JP2011036458A - Medical image display device, and medical image display method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a medical image display device, and a medical image display method reducing work quantity of doctors, improving throughput, facilitating determining whether or not CAS is applicable before an operation, and obtaining necessary image data for creating low invasive images to an examinee by automatically generating and displaying images indicating a P/M ratio and length of constriction as risk factors for embolic complication. <P>SOLUTION: The device includes: an image data analysis means 10 including an extraction processing means 12 to extract a blood vessel region, a blood vessel inner cavity region, a plaque region, and a muscle region by use of image data obtained by photographing an examinee, a measurement and computation processing means 13 to determine the P/M ratio by use of plaque region inner signal values and muscle region inner signal values, and measure the length of constriction in the blood vessel by use of the blood vessel region, the blood vessel inner cavity region and the plaque region, and a determination means 14 to determine whether or not there are risk factors based on information of the P/M ratio and the length of constriction; and a display means 1g displaying results of analysis by the image data analysis means. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a medical image display device and a medical image display method for supporting preoperative treatment selection by processing and displaying an image inside a subject photographed by an image generation device.

  2. Description of the Related Art In recent years, medical image display apparatuses that collect information inside a subject and generate and display a medical image by imaging the inside of the subject based on the collected image data have been used. Patent Document 1 shown below shows one method of use when this medical image display device is used, for example, in the treatment of carotid artery stenosis.

  The invention disclosed in Patent Document 1 automatically evaluates changes in the characteristics of coronary plaque lesions over time in longitudinal examinations for the purpose of evaluating changes in disease due to treatment for carotid artery stenosis, patient behavior correction, or continuous management. Tracking and detection.

  Examples of the treatment for carotid artery stenosis include carotid endarterectomy, which is a surgical operation, and carotid artery stenting (CAS), which is an endovascular treatment. The invention as disclosed in Patent Document 1 is disclosed because CAS is attracting attention because it places less burden on patients (subjects) during treatment.

  By the way, although this CAS is minimally invasive, it has been pointed out that a fragment (debris) such as plaque scattered during the operation may move to a peripheral blood vessel and cause a distal embolism (embolization complication). Peripheral vascular protection devices such as balloons and filters are used to prevent distal emboli. However, when using a filter capable of performing a procedure while maintaining blood flow in the brain, if the size of the debris is less than the size of the filter hole, the filter may pass through the filter. From this, it is pointed out that the effect of preventing embolic complications is not certain.

  Risk factors that are highly related to embolic complications include “P / M ratio” and “stenosis length”. The “P / M ratio” is a signal of a muscle adjacent to a signal value in the plaque region when using a Black Blood T1-weighted image in preoperative MRI (magnetic resonance imaging) image diagnosis. It is the ratio to the value. Further, the “stenosis length” is a length indicating a region showing a high stenosis rate along the longitudinal direction of the blood vessel due to plaque present in the blood vessel. Therefore, it can be said that these “P / M ratio” and “stenosis length” are suitable guidelines for determining the presence or absence of embolic complications.

JP 2008-289861 A

  However, the invention disclosed in Patent Document 1 does not give consideration to the following points.

  That is, when detecting the characteristic change of the coronary artery plaque lesion as described above, the patient (subject) is imaged using a contrast agent to obtain a necessary image, so that the degree of invasiveness to the subject is high. Therefore, it becomes a big burden for the subject.

  Of the risk factors described above, in particular, for calculating the P / M ratio, the signal value in the plaque region and the signal value in the muscle region necessary for the calculation have been manually acquired. Acquisition of these signal values is time-consuming, and much time is required for analysis of an image used to determine whether CAS can be applied.

  The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to automatically generate and display an image displaying the P / M ratio and the stenosis length, which are risk factors for embolic complications. By doing so, the amount of work of the doctor is reduced, the throughput is improved, and it is made easier to determine whether or not to apply CAS before surgery. In addition, image data acquisition necessary for generating a minimally invasive image of the subject is also performed. Another object of the present invention is to provide a medical image display device and a medical image display method capable of performing the above.

