WO2019003749A1 - 医用画像処理装置、方法およびプログラム - Google Patents
医用画像処理装置、方法およびプログラム Download PDFInfo
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Definitions
- the present invention relates to a medical image processing apparatus, method, and program for determining the amount of change in brain using brain images including brains of the same subject having different imaging dates and times.
- Alzheimer's disease With the advent of the aging society, patients with dementia disease are increasing year by year. Dementia develops when brain atrophy progresses by accumulation of a protein called amyloid ⁇ in the brain and cognitive ability declines. There is no cure for dementia, so early detection of brain atrophy and early treatment to slow the progression of dementia are important for maintaining quality of life.
- SPECT Single Photon Emission Computed Tomography
- PET PET
- CT images and MRI Magnetic Resonance Imaging
- Information on the state of the brain has become available by means of MRI images acquired by the device. For example, reductions in blood flow and metabolism in localized areas of the brain can be found by using SPECT and PET images to determine changes over time in localized areas of the brain.
- brain atrophy can be found by determining the volume of a specific region of the brain by MRI images and comparing temporal changes in volume. For example, according to Patent Document 1, alignment of two brain images different in shooting date and time is performed, and then each of the two brain images is divided into tissue areas (gray matter and white matter), and the amount of change is determined for each tissue area. A method for acquiring has been proposed.
- Non-Patent Documents 1 and 2 there has been proposed a method of subjecting a patient's brain image to segmentation by aligning a standard brain image segmented according to Brodmann's brain map with the patient's brain image.
- the brain map of Brodmann it is indicated which area is responsible for which brain function (movement, language, perception, memory, vision, hearing, etc.) in the three-dimensional area of the cerebral cortex of the standard brain. It is done.
- a method of dividing the brain image of a patient into regions and acquiring the amount of change in volume for each region Non-Patent Documents 1 and 2).
- Non-Patent Documents 1 and 2 first, the first brain image of the patient and the standard brain image are aligned, the first brain image is segmented, and the first brain image is compared with the first brain image.
- the second brain image of the patient whose imaging date and time is new is aligned with the standard brain image of the patient to segment the second brain image. Then, the amount of change in volume between corresponding regions in the first brain image and the second brain image is acquired.
- the shape and size of the brain vary greatly depending on the person. For example, it is known that the shape and size of an individual's brain will differ by up to ⁇ 15% as compared to a standard brain. For this reason, in order to align a patient's brain image and a standard brain image, it may be necessary to greatly deform a patient's brain image. On the other hand, the degree of brain atrophy due to dementia, that is, the change in brain volume is several percent per year. In the non-patent documents 1 and 2 described above, the first and second brain images of the patient to be compared are respectively aligned with the standard brain image.
- the present invention has been made in view of the above circumstances, and it is an object of the present invention to accurately obtain the amount of change between two brain images different in imaging date and time of the same patient.
- a medical image processing apparatus aligns a plurality of brains included in a first brain image by aligning a first brain image including the brain of a subject with a standard brain image divided into a plurality of regions.
- a division unit that divides into areas of An alignment unit for aligning a second brain image including the brain of the subject and having a different imaging date and time from the first brain image, and the first brain image;
- the first brain image of at least one of a plurality of regions in the brain included in the second brain image
- a change amount acquisition unit for acquiring a change amount from a corresponding region in the brain included.
- the change amount acquisition unit calculates a volume change amount for at least one of a plurality of regions in the brain included in the second brain image. It is also good.
- the medical image processing apparatus may further include a display control unit for displaying the volume change amount on the display unit.
- the alignment unit is a movement vector of the corresponding pixel position between corresponding areas of the brain included in the first brain image and the second brain image. May be acquired as the amount of change.
- the dividing unit performs the first alignment using the landmarks between the first brain image and the standard brain image, and then performs the first brain image and the standard.
- a second alignment between brain images may be performed.
- the first alignment may be alignment by similarity conversion
- the second alignment may be alignment by non-linear conversion
- the first registration is registration using landmarks
- the second registration is registration using an arbitrary region between the standard brain image and the first brain image.
- the alignment using an arbitrary area may be, for example, an alignment using the entire area between the standard brain image and the first brain image, or even if only an area is used. Good.
