JP2019088577A - Information processing device, information processing system, information processing method, and program - Google Patents

Abstract

To assist a user in appropriately evaluating a difference image.SOLUTION: An information processing device acquires first supplementary information that is information supplementary to a first medical image, and second supplementary information that is information supplementary to a second medical image, generates third supplementary information that is information supplementary to a difference image generated by using the first medical image and the second medical image on the basis of the first supplementary information and the second supplementary information, associates the third supplementary information with the difference image, and outputs it.SELECTED DRAWING: Figure 10

Description

  The disclosure of the present specification relates to an information processing device, an information processing system, an information processing method, and a program.

  A doctor may observe while comparing a plurality of medical images in medical care. Patent Document 1 discloses that a difference image which is a difference between an image captured in the past and a current image is generated.

Japanese Patent Application Laid-Open No. 2002-190010

  When observing the generated difference image, information on the original medical image may be required.

  An information processing apparatus according to an embodiment of the present invention acquires first incidental information which is information incidental to a first medical image and second incidental information which is information incidental to a second medical image. An attached difference image generated using the first medical image and the second medical image based on the first acquisition unit, the first incidental information, and the second incidental information It is characterized by comprising: second acquisition means for generating third incidental information which is information; and output means for outputting the third incidental information in association with the difference image.

  According to the information processing apparatus according to the embodiment of the present invention, when observing a difference image, it is possible to read information related to an original medical image from incidental information of the difference image.

It is a figure showing an example of apparatus composition of an information processing system concerning a 1st embodiment. It is a flow figure showing an example of the whole processing procedure in a 1st embodiment. It is a figure which shows an example of the display for selecting a medical image on a test | inspection list | wrist. It is a figure which shows an example of the expression format of the difference information according to the property of incidental information. It is a figure which shows an example of a display of the difference information linked | related with the difference image. It is a figure showing an example of apparatus composition of an information processing system concerning a 2nd embodiment. It is a flow figure showing an example of the whole processing procedure in a 2nd embodiment. It is a figure which shows an example of the display for selecting a difference image on a test | inspection list | wrist. It is a figure which shows an example of the item of incidental information of a difference image, and the attribute of description content. It is a figure which shows an example of the item of incidental information of a difference image, and a specific description content. It is a figure showing an example of apparatus composition of an information processing system concerning a 3rd embodiment. It is a flow figure showing an example of the whole processing procedure in a 3rd embodiment. It is a figure which shows an example of a display of the reliability linked | related with the difference image. It is a figure showing an example of the hardware constitutions of the information processor concerning an embodiment of the present invention. It is a figure which shows an example of the screen displayed based on the information output based on the information processing apparatus which concerns on 2nd Embodiment.

  Hereinafter, preferred embodiments of an information processing apparatus, a control method thereof and a program according to the present invention will be described in detail with reference to the attached drawings. However, the scope of the invention is not limited to the illustrated example.

First Embodiment
The information processing apparatus according to the present embodiment displays information related to the difference image together with the difference image between two medical images. More specifically, the information processing apparatus according to the present embodiment generates difference information on the difference between incidental information incidental to two medical images, and displays the information in association with a difference image between medical images. Thereby, the user can observe the difference image more appropriately by presenting the difference of the incidental information to the user in addition to the difference of the image between the two medical images.

  FIG. 1 shows the configuration of an information processing system according to the present embodiment. As shown in the figure, the information processing apparatus 100 in the present embodiment is connected to the data server 130 and the image processing server 140 via the network 120.

  The data server 130 holds a plurality of medical images, and the first and second medical images held by the data server 130 capture an object in advance under different conditions (different modalities, imaging modes, date and time, etc.) It is a medical image obtained by The modality for imaging a medical image may be an MRI apparatus, an X-ray CT apparatus, a three-dimensional ultrasonic imaging apparatus, a photoacoustic tomography apparatus, PET / SPECT, an OCT apparatus, a digital radiography apparatus, and the like. The first and second medical images may be any images as long as they are targets for generating a difference image. For example, the first and second medical images may be captured simultaneously at different modalities and different imaging modes. In addition, the first and second medical images may be images obtained by imaging the same patient at the same modality, the same physical position, and different dates and times for follow-up observation.

  When the first and second medical images are three-dimensional tomographic images, the medical images are three-dimensional images configured as a set (tomographic image group) of two-dimensional tomographic images (slice images). The position and orientation of each of the two-dimensional tomographic images constituting the three-dimensional image are converted to a reference coordinate system (coordinate system in the space based on the subject) and then stored in the data server 130. Do. The first and second medical images are input to the information processing apparatus 100 in accordance with an instruction of a user who operates the instruction unit 150.

  Here, the information held by the medical image will be described. The medical image holds supplementary information in addition to image data composed of pixel values. The incidental information represents various information on the medical image. The incidental information includes, for example, patient ID, patient name, examination ID, examination date (acquisition date when medical image was acquired), identification information of series of tomographic images (series ID), imaging date, modality, manufacturer, etc. . In addition, the incidental information also includes, for example, information such as a reconstruction function at the time of imaging, an examination site, the number of two-dimensional tomographic images constituting the medical image (the number of slices), the thickness (slice thickness), the image size, and the pixel interval. Including. That is, the incidental information is information configured by at least one item among the plurality of items described above.

  The incidental information in the present embodiment is recorded in the medical image as header information of the medical image. The incidental information is recorded as, for example, data elements defined in Digital Imaging and Communication in Medicine (DICOM), which is an example of a medical image standard. The incidental information is not limited to such information, and may be any information as long as it relates to a medical image. Further, since the incidental information is incidental to the medical image, when the medical image data is input / output, it is input / output in a form included in the medical image together with the image data. Furthermore, the incidental information may be stored in a file or database different from the medical image. In this case, the information processing apparatus 100 may access the file or the database as needed and refer to the incidental information.

  The image processing server 140 is an apparatus installed in a hospital or in the cloud as a server, and receives an image processing request in response to a processing request. Specifically, the image processing server 140 receives, from the information processing apparatus 100, the first and second medical images to be processed for difference image generation in response to a request for difference image generation from the information processing apparatus 100. . Note that the image processing server 140 may receive the first and second medical images directly from the data server 130. When the first and second medical images are received, the image processing server 140 positions the first medical image to match the second medical image (so that the pixels representing the same part of the subject correspond). Perform alignment processing. Then, the image processing server 140 generates a difference image by acquiring the difference between the pixel values of the two images after alignment, and outputs the difference image to the information processing apparatus 100.

  Here, the second medical image is an image serving as a reference for alignment, and the second medical image is referred to as a reference image (or a reference image). On the other hand, the first medical image is an image which is geometrically transformed toward the second image, and the first medical image is referred to as a comparison image (or floating image).

  The information processing apparatus 100 receives a request for processing by the user from the instruction unit 150, performs information processing, and outputs a processing result to the display unit 160. The information processing apparatus 100 functions as a terminal device for image interpretation operated by a user such as a doctor Do. The information processing apparatus 100 exchanges data with the data server 130 and the image processing server 140 and requests processing.

  A concrete example will be described. The information processing apparatus 100 includes first and second medical images (for example, a past image captured at a past examination of the same subject and a current image captured at a later examination than the past image) acquired from the data server 130. It is transmitted to the image processing server 140 as a target of differential image generation. Also, the information processing apparatus 100 receives the generated difference image from the image processing server 140. Then, the information processing apparatus 100 displays the difference image on the display unit 160 together with the first medical image and the second medical image.

  The information processing apparatus 100 is configured by the components described below. The instruction acquisition unit 101 acquires an instruction from the instruction unit 150 by the user. The medical image acquisition unit 102 acquires information of the first and second medical images input to the information processing apparatus 100. The difference image acquisition unit 103 acquires a difference image generated by the image processing server 140 using the first medical image and the second medical image. The difference information generation unit 104 generates difference information representing the difference between the incidental information of the first and second medical images. The display control unit 105 performs control to output the acquired difference image and difference information to the display unit 160.

  The instruction unit 150 is a device for transmitting an instruction from the user to the information processing apparatus 100. Instruction unit 150 is, for example, a mouse or a keyboard. Specifically, the instruction unit 150 transmits, to the instruction acquisition unit 101, a signal related to the click of the mouse or the depression of the keyboard received from the user.

