties and the like may be further superimposed as markers on the image g6 shown in FIG. 8A. Further, when there are a plurality of responsible blood vessels, the display unit 112 can display an image on which the treatment result is superimposed as a marker after prioritizing the treatment of the stenotic site over the plurality of responsible blood vessels.

Further, according to the medical image processing apparatus 10 according to the present embodiment, whether or not the region of another artery overhangs a part of the region to be supplied by one artery at the time of inquiring the control map by the responsible blood vessel identification unit 108. It can also be suggested that there is a possibility of blood supply by the collateral vessels if it is detected that the area of another artery is overhanging. In general, the presence of collateral blood vessels reduces the reliability of the FFR value. Therefore, for example, as shown in FIG. 9, by displaying the image g8 suggesting the presence of collateral blood vessels on the display unit 112, a more human error occurs. The possibility of

Further, according to the medical image processing apparatus 10 according to the present embodiment, after the responsible stenosis is specified by the responsible stenosis specifying unit 110, the diameter and length of the cross section of the responsible stenosis are measured from the two-dimensional image derived from the volume data. , It is also possible to suggest the optimal catheter / stent size based on this measurement result. Specifically, for example, as shown in FIG. 10, by displaying the image g9 suggesting the optimum catheter / stent size on the display unit 112, the possibility of human error can be further reduced.

Further, according to the medical image processing apparatus 10 according to the present embodiment, when the myocardial analysis unit 106 indicates that there are a plurality of ischemic regions, the thickness of the myocardium and the like are measured from the volume data, and this measurement is performed. Based on the results, it is possible to add a setting that the blood vessel corresponding to the controlled area of the necrotic myocardium is not specified as the responsible blood vessel.

Further, according to the medical image processing apparatus 10 according to the present embodiment, when a desired three-dimensional image is displayed by the display unit 112, a responsible blood vessel or a responsible stenosis is selected from an input interface (not shown) such as a mouse, a keyboard, or a touch panel. Upon receiving the input to the effect, it is possible to automatically rotate the three-dimensional image to an angle at which the selected responsible blood vessel or responsible stenosis can be easily observed.

[Second Embodiment]
FIG. 11 is a schematic diagram showing a configuration example of a medical image processing system including the medical image processing device according to the second embodiment. The medical image processing system 1 shown in FIG. 11 includes a medical image processing device 10, a CT (Computed Tomography) device 20, an MRI (Magnetic Resonance Imaging) device 30, a nuclear medicine diagnostic device 40, and a PACS (Picture Archiving and Communication System) 50. Is a system that is communicably connected via a network 60 such as a LAN (Local Area Network) or a public electronic communication line. Therefore, the medical image processing device 10 is provided with a communication interface 103 that enables communication with the CT device 20, the MRI device 30, the nuclear medicine diagnostic device 40, and the PACS 50.

As shown in FIG. 11, the medical image processing apparatus 10 includes an image storage unit 101, a territory map storage unit 102, a communication interface 103, a control unit 104, a heart region extraction unit 105, a myocardial analysis unit 106, a coronary artery analysis unit 107, and a responsibility. It includes a blood vessel identification unit 108, an FFR calculation unit 109, a marker generation unit 111, and a display unit 111. Only the configuration different from the medical image processing apparatus 1 shown in the first embodiment will be described below.

The image storage unit 101 stores time-series three-dimensional contrast CT image data relating to the chest region including the heart of the subject as a processed image transmitted from the CT device 20 or PACS 50 under the control unit 104. It is a storage device.

As shown in FIG. 2, the territory map storage unit 102 is a storage device that stores a territory map that defines the relationship between the coronary arteries and the area controlled by each coronary artery.

The heart region extraction unit 105 extracts the heart region from the volume data by a heart contour extraction process or the like.

The myocardial analysis unit 106 extracts the myocardial region from the cardiac region extracted by the cardiac region extraction unit 105 by threshold processing or the like based on the CT value corresponding to the contrast medium concentration. In addition, the myocardial analysis unit 106 is a myocardial region that is necrotic among the myocardial regions extracted by delayed imaging (late gadolinium enhancement) by the MRI apparatus 30, glucose metabolism measurement by the nuclear medicine diagnostic apparatus 40, or the like, that is, myocardial infarction. Identify the area of myocardial infarction that contributes to.

Further, the myocardial analysis unit 106 calculates the myocardial perfusion analysis, that is, the amount of blood flow that moves during the period from the inflow to the outflow of the contrast medium for each pixel or local area in the extracted myocardial region. For example, in imaging using a CT device 20, a nonionic contrast medium can be injected into a patient, and perfusion information of an organ can be visualized from a change in CT value. Therefore, in the CT perfusion analysis, for example, the change with time of the CT image (volume data) composed of 512 × 512 pixels can be measured from the change of the CT value in each pixel, and the blood flow rate and the like can be quantified. .. In this way, one color map showing the perfusion information (for example, blood flow) of the organ is generated from the CT images of the plurality of time phases.

