JPWO2008142915A1 - Medical image management apparatus and program - Google Patents

Abstract

Reduce the amount of medical image data. The image server 30 receives from the modality 10 a DICOM file including image data of a medical image and incidental information related to the image data. The received DICOM file is an image data file (general-purpose image file) and incidental information file (DICOM). Header file) and store them in the storage unit in association with each other. The image server 30 compresses the general-purpose image file based on a compression condition that is determined in advance according to the storage period of the general-purpose image file. As the compression condition, the compression rate is set higher as the storage period of the general-purpose image file is longer.

Description

  The present invention relates to a medical image management apparatus and a program.

  In recent years, computerization of information has been attempted in many medical institutions. For example, an image generation apparatus (modality) such as a CR (Computed Radiography) apparatus, a CT (Computed Tomography) apparatus, or an MRI (Magnetic Resonance Imaging) apparatus may use DICOM (Digital Imaging and Communications in Medicine) on image data obtained by imaging. A DICOM file with accompanying information according to the standard is generated. The image server stores and manages the DICOM file, and provides it when a DICOM file request is received from a DICOM-compatible image viewer terminal. The image viewer terminal displays a medical image on a high-definition monitor based on the DICOM file.

  In addition, there are cases where it is desired to refer to an image for explanation or diagnosis of a patient even in an electronic medical record terminal used when creating an electronic medical record or viewing a medical examination result. Electronic medical record terminals generally do not have a function for directly processing a DICOM file, an advanced image processing function, or the like. Therefore, in the image server, a general-purpose image file in which only the image data in the DICOM file is converted into a format such as JPEG (Joint Photographic Experts Group) or PDF (Portable Document Format) in advance is generated, and the Web server function Is provided, a general-purpose image file is provided in response to a request from an electronic medical record terminal.

For example, in a wide area hospital information system that can share medical information throughout the region, SGML (Standard Generalized Markup Language) / HTML (HyperText Markup) records on the IC card include link information for referencing external file groups. A technique described in (Language) has been proposed (see Patent Document 1).
JP-A-10-79770

  However, in the image server, in addition to the DICOM file, when saving a general-purpose image file that can respond to a request from an electronic medical record terminal or the like, a plurality of files for the same medical image are held, increasing the storage capacity. Was invited. In addition, since a general-purpose image file is generated regardless of whether there is a reference from an electronic medical record terminal or the like, the processing for generating the general-purpose image file is wasted when it is not referenced.

  Also, medical images require different image quality depending on the purpose of use. For example, when an image interpretation doctor performs image diagnosis, the purpose is to find abnormalities such as lesions in the image, and therefore there should be no deterioration in image quality. In addition, the reference doctor who makes a diagnosis based on a report prepared by the interpreting doctor uses images when explaining to the patient, attaching it to the medical chart, and revisiting the patient. The image quality is not required, but a certain level or higher image quality is required. In addition, when an image is used for the education of a resident or the like, it is not used for diagnosis, and it is sufficient if the image quality is as required. Moreover, since the imaging engineer only wants to refer to the imaging conditions for re-imaging and does not need an image, the image quality does not matter. Therefore, it is not necessary to store the image file in an uncompressed state until a high-quality image is not required.

  The present invention has been made in view of the above-described problems in the prior art, and an object thereof is to reduce the data amount of medical images.

  In order to solve the above-described problem, the medical image management apparatus according to claim 1 includes a receiving unit that receives image data of medical images and supplementary information related to the image data, a storage unit, and the receiving unit. The DICOM file received by the method is divided into an image data file and an incidental information file, stored in the storage unit in association with each other, and the storage period after the image data file starts to be stored in the storage unit And a control means for compressing the image data file based on a predetermined compression condition.

  According to a second aspect of the present invention, in the medical image management apparatus according to the first aspect, the compression condition is set such that the compression rate is higher as the storage period of the image data file is longer.

  According to the third aspect of the present invention, the computer receives a DICOM file containing medical image image data and supplementary information related to the image data, a storage unit, and a DICOM file received by the receiving unit. Based on a compression condition determined in advance according to a storage period after the file of the image data is started to be stored in the storage unit. And a program for causing the image data file to function as control means for compressing the image data file.