  According to a first aspect of the present invention, in the medical image display device, extraction is performed to extract a blood vessel region, a blood vessel lumen region, a plaque region, and a muscle region using image data acquired by photographing a subject. The processing means calculates the P / M ratio using the signal value in the plaque region and the signal value in the muscle region, and measures the stenosis length in the blood vessel using the blood vessel region, the blood vessel lumen region, and the plaque region. Image data analysis means comprising: measurement calculation processing means; judgment means for judging the presence or absence of risk factors based on information on the P / M ratio and stenosis length; and display means for displaying an analysis result by the image data analysis means Is provided.

  According to a third aspect of the present invention, in the medical image display method, a step of calculating a P / M ratio based on image data acquired by photographing a subject, and measuring a stenosis length in a blood vessel lumen A step of determining the presence / absence of a risk factor based on the P / M ratio and the stenosis length, and a step of displaying a determination result of the presence / absence of the risk factor.

  According to the present invention, by automatically generating and displaying an image displaying the P / M ratio and stenosis length, which are risk factors for embolic complications, the amount of work for the doctor is reduced and the throughput is improved. In addition, a medical image display device and a medical image display method capable of easily determining whether or not to apply CAS before surgery and also acquiring image data necessary for generating a less invasive image on a subject are also provided. can do.

It is a block diagram which shows the internal structure of the medical image display apparatus in embodiment of this invention. It is a block diagram which shows the internal structure of the image data analysis means in embodiment of this invention. It is a flowchart which shows the fundamental flow about the production | generation of the image used when the doctor in embodiment of this invention determines the applicability of CAS, and a display. It is the flowchart which showed the flow of P / M ratio calculation in embodiment of this invention. It is a schematic diagram showing the blood vessel region extracted in the flow of P / M ratio calculation. It is a schematic diagram which shows the anatomical position of a main tissue in the axial cross-sectional image shown by imaging | photography of a neck by MRI. It is a flowchart which shows the flow of the extraction process of the muscle area | region employ | adopted in the 1st Embodiment of this invention. It is a schematic diagram for demonstrating the method of the extraction process of a muscle area. It is a flowchart which shows the flow which measures the stenosis length in embodiment of this invention. It is a schematic diagram for demonstrating the method to measure stenosis length. It is a schematic diagram which shows an example of the image displayed on a display means. It is a flowchart which shows the flow which estimates the muscle area | region in the 2nd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(First embodiment)
FIG. 1 is a block diagram showing an internal configuration of a medical image display apparatus 1 according to an embodiment of the present invention. The medical image display apparatus 1 is an apparatus that generates and displays an optimal image for determining whether or not CAS can be applied to a doctor using image data acquired by imaging a subject. In this displayed image, it is possible to display “P / M ratio” and “stenosis length” which are risk factors highly related to embolic complications.

  Note that the image data of the subject used in the medical image display apparatus 1 is acquired by, for example, an X-ray diagnostic apparatus or a computed tomography (CT) apparatus in addition to the MRI described above.

  In the medical image display device 1, a CPU (Central Processing Unit) 1a, a ROM (Read Only Memory) 1b, a RAM (Random Access Memory) 1c, and an input / output interface 1d are connected via a bus 1e. An input unit 1f, a display unit 1g, a communication control unit 1h, a storage unit 1i, a removable disk 1j, and an image data analysis unit 10 are connected to the input / output interface 1d.

  The CPU 1a reads out and executes a boot program for starting up the medical image display apparatus 1 from the ROM 1b based on an input signal from the input unit 1f, and reads out various operating systems stored in the storage unit 1i. The CPU 1a controls various devices based on input signals from other external devices not shown in FIG. 1 via the input means 1f and the input / output interface 1d. Further, the CPU 1a reads out the program and data stored in the RAM 1c, the storage unit 1i, etc. and loads them into the RAM 1c. Based on the program command read out from the RAM 1c, the CPU 1a performs processing for image generation and data calculation. It is a processing device that realizes a series of processing such as processing.

  The input unit 1f is configured by an input device such as a keyboard and a dial for an operator (for example, a doctor or an examination engineer) of the medical image display apparatus 1 to input various operations, and an input signal based on the operation of the operator Is transmitted to the CPU 1a via the bus 1e. The medical image display device 1 is provided with a dedicated operation panel as well as a keyboard and the like, and an operation screen can be operated via an input device on the operation panel.