- a “landmark” is an area having a characteristic shape in a brain image, and specifically, at least one of the characteristic areas such as the cerebral sulcus and the ventricles contained in the brain may be used as a landmark. it can.
- the alignment unit performs the third alignment after using the landmarks between the first brain image and the second brain image.
- a fourth alignment may be performed between the image and the second brain image.
- the third alignment may be rigid alignment
- the fourth alignment may be alignment by non-linear transformation
- the third alignment is alignment using landmarks
- the fourth alignment is alignment using an arbitrary area between the first brain image and the second brain image.
- the alignment using an arbitrary area may be, for example, the alignment using the entire area between the first brain image and the second brain image, or only the partial area. May be
- a plurality of brains included in the first brain image can be obtained by aligning the first brain image including the brain of the subject with the standard brain image divided into a plurality of regions. Divided into areas of Align a second brain image including the subject's brain and the first brain image, the first brain image and the imaging date and time being different; According to the alignment result of the first brain image and the second brain image, the first brain image of at least one of a plurality of regions in the brain included in the second brain image Acquire the amount of change from the corresponding area in the included brain.
- the medical image processing method according to the present invention may be provided as a program for causing a computer to execute the method.
- Another medical image processing apparatus is a memory for storing instructions to be executed by a computer.
- a processor configured to execute the stored instructions, the processor
- the brain included in the first brain image is divided into a plurality of regions by aligning the first brain image including the brain of the subject and the standard brain image divided into the plurality of regions, Align a second brain image including the subject's brain and the first brain image, the first brain image and the imaging date and time being different; According to the alignment result of the first brain image and the second brain image, the first brain image of at least one of a plurality of regions in the brain included in the second brain image The process of acquiring the amount of change from the corresponding region in the included brain is executed.
- the plurality of regions of the brain included in the first brain image can be obtained.
- the second brain image including the subject's brain and the first brain image having different imaging dates and times from the first brain image are aligned with each other, and the first brain image and the second brain image are An amount of change from a corresponding region in the brain included in the first brain image is acquired for at least one of the plurality of regions in the brain included in the second brain image based on the alignment result.
- the second brain image is aligned with the first brain image, but since the first and second brain images are images of the same subject, the second brain image is deformed so much. Even if it does not, it can align with a 1st brain image precisely. For this reason, compared to the case where both the first brain image and the second brain image are aligned with the standard brain image, each region of the brain included in the first brain image and the second brain image It is possible to accurately obtain a slight amount of change between each included brain region.
- a hardware configuration diagram showing an outline of a diagnosis support system to which a medical image processing apparatus according to an embodiment of the present invention is applied A diagram showing a schematic configuration of a medical image processing apparatus Figure showing a standard brain image Diagram showing the first brain image
- FIG. 1 is a hardware configuration diagram showing an outline of a diagnosis support system to which a medical image processing apparatus according to an embodiment of the present invention is applied.
- the medical image processing apparatus 1, the three-dimensional image capturing apparatus 2 and the image storage server 3 according to the present embodiment are connected in a communicable state via the network 4 There is.
- the three-dimensional image capturing device 2 is a device that generates a three-dimensional image representing a region to be diagnosed as a medical image by capturing a region to be diagnosed of a patient who is a subject.
- a CT device It is an MRI apparatus, a PET apparatus, and the like.
- the medical image generated by the three-dimensional image capturing device 2 is transmitted to the image storage server 3 and stored.
- the diagnosis target site of the patient who is the subject is the brain
- the three-dimensional image capturing device 2 is the MRI device
- the MRI image of the head including the brain of the subject is three-dimensional Generate as an image.
- the image storage server 3 is a computer that stores and manages various data, and includes a large-capacity external storage device and software for database management.
- the image storage server 3 communicates with other devices via a wired or wireless network 4 to transmit and receive image data and the like.
- various data including image data of a medical image generated by the three-dimensional image capturing device 2 is acquired via a network, and stored and managed in a recording medium such as a large-capacity external storage device.
- the storage format of image data and communication between devices via the network 4 are based on a protocol such as DICOM (Digital Imaging and Communication in Medicine).
- DICOM Digital Imaging and Communication in Medicine
- the medical image processing apparatus 1 is obtained by installing the medical image processing program of the present invention in one computer.
- the computer may be a workstation or a personal computer directly operated by a doctor performing diagnosis, or a server computer connected with them via a network.
