JP7170850B2 - Pseudo-angio image generator, method and program - Google Patents

Description

The present disclosure relates to a pseudo-angio image generating device, method, and program for generating pseudo-angio images.

BACKGROUND ART Conventionally, contrast-enhanced radiographic image diagnostic apparatuses have been used to examine and treat the shape of blood vessels, abnormalities in blood vessels, the state of blood flow, and the like. A contrast-enhanced radiographic image diagnostic device is called an angiography device. In an angiography apparatus, a radiographic image of a blood vessel is acquired by injecting a contrast medium into a blood vessel using a catheter and imaging a patient with the contrast medium injected. By using an angiography device, examination and treatment can be performed while confirming blood flow distribution and vascular conditions, such as vascular stenosis, using angiographic images. Therefore, examination and treatment of blood vessels can be performed efficiently. .

On the other hand, with the progress of medical equipment such as CT (Computed Tomography) apparatus and MRI (Magnetic Resonance Imaging) apparatus, high-quality, high-resolution three-dimensional images have come to be used for image diagnosis. Therefore, when performing examination and treatment using the above-described angiography apparatus, three-dimensional images are acquired by a CT apparatus while blood vessels are contrasted with a contrast agent, and examination and treatment simulations are performed using the three-dimensional images. It is now being done. For example, by averaging each pixel of a three-dimensional image in one direction to generate a raysum image, which is a pseudo radiographic image projected, and performing processing to emphasize the contours of blood vessels in the raysum image, the angiography device can be used. It is becoming possible to simulate the tests and treatments used. However, each pixel value of the Latsum image is an arithmetic mean value of the pixel values of the plurality of pixels existing in the one direction in the three-dimensional image. For this reason, since the image of the blood vessel is included in the Latsum image in a blurred state, it is difficult to understand the state of the blood vessel.

For this reason, blood vessels are extracted from a three-dimensional image, a volume rendering image of the blood vessels is generated, and a pseudo-angio image is generated by superimposing the volume rendering image of the blood vessels on the position where the blood vessels exist in the Latham image. ing.

Also, a technique has been proposed in which a blood vessel region is extracted from an angio image, and the extracted blood vessel is aligned and displayed in a Latham image (see, for example, Patent Document 1). This makes it easier to recognize the position of the blood vessel in the body, so that examination and treatment using the angiography apparatus can be performed efficiently.

JP 2013-085652 A

However, since the volume rendering image is a three-dimensional image, even if the pseudo angio image is generated by superimposing the volume rendering image on the Latham image, which is a two-dimensional image, when the angio image is actually acquired, the blood vessel It is difficult to understand exactly how is included in the angio image. In addition, since the method described in Patent Document 1 requires capturing an angio image, the method described in Patent Document 1 cannot be used for examination and treatment simulation using an angiography apparatus.

The present disclosure has been made in view of the above circumstances, and aims to enable appropriate simulation of examination and treatment using an angiography apparatus.

A pseudo-angio-image generating apparatus according to the present disclosure includes a blood vessel region extraction unit that extracts a contrast-enhanced blood vessel region from a three-dimensional image of a subject that includes a contrast-enhanced blood vessel;
a Latsum image generation unit that generates a Latsum image of a subject based on the three-dimensional image;
a blood vessel-enhanced image generating unit that generates a blood vessel-enhanced image in which a contrasted blood vessel region is emphasized based on the three-dimensional image;
a synthesizing unit that superimposes the blood vessel-enhanced image on the contrast-enhanced blood vessel region in the Latham image to generate a pseudo-angio image.

In the pseudo-angio-image generating apparatus according to the present disclosure, the blood vessel-enhanced image generation unit may generate the blood vessel-enhanced image only for the partial blood vessel region that is part of the contrast-enhanced blood vessel region.

Further, in the pseudo-angio-image generating apparatus according to the present disclosure, the partial vascular region may be a predetermined vascular region extending from a specified position in the contrast-enhanced vascular region toward peripheral blood vessels.