  The display means 1g is a liquid crystal display, for example. The display means 1g receives an output signal from the CPU 1a via the bus 1e and, for example, an image necessary for setting various conditions for image processing or displaying a generated image, a processing result of the CPU 1a, or the like. Is displayed.

  The communication control unit 1h is a unit such as a LAN card or a modem, and is a unit that enables the medical image display apparatus 1 to be connected to a communication network such as the Internet or a LAN. Data transmitted / received to / from the communication network via the communication control unit 1h is transmitted / received to / from the CPU 1a via the input / output interface 1d and the bus 1e as an input signal or an output signal.

  The storage means 1i is composed of a semiconductor or a magnetic disk, and stores programs and data executed by the CPU 1a. In addition, a blood vessel-muscle region position model or the like used for estimation of a muscle region described later is stored in advance.

  The removable disk 1j is an optical disk or a flexible disk, and signals read and written by the disk drive are transmitted to and received from the CPU 1a via the input / output interface 1d and the bus 1e.

  The image data analysis means 10 analyzes the image data taken of the subject, calculates and measures the P / M ratio and stenosis length, which are risk factors for embolic complications, and displays them together. Generate an image.

  In the embodiment of the present invention, the image data analysis means 10 performs a series of image processing, but the processing is not performed by the image data analysis means 10 but the image stored in the storage means 1i or the removable disk 1j. It can also be done by using a data analysis program. In this case, the image data analysis program stored therein is loaded into the medical image display apparatus 1 by being read and executed by the CPU 1a.

  FIG. 2 is a block diagram showing the internal configuration of the image data analysis means 10 in the embodiment of the present invention. The image data analysis unit 10 includes a reception unit 11, an extraction processing unit 12, a measurement calculation processing unit 13, a determination unit 14, and a transmission unit 15.

  The extraction processing unit 12 extracts, for example, a blood vessel region, which will be described later, based on the acquired image data of the subject. The measurement calculation processing means 13 measures or calculates the P / M ratio and the stenosis length using the extracted blood vessel region and the like. The determination unit 14 determines the presence / absence of a risk factor based on the measurement, the calculated P / M ratio, and the stenosis length, and presents it together with an image generated as a condition when the CAS can be applied.

  Next, the flow of image generation and display used when a doctor determines whether or not CAS can be applied will be described using the flowcharts shown in FIGS.

  FIG. 3 is a flowchart showing a basic flow of image generation and display used when a doctor determines whether or not CAS can be applied in the embodiment of the present invention. Items to be displayed as risk factors are “P / M ratio” and “stenosis length”. Therefore, how to measure, calculate and display these two factors is the subject of the flow described below.

  As described above, the “P / M ratio (Plaque / Muscle Ratio)” is the ratio between the signal value in the plaque region and the signal value of the adjacent muscle. It is determined that the higher the ratio, the higher the risk. On the other hand, the “stenosis length” is a length indicating a region showing a high stenosis rate along the longitudinal direction of the blood vessel due to plaque present in the blood vessel. This “stenosis length” is judged to be more dangerous because a larger value means that a region where stenosis occurs in the blood vessel is larger (longer).

  The image data analysis means 10 first acquires image data of the neck of the subject from an image photographing apparatus such as MRI (ST1). Although not shown in the figure, the image data analysis means 10 is connected to a modality such as MRI or, for example, a server that stores images via a network.

  In this case, the medical image display device 1 is, for example, a hospital information management system (HIS), a radiology information management system (RIS), a medical image management system (PACS: Picture Archiving Communication System). ) May be used in combination with various management systems built in medical institutions.

  Examples of this network include a network such as a LAN (Local Area Network) and the Internet. The communication standard used in this network may be any standard such as DICOM (Digital Imaging and Communication in Medicine).

  Image data acquired by the image data analysis means 10 from the image capturing device is a Black Blood method T1-weighted image and a three-dimensional image. These image data are accompanied by additional information such as an image type and an imaging position with respect to the subject.

  The image data analyzing unit 10 transmits the image data received by the receiving unit 11 to the extraction processing unit 12. The extraction processing unit 12 extracts a blood vessel region, a blood vessel lumen region, a plaque region, and a muscle region based on the acquired image data. Among these, in extracting a blood vessel region, a blood vessel lumen region, and a plaque region, each blood vessel region, blood vessel lumen region, and plaque region can be acquired by performing an existing extraction process. In addition, extraction is performed based on the analysis conditions memorize | stored in the memory | storage means 1i previously, for example.