That is, the myocardial analysis unit 106 can not only specify the myocardial infarction region, but also, for example, identify the blood flow lowering site, that is, the ischemic region by thresholding from the calculated spatial distribution of blood flow.

The coronary artery analysis unit 107 extracts a plurality of coronary arteries from the heart region extracted by the cardiac region extraction unit 105, and further extracts at least one stenosis site from each of the extracted coronary arteries. Specifically, the coronary artery analysis unit 107 analyzes the anatomical structure and plaque properties of the coronary arteries along the core line of the coronary arteries, the inner wall of the blood vessels, and the like, and extracts volume data related to the coronary arteries, that is, the coronary arteries and the coronary arteries thereof. Extract the stenotic site located on the inner wall of the coronary artery. The plaque properties include the amount of lipid, serum cholesterol concentration, hardness, lime content, thickness of fibrous film (Thin-cap), and the like.

The responsible blood vessel identification unit 108 inherently takes responsibility for supplying nutrients to the myocardial infarction region by inquiring the control map stored in the territory map storage unit 102 for the myocardial infarction region identified by the myocardial infarction region 106. Identify the blood vessels that have (hereinafter referred to as infarction responsible blood vessels).

When the ischemic region is specified instead of the myocardial infarction region by the myocardial analysis unit 106, the responsible blood vessel identification unit 108 uses the territory map storage unit 102 for the ischemic region specified by the myocardial analysis unit 106. By inquiring the control map stored in the ischemic region, the blood vessels that are originally responsible for supplying nutrients to the ischemic region (hereinafter referred to as ischemic responsible blood vessels) are identified.

The FFR calculation unit 109 calculates FFR values for a plurality of positions including at least a stenotic site on each coronary artery extracted by the coronary artery analysis unit 107 on a simulation basis. Specifically, first, the FFR calculation unit 109 determines the tissue blood flow and the stenosis site in the coronary artery at at least one position downstream of the stenosis site in the coronary artery based on the color map generated by the myocardial analysis unit 106. Tissue blood flow is calculated at at least one position upstream of. Then, the FFR calculation unit 109 calculates the FFR value at least at each position including the stenosis site by dividing the calculated tissue blood flow downstream of the stenosis site by the calculated tissue blood flow upstream of the stenosis site. Here, the case of calculating the FFR value corresponding to one stenosis site in the coronary artery has been described. For example, when calculating the FFR value of the entire coronary artery, the upstream of the stenosis site located at the most upstream in the coronary artery. The tissue blood flow in the coronary artery is fixed as a reference value, and the tissue blood flow in other multiple locations (provided that the FFR calculation unit 109 calculates the tissue blood flow in multiple locations in the coronary artery) is used as a variable. Then, the FFR calculation unit 109 can calculate the FFR value corresponding to the plurality of locations, that is, the FFR value of the entire coronary artery.

The marker generation unit 111 generates data of the infarction-responsible blood vessel (or ischemia-responsible blood vessel) specified by the responsible blood vessel identification unit 108 and the marker (mark) representing the FFR value calculated by the FFR calculation unit 109. These markers are superimposed on a three-dimensional image generated by rendering or the like from volume data or a two-dimensional image generated by cross-section transformation (Multi-Planar Reconstruction), and are displayed on the display unit 111. The image on which the marker generated from the marker generation unit 111 is superimposed is not limited to the image derived from the volume data obtained by the CT device 20, but is an image acquired from another modality such as an X-ray diagnostic device. You may.

Here, an example of the operation of the medical image processing apparatus 10 according to the present embodiment will be described with reference to the schematic views of FIGS. 2, 13 to 16 and the flowchart of FIG. 12.

However, here, it is assumed that the image storage unit 101 stores in advance time-series volume data relating to the chest region from the CT device 20 or the PACS 50 over a plurality of time phases. Further, here, the heart region extraction unit 105 reads volume data of a specific time phase with relatively little beat under the control unit 104 as a processed image from the image storage unit 101, and has already extracted the heart region from the volume data. It is assumed that you are doing.

First, the coronary artery analysis unit 107 executes a coronary artery analysis process for the cardiac region extracted by the cardiac region extraction unit 105 (step S21). Specifically, the coronary artery analysis unit 107 analyzes the anatomical structure and plaque properties of the coronary artery along the blood vessel core line and the inner wall of the coronary artery, and extracts the stenosis site located on the coronary artery and the inner wall of the coronary artery. do.