Further, in the pseudo-angiographic image generating device according to the present disclosure, the blood vessel-enhanced image generation unit generates a plurality of blood vessel-enhanced images in which the partial blood vessel region is gradually enlarged from the designated position,
The synthesizing unit may generate a plurality of pseudo-angio images by superimposing each of the plurality of vessel-enhanced images on the contrast-enhanced vascular region in the Latham image.

Further, in the pseudo-angio-image generation device according to the present disclosure, the blood vessel-enhanced image generation unit may generate a maximum intensity projection image of the contrast-enhanced blood vessel region in the three-dimensional image as the blood vessel-enhanced image.

Further, in the pseudo-angio-image generating device according to the present disclosure, the blood vessel-enhanced image generating unit may generate a Latham image of only the contrast-enhanced blood vessel region in the three-dimensional image as the blood vessel-enhanced image.

Further, in the pseudo-angio-image generation device according to the present disclosure, the Latsum image generation unit may generate a Latsum image for a region other than the contrast-enhanced blood vessel region from the three-dimensional image.

A method for generating a pseudo-angio image according to the present disclosure extracts a contrast-enhanced vascular region from a three-dimensional image of a subject including a contrast-enhanced blood vessel,
generating a Latham image of the subject based on the three-dimensional image;
generating a blood vessel-enhanced image in which a contrasted blood vessel region is emphasized based on the three-dimensional image;
A pseudo-angio image is generated by superimposing a blood vessel-enhanced image on a contrast-enhanced blood vessel region in a Latham image.

Note that the pseudo-angio image generation method according to the present disclosure may be provided as a program for causing a computer to execute the method.

Another pseudo-angio image generator according to the present disclosure includes:
a memory for storing instructions for the computer to execute;
a processor configured to execute stored instructions, the processor comprising:
extracting a contrast-enhanced vascular region from a three-dimensional image of a subject including the contrast-enhanced blood vessel;
generating a Latham image of the subject based on the three-dimensional image;
generating a blood vessel-enhanced image in which a contrasted blood vessel region is emphasized based on the three-dimensional image;
A process of superimposing a blood vessel-enhanced image on a contrast-enhanced blood vessel region in a Latham image to generate a pseudo-angio image is executed.

According to the present disclosure, examination and treatment simulation using an angiography apparatus can be performed appropriately.

A diagram showing an outline of a diagnosis support system to which a pseudo-angio image generation device according to an embodiment of the present disclosure is applied A diagram showing a schematic configuration of an additional information display device realized by installing a pseudo-angio image generation program in a computer. A diagram for explaining the generation of a Latsum image A diagram for explaining the generation of a blood vessel-enhanced image. Diagram showing multiple blood vessel-enhanced images Diagram showing pseudo-angio image A diagram showing a screen that allows switching between pseudo-angio images Flowchart showing processing performed in the present embodiment

Embodiments of the present disclosure will be described below with reference to the drawings. FIG. 1 is a hardware configuration diagram showing an overview of a diagnosis support system to which a pseudo-angio image generation device according to an embodiment of the present disclosure is applied. As shown in FIG. 1, in this system, a pseudo-angio image generating device 1, a three-dimensional image capturing device 2, an image storage server 3, and an angio device 4 according to this embodiment are in a communicable state via a network 5. connected with

The three-dimensional image capturing device 2 is a device that generates a three-dimensional image representing a part of a subject to be diagnosed by photographing the part. Specifically, a CT device, an MRI device, and a PET ( Positron Emission Tomography) equipment, etc. The three-dimensional image generated by this three-dimensional image photographing device 2 is transmitted to the image storage server 3 and stored. In the present embodiment, the diagnosis target part of the subject is the aorta and arteries branching from the aorta, the three-dimensional imaging device 2 is a CT device, and the three-dimensional image is the aorta of the subject injected with a contrast medium. It is assumed to be a CT image of the chest and abdomen.