  According to a fourth aspect of the present invention, in the program according to the third aspect, the compression condition is determined such that the compression rate is higher as the storage period of the image data file is longer.

  According to the first and third aspects of the present invention, by dividing the DICOM file into an image data file and an accompanying information file, only the image data file can be compressed, and the amount of medical image data is increased. Can be reduced.

  According to the second and fourth aspects of the invention, the longer the storage period of the image data file is, the higher the compression rate is. Therefore, the longer the storage period is, the more the data amount can be reduced.

1 is a system configuration diagram of a medical image system according to an embodiment of the present invention. It is a figure for demonstrating the division | segmentation of a DICOM file. It is a block diagram which shows the functional structure of an image server. It is a figure which shows the DICOM header file and general-purpose image file whose retention period is less than one year. It is a figure which shows the DICOM header file and general-purpose image file after a preservation | save period passes 1 year. It is a figure which shows the DICOM header file and general purpose image file after a preservation | save period passes 3 years. It is a flowchart which shows the process performed in an image server.

  Hereinafter, an embodiment of a medical image management apparatus according to the present invention will be described with reference to the drawings.

[System configuration of medical imaging system]
FIG. 1 shows a system configuration of the medical image system 100. As shown in FIG. 1, a medical image system 100 includes a modality 10, a RIS (Radiological Information System) 20, an image server 30, an image viewer terminal 40, and an electronic medical record terminal 50. Are connected to each other so that data communication is possible.

  The RIS 20 is configured by a computer having a control unit, a storage unit, an operation unit, a display unit, a communication unit, and the like, and performs information management such as medical appointment reservation, diagnosis result report, results management, and material inventory management in the radiology department. . The RIS 20 receives the registration of the inspection order by the operator, generates inspection order information based on the registered inspection order, and transmits it to the modality 10. The examination order information is data indicating the contents of the examination order for imaging and diagnosis. Further, the RIS 20 transmits an acquisition request for acquiring a DICOM header file to be described later to the image server 30.

  The modality 10 is an image generation device that images a patient and generates image data of a medical image. The modality 10 adds a supplementary information conforming to the DICOM standard to the image data of the taken medical image, generates a DICOM file, and transmits it to the image server 30. The DICOM file includes image data of medical images and incidental information related to the image data. The incidental information includes patient information, examination information, series information, and the like. Patient information is data set for each patient, such as the patient's name, patient ID, and sex. The examination information is data indicating examination conditions such as an examination ID for identifying an examination, an examination site, an imaging direction, and a body position. The series information is data including a series ID indicating the unit (series) of a series of medical images for each modality 10 generated in one examination and the type of the modality 10.

  The image server 30 is a medical image management apparatus that stores and manages image data of medical images and incidental information corresponding to the image data. The image server 30 receives the DICOM file from the modality 10. As shown in FIG. 2, the image server 30 divides the received DICOM file into an image data file (hereinafter referred to as a general-purpose image file) and an accompanying information file (hereinafter referred to as a DICOM header file). And save.

  In response to a file acquisition request received from another device, the image server 30 transmits a DICOM header file, a general-purpose image file, or a DICOM file obtained by combining these two files to the other device. Here, the acquisition request includes file specification information (patient information, examination information, series information, SOP instance UID, or a combination of these information) for specifying a file to be acquired.

  The image viewer terminal 40 is a device that displays a medical image and various information related to the medical image based on the DICOM file. The image viewer terminal 40 transmits an acquisition request for acquiring a DICOM file to the image server 30. A user such as an interpretation doctor performs interpretation on the image viewer terminal 40.

  The electronic medical record terminal 50 has an electronic medical record function for creating an electronic medical record, and displays a medical image based on a general-purpose image file for use in diagnosis of a reference doctor. The electronic medical record terminal 50 transmits an acquisition request for acquiring a general-purpose image file to the image server 30.

[Functional configuration of image server]
FIG. 3 shows a functional configuration of the image server 30. As shown in FIG. 3, the image server 30 includes a control unit 31, an operation unit 32, a display unit 33, a communication unit 34, a ROM (Read Only Memory) 35, a storage unit 36, a timing unit 37, and the like. 38 is connected.