Subsequently, the myocardial analysis unit 106 extracts the myocardial region from the cardiac region extracted by the cardiac region extraction unit 105 by the threshold processing based on the CT value corresponding to the contrast medium concentration. After that, the myocardial analysis unit 106 is a myocardial region that is necrotic among the myocardial regions extracted by delayed imaging by the MRI apparatus 30, glucose metabolism measurement by the nuclear medicine diagnostic apparatus 40, or the like, that is, myocardial infarction that contributes to myocardial infarction. The region is specified (steps S22, S23, S24).

Next, the responsible blood vessel identification unit 108 was extracted by the coronary artery analysis unit 107 by inquiring the control map stored in the territory map storage unit 102 for the myocardial infarction region identified by the myocardial infarction unit 106. The infarct responsible vessel is identified from each coronary artery (step S25).

Subsequently, the marker generation unit 111 generates marker data representing the infarction responsible blood vessel specified by the responsible blood vessel identification unit 108 (step S26). Specifically, the marker generation unit 111 generates a marker m1 representing the contour of the infarct-responsible blood vessel, for example, as shown in FIG.

Next, the FFR calculation unit 109 calculates the FFR value of the entire coronary artery for each coronary artery extracted by the coronary artery analysis unit 107 (step S27).

Subsequently, the marker generation unit 111 generates a marker representing the FFR value corresponding to each coronary artery calculated by the FFR calculation unit 109 (step S28). Specifically, the marker generation unit 111 generates a marker m2 representing a transition of the FFR value of each coronary artery, for example, as shown in FIG.

After that, as shown in FIG. 15, for example, the display unit 111 derives the marker m1 representing the infarct-responsible blood vessel generated by the marker generating unit 111 and the marker m2 representing the transition of the FFR value of each coronary artery from the volume data2. It is superimposed and displayed on the dimensional image g1 (step S29). The image displayed by the display unit 111 is not limited to the above-mentioned two-dimensional image g1, but as shown in FIG. 16, for example, a marker is attached to a three-dimensional image g2 derived from volume data and an image acquired from another modality. It may be a superimposed image.

In the description of the above operation example, the case where the responsible blood vessel specifying portion 108 specifies the infarction responsible blood vessel has been described. However, as shown in the flowchart of FIG. 17, for example, the responsible blood vessel specifying portion 108 identifies the ischemic responsible blood vessel. Even in this case, the medical image processing apparatus 10 identifies the ischemic region by myocardial perfusion analysis by the CT apparatus 20 or the MRI apparatus 30, a SPECT examination by the nuclear medicine diagnostic apparatus 40, or the like (steps S22', S23', S24'), the ischemic responsible blood vessel is identified from the specified ischemic region (step S25'), and a marker representing the specified ischemic responsible blood vessel is generated (step S26'). It works in the same way.

According to the second embodiment described above, the cardiac region extraction unit 105, the myocardial analysis unit 106, and the coronary artery analysis capable of extracting the cardiac region, myocardial region, coronary artery, stenosis site, and myocardial infarction region from the volume data obtained by the CT device 20. The volume data derives from the volume data of the unit 107, the responsible blood vessel identification unit 108 that identifies the infarction-responsible blood vessel based on the processing result by the myocardial analysis unit 106, the infarction-responsible blood vessel, and the marker representing the FFR value calculated by the FFR calculation unit 109. It is presented to the doctor that the reliability of the FFR value of the portion where the marker representing the infarct-responsible blood vessel is superimposed and displayed is low due to the configuration including the display unit 111 which is superimposed and displayed on the two-dimensional image or the three-dimensional image. be able to.

Further, in the present embodiment, the FFR calculation unit 109 calculates the FFR value on a simulation basis, that is, since a pressure wire or the like that has invasiveness is not used, the burden on the patient at the time of examination can be reduced.

[Third Embodiment]
Next, the medical image processing apparatus according to the third embodiment will be described with reference to FIG. 11 described above. In the present embodiment, the medical image processing apparatus 10 shown in the second embodiment is provided with a function of determining whether the stenosis site in the coronary artery is a treatment target stenosis or a treatment non-target stenosis. In the following, only the functions different from those of the second embodiment will be described with reference to the flowchart of FIG. 18 and the schematic diagram of FIG. That is, since the processing of steps S21 to S28 is the same as that of the second embodiment described above, detailed description thereof will be omitted here, and the processing of steps S30 to S36 will be mainly described below.

The coronary artery analysis unit 107 determines whether or not the stenosis site is a stenosis located in the infarct-responsible blood vessel for each stenosis site extracted in the process of step S21 (step S30).