The image storage server 3 is a computer that stores and manages various data, and includes a large-capacity external storage device and database management software. The image storage server 3 communicates with other devices via a wired or wireless network 5 to transmit and receive image data and the like. Specifically, image data such as a three-dimensional image generated by the three-dimensional image capturing device 2 is obtained via a network, stored in a recording medium such as a large-capacity external storage device, and managed. The image data storage format and communication between devices via the network 5 are based on a protocol such as DICOM (Digital Imaging and Communication in Medicine). Also, a tag based on the DICOM standard is attached to the three-dimensional image. The tag includes information such as a patient name, information representing an imaging device, imaging date and time, and an imaging region.

The angiography device 4 is a device for examining and treating the shape of a subject's blood vessels, blood vessel abnormalities, blood flow conditions, and the like. The angio device 4 includes a display unit 4A of the angio device 4 such as a liquid crystal display, and an angio image of the subject photographed by the angio device 4 is displayed. The doctor examines and treats the blood vessel while viewing the angio image displayed on the display unit 4A of the angio apparatus 4. FIG. In this embodiment, the angiography apparatus 4 examines and treats the aorta and arteries branching from the aorta.

The pseudo-angio image generating apparatus 1 is one computer in which the pseudo-angio image generating program of the present embodiment is installed. The computer may be a workstation or personal computer directly operated by a doctor who diagnoses, or a server computer connected to them via a network. The pseudo-angio-image generating program is stored in a storage device of a server computer connected to a network or network storage in an externally accessible state, and is downloaded and installed on a computer used by a doctor upon request. Alternatively, it is recorded on a recording medium such as a DVD (Digital Versatile Disc) or a CD-ROM (Compact Disc Read Only Memory), distributed, and installed in a computer from the recording medium.

FIG. 2 is a diagram showing a schematic configuration of a pseudo-angio image generating device realized by installing a pseudo-angio image generating program in a computer. As shown in FIG. 2, the pseudo-angio image generating apparatus 1 has a CPU 11, a memory 12 and a storage 13 as a standard workstation configuration. A display unit 14 such as a liquid crystal display and an input unit 15 such as a mouse are connected to the pseudo-angio image generating apparatus 1 . A touch panel that serves as both the display unit 14 and the input unit 15 may be used.

The storage 13 stores various kinds of information including the three-dimensional images acquired from the image storage server 3 via the network 5 and the pseudo-angio images generated by the processing in the pseudo-angio image generating device 1 .

The memory 12 also stores a pseudo-angio image generation program. The pseudo-angio-image generation program is executed by the CPU 11 as processing to acquire a three-dimensional image of the subject, including the aorta and arteries branching from the aorta contrasted with a contrast agent, and a contrast-enhanced blood vessel, which will be described later, from the three-dimensional image. A blood vessel region extraction process for extracting a region, a Latsum image generation process for generating a Latsum image of a subject based on a three-dimensional image, and a blood vessel enhancement process for generating a blood vessel-enhanced image in which the contrast-enhanced blood vessel region is emphasized based on the three-dimensional image. An image generation process, a synthesizing process of superimposing a vessel-enhanced image on a contrast-enhanced vascular region in a Latsum image to generate a pseudo-angio image, and a display control process of displaying the pseudo-angio image on the display unit 14 are defined.

Then, by the CPU 11 executing these processes according to the program, the computer becomes an image acquiring unit 21, a blood vessel region extracting unit 22, a Latsum image generating unit 23, a blood vessel emphasized image generating unit 24, a synthesizing unit 25, and a display control unit 26. function as

The image acquisition unit 21 acquires a three-dimensional image V0 to be processed including the contrast-enhanced aorta and arteries branching from the aorta from the image storage server 3 via an interface (not shown) connected to a network. The image acquisition unit 21 may acquire the three-dimensional image V0 from the storage 13 when the three-dimensional image V0 is already stored in the storage 13 .