  The display unit 160 displays an image, incidental information, and the like for the doctor to interpret. The display unit 160 is, for example, a liquid crystal display (LCD) or a cathode-ray tube (CRT). Specifically, the display unit 160 displays a cross-sectional image extracted from each of the first medical image, the second medical image, and the difference image acquired from the information processing apparatus 100. The display unit 160 also displays a GUI for acquiring an instruction from a user such as a doctor. The user can freely switch the cross-sectional image of the first medical image, the second medical image, and the difference image being displayed to another cross-sectional image in the depth direction of the cross-sectional image using the above GUI . In addition, the display unit 160 displays a GUI by which a user such as a doctor selects a medical image from the examination list of the patient.

  In the information processing system according to the present embodiment, the information processing apparatus 100 and the image processing server 140 are installed at physically separated places and connected via a network, but the apparatus configuration is not necessarily limited thereto. It does not mean that For example, the information processing apparatus 100 and the image processing server 140 may be configured as an integrated apparatus. In this case, input / output of data between the information processing apparatus 100 and the image processing server 140 via the network can be replaced with input / output of data in the same apparatus. Specifically, the information processing apparatus 100 transmits the first and second medical images to be subjected to image subtraction processing from the information processing apparatus 100 to the image processing server 140, and the difference image generated by the image processing server 140. The processing received above replaces data input / output within the same device.

  FIG. 14 is a diagram illustrating an example of a hardware configuration of the information processing apparatus 100. The information processing apparatus 100 is, for example, a computer. The information processing apparatus 100 includes a CPU 1401, a ROM 1402, a RAM 1403, a storage device 1404, a USB 1405, a communication circuit 1406, and a graphics board 1407. These are communicably connected by BUS. The BUS is used to transmit and receive data between connected hardware and to transmit an instruction from the CPU 1401 to other hardware.

  A CPU (Central Processing Unit) 1401 is a control circuit that integrally controls the information processing apparatus 100 and each unit connected thereto. The CPU 1401 executes control by executing a program stored in the ROM 1402. The CPU 1401 also executes a display driver, which is software for controlling the display unit 160, and performs display control on the display unit 160. Furthermore, the CPU 1401 performs input / output control on the instruction unit 150.

  A ROM (Read Only Memory) 1402 stores a program and data in which a procedure of control by the CPU 1401 is stored. The ROM 1402 stores a boot program of the information processing apparatus 100 and various initial data. In addition, various programs for realizing the processing of the information processing apparatus 100 are stored.

  A RAM (Random Access Memory) 1403 provides a storage area for work when the CPU 1401 performs control by an instruction program. The RAM 1403 has a stack and a work area. The RAM 1403 stores a program for executing processing in the information processing apparatus 100 and each unit connected thereto, and various parameters used in image processing. The RAM 1403 stores a control program executed by the CPU 1401 and temporarily stores various data when the CPU 1401 executes various controls.

  The storage device 1404 is an auxiliary storage device that stores various data such as an ultrasound image and a photoacoustic image. The storage device 1404 is, for example, a hard disk drive (HDD) or a solid state drive (SSD).

  A USB (Universal Serial Bus) 1405 is a connection unit connected to the instruction unit 150.

  A communication circuit 1406 is a circuit for performing communication with each component of the system and various external devices connected to the network. The communication circuit 1406 stores, for example, information to be output in a transfer packet, and outputs the information to an external apparatus via the network by a communication technology such as TCP / IP. The information processing apparatus 100 may have a plurality of communication circuits in accordance with a desired communication mode.

  The graphics board 1407 includes a graphics processing unit (GPU) and a video memory. The GPU performs, for example, an operation related to reconstruction processing for generating a photoacoustic image from a photoacoustic signal.

  A high definition multimedia interface (HDMI (registered trademark)) 1408 is a connection unit connected to the display unit 160.

  The CPU 1401 and the GPU are examples of a processor. The ROM 1402, the RAM 1403, and the storage device 1404 are examples of a memory. The information processing apparatus 100 may have a plurality of processors. In the first embodiment, when the processor of the information processing apparatus 100 executes a program stored in the memory, the functions of the units of the information processing apparatus 100 are realized.

  Further, the information processing apparatus 100 may have a CPU or a GPU that performs specific processing exclusively, or an application specific integrated circuit (ASIC). The information processing apparatus 100 may have an FPGA (Field-Programmable Gate Array) in which specific processing or all processing is programmed.

  FIG. 2 is a flowchart showing the overall processing procedure performed by the information processing apparatus 100.

(S2010) (obtain an image selection instruction)
In step S2010, the instruction acquisition unit 101 acquires an instruction for image selection by the user from the instruction unit 150. Specifically, from the examination list displayed on the display unit 160, the instruction acquisition unit 101 performs a first medical image (comparison image) and a second medical image (reference image) by which the user generates a difference image. Get an indication of the choice of. Then, the instruction acquisition unit 101 outputs instruction information for image selection to the medical image acquisition unit 102.

  FIG. 3 is a view showing an example of a display for selecting a medical image on the examination list. Reference numeral 301 denotes an examination list in which medical images obtained in a plurality of examinations performed on a specific patient are listed. In this embodiment, the user can select an item (for example, “CT medical image” of examination date: 2014/10/25, etc.) displayed on the display unit 160 by mouse click or the like to cope with the item. Medical images to be selected are selected.

  302 and 303 in FIG. 3 represent the case where the user selects two medical images (first and second medical images) on the examination list. Here, the first medical image 302 represents a past image by CT examination (examination date: 2014/10/25), and the second medical image 303 represents a current image by CT examination (examination date: 2017/03/02) ing. In 302 and 303, the text is highlighted to make it clear that the image has been selected. In the present embodiment, of the two medical images selected by the user, the medical image with the newer imaging date (current image) is the second medical image (reference image), and the medical image with the older imaging date ( The past image) is taken as a first medical image (comparison image). Other than that, the medical image selected by the user first may be the second medical image (reference image), and the medical image selected later may be the first medical image (comparison image). Alternatively, the user may directly specify the reference image and the comparison image.

(S2020) (acquire medical image)
In step S2020, the medical image acquisition unit 102 acquires the first and second medical images from the data server 130 based on the instruction for medical image selection acquired by the instruction acquisition unit 101. Here, the medical image acquisition unit 102 acquires the first incidental information which is incidental information incidental to the first medical image and the second incidental information incidental to the second medical image. Ru. Then, the medical image acquisition unit 102 outputs the acquired first and second medical images to the difference image acquisition unit 103, the difference information generation unit 104, and the display control unit 105.

(S2030) (acquire a difference image)
In step S2030, the difference image acquisition unit 103 outputs the first and second medical images to the image processing server 140, and requests generation of a difference image. Thereafter, the difference image acquisition unit 103 acquires a difference image generated by the image processing server 140 using the first and second medical images. Then, the difference image acquisition unit 103 outputs the acquired difference image to the difference information generation unit 104 and the display control unit 105. That is, it corresponds to an example of a difference image acquisition unit that acquires difference images generated using a plurality of medical images.

  As described above, when the information processing apparatus 100 and the image processing server 140 are configured as an integrated apparatus, the difference image acquisition unit 103 plays a role of generating a difference image in the image processing server 140. Specifically, the difference image acquisition unit 103 performs alignment processing so that the first medical image matches the second medical image, and acquires the difference between the pixel values of the two images after alignment. To generate a difference image. Here, the alignment method may be any known method. When it can be assumed that the first medical image and the second medical image are imaging the same part of the subject at the same coordinates, alignment processing between the images is not necessarily required. Also, the difference image may be generated using three or more medical images.

(S2040) (Generation of difference information between incidental information of medical image)
In step S2040, the difference information generation unit 104 generates difference information representing the difference between the incidental information of the first and second medical images. At this time, the difference information is a difference for each item constituting the first incidental information which is information incidental to the first medical image and the second incidental information which is information incidental to the second medical image. It is composed of the information Then, the difference information generation unit 104 outputs the generated difference information to the display control unit 105. Below, the concrete content and the acquisition method of difference information are shown.

  FIG. 4 is a diagram showing an example of the expression format of the difference information of the incidental information. In the present embodiment, the incidental information is classified into, for example, a group A and a group B. Group A is a group of incidental information to compare whether or not the values match. Group B is a group of incidental information in which values are numerical values and the degree of coincidence of numerical values is compared.