When the result of the determination by the process of step S30 indicates that the stenosis is located in the blood vessel responsible for infarction (Yes in step S30), the myocardial analysis unit 106 is in the myocardial infarction region specified in the process of step S24. It is determined whether or not there is a living myocardium (step S31). Specifically, the myocardial analysis unit 106 determines whether or not the myocardial infarction region has reached half the thickness of the myocardium from delayed imaging by the MRI apparatus 30, and the result of the determination has arrived. If it indicates that there is a living myocardium, it is considered that there is no living myocardium, and if the result of the determination indicates no, it is considered that there is a living myocardium. If the result of the determination in the process of step S31 indicates no (No in step S31), the process proceeds to the process of step S35 described later.

When the result of the determination by the process of step S31 indicates that there is a living myocardium (Yes in step S31), the marker generating portion 111 includes a marker indicating an infarct-responsible blood vessel having a living myocardium and a marker indicating a stenosis to be treated. Is generated (step S32). Specifically, as shown in FIG. 19, for example, the marker generation unit 111 generates a marker m3 representing the contour of an infarct-responsible blood vessel having a living myocardium and a marker m4 representing a stenosis to be treated.

Here, when the result of the determination by the process of step S30 indicates no (No of step S30), the coronary artery analysis unit 107 determines the stenosis site among the FFR values of each coronary artery calculated in the process of step S27. It is determined whether or not the corresponding FFR value is equal to or less than the threshold value (step S33).

When it indicates that the result of the determination by the process of step S33 is equal to or less than the threshold value (Yes in step S33), the marker generating unit 111 generates a marker representing the stenosis to be treated (step S34). That is, the marker generation unit 111 generates a marker corresponding to the marker m4 shown in FIG.

When the result of the determination by the process of step S33 indicates no (No in step S33), the marker generating unit 111 generates a marker representing the treatment non-target stenosis (step S35). Specifically, the marker generation unit 111 generates a marker m5 representing a treatment non-target stenosis, for example, as shown in FIG.

After that, the display unit 111 includes a marker m1 representing the infarction-responsible blood vessel generated by the marker-generating part 111, a marker m2 representing the transition of the FFR value of each coronary artery, a marker m3 representing the infarction-responsible blood vessel having a living myocardium, and a stenosis to be treated. The marker m4 representing the above and the marker m5 representing the non-target stenosis for treatment are superimposed and displayed on the three-dimensional image g3 derived from the volume data (step S36). The image displayed by the display unit 111 may be not only the above-mentioned three-dimensional image g3, but also a two-dimensional image derived from volume data or an image in which a marker is superimposed on an image acquired from another modality. .. Further, when both the marker m1 representing the infarct-responsible blood vessel and the marker m3 representing the infarction-responsible blood vessel having the living myocardium are superimposed on the same position on the image, the marker m3 is preferentially displayed.

According to the third embodiment described above, myocardial analysis determines whether or not there is a living myocardium in the myocardial infarct region, and whether the stenosis site in the coronary artery is a stenosis to be treated or a stenosis not to be treated. A marker representing an infarct-responsible blood vessel having a living myocardium, a marker representing a stenosis to be treated, and a marker representing a stenosis not to be treated are used as a three-dimensional image or a two-dimensional image derived from volume data. With the configuration including the display unit 111 for superimposed display, more information can be presented to the doctor as compared with the first embodiment.

According to at least one of the second and third embodiments described above, the doctor determines that the reliability of the FFR value is low, the presence or absence of a living myocardium, and whether or not the stenosis site is a stenosis suitable for treatment. Since it can be presented to, the possibility of human error can be reduced.

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 novel embodiments can be implemented in various other embodiments, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and variations thereof are included in the scope and gist of the invention, and are also included in the scope of the invention described in the claims and the equivalent scope thereof.

1 ... Medical image processing system, 10 ... Medical image processing device, 20 ... CT device, 30 ... PACS, 40 ... Network, 101 ... Image storage unit, 102 ... Territory map storage unit, 103 ... Communication interface, 104 ... Control unit, 105 ... Cardiac region extraction unit, 106 ... Myocardial analysis unit, 107 ... Coronary artery analysis unit, 108 ... Responsible blood vessel identification unit, 109 ... FFR calculation unit, 110 ... Responsible stenosis identification unit, 111 ... Marker generation unit, 112 ... Display unit.

Claims (1)

An acquisition unit that acquires the shape of the coronary artery depicted in the image data of the heart and extracts the stenosis site located on the inner wall of the coronary artery .
A calculation unit that calculates the spatial distribution of FFR of the coronary artery based on the acquired shape of the coronary artery and physical parameters including the viscosity value of blood flowing through the coronary artery.
Based on the comparison between the FFR value and the threshold value, the responsible stenosis among the extracted stenosis sites is identified, a two-dimensional image including the responsible stenosis is generated, and the diameter of the cross section of the responsible stenosis is generated from the two-dimensional image. And an analysis unit that measures the length and identifies the size of the stent based on the measurement results .
A display unit that displays the size of the specified stent, and
A medical image processing device comprising.

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