The blood vessel region extraction unit 22 extracts a blood vessel region that has been contrasted (hereinafter referred to as a contrasted blood vessel region) from the three-dimensional image V0. In this embodiment, the vascular region to be imaged is a vascular region including the aorta and arteries branching from the aorta. The blood vessel region extraction unit 22 extracts a contrast-enhanced blood vessel region from the three-dimensional image V0, for example, by the method described in Japanese Patent Application Laid-Open Nos. 2010-200925 and 2010-220742. In this method, first, the positions and principal axis directions of a plurality of candidate points forming the center line of the blood vessel are calculated based on the values of the voxel data forming the three-dimensional image V0. Alternatively, the Hessian matrix is calculated for the three-dimensional image V0, and the eigenvalues of the calculated Hessian matrix are analyzed to calculate position information and principal axis directions of a plurality of candidate points forming the center line of the blood vessel. Then, a feature amount representing blood vessel-likeness is calculated for voxel data around the candidate point, and whether or not the voxel data represents a blood vessel is determined based on the calculated feature amount. Determination based on the feature amount is performed based on an evaluation function obtained in advance by machine learning. As a result, the contrast-enhanced vascular region and its core line are extracted from the three-dimensional image V0. Alternatively, the core line may be extracted by first extracting the contrast-enhanced vascular region and performing the thinning process on the extracted contrast-enhanced vascular region.

The Latsum image generation unit 23 perspectively projects the three-dimensional image V0 and performs Latsum rendering processing to generate a Latsum image, which is a pseudo radiographic image of the subject. FIG. 3 is a diagram for explaining generation of a Latsum image. Note that generation of a Latsum image for a partial three-dimensional image representing a partial area of the three-dimensional image will be described here. As shown in FIG. 3, the raysum image generator 23 perspectively projects a partial three-dimensional image V1 representing a partial area of the three-dimensional image V0 in the y direction shown in FIG. A Latsum image R0 is generated by performing Latsum rendering for calculating an arithmetic mean of values. In this embodiment, the x direction in FIG. 3 corresponds to the left-right direction of the subject, the y direction corresponds to the front-rear direction of the subject, and the z direction corresponds to the body axis direction of the subject. Therefore, the Latsum image R0 simulates a radiation image generated by photographing the subject from the front. Here, in the present embodiment, in the raysum rendering, CT value conversion is performed such that the larger the CT value, the higher the density (that is, the darker). That is, the CT value may be converted so that the image becomes whiter.

In the three-dimensional image V0, blood vessels are contrast-enhanced, so the contrast-enhanced blood vessel region has a different CT value from regions other than blood vessels. However, since the CT values of all pixels arranged in the y direction are averaged by Raysum rendering, the contrast-enhanced blood vessel region is inconspicuous in the Raysum image R0 due to the influence of the CT values of pixels in regions other than the contrast-enhanced blood vessel region. It has become a thing.

The blood vessel-enhanced image generation unit 24 generates a blood vessel-enhanced image in which the contrast-enhanced blood vessel region extracted from the three-dimensional image V0 by the blood vessel region extraction unit 22 is emphasized. FIG. 4 is a diagram for explaining the generation of a blood vessel-enhanced image. In this embodiment, the blood vessel-enhanced image generator 24 performs maximum intensity projection in the y direction shown in FIG. Then, a maximum intensity projection image (MIP (Maximum Intensity Projection) image) of the contrast-enhanced vascular region 30 is generated as a vessel-enhanced image T0. Note that in FIG. 4, the blood vessel-enhanced image T0 is generated for a partial blood vessel region, which is not all the blood vessels included in the partial three-dimensional image V1, but some blood vessels. Here, the partial vascular region is a vascular region of a predetermined range extending from a specified position in the contrast-enhanced vascular region 30 included in the partial three-dimensional image V1 toward peripheral blood vessels. Note that instead of the maximum intensity projection image, a raysum image of only the contrast-enhanced blood vessel region 30 may be used as the blood vessel-enhanced image T0. Further, the blood vessel-enhanced image T0 may be filtered to enhance edges.