  The item of incidental information included in the group A is, for example, an item of incidental information in which difference information can not be represented by a numerical value. However, for items that can be expressed only by combinations of numbers, such as IDs, even in such cases, there is no point in comparing the values of numbers (the size of the difference in numbers between IDs has no meaning), We treat it here as an item that can not be expressed numerically. The information processing apparatus 100 expresses, as difference information of incidental information, a binary value indicating whether the values are the same or different (a state of “the same value is also included in the difference information). As a specific example of the items included in the group A, the item 401 in FIG. 4 can be mentioned. That is, patient ID, patient name, examination ID, series ID, reconstruction function at imaging, imaging sequence, imaging state, examination position, examination site, modality, maker, model name, examination organization and the like. For example, when the patient ID is the same between the incidental information of the first and second medical images (eg, the first medical image: "0123", the second medical image: "0123"), the difference information is : Expressed as "identical". On the other hand, when the patient ID is different (eg, the first medical image: “0123”, the second medical image: “2345”), the difference information: “different” is expressed.

  In the item of incidental information included in the group B, the difference information is represented by a numerical value. The group B is further classified into a group B1 and a group B2. In the item of incidental information included in the group B1, a difference between numerical values is acquired as difference information. Specific examples of the items included in the group B1 include the item 402, that is, the examination date, examination time, imaging date, imaging time, and the like. For example, an item representing a date and time such as an examination date makes sense in the difference on the absolute numerical axis of time. For example, the difference between the examination dates (acquisition dates) allows the user to grasp how long the time interval was between the two medical images, and a difference value depicted in the difference image occurred in a short time ( Example: "3 months") It can be understood whether it occurred for a long time (eg "5 years"). The group B1 can be regarded as, for example, an item having a meaning in the absolute difference, and the information processing apparatus 100 acquires the difference between the numerical values of the incidental information as the difference information.

  In the item of incidental information included in the group B2, the degree of coincidence between numerical values is acquired as difference information. Specific examples of the items included in the group B2 include the items 403, that is, slice thickness, pixel size, pixel interval, number of slices, image size, patient age and the like. Taking the item of slice thickness as an example, the information indicating the relative difference between the slice thicknesses of the first medical image and the second medical image is the difference information of the item. Specifically, when the slice thicknesses of the first and second medical images are “1 mm” and “2 mm”, respectively, the difference in value is “1 mm”. However, the difference "1 mm" in slice thickness alone does not indicate whether the difference between the original two medical images is large or small. For example, when the slice thickness of the above-mentioned medical image is “1 mm” and “2 mm” respectively, the difference “1 mm” between them occupies a large ratio to the slice thickness of the original medical image (1.0 and 2.0 times respectively). However, when the slice thickness of the medical image is “4 mm” and “5 mm” respectively, the difference “1 mm” between them does not occupy a large ratio to the slice thickness of the original medical image Are 0.25 and 0.2 times respectively). In this way, with regard to items included in the B2 group, information that can be grasped to what extent a difference is relatively between medical images, in other words, to what extent a match is relatively made, is used as difference information.

In the present embodiment, the degree of coincidence of the values of the incidental information is used as the difference information of the items included in the B2 group. Specifically, the matching degree M is obtained based on the following equation (1).
M = (smaller value) / (larger value) (1)

  Applying the above example of slice thickness to Equation (1), if the slice thickness is “1 mm” and “2 mm”, respectively, the coincidence S = “1 mm” / “2 mm” = 0.50 (50%) Become. When the slice thickness is “4 mm” and “5 mm”, respectively, the matching degree M = “4 mm” / “5 mm” = 0.80 (80%). The degree of coincidence M allows the user to comprehend the relative degree of coincidence. That is, the user can grasp how relatively there is a difference (the former differs by 50% and the latter differs by only 20%). Also, as another example, with regard to the number of slices, the image size, and the pixel interval, the degree of coincidence can be obtained by the same calculation as that of equation (1). In addition, the acquisition method of the agreement degree M is not limited to Numerical formula (1), As long as the relative agreement degree of two values can be quantified, you may use any acquisition method. For example, a value obtained by dividing “absolute value of difference between two values” by “average value of two values” may be M.

  In FIG. 4, the examination site is listed as an example of the items included in the B group. The item of the examination site is usually expressed as a word representing a body part such as "CHEST" or "HEAD". The difference information generation unit 104 acquires, for example, the matching degree of the examination site based on the result of the alignment of the first medical image and the second medical image. In step S2030, the image processing server 140 aligns the first and second medical images, and as a result, generates a difference image by acquiring the difference between the pixel values of the common area of the two. That is, the image processing server 140 can acquire an area (other areas) not common to the common area (difference image) using the first and second medical images.

The difference information generation unit 104 uses the following formula (2) as a formula for obtaining the degree of coincidence of the examination site between the first and second medical images.
M = (region 1 / region 2 / (region 1 / region 2)) (2)

  In equation (2), region 1 and region 2 represent three-dimensional image regions of the first and second medical images, respectively. Equation (2) represents Jaccard index, which is a method of determining the degree of coincidence between area 1 and area 2. At this time, (region 1 / region 2) of Expression (2) is a common region (difference image) between medical images and is known. Therefore, since the information of (region 1 / region 2) can be acquired from the information of region 1, region 2 and (region 1 / region 2), the equation (2) can be calculated. The degree of coincidence M may be another method such as a Dice coefficient or a Simpson coefficient as long as the degree of coincidence between the region 1 and the region 2 can be calculated.

Although the coincidence M of the values of the incidental information is applied as the difference information between the incidental information in the above description, the coincidence of the values of the incidental information may be applied. Mismatch degree M 'is
M '= 1-M
You can get it by.

  The difference information generation unit 104 of the present embodiment acquires difference information of each item of the incidental information exemplified in 401, 402, and 403 of FIG. However, incidental information for acquiring difference information is not limited to this, and any information incidental to a medical image may be used. Further, instead of acquiring the difference information for all the items of the incidental information, the configuration may be such that the difference information is acquired for only a part of the designated items of the incidental information. For example, an item that can be related to the quality of the difference image can be specified in advance, and only difference information of the specified item can be acquired.

  For example, the designated item for acquiring difference information may be changed according to the type of medical image. For example, when the modalities for imaging medical images are CT and MRI, incidental information on imaging parameters of medical images is different. In the case of CT, CT-specific incidental information such as a reconstruction function is present, and in the case of MRI, no corresponding incidental information is present. Therefore, the difference information generation unit 104 refers to modality information of incidental information of the medical image, and generates difference information of designated items specific to the modality according to the type of modality. At this time, the difference information generation unit 104 generates difference information by the above-described method only when the type of modality matches between the first and second medical images. When the types of modality do not match, the difference information generation unit 104 generates difference information of only general items (examination date, pixel size, patient age, etc.) that do not depend on the modality.

  In addition, although an example in which classification is made into group A and group B according to the method of acquiring difference information has been described, the method of classification and the method of acquiring difference information are not limited to the example shown in FIG. Each of the items classified into the items 401 to 403 may be changed based on medical knowledge, or may be arbitrarily changed by the doctor.

(S2050) (The difference information is displayed in association with the difference image)
In step S2050, the display control unit 105 causes the display unit 160 to display the first and second medical images acquired from the medical image acquisition unit 102. Further, the display control unit 105 causes the display unit 160 to display the difference information acquired from the difference information generation unit 104 in association with the difference image acquired from the difference image acquisition unit 103. That is, it corresponds to a display control unit that causes the display unit to display the difference information in association with the difference image.

  FIG. 5 is a view showing an example of display of difference information associated with the difference image. In FIG. 5, reference numerals 501 and 502 denote cross-sectional images of the first and second medical images, respectively. In FIG. 5, the first medical image and the second medical image related to the same subject represent a reference image. 505 depicted in the cross-sectional image 501 and 506 depicted in the cross-sectional image 502 each represent an object. In FIG. 5, the cross-sectional images 501 and 502 are cross-sectional images obtained by cutting out the image in a direction (axial direction) in which the torso of the subject is cut in a row, and 505 and 506 indicate the torso of the subject displayed as a slice. Represent. When the torso 505 and 506 of the subject are compared, it can be seen that there is a deviation in the position and orientation and the shape of the comparison image and the reference image.

  Furthermore, 508 represents a lesion that has occurred on the reference image. Furthermore, reference numeral 507 denotes a cross-sectional image of the difference image. The cross-sectional image 503 is a cross-sectional image of a difference image (of the same cross-sectional position) corresponding to the cross-sectional image 502. Reference numeral 507 denotes information of the difference value on the cross-sectional image 503 corresponding to the vicinity of the contour of the subject body on the cross-sectional image 502. The contour may be depicted as a visible artifact according to the change in physical size of the subject and the accuracy of the alignment. Reference numeral 509 denotes information of the difference value on the cross-sectional image 503 corresponding to the lesion 508 on the cross-sectional image 502. The user can easily grasp the lesion generated as the temporal change between the reference image and the comparison image by confirming the lesion 509 on the cross-sectional image 503 of the difference image. The display of medical images and difference images may use any known method other than the above. For example, an MPR (Multi-Planar Reconstruction) image or a MIP (Maxmum Intensity Projection) image of a medical image or a difference image may be displayed. Also, the difference image and the second medical image may be displayed in a superimposed manner.