- the medical image processing program is distributed by being recorded in a recording medium such as a digital versatile disc (DVD) or a compact disc read only memory (CD-ROM), and installed in a computer from the recording medium.
- DVD digital versatile disc
- CD-ROM compact disc read only memory
- it is stored in a storage device of a server computer connected to a network or in a network storage in an accessible state from the outside, downloaded to a computer used by a doctor in response to a request, and installed.
- FIG. 2 is a view showing a schematic configuration of a medical image processing apparatus realized by installing a medical image processing program in a computer.
- the medical image processing apparatus 1 has a central processing unit (CPU) as a standard work station configuration. 11, a memory 12 and a storage 13 are provided. Further, the display 14 and an input unit 15 such as a keyboard and a mouse are connected to the medical image processing apparatus 1.
- the display 14 corresponds to the display unit.
- the storage 13 stores various information including a brain image of a subject acquired from the image storage server 3 via the network 4, a standard brain image to be described later, and information necessary for processing.
- the memory 12 stores a medical image processing program.
- the medical image processing program includes, as processing to be executed by the CPU 11, an image acquisition process for acquiring first and second brain images having different imaging dates and times including the brain of the same subject, and the first process including the brain of the subject.
- Change amount acquisition processing for acquiring the amount of change from the corresponding region in the brain included in the first brain image for at least one region of the plurality of regions in the brain included in the brain image of Display on display 14 To define the that display control processing.
- the medical image processing apparatus 1 may include a plurality of processors or processing circuits that respectively perform image acquisition processing, division processing, alignment processing, change amount acquisition processing, and display control processing.
- the image acquisition unit 21 acquires, from the image storage server 3, two brain images different in imaging date and time, that is, the first brain image B1 and the second brain image B2 including the brains of the same subject.
- the image acquiring unit 21 acquires the first and second brain images B1 and B2 from the storage 13.
- the first brain image B1 has an imaging date and time older than that of the second brain image B2.
- what is stored in the image storage server 3 is a brain image acquired by imaging the head of the subject, and also includes a structure other than the brain such as a skull.
- the image acquisition unit 21 also acquires a standard brain image Bs from the image storage server 3.
- the dividing unit 22 divides the brain included in the first brain image B1 into a plurality of regions by aligning the first brain image B1 with the standard brain image Bs divided into the plurality of regions.
- the standard brain image Bs is a three-dimensional brain image representing a brain having a standard shape and size and a standard density (pixel value), that is, a standard brain.
- the standard brain image Bs can be generated by extracting the brains from a plurality of brain images obtained by acquiring the heads of a plurality of healthy persons using a three-dimensional image capturing device and averaging the plurality of extracted brains.
- the standard brain image Bs may be created by computer graphics or the like. Alternatively, the brain image of one healthy person may be used as a standard brain image Bs.
- the standard brain image Bs is divided into a plurality of regions.
- the cerebral cortex is divided into areas responsible for functions such as motion, speech, perception, memory, vision and hearing in a three-dimensional area of the cerebral cortex.
- An approach can be used.
- any known method such as a method of dividing into 6 types of regions of cerebrum, interbrain, midbrain, hindbrain, cerebellum and medulla oblongata, or a method of classifying cerebrum into frontal lobe, parietal lobe, temporal lobe and occipital lobe, etc. An approach can be used.
- FIG. 3 is a view showing an example of a standard brain image.
- the standard brain image Bs is divided into a plurality of regions in accordance with Brodmann's brain map.
- FIG. 4 is a diagram showing a first brain image B1.
- the first brain image B1 is different in shape and size from the standard brain image Bs shown in FIG.
- the dividing unit 22 performs a first alignment using a landmark between the first brain image B1 and the standard brain image Bs. Then, after performing the first alignment, the second alignment using the entire region between the first brain image B1 and the standard brain image Bs is performed.
- the landmark specifically, at least one of characteristic regions such as the cerebral sulcus and the ventricles included in the brain can be used.
- the standard brain image Bs is described as being aligned with the first brain image B1, but the first brain image B1 may be aligned with the standard brain image Bs.
- the dividing unit 22 extracts landmarks from the first brain image B1 and the standard brain image Bs.
- the extraction of the landmark may be performed by template matching using, for example, a template representing the landmark, or may be performed by using a discriminator trained so as to discriminate the landmark included in the image.