The position can be specified by displaying the three-dimensional image V0 on the display unit 14 by a technique such as volume rendering, for example, and instructing the displayed three-dimensional image V0 using the input unit 15 by the operator. Just do it.

Further, in the present embodiment, the blood vessel-enhanced image generation unit 24 is assumed to generate a plurality of blood vessel-enhanced images in which the partial blood vessel regions are gradually enlarged from the specified position. FIG. 5 is a diagram showing a plurality of blood vessel-enhanced images. As shown in FIG. 5, in the four vessel-enhanced images T1 to T4, the partial vessel region increases stepwise from the designated position P0 to a predetermined range. Note that the blood vessel-enhanced image T4 is the same as the blood vessel-enhanced image T0 shown in FIG.

The synthesizing unit 25 superimposes the blood vessel-enhanced image on the contrast-enhanced blood vessel region in the Raysum image R0 to generate a pseudo-angio image. In this embodiment, four blood vessel-enhanced images T1 to T4 are generated as shown in FIG. Therefore, the synthesizing unit 25 superimposes each of the vessel-enhanced images T1 to T4 on the raysum image R0 to generate four pseudo-angio images G1 to G4. At this time, the synthesizing unit 25 superimposes the contrast-enhanced vascular region in the raysum image R0 and the vascular-enhanced images T1 to T4 by changing the transparency of each. Specifically, the transparency of the contrast-enhanced blood vessel region in the Raysum image R0 is increased, the transparency of the vessel-enhanced images T1 to T4 is decreased, and the vessel-enhanced images T1 to T4 are superimposed on the Raysum image R0. Note that the transparency of the contrast-enhanced blood vessel region in the raysum image R0 may be set to 1, and the transparency of the blood vessel enhanced images T1 to T4 may be set to 0.

FIG. 6 is a diagram showing a pseudo-angio image. In the pseudo-angio images G1 to G4, the contrast-enhanced vascular region, which was inconspicuous in the Latsum image R0, is emphasized. In the pseudo-angio images G1 to G4, the contrast-enhanced blood vessel area is gradually enlarged. Therefore, when a blood vessel is examined and treated using the actual angiography apparatus 4, the spread of the contrast medium is simulated when the contrast medium is injected from the position P0.

Note that when the blood vessel-enhanced image generating unit 24 generates only one blood vessel-weighted image T0, the synthesizing unit 25 superimposes the blood vessel-weighted image T0 on the position of the blood vessel in the raysum image R0 to form one pseudo-angiographic image. Only G0 needs to be generated.

The display control unit 26 displays the pseudo-angio images G1 to G4 on the display unit 14. FIG. Note that in this embodiment, a plurality of pseudo-angio images G1 to G4 are generated. Therefore, the display control unit 26 sequentially switches and displays the pseudo-angio images G1 to G4 according to an instruction from the input unit 15 by the operator. If the input unit 15 has a mouse, the instruction to switch the display may be performed using the scroll wheel of the mouse. Further, as shown in FIG. 7, a slider 40 may be displayed on the display unit 14, and pseudo-angio images G1 to G4 may be switched and displayed by changing the position of the knob 41 on the slider 40. FIG. This makes it easy to simulate how the contrast medium spreads when the contrast medium is injected from the position P0. It should be noted that a plurality of pseudo-angio images G1 to G4 may be switched and displayed like a moving image without giving an instruction from the input unit 15. FIG.

Next, processing performed in this embodiment will be described. FIG. 8 is a flow chart showing the processing performed in this embodiment. First, the image acquisition unit 21 acquires a three-dimensional image V0 (step ST1), and the blood vessel region extraction unit 22 extracts a contrast-enhanced blood vessel region from the three-dimensional image V0 (step ST2). Next, the Latsum image generation unit 23 generates a Latsum image R0 from the three-dimensional image V0 (step ST3), and the vessel-enhanced image generation unit 24 creates vessel-enhanced images T1 to T4 in which the contrast-enhanced vascular region is emphasized ( step ST4). Further, the synthesizing unit 25 superimposes the vessel-enhanced images T1-T4 on the contrast-enhanced vascular region in the Raysum image R0 to generate pseudo-angio images G1-G4 (step ST5). Then, the display control unit 26 displays the pseudo-angio images G1 to G4 on the display unit 14 (step ST6), and the process is terminated.