  Reference numerals 510 and 511 denote incidental information (at least a part of items included in incidental information) of a part of the first and second medical images. In 510 and 511, a part of additional information selected from all the additional information of the medical image is displayed. The items to be displayed superimposed on the medical image may be specified by a setting file stored in advance, or may be specified by displaying a setting screen and receiving a selection of items to be displayed from the user. In addition, all incidental information of the medical image may be superimposed and displayed on the medical image. Reference numeral 512 denotes difference information between incidental information of the first and second medical images displayed in association with the difference image. This difference information is the difference information corresponding to the displayed item among the items included in the incidental information of the first and second medical images. As described above, by displaying the difference information between the incidental information superimposed on the difference image, the user can easily associate and confirm the difference information between the difference value on the difference image and the incidental information.

  The display control unit 105 may cause the difference information to be popped up in response to the information processing apparatus 100 detecting an operation of selecting the difference image 503 such as mouse-on or click operation on the difference image 503. The difference information may be displayed in an area different from the area in which the image is displayed. In this case, the areas may be displayed in association with one another by line segments or the like. The form in which the difference image and the difference information are displayed in association with each other is not limited to the display form shown in the present embodiment. Further, in the example shown in FIG. 5, the difference information of the items corresponding to the incidental information 510 and 511 is displayed as the difference information 512. Thereby, the difference information between incidental information can be matched with the difference value on a difference image, and can be confirmed. As the item for displaying difference information, an item that may be related to the quality of the difference image may be designated in advance from the items of the supplementary information 510 and 511, and only the selection item may be displayed. . Further, an item for displaying difference information may be designated independently of the display item of incidental information in a medical image.

  In the present embodiment, the display mode of the difference information is changed between the item in which the incidental information is “the same” and the item in which the incidental information is “different” in the difference information 512. That is, it corresponds to an example of the display control means characterized in that the display form is different between the item in which the difference exists and the item in which the difference does not exist. The incidental information "identical" means that the value of the incidental information is "identical" between the two incidental information in the case where the value of the incidental information can not be expressed as a numerical value. On the other hand, in the case where the value of the incidental information can be represented by a numerical value, it means that the degree of coincidence of the values of the two incidental information is "1.0 (100%)". The “different” incidental information means that the above “identical” is not the case.

  As a method of changing the display mode, as in the difference information 512 illustrated in FIG. 5, the item “different” in the accompanying information can be emphasized and displayed more than the item “same”. As another method, it is possible to display only the item "different" in the incidental information, and not to display the item in the case of "identical". Thereby, the user can easily grasp the item in which the difference occurs in the difference information. In the example of FIG. 5, it is easily understood from the difference information 512 that the difference value of the lesion 509 on the displayed difference image is generated in the period of the examination date of 2 years, 4 months and 5 days. As a result, the user can more easily grasp the change over time of the lesion.

  The user can also judge the quality of the difference image according to the size of the difference between the examination dates. If the difference between the examination dates is large, the change of the subject during that period becomes large, and thus the deviation of the anatomical structure depicted between the medical images may be large. Therefore, the alignment accuracy between medical images having large deviations may be degraded, and the quality of the difference image may also be degraded. In addition, although the difference between the examination dates can be determined by the user from the examination dates displayed on the cross-sectional images 501 and 502 of the comparison image and the reference image, the time and effort can be reduced in this embodiment. .

  Further, from the difference information 512, it can be easily understood that the cross-sectional image 503 of the displayed difference image is generated between medical images having a matching degree of slice thickness of 20%. As a result, the difference image is generated from those with greatly different resolutions in the depth method of the cross-sectional image, and there is a possibility that noise due to image processing between different resolutions may be mixed in the difference image. Understand that it may affect the quality of This can reduce the risk of mistaking noise as a lesion.

  Reference numeral 504 denotes a difference information list in which the difference information is listed. In the present embodiment, information on items of incidental information other than the difference information 512 displayed in the cross-sectional image 503 is presented. By displaying the difference information list 504, the entire generated difference information can be grasped. The difference information list 504 may be always displayed, or may be displayed for the first time when the user performs an operation input on an icon (not shown) such as “detail display of difference information”. It is also good. As a result, while the difference information list display is not designated, another display object can be displayed on the display area for the effective use of the area. Further, the difference information list 504 may be displayed in a pop-up window or the like.

  Note that 513 on the difference information list 504 indicates the difference information of each item, and 514 and 515 indicate incidental information of the first and second medical images (comparison image and reference image) from which the difference information of each item is derived. Represent. In the present embodiment, as in the difference information 512, the display mode of the difference information is changed between the item in which the incidental information is “identical” and the item in which the incidental information differs in the difference information 513. As for the way of changing the display mode, as in the case of the difference information 512, the item “different” in the accompanying information is emphasized and displayed more than the item “same”. Alternatively, it may be determined whether the incidental information of each item is "different" or "identical", and only the "different" item may be displayed, and the "identical" item may not be displayed. As a result, the user can easily grasp how many items in which the difference occurs in the difference information and how much the respective items differ. If the number of items causing a difference is large and the degree of difference is large, the difference in various conditions between the two medical images that are the basis of the difference image is large, so the quality of the difference image may be low. The user can judge that there is a sex. On the other hand, when the number of items having a difference is small and the degree of difference is small, the difference between various conditions between the two medical images that are the sources of the difference image is small, so the quality of the difference image may be high. The user can judge that there is

  The process of the information processing apparatus 100 is performed as described above. The criterion for changing the display mode of the difference information may not be whether the incidental information is “identical” or “different”. For example, it may be determined whether or not there is a "significant difference" between the incidental information, and the display mode may be changed according to the determination. Specifically, the item in which the difference information is expressed by two values is determined to have the value “different” = “significant difference”. On the other hand, an item represented by a difference in value or a degree of coincidence of values is determined to have a “significant difference” only when the value exceeds a predetermined threshold. For items represented by difference in value, for example, in the case of the item of examination date, it is determined that "significant difference" exists when the difference in examination date is "five years" or more. Further, for items represented by the degree of coincidence of values, for example, it is determined that there is a “significant difference” when the degree of coincidence of slice thickness is less than “25%”. As a result, the user can recognize only important difference information by changing the display form of only items having a “significant difference” among items in which additional information has a difference. In another aspect, changing the display mode of an item having a "significant difference" is displaying a warning to the user. The information processing apparatus 100 may use another test method other than the above-described method to determine the “significant difference”.

  In addition, the display control unit 105 may change the display mode of each piece of difference information in accordance with the degree of the difference in the incidental information of each item. That is, the display control unit 105 may highlight the item having a large difference. Further, the importance of each item of incidental information is defined in advance, the importance of difference information of each item is acquired from the importance of the item and the degree of difference, and the display control unit 105 responds to the degree The display form of the difference information may be made different. In the calculation method of the importance of each difference information, for example, the importance of difference information can be defined by the product of the item importance and the degree of difference. As the display method of the difference information according to the importance, for example, the item to be displayed is emphasized more as the importance is higher (such as increasing the display density of the character string), and the item to be displayed is displayed as the importance is smaller. Display without emphasizing more (such as reducing the display density of text). The method of changing the display mode according to the degree of importance is not limited to this, and any method may be used as long as it is a method of changing the display mode according to the degree, such as changing color information according to the degree of importance. Good.

  According to the present embodiment, in addition to the difference between the images of the two medical images, by presenting the difference between the incidental information in association with each other, the user who is a doctor can support the evaluation of the difference image more appropriately. Can.

(Modification 1-1)
In the first embodiment, in step S2030, the difference image acquisition unit 103 generates a difference image between the first and second medical images. However, the method of acquiring the difference image is not limited to this. For example, the differential image between the first and second medical images is stored in advance in the data server 130 (previously generated by another device), and the differential image acquisition unit 103 uses the differential image as the data server 130. May be acquired from the

  Further, when the difference image has already been generated, the difference image acquisition unit 103 may obtain the generated difference image, and may generate the difference image only when it has not been generated. More specifically, when the difference image acquisition unit 103 generates a difference image using the first and second medical images once, the difference image may be stored in a storage unit (not shown) of the information processing apparatus 100 or a data server. Save on 130. Then, in step S2030, the difference image acquisition unit 103 inquires of the storage unit (not shown) of the information processing apparatus 100 or the data server 130 whether or not there is a difference image between the first and second medical images. If it exists, the stored difference image is acquired. On the other hand, if the image does not exist, the differential image acquisition unit 103 requests the image processing server 140 to perform processing of differential image generation.