- the dividing unit 22 performs the first alignment so as to match the corresponding landmarks between the first brain image B1 and the standard brain image Bs.
- the first alignment is alignment by similarity transformation. Specifically, alignment is performed by translating, rotating, and resizing the standard brain image Bs.
- the dividing unit 22 performs similarity transformation on the standard brain image Bs so that the correlation between the landmarks included in the standard brain image Bs and the corresponding landmarks included in the first brain image B1 is maximized. Perform 1 alignment.
- the dividing unit 22 After performing the first alignment using the landmark in this manner, the dividing unit 22 performs the second alignment using the entire region between the first brain image B1 and the standard brain image Bs.
- the second alignment is alignment by non-linear transformation.
- alignment by nonlinear conversion alignment by converting a pixel position nonlinearly using functions, such as B spline and thin plate spline (Thin Plate Spline), is mentioned, for example.
- the dividing unit 22 performs the second alignment by non-linearly converting each pixel position of the standard brain image Bs after the first alignment to a corresponding pixel position included in the first brain image B1.
- the division unit 22 thus aligns the standard brain image Bs with the first brain image B1, and applies the boundaries of the divided regions in the standard brain image Bs to the first brain image B1, as shown in FIG. As shown in 5, the first brain image B1 is divided into a plurality of regions.
- the alignment unit 23 aligns a second brain image B2 including the subject's brain and the first brain image B1 that has a different imaging date and time from the first brain image B1. Specifically, after performing the third alignment using the landmark between the first brain image B1 and the second brain image B2, between the first brain image B1 and the second brain image B2 Perform a fourth alignment using the entire area of In the present embodiment, although the first brain image B1 is described as being aligned with the second brain image B2, the second brain image B2 may be aligned with the first brain image B1. Good.
- the alignment unit 23 extracts landmarks from the first brain image B1 and the second brain image B2.
- the extraction of the landmark may be performed in the same manner as the first alignment in the dividing unit 22.
- the alignment unit 23 performs the third alignment so that corresponding landmarks coincide between the first brain image B1 and the second brain image B2.
- the brain included in the first brain image B1 and the brain included in the second brain image B2 have the same size because the subject is the same. Therefore, in the present embodiment, rigid body alignment using only translation and rotation is performed as the third alignment.
- FIG. 6 is a diagram for explaining rigid body alignment.
- slice images G1 and G2 of corresponding tomographic planes in the first and second brain images B1 and B2 are shown for the sake of explanation.
- the alignment unit 23 corresponds to the ventricle 31 which is one of the landmarks of the slice image G1 of the first brain image B1 and the correspondence included in the slice image G2 of the second brain image B2.
- the first brain image B1 is translated and rotated to perform the third alignment which is the rigid body alignment so as to maximize the correlation with the ventricles 32.
- a third aligned first brain image B11 (slice image G11 in FIG. 6) is acquired.
- the alignment unit 23 After performing the third alignment using the landmark in this manner, the alignment unit 23 performs the fourth alignment using the entire region between the first brain image B1 and the second brain image B2. I do.
- the fourth alignment is alignment by non-linear transformation.
- the fourth alignment may be performed in the same manner as the second alignment in the dividing unit 22.
- the movement vector to the corresponding pixel position of the second brain image B2 in each pixel of the first brain image B1 is acquired.
- FIG. 7 is a diagram showing a movement vector. As shown in FIG. 7, at each pixel position of the brain in the first brain image B1, a movement vector Vm is acquired.
- the change amount acquisition unit 24 determines the first brain image B1 for at least one of the plurality of regions in the brain included in the second brain image B2 based on the alignment result in the alignment unit 23. Acquire the amount of change from the corresponding area in the included brain. In the present embodiment, the amount of change for each of the plurality of regions is acquired. In the present embodiment, the movement vector Vm is acquired at each pixel position of the brain included in the first brain image B1 by the alignment of the alignment unit 23. The change amount acquisition unit 24 classifies the movement vector Vm at each pixel position of the brain included in the first brain image B1 into each of a plurality of regions in the first brain image B1.
- the amount of change from the corresponding region in the brain included in the first brain image B1 is acquired for each of the plurality of regions in the brain included in the second brain image B2.