  Next, the calculation process (ST2) of the P / M ratio will be described using the flowchart showing the flow of the P / M ratio calculation in FIG.

  In calculating the P / M ratio, two types of signal values, “signal value in the plaque region” and “signal value in the muscle region”, are required. Therefore, first, extraction processing means 12 performs plaque region extraction processing (ST21). In the Black Blood method T1-weighted image, the blood vessel is displayed to appear black, but the region where the plaque is present is displayed to appear white. The extraction processing means 12 extracts a plaque region for each image slice of the axial section from the image data.

  When the plaque region is extracted, the measurement calculation processing means 13 measures the signal value in the extracted plaque region, and further creates a histogram. The histogram shows the frequency for each gradation by dividing the measured signal value into appropriate gradations. Then, a central value is calculated from the histogram, and the value is set as a signal value in the plaque region (ST22).

  Here, the signal value in the plaque region is measured for each image slice, and signal values are measured for the number of image slices. Therefore, the measured signal value may include an extreme value. Therefore, in order to remove such values, a histogram is created to calculate an appropriate signal value. Thus, calculating the signal value leads to providing a more accurate image when displaying the image generated by the doctor.

  Next, the blood vessel region is extracted by the extraction processing means 12 (ST23). FIG. 5 is a schematic diagram showing the extracted blood vessel region. However, in this state, it is difficult to understand what kind of blood vessel is arranged at which position. Therefore, the extraction processing means 12 performs thinning processing and performs classification (ST24). By classifying the blood vessels, it becomes easy to estimate the position of the muscle region from the anatomical positional relationship. Therefore, extraction and classification of the blood vessel region are performed in order to calculate a signal value in the muscle region.

  As shown in FIG. 5, the thinning process classifies blood vessels into four blood vessels: “inner carotid artery O”, “external carotid artery P”, “common carotid artery Q”, and “vertebral artery R”. In the embodiment of the present invention, the sternocleidomastoid muscle M will be described as an example of the muscle region close to the carotid artery. Therefore, the signal value in the muscle region to be calculated is the signal value in the sternocleidomastoid muscle M.

  Furthermore, FIG. 6 is a schematic diagram showing anatomical positions of main tissues in an axial cross-sectional image obtained by imaging the neck by MRI. A spine A is shown near the center of the schematic diagram, and a spine B is shown at a position above the spine A. There is a vertebral artery R around the spine A, and the common carotid artery Q is located closer to the epidermis S than the vertebral artery R. The sternocleidomastoid muscle M is located further closer to the epidermis S of the common carotid artery Q. Therefore, the common carotid artery Q and the sternocleidomastoid muscle M are located in this order from the vertebral artery R toward the epidermis S. These positional relationships are almost anatomically determined.

  Next, a blood vessel lumen region is extracted (ST25). This vascular lumen region is used when measuring the stenosis length. Therefore, the step of measuring the stenosis length will be described.

  When the blood vessel region and the blood vessel lumen region are extracted, a muscle region extraction process is performed (ST26). As described above, from the anatomical positional relationship, the rough positions of the vertebral artery R, the common carotid artery Q, and the sternocleidomastoid muscle M can be grasped when represented as shown in FIG. However, since the schematic diagram shown in FIG. 6 is not actually created, the position of the sternocleidomastoid muscle M in the image data can be predicted, but it is not possible to calculate the signal value in the muscle region to be obtained only by this. Therefore, the signal value in the muscle region is calculated using the following procedure.

  FIG. 7 is a flowchart showing the flow of a muscle region extraction process employed in the first embodiment. FIG. 8 is a schematic diagram for explaining a method for extracting a muscle region. In FIG. 8, in the schematic diagram, the epidermis S is shown on the left side, and although not shown, the spine A exists on the right side. Therefore, from the anatomical position, it can be expected that the vertebral artery R, the common carotid artery Q, and the sternocleidomastoid muscle M exist from the right to the left in the schematic diagram.