  The control unit 31 includes a CPU (Central Processing Unit), a RAM (Random Access Memory), and the like, and comprehensively controls the processing operation of each unit of the image server 30. Specifically, the CPU reads various processing programs stored in the ROM 35 in accordance with an operation signal input from the operation unit 32 or an instruction signal received by the communication unit 34, and a work piece formed in the RAM. Expand to the area and perform various processes in cooperation with the program.

  The operation unit 32 includes a keyboard having cursor keys, numeric input keys, various function keys, and the like, and a pointing device such as a mouse. The operation unit 32 controls operation signals input by key operations or mouse operations on the keyboard. To 31.

  The display unit 33 is configured by an LCD (Liquid Crystal Display), and displays various screens based on display data input from the control unit 31.

  The communication unit 34 includes a LAN (Local Area Network) adapter, a router, a TA (Terminal Adapter), and the like. The modalities 10, the RIS 20, the image viewer terminal 40, the electronic medical record terminal 50, and the like connected via the communication network N Send and receive data to and from the device.

  The communication unit 34 employs a general-purpose Web communication protocol such as HTTP (HyperText Transfer Protocol) when transmitting a DICOM header file to the RIS 20 or a general-purpose image file to the electronic medical record terminal 50. The communication unit 34 adopts a DICOM compatible protocol when transmitting a DICOM file to the image viewer terminal 40 or receiving a DICOM file from the modality 10.

  The ROM 35 is configured by a nonvolatile semiconductor memory or the like, and stores a control program, parameters and files necessary for executing the program, and the like.

  The storage unit 36 is a storage device such as a hard disk, and stores data such as general-purpose image files and DICOM header files.

  The time measuring unit 37 is configured by an RTC (Real Time Clock), measures the current date and time, and outputs it to the control unit 31.

  When the communication unit 34 receives the DICOM file from the modality 10, the control unit 31 divides the DICOM file into a general-purpose image file and a DICOM header file as shown in FIG. Then, the control unit 31 stores the general-purpose image file and the DICOM header file in the storage unit 36 in association with each other. For example, the general-purpose image file and the DICOM header file are associated with each other by attaching the SOP instance UID included in the incidental information to the file name of the general-purpose image file. The general-purpose image file may have any image format such as bitmap, JPEG, JPEG2000, etc. However, in this embodiment, when the DICOM file is divided into the general-purpose image file and the DICOM header file, the bitmap is used. The general-purpose image file is saved in the format. In addition, when the general-purpose image file and the DICOM header file are stored in the storage unit 36, the control unit 31 acquires the current date and time from the time measuring unit 37 and attaches a time stamp to each file. The time stamp is information indicating the date and time when the storage is started, and is the start date and time when the storage period is calculated.

  In addition, the control unit 31 transmits a DICOM header file, a general-purpose image file, or a DICOM file to the other device via the communication unit 34 in response to a file acquisition request received from the other device via the communication unit 34. Specifically, when a DICOM header file acquisition request is received from the RIS 20 via the communication unit 34, the control unit 31 stores the DICOM header file specified by the file specification information included in the acquisition request in the storage unit 36. And the DICOM header file is transmitted to the RIS 20 via the communication unit 34. In addition, when receiving a general-purpose image file acquisition request from the electronic medical record terminal 50 via the communication unit 34, the control unit 31 stores the general-purpose image file specified by the file specification information included in the acquisition request in the storage unit 36. The general-purpose image file is transmitted to the electronic medical record terminal 50 via the communication unit 34. Further, when a DICOM file acquisition request is received from the image viewer terminal 40 via the communication unit 34, the control unit 31 is a general-purpose image file corresponding to the DICOM file specified by the file specification information included in the acquisition request. The DICOM header file is read from the storage unit 36, the two files are combined to generate a DICOM file, and the generated DICOM file is transmitted to the image viewer terminal 40 via the communication unit 34.