As described above, in the present embodiment, the vessel-enhanced images T1 to T4 in which the contrasted vessels are emphasized are superimposed on the contrasted vessel region in the raysum image R0 to generate the pseudo angio images G1 to G4. did. The blood vessel-enhanced images T1 to T4 are two-dimensional images, not three-dimensional images representing depth such as volume rendering images. Therefore, in the pseudo-angio images G1 to G4, the contrast-enhanced blood vessels are superimposed without discomfort. Therefore, according to this embodiment, examination and treatment simulation using the angiography apparatus 4 can be performed appropriately.

Although the blood vessel-enhanced images T1 to T4 of the partial blood vessel region are generated in the above embodiment, the present invention is not limited to this. A blood vessel-enhanced image of all contrast-enhanced blood vessel regions included in the three-dimensional image V0 may be generated.

Further, in the above embodiment, the transparency of the blood vessel-enhanced images T1-T4 may be changed when the pseudo-angio images G1-G4 are displayed. In this case, a slider for changing the transparency may be displayed on the display screen displaying the pseudo-angio images G1 to G4, and the transparency may be changed by changing the position of the knob of the slider.

Also, in the above embodiment, four blood vessel-enhanced images T1 to T4 are generated, but the number of blood vessel-enhanced images to be generated is not limited to four. A plurality of blood vessel-enhanced images of 3 or less or 5 or more may be generated. In this case, the number of pseudo-angio images is generated according to the number of blood vessel-enhanced images.

In the above embodiment, the Latsum image R0 is generated using the three-dimensional image V0. may be generated.

Further, in the above embodiment, the blood vessel region extraction unit 22 extracts the core line of the blood vessel, but only the core line of the blood vessel may be extracted by the operator's instruction from the input unit 15 . In this case, the blood vessel region extracting unit 22 extracts the contrast-enhanced blood vessel region from the three-dimensional image V0 based on the center line designated by the operator. The core line can be specified by, for example, displaying the three-dimensional image V0 on the display unit 14 by a method such as volume rendering, and giving an operator's instruction to the displayed three-dimensional image V0 using the input unit 15. .

In addition, in the above embodiment, the aorta and arteries branching from the aorta are used as diagnosis target sites, but the present invention is not limited to this. For example, the present embodiment can also be applied when a coronary artery, cerebral artery, or the like is to be diagnosed.

Further, in the above embodiment, a CT image is used as the three-dimensional image V0, but the present invention is not limited to this, and an MRI image, a PET image, or the like may be used.

Further, in the above embodiment, for example, the image acquiring unit 21, the blood vessel region extracting unit 22, the Latsum image generating unit 23, the blood vessel emphasized image generating unit 24, the synthesizing unit 25, and the display control unit 26 are processing units that execute various processes. As the hardware structure of (Processing Unit), various processors shown below can be used. In addition to the CPU, which is a general-purpose processor that executes software (programs) and functions as various processing units, as described above, the various processors described above include circuits such as FPGAs (Field Programmable Gate Arrays) after manufacturing. Programmable Logic Device (PLD), which is a processor whose configuration can be changed, ASIC (Application Specific Integrated Circuit), etc. Circuits, etc. are included.

One processing unit may be configured with one of these various processors, or a combination of two or more processors of the same or different type (for example, a combination of multiple FPGAs or a combination of a CPU and an FPGA). ). Also, a plurality of processing units may be configured by one processor.