- the amount of change is the movement vector Vm of the corresponding pixel in the corresponding region.
- the change amount acquisition unit 24 calculates the volume change amount for each of a plurality of regions in the brain included in the second brain image B2.
- FIG. 8 is a diagram for explaining the calculation of the volume change amount.
- one region 40 included in the first brain image B1 is composed of three pixels 41, 42 and 43, and the pixels have not moved in the vertical direction in FIG.
- the movement vector V1 of the pixel 41 is 0.3 pixels in the left direction
- the movement vector V2 of the pixel 42 is the left direction
- the motion vector V3 of the pixel 43 has a size of 0.8 pixel in the left direction.
- the change amount acquisition unit 24 calculates the change amount of the pixel value of the region 40 as ⁇ 0.5 pixel.
- the change amount acquisition unit 24 actually calculates the change amounts of pixel values in the directions of the three axes of x, y, and z for each region in the first brain image B1. In the case where the amount of change is a negative value, the area shrinks, and in the case of a positive value, the area is expanded.
- the change amount acquisition unit 24 further calculates the volume change amount as follows. That is, for each region in the first brain image B1, the amounts of change calculated for the directions of the x, y, and z axes are added. Then, by dividing the added value obtained thereby by the total number of pixels in the corresponding area, the change rate of the area volume is calculated as the volume change amount. In this case, the volume change amount is expressed as a rate (for example, percentage) of change with respect to the volume of each region.
- the volume change also has a negative value if the region is atrophy, and a positive value if the region is dilated.
- the absolute value of the volume change amount which is a negative value is the atrophy rate of the brain.
- an added value obtained by adding the amounts of change calculated for the directions of the three axes x, y, and z may be calculated as the amount of volume change.
- the volume change amount is represented by the size of the pixel value, and is a negative value if the region is atrophy, and a positive value if the region is dilated.
- the volume per pixel (that is, one voxel) is known in advance. Therefore, the amount of change in volume may be calculated by adding the amounts of change calculated in the directions of the three axes x, y, and z, and multiplying the sum obtained by this with the volume per pixel. . In this case, the volume change amount is represented by the magnitude of the volume change amount.
- the change amount acquiring unit 24 compares the absolute value of the volume change amount, that is, the atrophy rate of the brain with the threshold value Th1 in the region where the value is negative, and the absolute value of the volume change amount is greater than the threshold value. Also, a large area is identified as an abnormal area and labeled. Here, the atrophy rate of the brain due to human aging is less than 1% a year, but it is about 1 to 3% in patients with dementia. For this reason, the change amount acquisition unit 24 sets, for example, the threshold value Th1 to ⁇ 1%, and identifies an area where the absolute value of the volume change amount is larger than the threshold value Th1 as an abnormal area.
- FIG. 9 is a view for explaining the display of the volume change amount.
- diagonal lines are given to the abnormal areas A10 and A11 among the plurality of areas of the brain, and labels L10 and L11 indicating the volume change amount are further given to the display 14.
- labels L10 and L11 indicate the absolute value of the volume change amount, that is, the atrophy rate of the brain.
- Each area may be displayed in different colors according to the magnitude of the volume change amount.
- the change amount in the brain that is, the area judged to have a large atrophy rate is displayed identifiably, but the presence or absence of the onset of dementia is diagnosed automatically, The result may be displayed.
- a discriminator is created by machine learning the amount of change for each region, that is, the atrophy rate and the presence or absence of occurrence of dementia, as teacher data (data with correct answer) for a plurality of patients in the past. Then, the amount of change for each new patient area calculated in the present embodiment, that is, the atrophy rate may be input to the discriminator to determine whether it is dementia or not.
- regions that are considered to have particularly large effects on a disease to be diagnosed may be handled differently from other regions. For example, in the case of identifiably displaying the region determined to have a high brain contraction rate as described above, the region considered to have a particularly large influence on the disease to be diagnosed is displayed distinguishably from other regions. It is also good. Also, as described above, in the case of automatically diagnosing the presence or absence of occurrence of dementia, weighting of teacher data is performed when learning a discriminator for a region considered to have a particularly large influence on a disease to be diagnosed. May be increased. In addition, hippocampus, cerebellum, and temporal lobe etc. are mentioned as a site
- FIG. 10 is a flowchart showing the process performed in the present embodiment.