  Here, the determination as to whether or not there is a difference image is realized as follows. That is, a storage unit (not shown) of the information processing apparatus 100 or the data server 130 holds a list of identification information (for example, series ID) of a pair of medical images as a source of a generated difference image. Then, by searching the inside of the list using the identification information of the medical image pair at the time of inquiry as a key, it can be determined whether or not there is a corresponding difference image. Thereafter, in step S2040, as in the first embodiment, difference information between incidental information of medical images is generated, and in step S2050, the generated difference information is associated with the stored difference image acquired in step S2030. Display. This makes it possible to reduce the cost of generating the difference image unnecessarily while obtaining the same effect as that of the first embodiment.

Second Embodiment
The information processing system according to the second embodiment records and stores incidental information of a difference image based on incidental information of two medical images. As a result, when the generated difference image is displayed, necessary information can be acquired or displayed in association with the difference image.

  FIG. 6 is a diagram showing the configuration of the information processing system according to the present embodiment. As the components, the first embodiment is the same except that the representative image determination unit 601 and the incidental information generation unit 602 are newly added to the information processing apparatus 600 corresponding to the information processing apparatus 100 of the first embodiment. It is the same as the form. Further, an output from the instruction acquisition unit 101 to the difference image acquisition unit 103 and an output from the difference image acquisition unit 103 to the medical image acquisition unit 102 are newly added. Further, in response to this, the operations of the respective units of the information processing apparatus 600 are partially different. Hereinafter, only differences from the first embodiment will be described.

  The representative image determination unit 601 determines one of the first and second medical images as a representative image. The incidental information generation unit 602 generates incidental information of a difference image between the first and second medical images.

  FIG. 7 is a flowchart showing the overall processing procedure performed by the information processing apparatus 600. However, in FIG. 7, the processes of steps S7050 and S7060 are the same as the processes of steps S2030 and S2040 in the flowchart of FIG. Hereinafter, only differences from the flowchart of FIG. 2 will be described.

(S7010) (obtain an instruction for image selection)
In step S7010, the instruction acquisition unit 101 acquires an instruction for image selection by the user from the instruction unit 150. Here, as in step S2010 of FIG. 2, an instruction to select the first and second medical images that are the basis of the difference image is acquired from the examination list displayed on the display unit 160. Also, if there is a generated difference image, an instruction to select the difference image displayed on the examination list is acquired.

  FIG. 8 is a view showing an example of a display for selecting an image on the examination list. Similar to 301 in FIG. 3, reference numeral 801 denotes an examination list in which medical images of a specific patient are listed. In the second embodiment, in addition to the medical image, the generated differential image is displayed in the examination list. On the examination list, the difference image is displayed in association with a representative image representing the first and second medical images from which the difference image is generated.

  In the example of FIG. 8, the differential image 802 is displayed side by side with a CT medical image 803 (examination date: 2017/03/02), which is a representative image representing two medical images that are generation sources of the differential image 802. This association is realized by holding the incidental information of the representative image determined by the representative image determining unit 601 in the incidental information of the difference image generated by the incidental information generation unit 602 in the processing of steps S7070 and S7080 described later. doing. Thereby, the user can recognize to which examination on the examination list the difference image belongs. In FIG. 8, 802 indicates a case where the user selects a difference image on the examination list. At this time, in order to make it clear that the image has been selected, the character string 802 is highlighted.

(S7020) (Select image)
In step S7020, the instruction acquisition unit 101 determines whether the instruction acquired in step S7010 is an instruction for medical image selection or an instruction for differential image selection. Then, when it is a medical image selection instruction, the image selection instruction information is output to the medical image acquisition unit 102. Then, the process proceeds to step S7030. On the other hand, when the acquired instruction is an instruction for selecting a difference image, the instruction information for image selection is output to the difference image acquisition unit 103. Then, the process proceeds to step S7110.

(S7030) (acquire medical image)
In step S7030, the medical image acquisition unit 102 performs the same process as step S2020 in the first embodiment. Furthermore, in the present embodiment, the acquired first and second medical images are also output to the representative image determination unit 601.

(S7040) (judged whether a difference image has not been generated)
In step S7040, the difference image acquisition unit 103 determines whether or not the difference image between the acquired first and second medical images is not generated, and if it is not generated, the process proceeds to step S7050. Move. On the other hand, if a difference image has been generated, the generated difference image is specified, and the process moves to step S7130. At this time, the determination as to whether or not the difference image is not generated can be performed by the method described in the modification 1-1 of the first embodiment. Alternatively, the feature of the process of step S7080 described later can be used.

  In step S7080, the incidental information of the original two medical images of the difference image is held in the incidental information of the difference image, and the difference image is stored in the storage unit (not shown) or the data server 130. Therefore, using the identification information of the first and second medical images acquired in this step as a key, the identification information of the pair of two medical images described in the incidental information of a large number of stored generated difference images Search for. This makes it possible to determine whether or not there is a difference image of those medical images, and to specify the difference image when it has been generated. By this method, compared with the method of the modified example 1-1 of the first embodiment, the storage unit (not shown) of the information processing apparatus 600 or the data server 130 of the two medical images which are the sources of the generated difference image. It is not necessary to save the list of pairs of information.

(S7050) (acquire a difference image)
In step S7050, the difference image acquisition unit 103 performs the same processing as step S2030 in the first embodiment. Furthermore, in the present embodiment, the acquired difference image is also output to the incidental information generation unit 602.

(S7060) (Generation of difference information between incidental information of medical image)
In step S7060, the difference information generation unit 104 performs the same processing as step S2040 in the first embodiment, and generates difference information indicating the difference between the incidental information of the first and second medical images.

(S 7070) (determine representative image)
In step S7070, the representative image determination unit 601 determines one of the acquired first and second medical images as representative images of two medical images to be associated with the difference image based on a predetermined reference. On the other hand, the medical image which is not the representative image is determined as the non-representative image. Then, the information on the determined representative image is output to the incidental information generation unit 602.

  As a determination criterion of the representative image, for example, referring to the incidental information of the first and second medical images, the newer one of the imaging date and time is determined as the representative image. In the interpretation of a medical image by a doctor who is a user, when the image of the newer one (current image) is to be interpreted and the past image of the same subject is to be compared, two medical images to be associated with the difference image. It is preferable as a representative image. In another embodiment, one of the first and second medical images having an older imaging date and time may be determined as a representative image.

  Further, it is also possible to determine an image (reference image) as a reference of alignment at the time of generating the difference image as a representative image. As described in the description of the image processing server 140, the differential image is aligned after aligning the comparison image (first medical image) towards the fixed reference image (second medical image) It is the image which acquired the difference value between an image and a reference | standard image. Therefore, the anatomical structure of the subject depicted on the image corresponds at each position between the difference image and the reference image. On the other hand, the anatomical structure of the subject may not correspond at each position between the comparison image and the difference image. In this case, since the difference image corresponds to the reference image, it is preferable to use the reference image as a representative image. In another embodiment, of the first and second medical images, a medical image which is a comparison image may be determined as a representative image.

  When a plurality of criteria are provided as described above, it is conceivable that medical images to be representative images differ depending on the criteria to be applied. For example, in step S7010, when the image with the older shooting date and time is selected as the reference image (the newer one is the comparison image), the comparison image becomes the representative image in the determination criteria for determining the newer shooting date and time as the representative image. It is determined. On the other hand, in the determination criterion for determining the representative image to be the reference for alignment, the reference image is determined to be the representative image. Therefore, in an example of the embodiment, any standard may be defined in advance as a basic setting (for example, a standard in which the newer one is a representative image), and the setting applied by the user may be changeable as needed.

  As described above, by automatically determining representative images representing two medical images that are the sources of difference images based on a predetermined standard, it is possible to appropriately determine which medical image the difference image belongs to. It can be clarified in the state. The user may select a representative image through the instruction unit 150. For example, two icons of a first medical image and a second medical image are displayed on display unit 160, and the user selects a representative image by selecting one of the displayed icons. It is possible to determine the non-representative image if not.

(S7080) (Generate additional information of difference image)
In step S7080, the incidental information generation unit 602 generates incidental information on the difference image based on the difference information and the information on the representative image, and records the incidental information on the acquired difference image. Then, the incidental information generation unit 602 stores the generated difference image holding the incidental information in a storage unit (not shown), and outputs the difference image to the display control unit 105. The data server 130 may be the destination to save the difference image.