  First, the vascular region RR of the vertebral artery R and the vascular region QR of the common carotid artery Q are specified for each acquired image slice from the vascular regions that have already undergone extraction processing (ST26A). Then, a half line H is drawn from the center of the vertebral artery blood vessel region RR toward the center of the common carotid artery blood vessel region QR (ST26B). That is, the direction of the half straight line H is the direction in which the sternocleidomastoid muscle M is located from the vertebral artery R.

  Here, it can be said that the vertebral artery blood vessel region RR is a blood vessel region serving as a basis for extracting a muscle region (thoracic chain mastoid muscle M). Further, it can be said that the common carotid artery blood vessel region QR is a proximal blood vessel region close to the muscle region (thoracic chain mastoid muscle M). Accordingly, if the desired muscle region is different, the basic blood vessel region and the adjacent blood vessel region are different.

  Next, since the common carotid artery blood vessel region QR has already been specified, the diameter X of the common carotid artery blood vessel region QR is obtained, and a half line H is extended by the same distance (distance X ′) as this diameter X ( ST26C).

  The reason why the common carotid artery blood vessel region QR is extended by the diameter X in this way is that the common carotid artery blood vessel region QR, which is the adjacent blood vessel region, is literally positioned close to the target muscle region (the sternocleidomastoid muscle M). is doing. Therefore, by extending the half straight line H by the distance X ', a portion located in the muscle region (chestoroid mastoid muscle M) appears on the half straight line H. Therefore, it can be estimated that at least a part of the half line H existing on the extended distance X ′ is in this muscle region (chesticular mastoid muscle M). In other words, by creating such a state, it is possible to estimate the muscle region (chest chain mastoid muscle M) (ST26D). Therefore, the extraction of the muscle region is completed.

  When the muscle region is extracted, the signal value in the extracted muscle region is calculated by the measurement calculation processing means 13 (flow chart of FIG. 4, ST27). When calculating the signal value in the muscle region, as in the case of calculating the signal value in the plaque region described above, a median is obtained after creating a histogram, and this median is used as the signal value in the muscle region. .

  Thus, the “signal value in the plaque region” and the “signal value in the muscle region” are calculated. Therefore, based on these two signal values, the measurement calculation processing means 13 calculates the P / M ratio for each image slice (ST28).

  Next, the “stenosis length” is measured (flow chart of FIG. 3, ST3). A specific measurement flow is shown in the flowchart shown in FIG. FIG. 10 is a schematic diagram for explaining a method of measuring the stenosis length.

  First, based on the blood vessel region extracted in step 23 (see the flowchart in FIG. 4), the extraction processing means 12 performs a thinning process for each blood vessel to obtain a blood vessel core (ST31). Then, the plaque region, the blood vessel region, and the blood vessel region in which the thinning process is performed and the blood vessel core line is obtained are overlapped (ST32). In FIG. 10, for convenience of explanation, the internal carotid artery O, the external carotid artery P, and the common carotid artery Q are shown, and furthermore, blood vessel core lines indicated by two-dot chain lines, one-dot chain lines, and broken lines are also shown. Further, in FIG. 10, plaque is observed in a region indicated by oblique lines from the internal carotid artery O to the common carotid artery Q.

  Next, a position away from the end of the plaque region by a predetermined distance is searched on the blood vessel core line (ST33). This will be described with reference to FIG. 10. This means that a position N ′ that is a predetermined distance L away from the N point (the end of the plaque region) is searched. The reason for searching for the position N ′ at a predetermined distance L from the end N of the plaque region is to measure the inner diameter α of the internal carotid artery O. This is because at this position N ′, the inner diameter α of the internal carotid artery O can be measured without being affected by plaque in the internal carotid artery O. Therefore, although the predetermined distance L can be arbitrarily set, it is preferable that the predetermined distance L is set to be a position sufficiently away from the end N of the plaque region.

  When the internal diameter α of the internal carotid artery O is measured by the measurement calculation processing means 13 (ST34), the internal diameter β at each position of the internal carotid artery O is then measured using the blood vessel lumen region (ST35). This measures the inner diameter β for each image slice along the blood vessel core line based on the blood vessel region that has already been extracted. For example, like the inner diameter β shown in FIG. 10, the inner diameter β at the position where the plaque region exists in the blood vessel is equal to the distance of the blood vessel lumen due to the presence of the plaque compared to the inner diameter α at the position where there is no plaque region. Becomes shorter.