As an example of configuring a plurality of processing units in one processor, first, as represented by computers such as clients and servers, one processor is configured by combining one or more CPUs and software, There is a form in which this processor functions as a plurality of processing units. Secondly, as typified by System On Chip (SoC), etc., there is a form of using a processor that realizes the functions of the entire system including multiple processing units with a single IC (Integrated Circuit) chip. be. In this way, the various processing units are configured using one or more of the above various processors as a hardware structure.

Furthermore, more specifically, as the hardware structure of these various processors, an electric circuit (circuitry) in which circuit elements such as semiconductor elements are combined can be used.

1 pseudo-angio image generating device 2 three-dimensional image capturing device 3 image storage server 4 angio device 4A display unit of angio device 4 5 network 11 CPU
12 memory 13 storage 14 display unit 15 input unit 21 image acquisition unit 22 blood vessel region extraction unit 23 raysum image generation unit 24 blood vessel enhanced image generation unit 25 synthesis unit 26 display control unit 30 contrast-enhanced blood vessel region 40 slider 41 knob G1 to G4 pseudo-angio Image P0 Position R0 Latham image T0 to T4 Vessel-enhanced image V0 Three-dimensional image V1 Partial three-dimensional image

Claims (7)

a blood vessel region extracting unit for extracting a contrast-enhanced blood vessel region from a three-dimensional image of a subject including the contrast-enhanced blood vessel;
a Latsum image generation unit that generates a Latsum image of the subject based on the three-dimensional image;
Blood vessel-enhanced image generation for generating a maximum intensity projection image of the contrast-enhanced blood vessel region in the three-dimensional image or a Lasum image of only the contrast-enhanced blood vessel region in the three-dimensional image as a blood vessel-enhanced image in which the contrast-enhanced blood vessel region is emphasized. Department and
and a synthesizing unit that superimposes the vessel-enhanced image on the contrast-enhanced vascular region in the Latham image to generate a pseudo-angio image. 2. The pseudo-angio-image generating apparatus according to claim 1, wherein the blood vessel-enhanced image generator generates the blood vessel-enhanced image only for a partial blood vessel region that is a part of the contrast-enhanced blood vessel region. 3. The pseudo-angio-image generating apparatus according to claim 2, wherein said partial vascular region is a vascular region of a predetermined range extending from a specified position in said contrast-enhanced vascular region to a peripheral blood vessel. The blood vessel-enhanced image generation unit generates a plurality of blood vessel-enhanced images in which the partial blood vessel region is enlarged stepwise from the specified position,
4. The pseudo-angio image generating apparatus according to claim 3, wherein the synthesizing unit generates a plurality of the pseudo-angio images by superimposing each of the plurality of vessel-enhanced images on the contrast-enhanced vascular region in the Laysum image. 5. The pseudo-angio-image generating apparatus according to any one of claims 1 to 4 , wherein the raysum image generator generates a raysum image of a region other than the contrast-enhanced blood vessel region from the three-dimensional image. extracting a contrast-enhanced vascular region from a three-dimensional image of a subject including the contrast-enhanced blood vessel;
generating a Latham image of the subject based on the three-dimensional image;
generating a maximum intensity projection image of the contrast-enhanced vascular region in the three-dimensional image or a raysum image of only the contrast-enhanced vascular region in the three-dimensional image as a vessel-enhanced image in which the contrast-enhanced vascular region is emphasized;
A pseudo-angio image generating method for generating a pseudo-angio image by superimposing the vessel-enhanced image on the contrast-enhanced vascular region in the Latham image. a procedure for extracting a contrast-enhanced vascular region from a three-dimensional image of a subject including the contrast-enhanced blood vessel;
generating a Latsum image of the subject based on the three-dimensional image;
a procedure of generating a maximum intensity projection image of the contrast-enhanced vascular region in the three-dimensional image or a Lasum image of only the contrast-enhanced vascular region in the three-dimensional image as a vessel-enhanced image in which the contrast-enhanced vascular region is emphasized;
A pseudo-angio image generating program for causing a computer to execute a procedure of superimposing the vessel-enhanced image on the contrast-enhanced vascular region in the Latham image to generate a pseudo-angio image.

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