  FIG. 9 is a diagram for explaining an example of the item of incidental information of the difference image and the attribute of the described content. In FIG. 9, reference numeral 901 denotes an item name of incidental information of the difference image, which is the same as the item name of incidental information of a normal medical image. The information processing apparatus 600 is matrix-like data in which contents of four categories of basic information of difference images, additional information of reference images and comparison images, and difference information are described in a storage unit or data server 130 (not shown). Information in a holding format may be generated and held. As described later, when a file holding information on a difference image is treated as a DICOM tag, the information may be read out from the DICOM tag to generate and hold data on the matrix shown in FIG. It may be read each time from the DICOM tag.

  Reference numeral 902 denotes basic information of incidental information of the difference image, which corresponds to incidental information of a normal medical image. The “representative image” and the “difference image” in 902 are information to be handed over from the incidental information of the representative image (the value of the first predetermined item) and information to be newly generated regarding the difference image (the second predetermined information). Item value).

  In the basic information 902, for example, items such as patient ID and patient name are not information held by the image data of the difference image itself, so items described in items such as patient ID and patient name of representative image that is the source of difference image Make it the same as the content. Further, the item of the examination ID is also made identical to the content described in the item of the examination ID of the representative image. Thereby, as shown in step S7010, when displaying the examination list, it is possible to display the difference image together with the representative image as a medical image having the same examination ID.

  Further, since the series ID is identification information of image data, and the difference image is an image different from the two medical images, the difference image is newly issued for the difference image. In addition, items such as the number of slices, slice thickness, image size (horizontal width), image size (vertical width), and pixel spacing are information held by the image data of the difference image, and thus can be obtained from the image data of the difference image. Information is described. In addition, an item such as a reconstruction function or the like in which information specific to image capture is described does not have a difference image, and is therefore blank. If the reconstruction function is the same between the two medical images that are the sources of the difference image, the name of the reconstruction function may be described without leaving such items blank. Also, even when the reconstruction function is different between the two, it may be described as "function yyy-function xxx". Thus, according to the item name (type of item) of the basic information, the item (first predetermined item) which should share the information of the representative image which is the source of the difference image records the information, while The item (second predetermined item) specific to the difference image records newly generated information.

  Further, the examination site can be read as the site of the subject depicted in the generated difference image. Accordingly, since the area of the difference image is a common area of the two medical images, the part information of the common area of the examination part of the reference image information and the comparison image information is described in the item of the examination part of the basic information of the difference image. For example, if the content described in the item of the examination part of the reference image is "Trunk (body trunk)" and the content described in the item of the examination part of the comparison image is "CHEST (chest)", the trunk is Wider range than chest, including chest. Therefore, since the common region is the chest, "CHEST (chest)" is described in the examination region of the difference image. It is possible to match a common area with a narrow area by defining in advance a site having a narrow range in advance when the examination site extends over a wide area of the body. .

  For example, the constituent parts of "Trunk" are defined as follows. "CHEST", "Breast", "Heart", "Stomack", "Liver", "ABDOMEN", "BACK", "Shoulder" ), “Femoral region (thigh)”. Thereby, the common area of "Trunk" and "CHEST" can be determined as "CHEST". In addition, when a character string representing a common area can not be easily identified from a character string representing an examination site, at least one of two medical images is subjected to image processing by a known image processing technology and rendered in the common area. By specifying the region, it is also possible to obtain the inspection region of the difference image. For example, segmentation processing using a probability atlas or the like is performed on an image having a wide imaging region of two medical images, and each region (brain, lung field, liver, heart, stomach, large intestine, spine) in the image , Pelvis, etc.). And the test part of a difference image can be calculated by specifying the part contained in the common field between medical images among those parts.

  Reference numerals 903 and 904 respectively indicate values of corresponding items in the reference image and the comparison image. The “reference image” described in 903 of FIG. 9 indicates information incidental to the reference image in each item. The “comparison image” described in 904 of FIG. 9 indicates the information attached to the comparison image in each item. Reference numeral 905 denotes difference information between incidental information of the first and second medical images. The difference information 905 is the difference information generated in step S7060. Here, it is expressed as group A (for example, an item which can not be expressed numerically): binary, group B (for example an item where difference information is expressed as a numerical value): degree of matching of values.

  FIG. 10 is a specific example of incidental information of a difference image. FIG. 10A shows an example of incidental information having a matrix-like data structure shown in FIG.

  In FIG. 10A, reference numerals 1001, 1002, 1003, 1004, and 1005 are information corresponding to 901, 902, 903, 904, and 905 in FIG. 9, respectively. In the items 1002, 1003, 1004, and 1005, specific contents based on the attributes described in FIG. 9 are described. For example, the attribute of the item of the examination ID of the basic information 902 in FIG. 9 is “representative image”. Here, when the determination criterion of the representative image which is “representative image = reference image” is adopted in step S7070, the inspection ID of the reference image information 1003 is included in the item of the inspection ID of the basic information 1002 as shown in FIG. The same examination ID as "0002" is stored. The same applies to the other items. As shown in FIG. 10, the information processing apparatus can easily acquire the incidental information of the reference image and the comparison image which is the source of the difference image by only acquiring the difference image by holding the incidental information of the difference image, and Information of those representative images can also be acquired. Furthermore, the difference information between the incidental information of the reference image and the comparison image can be easily acquired.

  The incidental information of the difference image may be expressed in DICOM format. When expressed in the DICOM format, each is described in a data element including a predefined tag (for example, (0010, 0020) for patient ID) and its data. FIG. 10B is a view for explaining incidental information of a differential image expressed in the DICOM format. Information 1001 and 1002 are information corresponding to 901 and 902 in FIG. 9, respectively. A pair of a tag corresponding to 1001 and data of 1002 is described in each data element. In one aspect of the embodiment, as shown in FIG. 10B, the incidental information of the difference image may not include incidental information of the reference image and the comparison image. In the example shown in FIG. 10B, information for specifying a comparison image and information for specifying a representative image (here, a reference image) are included. An apparatus that handles the incidental information in the DICOM format can obtain information of the comparison image and the reference image based on the information. Also, in the example shown in FIG. 10B, it includes data elements related to the image type indicating that the image included in the DICOM file is a difference image.

  The difference information 1005 illustrated in FIG. 10A may be included in the incidental information of the difference image as a data element including each tag and data of the DICOM format. Thereby, the difference information can be displayed on any viewer that handles the file including the incidental information in the DICOM format.

  The tag in the data in DICOM format may be a standard tag in which the content and format of the stored information are predefined, or may be a private tag in which the content and format of the stored information can be uniquely defined. The matrix data shown in FIG. 10A may be attached to the difference image as a data element having a standard tag or a private tag. Each data included in the matrix shown in FIG. 10A may be attached to the difference image as a data element having a standard tag or a private tag.

Although the incidental information of the difference image holds all incidental information of the reference image and the comparison image in the example shown in FIG. 10A, the information holding method is not limited to this. For example, as shown in FIG. 10B, the information of the reference image and the comparison image held by the supplementary information of the difference image is only the series ID which is the identification information, and the series ID is used as a key when necessary. The corresponding reference image or comparison image may be retrieved to access the incidental information thereof. Further, since the examination date, imaging date, modality, and device maker information of the basic information 902 are not information belonging to the image data of the difference image itself, the incidental information of the representative image is applied. However, regarding these items, by replacing the examination date and imaging date with the image creation date, the modality with the image type, and the device maker with the image creation maker, specific information belonging to the image data of the difference image can be applied as follows. . For example,
・ Examination date and imaging date (image creation date): 2017/03/03 (difference image creation date)
Modality (image type): Subtraction (difference image)
・ Device maker (image creation maker): Company C (maker who created difference image)
Etc. In addition to the basic information 902 described as a standard tag of DICOM, information specific to these difference images is additionally described by adding a private tag of DICOM (image creation date, image type, image creation maker). You may do so.

(S7090) (The difference information is displayed in association with the difference image)
In step S7090, the display control unit 105 causes the display unit 160 to display the first and second medical images acquired from the medical image acquisition unit 102. Further, the display control unit 105 causes the display unit 160 to display the difference information acquired from the difference information generation unit 104 in association with the difference image acquired from the difference image acquisition unit 103. A specific example in which the display control unit 105 causes the difference information to be displayed in association with the difference image is the same as that in the first embodiment.

(S7110) (acquire generated difference image)
In step S7110, the difference image acquisition unit 103 acquires the generated difference image stored in the storage unit (not shown) or the data server 130 based on the instruction for selecting the difference image acquired in step S7010. Then, the difference image acquisition unit 103 outputs the acquired difference image to the medical image acquisition unit 102 and the display control unit 105.