  When both the inner diameter α and the inner diameter β are measured, the measurement calculation processing means 13 calculates the stenosis rate using the α value and the β value for each image slice (ST36). In calculating the stenosis rate, for example, a NASCET method that employs an equation of (1−β / α) × 100 can be used.

  When the stenosis rate is calculated for all image slices, a position exceeding a predetermined stenosis rate determined in advance is grasped on the blood vessel core line (ST37). As the stenosis rate approaches 100%, more plaque is accumulated in the blood vessel. The predetermined stenosis rate can be arbitrarily set, and is determined in advance and stored in the storage unit 1i.

  And the position which shows a high stenosis rate by the plaque which exists in the blood vessel is connected, and distance (length) is measured along the longitudinal direction of the blood vessel (ST38). This length is the stenosis length.

  According to the flow described above, the “P / M ratio” and the “stenosis length” are measured and calculated. Therefore, the measurement calculation processing unit 13 transmits the obtained value to the determination unit 14. The determination means 14 having received both values determines the presence or absence of risk factors from these values (ST4, see the flowchart of FIG. 3). The presence / absence of the risk factor is determined based on a threshold value stored in advance in the storage unit 1i. The determination unit 14 determines that a blood vessel region having a P / M ratio equal to or greater than a predetermined threshold and a stenosis length is a region having a risk factor.

  In addition, the determination unit 14 generates an image to be displayed on the display unit 1g, and displays the determination result and the like together (ST5). Examples of the generated image include an SVR (Shaded Volume Rendering) image and an MPR (Multiple Planer Reconstruction) image. An area that is determined to be an area having a risk factor is superimposed on these images, and quantitative numerical data is also displayed as character information.

  FIG. 11 is a schematic diagram illustrating an example of an image displayed on the display unit 1g. Here, conditions determined to be risk factors of P / M ratio distribution, P / M ratio, and stenosis length are shown. Further, particularly dangerous areas are highlighted by surrounding the areas.

  Note that information such as what kind of information is displayed on the display unit 1g, or a display layout of an image or character information, a generated image type such as an SVR image, an MPR image, or the like is input by a doctor or the like using the input unit 1f or the like. It is possible to set arbitrarily.

  As described above, as long as judgment conditions are set in advance, an image that displays P / M ratio and stenosis length, which are risk factors for embolic complications, is automatically generated and displayed. To reduce the workload of doctors and improve throughput, to easily determine whether or not to apply CAS before surgery, and also to acquire image data necessary for generating a minimally invasive image on a subject. It is possible to provide a medical image display device and a medical image display method.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. In the second embodiment, the same components as those described in the first embodiment are denoted by the same reference numerals, and the description of the same components is omitted because it is duplicated.

  The second embodiment is different from the first embodiment only in the method of extracting a muscle region when calculating the P / M ratio (see ST26 in the flowchart shown in FIG. 4). In the second embodiment, using the “blood vessel-muscle region position model”, the position of the muscle region is estimated more accurately from the anatomical positional relationship, and the signal value in the muscle region is calculated. For the purpose.

  Here, the “blood vessel-muscle region position model” is statistical information indicating the positional relationship between the blood vessel region and the muscle region. In this “blood vessel-muscle region position model”, the shape of a blood vessel core line and a branch point are shown as feature amounts. In addition, the relative distribution position of the muscle tissue based on these feature amounts is held for each type of muscle tissue. Since there are deformities in the running of the blood vessels, a blood vessel-muscle region position model is prepared for each of the deformity types with particular attention to branching. In the second embodiment, each of these models is stored in advance in the storage means 1i.

  FIG. 12 is a flowchart showing a flow of estimating a muscle region in the second embodiment. Here, first, thinning processing and classification processing are performed based on the extracted blood vessel region. This result is generated as an “analysis model” (ST26a). This “analysis model” can be said to be a model indicating the positional relationship between a blood vessel region and a muscle region peculiar to a subject generated for each subject with respect to the “blood vessel-muscle region position model”.

  Next, the generated analysis model and the blood vessel-muscle region position model are aligned with each other (ST26b). Then, a region that is considered to be a muscle region in the “blood vessel-muscle region position model” is estimated as a muscle region on the analysis model (ST26c).