- the image acquiring unit 21 acquires a first brain image B1 and a second brain image B2 including the brain of a subject whose imaging dates and times are different for the same subject (step ST1).
- the dividing unit 22 divides the brain included in the first brain image B1 into a plurality of areas by aligning the first brain image B1 with the standard brain image Bs divided into the plurality of areas. (Step ST2).
- the alignment unit 23 aligns the second brain image B2 and the first brain image B1 (step ST3).
- the change amount acquisition unit 24 is included in the first brain image B1 for at least one of a plurality of regions in the brain included in the second brain image B2 based on the alignment result.
- the amount of change from the corresponding region in the brain is obtained (step ST4), and the amount of volume change is calculated for at least one of a plurality of regions in the brain included in the second brain image B2 (step ST5).
- the display control unit 25 displays the volume change amount on the display 14 (step ST6), and the process ends.
- the second brain image B2 is aligned with the first brain image B1, but the first and second brain images B1 and B2 are images of the same subject. Even if the second brain image B2 is not deformed so much, alignment with the first brain image B1 can be performed with high accuracy. For this reason, as compared with the case where both the first brain image B1 and the second brain image B2 are aligned with the standard brain image Bs, each region of the brain included in the first brain image B1 and the second region It is possible to accurately obtain a slight amount of change between each region of the brain included in the brain image B2 of FIG. Therefore, it is possible to accurately acquire the amount of change between two brain images B1 and B2 having different imaging dates and times of the same patient, and further, the amount of volume change.
- the rigid registration is performed as the third registration, but the sizes of the brains contained in the first brain image B1 and the second brain image B2 may be different. is there.
- scaling may be performed as the third alignment in addition to the rigid alignment.
- volume change amount is calculated in the above embodiment, only the change amount of each region may be calculated.
- the second alignment is performed after the first alignment using the landmarks in the dividing unit 22.
- the second alignment that is, the alignment by nonlinear conversion is performed. May be performed.
- the fourth alignment is performed after the third alignment using the landmarks in the alignment unit 23.
- the fourth alignment that is, the alignment by nonlinear conversion is performed. You may do it only.
- the standard brain image Bs and the first brain image Alignment may be performed using a partial area of B1.
- alignment may be performed using only individual divided regions in the brain.
- the alignment using the entire area of the first brain image B1 and the second brain image B2 is performed, but the first brain image B1 and the second brain image B1 are not Alignment may be performed using a partial region of two brain images B2. For example, alignment may be performed using only individual divided regions in the brain.