  In addition, the control unit 31 compresses the general-purpose image file based on a compression condition determined in advance according to the storage period of each general-purpose image file stored in the storage unit 36. As the compression condition, the compression rate is set higher as the storage period of the general-purpose image file is longer. That is, as the storage period elapses, the data amount of the general-purpose image file decreases. The compression rate here is the compression rate from the initial state, and does not indicate the compression rate from the previous stage in the case of performing compression in stages.

  Specifically, the control unit 31 acquires the current date and time from the time measuring unit 37, and the general-purpose image file is stored in the storage unit based on the acquired current date and time and the date and time of the time stamp attached to the general-purpose image file. In 36, the storage period from the start of storage is calculated. Then, when the storage period of the general-purpose image file has passed one year, the control unit 31 performs JPEG2000 reversible compression conversion on the general-purpose image file (bitmap image) to generate a JPEG2000 reversible compression image. Here, the compression rate when compressing from a bitmap image to a JPEG2000 lossless compressed image is approximately 1/3. FIG. 4A shows a DICOM header file and a general-purpose image file whose retention period is less than one year, and FIG. 4B shows a DICOM header file and a general-purpose image file after the storage period has passed one year. A JPEG 2000 lossless compressed image has an image size that is approximately 1/3 of a bitmap image. Since the original image (bitmap image) can be reproduced based on the JPEG2000 lossless compression image, the data amount of the general-purpose image file can be reduced while maintaining the image quality.

  In addition, when the storage period of the general-purpose image file has passed 3 years, the control unit 31 performs JPEG2000 irreversible compression conversion on the general-purpose image file to generate a JPEG2000 irreversible compressed image. Here, the compression rate when compressing from a bitmap image to a JPEG2000 lossy compressed image is approximately 1/20. FIG. 4C shows the DICOM header file and the general-purpose image file after the storage period has passed 3 years. A JPEG2000 lossy compressed image has an image size that is approximately 1/20 of a bitmap image.

[Operation of image server]
Next, the operation in the image server 30 will be described.
FIG. 5 is a flowchart showing processing executed in the image server 30.
First, in the modality 10, a patient is imaged and a DICOM file is generated. Then, the generated DICOM file is transmitted to the image server 30.

  In the image server 30, the communication unit 34 receives the DICOM file from the modality 10 (step S1). Next, the control unit 31 divides the DICOM file into a general-purpose image file and a DICOM header file, and the general-purpose image file and the DICOM header file are associated with each other and stored in the storage unit 36 (step S2).

  Next, the control unit 31 acquires the current date and time from the time measuring unit 37, and saves the general-purpose image file in the storage unit 36 based on the acquired current date and time and the date and time of the time stamp attached to the general-purpose image file. The retention period from the date and time when the start is started to the present is calculated. Then, the control unit 31 determines whether or not the storage period of the general-purpose image file has passed one year from the start of storage (step S3). When it is determined that the storage period of the general-purpose image file has passed one year from the start of storage (step S3; YES), the control unit 31 performs JPEG2000 reversible on the general-purpose image file whose storage period has passed one year. Compression conversion is performed (step S4).

Next, the control unit 31 acquires the current date and time from the time measuring unit 37, and saves the general-purpose image file in the storage unit 36 based on the acquired current date and time and the date and time of the time stamp attached to the general-purpose image file. The retention period from the date and time when the start is started to the present is calculated. Then, the control unit 31 determines whether or not the storage period of the general-purpose image file has passed 3 years from the start of storage (step S5). When it is determined that the storage period of the general-purpose image file has passed 3 years from the start of storage (step S5; YES), the control unit 31 does not use JPEG2000 for the general-purpose image file whose storage period has passed 3 years. Lossless compression conversion is performed (step S6).
This completes the processing in the image server 30.

  As described above, according to the image server 30, by dividing the DICOM file into the general-purpose image file and the DICOM header file, only the general-purpose image file can be compressed and stored in the storage unit 36. The amount of medical image data can be reduced. Since the DICOM file occupies most of the data amount is the image data portion, it can be effectively compressed. For this reason, more patients and examination images can be stored. Further, data backup can be performed in a short time due to the reduction of the total file capacity.

  In addition, since the longer the storage period of the general-purpose image file, the higher the compression rate, the data amount can be reduced, and the image size can be adjusted according to the quality of the medical image required for diagnosis. be able to.