(S7120) (A medical image is acquired based on incidental information)
In step S7120, the medical image acquisition unit 102 specifies two medical images as a generation source based on the additional information of the acquired difference image, and acquires the two specified medical images from the data server 130. Then, the medical image acquisition unit 102 outputs the acquired two medical images to the display control unit 105. In the process of step S7080, it is assumed that incidental information of the reference image which is the generation source of the differential image and the comparison image is held in the incidental information of the differential image. Therefore, two medical images can be specified and acquired by accessing the reference image described in the incidental information of the difference image and the incidental information of the comparison image. Specifically, the series ID (identification information) of each of the reference image information 1003 and the comparison image information 1004 of FIG. 10A described in the supplementary information of the difference image is acquired. Alternatively, the information for identifying the comparison image in FIG. 10B and the information for identifying the representative image (reference image) are acquired. Then, the medical image is acquired from the data server 130 using the two acquired series IDs as a key. As described above, by adding the incidental information of the two medical images to the incidental information of the difference image, if the difference image is acquired, it is possible to simultaneously acquire the original medical image.

  In order to make it easy to understand on the examination list in FIG. 8 that two medical images have been specified in step S7120, the character string of the specified medical image may be highlighted. For example, in addition to the CT medical image 803 (representative image = reference image) on the examination date: 2017/03/02 to which the difference image belongs, the CT medical image on the examination date: 2014/10/25 as a non-representative image (= comparison image) If 804 is identified, it will be highlighted as follows. That is, the character strings 803 and 804 are highlighted. As a result, when the user selects the difference image 802, the user can easily recognize the two medical images from which they are generated.

(S7130) (acquire generated difference image)
In step S7130, the difference image acquisition unit 103 acquires the generated difference image identified in step S7040. The acquisition method is the same as in step S7110, and thus the description thereof is omitted. Then, the difference image acquisition unit 103 outputs the acquired generated difference image to the display control unit 105. Thereby, when the difference image has already been generated, it is possible to reduce the cost of generating the difference image unnecessarily.

  The process of the information processing device 600 is performed as described above. As described above, when displaying the generated difference image once, if the user selects the first and second medical images in step S7010, the process proceeds from step S7020 to step S7030. Furthermore, the process proceeds from step S7040 to step S7130, and after the generated difference image is acquired, the difference information recorded in the supplementary information of the difference image is read in step S7090, and is displayed in association with the difference image. On the other hand, when the user selects a difference image in step S7010, the process moves from step S7020 to step S7110, and after the generated difference image is acquired, the same display is performed in step S7090. Therefore, when displaying the generated difference image, the cost of generating the difference information in step S7060 can be reduced.

  According to the second embodiment, the incidental information of the difference image is recorded and stored based on the incidental information of the two medical images. For example, although the examination ID in the supplementary information of the difference image takes over the examination ID of the reference image which is the representative image, the series ID is newly issued as information unique to the difference image. As a result, when the generated difference image is displayed, necessary information can be obtained, or the difference image and the representative image can be associated and displayed.

  Furthermore, according to the second embodiment, it is possible to record and save difference information between incidental information of two medical images as incidental information of a difference image in incidental information. Thus, when the difference image is displayed again, the difference information recorded in the supplementary information of the difference image is read, and can be displayed in association with the difference image. Therefore, it is possible to reduce the cost of generating difference information unnecessarily each time the generated difference image is displayed.

<Modification of Second Embodiment>
FIG. 15 is a view showing an example of a screen when a DICOM file including a difference image generated by the information processing apparatus 600 and incidental information is read by a viewer (not shown).

  An area 1501 indicates information on the selected patient and the examination. An area 1502 displays a series included in an examination indicated by one examination ID. The example shown in FIG. 15 shows a state in which the difference image 1503 before 2 years, 4 months, and 5 days ago is selected. An area 1504 displays a medical image, and in the example of FIG. 15, a difference image 1503 is displayed. An area 1505 displays additional information of the selected series.

  Since the difference image takes over the examination ID of the representative image and a new series ID is issued, a list of difference images having the same representative image can be displayed in a scene where the medical image is selected by the examination ID. it can. In the example shown in FIG. 15, it is easy to select one of two series of difference images of the CT image and the past image acquired as the reference image (representative image) displayed in the area 1502. , Can display an image. As a result, a doctor who views a medical image can easily select a necessary medical image and display it on a viewer (not shown).

Third Embodiment
In the third embodiment, the information processing apparatus automatically acquires and displays the reliability according to the number of items of difference occurrence in the difference information and the degree of the difference. This allows the user to confirm the quantitative quality of the difference image, which can be useful for interpretation using the difference image.

  FIG. 11 is a diagram showing the configuration of the information processing system according to the third embodiment. The information processing apparatus 100 is the same as the information processing apparatus 100 according to the first embodiment except that a reliability acquisition unit 1101 is newly added. Hereinafter, only differences from the first embodiment will be described.

  The reliability acquisition unit 1101 acquires the reliability of the difference image based on the difference information between the incidental information of the two medical images which are the sources of the difference image.

  FIG. 12 is a flowchart showing the overall processing procedure performed by the information processing apparatus 1100. However, in FIG. 12, steps S11010, S11020, S11030, and S11040 are the same as the processes of the following steps in the flowchart of FIG. That is, the processing is the same as the processing in steps S2010, S2020, S2030, and S2040. Therefore, the description of the same processing is omitted. Hereinafter, only differences from the flowchart of FIG. 2 will be described.

(S11050) (Accuracy of difference image obtained based on difference information)
In step S11050, the reliability acquisition unit 1101 acquires the reliability of the difference image based on the acquired difference information. Then, the acquired reliability is output to the display control unit 105. That is, it corresponds to an example of an acquisition unit that acquires the reliability of the difference image based on the difference information. The specific method of obtaining the reliability will be described below. In the present embodiment, the degree of reliability is acquired according to the number of items in which a difference occurs between incidental information and the degree thereof. More specifically, the reliability S is acquired using the following formula.

Here, i represents the item number of the difference information, and N represents the number of items of the difference information (1 ≦ i ≦ N). Here, as in the relation between the patient ID and the patient name, one of the items representing essentially the same information is regarded as the item to be calculated in equation (3), and the other is not included in the item to be calculated. And w _i represents the weight of the i-th item of difference information (w _i 00). The value of w _{i is} a value determined in advance for each item number i, and the value of the weight is larger as the degree to which the difference information affects the quality of the difference image is larger, and the value is smaller as the degree is smaller. It is set. That is, it corresponds to an example of an acquisition unit that acquires the reliability of the difference image based on the number of items having a difference included in the difference information and the degree of the difference for each item. Furthermore, the method corresponds to an example of an acquisition unit that acquires the reliability of the difference image based on the weight set for each item.

For example, if the patient ID (patient name) is different, the two medical images that are the basis of the difference image are images obtained by imaging different patients, so the anatomical structures shown in the images are significantly different. Therefore, the effect of this item difference on the quality of the difference image is significant. In addition, since the nature of the information captured in the medical image is completely different if the modality item is different, the influence on the quality is serious. Therefore, for such items, the weight w _i is set to a large value (eg w _i = 10). On the other hand, when the apparatus manufacturer is different, although the fine characteristics of the image are different depending on the maker, since the main image characteristics are the same when the modality is the same, the image does not largely change greatly. Therefore, the impact on quality is moderate. Therefore, for such items, the weight w _{i is set} to medium (eg, w _i = 5). In addition, w _i = 0 is set for an item in which the difference information does not affect the quality of the difference image at all.

M _i is the degree of coincidence (0 ≦ M _i ≦ 1) between incidental information in the i-th item of difference information. As shown in step S 2040 in the first embodiment, the difference information is expressed by (A) a binary value, (B) a value difference, or (C) a value expressed by a coincidence of three values. It is classified into types. As for (A), since the difference information can only indicate whether the value of the incidental information is “identical” or “different”, the degree of coincidence M _i = 1 (identical) or 0 (different) is represented. For example, M _i = 1 if the difference information of the modality item is “identical”, and M _i = 0 if “different”. As for (C), the degree of coincidence M of the values acquired in step S 2040 in the first embodiment is adopted as the degree of coincidence M _i for each item as it is. As for (B), since the difference information is the difference between the item values, it does not fit between 0 and 1 as it is. For example, in the case where the difference information of the item on the examination date is "two years and four months and five days", "two years and four months and five days" = "859" days, which exceeds the value 1. Therefore, the following formula is applied.

Here, D _i represents the difference between item values, and C is a constant. Here, for example, C = 365 is applied. For example, if the difference information of the inspection date is 0 days (same) (Di = 0) is _M i = 1.0, and the larger the difference information (Di) is the examination date, the value of Mi is only 0 It is approaching without. Further, in the case where the difference information of the examination date is exactly 1 year = 365 days (Di = 365), Mi = 0.5. In the case of the above-described example, D _i = 859, and the result of equation (4) becomes M _i = 0.29. As described above, the reliability acquisition unit 1101 acquires the reliability S of the difference image.

(S11060) (Relationship display with difference image and reliability)
In step S11060, the display control unit 105 causes the display unit 160 to display the first and second medical images acquired from the medical image acquisition unit 102. Further, the display control unit 105 causes the display unit 160 to display the information of the reliability S acquired from the reliability acquisition unit 1101 in association with the difference image acquired from the difference image acquisition unit 103. At this time, since the display method of the two medical images and the difference image is the same as that of step S2050 of the first embodiment, the description will be omitted. Further, in the present embodiment, the display control unit 105 associates the reliability S with the difference image, and displays the same within or near the cross-sectional image 503 of the difference image of FIG. 5, for example.

  FIG. 13 is a view showing an example of the association display of the reliability to the difference image. 1301 in FIG. 13 represents the reliability of the difference image, and the other display items represent the same as in FIG. In this example, 1301 is displayed inside the difference image. Thereby, the user can easily confirm the reliability of the difference image under observation. Note that the difference information 512 and the difference information list 504 on the cross-sectional image 503 displayed in the first embodiment may or may not be displayed. Alternatively, only one of them may be displayed (e.g., the difference information 512 is displayed and the difference information list 504 is not displayed). The processing of the information processing apparatus 1100 is performed as described above.

  According to the third embodiment, the user confirms the quantitative quality of the difference image by automatically acquiring and displaying the reliability according to the number of items of difference occurrence in the difference information and the degree of the difference. It can be used for image interpretation using difference images.

<Other Modifications>
Note that each embodiment includes one that directly or remotely supplies a program of software that implements the functions of each of the above-described embodiments to a system or an apparatus. In addition, the embodiments are also included in the embodiments where the computer of the system or apparatus reads out and executes the supplied program code.

  Therefore, the program code itself, which is installed in the computer in order to realize (make executable) the functional processing of each embodiment, realizes each embodiment. That is, each embodiment includes the computer program itself for realizing the functional processing of each embodiment.

  In that case, as long as it has the function of a program, it may be in the form of an object code, a program executed by an interpreter, script data supplied to an OS, or the like.

  Examples of recording media for supplying the program include a flexible disk, a hard disk, an optical disk, a magneto-optical disk, an MO, a CD-ROM, a CD-R, and a CD-RW. There are also magnetic tapes, non-volatile memory cards, ROMs, DVDs (DVD-ROMs, DVD-Rs) and the like.

  In addition, as a program supply method, a browser on a client computer is used to connect to an Internet home page. Then, the program can be supplied from the home page by downloading the computer program itself of each embodiment or a compressed file including an automatic installation function to a recording medium such as a hard disk.

  The present invention can also be realized by dividing the program code constituting the program of each embodiment into a plurality of files and downloading the respective files from different home pages. That is, each embodiment includes a WWW server which causes a plurality of users to download program files for realizing the functional processing of each embodiment by a computer.

  In addition, the program of each embodiment is encrypted, stored in a storage medium such as a CD-ROM, and distributed to users, and the user who clears the predetermined conditions has key information for deciphering encryption from a home page via the Internet. Make it download. Then, it is possible to execute the program encrypted by using the downloaded key information and install it on a computer.

  Also, the functions of the above-described embodiments are realized by the computer executing the read program. In addition, based on the instructions of the program, an OS or the like running on the computer performs part or all of the actual processing, and the functions of the above-described embodiments can be realized also by the processing.

  Furthermore, the program read from the recording medium is written to a memory provided in a function expansion board inserted in the computer or a function expansion unit connected to the computer. Thereafter, based on the instruction of the program, a CPU or the like provided in the function expansion board or the function expansion unit performs part or all of the actual processing, and the functions of the above-described embodiments are also realized by the processing.

  In addition, each Example mentioned above only shows the example of embodiment in the case of implementing each Example, and the technical scope of each Example should not be limitedly interpreted by these. . That is, the mechanism of the present disclosure can be implemented in various forms without departing from the technical concept or its main features.

Claims (16)

The first incidental information which is information incidental to the first medical image and the second incidental information which is incidental to the second medical image acquired in the examination different from the first medical image A first acquisition unit to acquire;
Third incidental information as information incidental to a difference image generated using the first medical image and the second medical image based on the first incidental information and the second incidental information Second acquisition means for generating information;
An output unit that associates the third incidental information with the difference image and outputs the output information;
An information processing apparatus comprising:   The second acquisition unit is configured, as a value of a first predetermined item in the third incidental information, of the first predetermined item in any of the first incidental information and the second incidental information. The information processing apparatus according to claim 1, wherein the third incidental information is generated by recording a value. The information processing apparatus further comprises determination means for determining any one of the first medical image and the second medical image as a representative image,
3. The apparatus according to claim 2, wherein the second acquisition unit records the value of the item in the incidental information of the representative image as the value of the first predetermined item in the third incidental information. Information processing equipment.   The information processing apparatus according to claim 3, wherein the first predetermined item is an item of information for identifying an examination.   The said determination means determines the image whose imaging | photography date / time is newer among the said 1st medical image and the said 2nd medical image to the said representative image, The said 1st medical image characterized by the above-mentioned. The information processing apparatus according to claim 1. The difference image is generated by aligning the comparison image with the reference image, using one of the first medical image and the second medical image as a reference image and the other as a comparison image. Yes,
The information processing apparatus according to claim 3, wherein the determination unit determines the reference image as the representative image.   The second acquisition means generates the third incidental information by recording a newly generated value as a value of a second predetermined item in the third incidental information. An information processing apparatus according to any one of claims 1 to 5.   8. The information processing apparatus according to claim 7, wherein the second predetermined item is an item of information for identifying the difference image. The second acquisition means identifies information for identifying an examination, which is included in incidental information of either the first incidental information or the second incidental information, with an inspection in the third incidental information. And information to
The information processing apparatus according to claim 1, wherein information for identifying the difference image is newly generated, and is used as information for identifying an image in the third incidental information.   The information processing apparatus according to claim 9, wherein the information for identifying the examination is an examination ID, and the information for identifying the image is a series ID. A first medical image registered to a second medical image acquired in an examination different from the first medical image, and a difference image which is a difference between the second medical image and the second medical image;
A data element comprising information identifying an examination of either the first medical image or the second medical image;
A data element having information for identifying the difference image;
A data structure that contains The first incidental information which is information incidental to the first medical image and the second incidental information which is incidental to the second medical image acquired in the examination different from the first medical image A first acquisition unit to acquire;
Third incidental information as information incidental to a difference image generated using the first medical image and the second medical image based on the first incidental information and the second incidental information Second acquisition means for generating information;
An output unit that associates the third incidental information with the difference image and outputs the output information;
An information processing system comprising: The first incidental information which is information incidental to the first medical image and the second incidental information which is incidental to the second medical image acquired in the examination different from the first medical image The process to acquire,
Third incidental information as information incidental to a difference image generated using the first medical image and the second medical image based on the first incidental information and the second incidental information Generating information;
Outputting the third incidental information in association with the difference image;
An information processing method comprising: The first incidental information which is information incidental to the first medical image and the second incidental information which is incidental to the second medical image acquired in the examination different from the first medical image A first acquisition unit to acquire;
Third incidental information as information incidental to a difference image generated using the first medical image and the second medical image based on the first incidental information and the second incidental information Second acquisition means for generating information;
Third acquisition means for acquiring a third medical image in which the third incidental information and the difference image are associated;
Display control means for arranging and displaying the difference image and information on at least one of the first medical image and the second medical image based on the third incidental information;
An information processing system comprising: Image acquisition means for acquiring a plurality of medical images acquired in different examinations;
A difference image acquisition unit that acquires a difference image generated using the plurality of medical images;
An information acquisition unit that acquires a plurality of incidental information corresponding to each of the plurality of medical images;
Generating means for generating additional information of the difference image based on the plurality of additional information according to the items, the additional information comprising at least one item;
An output unit that associates and outputs the difference image and incidental information of the difference image;
An information processing apparatus comprising: A program for causing a computer to execute the information processing method according to claim 13.