- the MRI image of a test object is used as a medical image
- the volume change amount of each region can be accurately acquired.
- the alignment After performing the first alignment using the landmark and then performing the second alignment, after performing the alignment using the area where the alignment is easy to be performed, the alignment is further performed. Become. Therefore, the alignment between the first brain image and the standard brain image can be efficiently performed.
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Abstract
Description
第1の脳画像と撮影日時が異なる、上記被検体の脳を含む第2の脳画像と、第1の脳画像とを位置合わせする位置合わせ部と、
第1の脳画像と第2の脳画像との位置合わせの結果に基づいて、第2の脳画像に含まれる脳における複数の領域のうちの少なくとも1つの領域についての、第1の脳画像に含まれる脳における対応する領域からの変化量を取得する変化量取得部とを備える。
第1の脳画像と撮影日時が異なる、被検体の脳を含む第2の脳画像と、第1の脳画像とを位置合わせし、
第1の脳画像と第2の脳画像との位置合わせの結果に基づいて、第2の脳画像に含まれる脳における複数の領域のうちの少なくとも1つの領域についての、第1の脳画像に含まれる脳における対応する領域からの変化量を取得する。
記憶された命令を実行するよう構成されたプロセッサとを備え、プロセッサは、
被検体の脳を含む第1の脳画像と複数の領域に分割された標準脳画像とを位置合わせすることにより、第1の脳画像に含まれる脳を複数の領域に分割し、
第1の脳画像と撮影日時が異なる、被検体の脳を含む第2の脳画像と、第1の脳画像とを位置合わせし、
第1の脳画像と第2の脳画像との位置合わせの結果に基づいて、第2の脳画像に含まれる脳における複数の領域のうちの少なくとも1つの領域についての、第1の脳画像に含まれる脳における対応する領域からの変化量を取得する処理を実行する。
11、メモリ12およびストレージ13を備えている。また、医用画像処理装置1には、ディスプレイ14、並びにキーボードおよびマウス等の入力部15が接続されている。なお、ディスプレイ14が表示部に対応する。
2 3次元画像撮影装置
3 画像保管サーバ
4 ネットワーク
11 CPU
12 メモリ
13 ストレージ
14 ディスプレイ
15 入力部
21 画像取得部
22 分割部
23 位置合わせ部
24 変化量取得部
25 表示制御部
31,32 脳室
40 領域
41,42,43 画素
B1 第1の脳画像
B2 第2の脳画像
Bs 標準脳画像
G1,G2,G11 スライス画像
L10,L11 ラベル
Vm 移動ベクトル
Claims (10)
- 被検体の脳を含む第1の脳画像と複数の領域に分割された標準脳画像とを位置合わせすることにより、前記第1の脳画像に含まれる脳を複数の領域に分割する分割部と、
前記第1の脳画像と撮影日時が異なる、前記被検体の脳を含む第2の脳画像と、前記第1の脳画像とを位置合わせする位置合わせ部と、
前記第1の脳画像と前記第2の脳画像との位置合わせの結果に基づいて、前記第2の脳画像に含まれる脳における前記複数の領域のうちの少なくとも1つの領域についての、前記第1の脳画像に含まれる脳における対応する領域からの変化量を取得する変化量取得部とを備えた医用画像処理装置。 - 前記変化量取得部は、前記第2の脳画像に含まれる脳における前記複数の領域のうちの少なくとも1つの領域についての容積変化量を算出する請求項1に記載の医用画像処理装置。
- 前記容積変化量を表示部に表示する表示制御部をさらに備えた請求項2に記載の医用画像処理装置。
- 前記位置合わせ部は、前記第1の脳画像に含まれる脳および前記第2の脳画像に含まれる脳における対応する領域間において、対応する画素位置の移動ベクトルを前記変化量として取得する請求項1から3のいずれか1項に記載の医用画像処理装置。
- 前記分割部は、前記第1の脳画像および前記標準脳画像間でのランドマークを用いた第1の位置合わせを行った後に、前記第1の脳画像および前記標準脳画像間での第2の位置合わせを行う請求項1から4のいずれか1項に記載の医用画像処理装置。
- 前記第1の位置合わせは相似変換による位置合わせであり、前記第2の位置合わせは非線形変換による位置合わせである請求項5に記載の医用画像処理装置。
- 前記位置合わせ部は、前記第1の脳画像および前記第2の脳画像間でのランドマークを用いた第3の位置合わせを行った後に、前記第1の脳画像および前記第2の脳画像間での第4の位置合わせを行う請求項1から6のいずれか1項に記載の医用画像処理装置。
- 前記第3の位置合わせは剛体位置合わせであり、前記第4の位置合わせは非線形変換による位置合わせである請求項7に記載の医用画像処理装置。
- 被検体の脳を含む第1の脳画像と複数の領域に分割された標準脳画像とを位置合わせすることにより、前記第1の脳画像に含まれる脳を複数の領域に分割し、
前記第1の脳画像と撮影日時が異なる、前記被検体の脳を含む第2の脳画像と、前記第1の脳画像とを位置合わせし、
前記第1の脳画像と前記第2の脳画像との位置合わせの結果に基づいて、前記第2の脳画像に含まれる脳における前記複数の領域のうちの少なくとも1つの領域についての、前記第1の脳画像に含まれる脳における対応する領域からの変化量を取得する医用画像処理方法。 - 被検体の脳を含む第1の脳画像と複数の領域に分割された標準脳画像とを位置合わせすることにより、前記第1の脳画像に含まれる脳を複数の領域に分割する手順と、
前記第1の脳画像と撮影日時が異なる、前記被検体の脳を含む第2の脳画像と、前記第1の脳画像とを位置合わせする手順と、
前記第1の脳画像と前記第2の脳画像との位置合わせの結果に基づいて、前記第2の脳画像に含まれる脳における前記複数の領域のうちの少なくとも1つの領域についての、前記第1の脳画像に含まれる脳における対応する領域からの変化量を取得する手順とをコンピュータに実行させる医用画像処理プログラム。
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