  For example, at the beginning of imaging, a high-definition image is required because it is used for interpretation by an interpreting doctor, but after a certain period of time, the frequency of reference is low, and the image quality may be at a level according to the application. Even if it takes some time to develop, it is desirable that the image size is small. Therefore, the free space of the storage unit 36 can be ensured by converting the image into an acceptable image quality as the storage period elapses.

  Further, since the image server 30 stores a general-purpose image file that can respond to requests from any device, it is possible to refer to a medical image without using a dedicated viewer terminal that supports a DICOM file. Further, the data amount can be reduced as compared with the case where both the DICOM file and the general-purpose image file are stored. Since the general-purpose image file is also used when a DICOM file is requested, there is no waste even if it is generated in advance. Further, even after the general-purpose image file is transferred to the low-speed and high-capacity library device, the image can be referred to using a Web browser such as an electronic medical record terminal connected to the network.

  Further, since it is stored in a state of being divided into a general-purpose image file and a DICOM header file, only the DICOM header file needs to be read when only the supplementary information is used. Since the DICOM header file does not include an image portion, processing can be performed at high speed.

  The description in the above embodiment is an example of the medical image management apparatus according to the present invention, and the present invention is not limited to this. The detailed configuration and detailed operation of each part constituting the apparatus can be changed as appropriate without departing from the spirit of the present invention.

  In the above embodiment, the general-purpose image file is uniformly compressed from the bitmap image to the JPEG2000 lossless compressed image and further to the JPEG2000 lossy compressed image according to the storage period. However, the compression method, compression rate, compression The timing of performing may be set for each imaging region and for each modality. For example, in the case of short-term image use such as broken limbs, the image can be compressed at a relatively early stage. On the other hand, in the case of long-term image use that requires follow-up, such as tumors and blood vessels, it is necessary to store an image with a certain level of image quality over a long period of time. Therefore, it is preferable to store the image with an appropriate image quality and image size according to the treatment period. Further, in the above embodiment, the image size is changed in three stages of a bitmap image, a JPEG2000 lossless compressed image, and a JPEG2000 lossy compressed image. However, the image size may be changed in two stages or five stages. Good.

  In the above embodiment, incidental information included in a DICOM file is stored as a DICOM header file. However, each data of incidental information corresponding to a plurality of DICOM files may be stored in a database.

  In the above embodiment, the file designation information is included in the acquisition request received by the image server 30 from another device. However, when the internal configuration of the storage unit 36 of the image server 30 is disclosed in advance. The general-purpose image file or DICOM header file may be specified by directly specifying a URL (Uniform Resource Locator) including a folder name and a file name to be acquired by the user.

  The medical image management apparatus and program according to the present invention may be used in the medical field where image data of medical images is stored for a long period of time.

Explanation of symbols

10 modalities 20 RIS
30 Image server 31 Control unit 32 Operation unit 33 Display unit 34 Communication unit 35 ROM
36 Storage Unit 37 Timekeeping Unit 38 Bus 40 Image Viewer Terminal 50 Electronic Medical Record Terminal 100 Medical Image System N Communication Network

Claims (4)

Receiving means for receiving a DICOM file including image data of medical images and incidental information related to the image data;
Storage means;
The DICOM file received by the receiving unit is divided into an image data file and an incidental information file, stored in the storage unit in association with each other, and after the image data file is started to be stored in the storage unit Control means for compressing the file of the image data based on a compression condition predetermined according to a storage period;
A medical image management apparatus comprising:   The medical image management apparatus according to claim 1, wherein the compression condition is set such that a compression rate is higher as a storage period of the image data file is longer. Computer
Receiving means for receiving a DICOM file including image data of a medical image and incidental information related to the image data;
Storage means,
The DICOM file received by the receiving unit is divided into an image data file and an incidental information file, stored in the storage unit in association with each other, and after the image data file is started to be stored in the storage unit Control means for compressing the image data file based on a compression condition determined in advance according to a storage period;
Program to function as.   4. The program according to claim 3, wherein the compression condition is set such that the compression rate is higher as the storage period of the image data file is longer.

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