  As described above, by estimating the muscle region using the “blood vessel-muscle region position model”, the muscle region can be estimated and the signal value can be calculated more quickly and accurately. In particular, by storing many types of “blood vessel-muscle region position model” in the storage unit 1 i in advance, it is possible to deal with more analysis models of subjects.

  By automatically generating and displaying images displaying the P / M ratio and stenosis length, which are risk factors for embolic complications, the amount of work for the doctor is reduced, throughput is improved, and preoperative It is possible to provide a medical image display apparatus and a medical image display method that make it easy to determine whether CAS can be applied, and that can acquire image data necessary for generating a minimally invasive image of a subject. .

  The present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. For example, for the calculation of the P / M ratio, the stenosis length, etc., each process is performed using a medical image display device, but each process may be performed with a modality such as MRI having the same apparatus configuration. .

  Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine the component covering different embodiment suitably.

DESCRIPTION OF SYMBOLS 1 Medical image display apparatus 10 Image data analysis means 11 Receiving means 12 Weekly processing means 13 Measurement calculation processing means 14 Judgment means 15 Transmission means

Claims (7)

An extraction processing means for extracting a blood vessel region, a blood vessel lumen region, a plaque region, and a muscle region using image data acquired by imaging a subject;
The P / M ratio is calculated using the signal value in the plaque region and the signal value in the muscle region, and the measurement calculation is used to measure the stenosis length in the blood vessel using the blood vessel region, the blood vessel lumen region, and the plaque region. Processing means;
A determination means for determining the presence / absence of a risk factor based on the information of the P / M ratio and the stenosis length;
Display means for displaying an analysis result by the image data analysis means;
A medical image display device comprising:   The medical image display device further includes a storage unit that stores a blood vessel-muscle region position model used for estimating the muscle region and a condition when the determination unit determines whether there is a risk factor. The medical image display device according to claim 1. Calculating a P / M ratio based on image data acquired by imaging a subject;
Measuring the stenosis length in the vessel lumen;
Determining the presence or absence of risk factors based on the P / M ratio and the stenosis length;
Displaying the determination result of the presence or absence of the risk factor;
A medical image display method comprising: The step of calculating the P / M ratio includes:
Extracting a plaque region in the blood vessel and calculating a signal value in the plaque region;
Extracting and classifying the blood vessel region;
Extracting a vessel lumen region;
Extracting a muscle region;
Calculating a signal value in the muscle region;
Calculating a P / M ratio based on the signal value in the plaque region and the signal value in the muscle region;
The medical image display method according to claim 3, further comprising: Extracting the muscle region comprises:
Identifying a blood vessel region as a basis for extracting the muscle region from the blood vessel region;
Identifying a nearby blood vessel region proximate to the muscle region from the blood vessel region;
Setting a half line connecting the center of the basic blood vessel region and the center of the adjacent blood vessel region;
Extending the half straight line by the same length as the blood vessel diameter of the adjacent blood vessel region; and
Estimating the region on the stretched half-line as a muscle region;
The medical image display method according to claim 4, further comprising: Extracting the muscle region comprises:
Performing thinning processing on the classified blood vessel region to generate an analysis model;
Aligning the analysis model with a blood vessel-muscle region position model that predetermines a positional relationship between blood vessels and muscle regions;
Estimating a region to be a muscle region in the blood vessel-muscle region position model as a muscle region in the analysis model;
The medical image display method according to claim 4, further comprising: The step of measuring the stenosis length comprises:
Performing thinning processing of the blood vessel region and obtaining a blood vessel core;
Overlapping the blood vessel region, the plaque region and the blood vessel core;
Searching for a position away from the end of the plaque region by a predetermined distance using the blood vessel core;
Measuring a first blood vessel diameter at a position searched on the blood vessel core line;
Measuring a second blood vessel diameter at each position along the blood vessel core line using the blood vessel lumen region;
Calculating a stenosis rate at each position of the vascular lumen region based on the first vascular diameter and the second vascular diameter;
Grasping on the blood vessel core line the position of the blood vessel lumen region having a stenosis rate exceeding a predetermined threshold; and
Measuring the length of the continuous position of the vascular lumen region having a stenosis rate exceeding the grasped predetermined threshold, and obtaining a stenosis length;
The medical image display method according to claim 3, further comprising: