With the advent of the information age, digital, standardized and networked surgery has entered the field of medical imaging and developed rapidly. With the application of some brand-new digital imaging technologies in clinic, such as CT, MRI, digital subtraction angiography (DSA), positron emission tomography (PET), computed radiography (CR) and digital radiography (DR), the networking of medical imaging diagnostic equipment has gradually become an inevitable trend in the development of imaging department, and the writing of medical imaging diagnostic reports is required to be computerized, standardized and standardized objectively. The emergence and rapid development of image archiving and communication system (PACS) and medical image diagnosis report system have greatly changed the whole radiology department and improved the position and role of imaging science in clinical medicine.
abstract
PACS is a comprehensive system developed rapidly with the progress of digital imaging technology, computer technology and network technology in recent years, aiming at comprehensively solving the acquisition, display, storage, transmission and management of medical images [1-4]. PACS is divided into five units: medical image acquisition, large-capacity data storage, image display and processing, database management and local area network or wide area network for image transmission [2,4].
PACS is a computer network used to transmit medical images, and the protocol is the premise of information transmission. DICOM is the first widely accepted global medical digital imaging and communication standard. It uses the standard TCP/IP (Transmission Control Protocol/Internet Protocol) network environment to realize the direct networking between medical imaging devices. Therefore, PACS is the core framework of digital medical imaging system, and DICOM3.0 standard is an important network standard and protocol to ensure PACS to become a completely open system.
65438-0998 The Radiology Department of our hospital cooperated with Gehangwei Medical System (GEHW for short) to build a network system of medical imaging diagnostic equipment. It takes DICOM server as the central server, connects digital imaging equipment according to DICOM3.0 standard, and collects, transmits, processes, stores and manages medical digital images.
Materials and methods
First, the institutional environment.
(1) hardware configuration
1.DICOM server: Dell) PowerEdge 2300 server (Pentium 400MHz CPU, 128MB dynamic memory, 9.0GB hot-swappable SICI hard disk× 2, NEC 24× SCSI optical drive, Yamaha 6×4×2 CD-RW×2, Ether Express Pro/65438. 500 Watt Uninterruptible Power Supply (UPS).
2. Digital medical image acquisition equipment: spiral CT: Gehispeed CT/I, DICOM 3.0 interface; Magnetic vibration: GE Signa Horizon LX MRI, DICOM 3.0 interface.
3. Medical image display and processing workstation: Sun Advantage Windows (AW)2.0, 128MB static memory, 20-inch (1in = 2.54 cm) color display, 1280× 1024 display resolution, DICOM 3.0 interface.
4. Laser film printer: 3M Imation) 969 HQ dual printer.
5. Medical image browsing terminals: 7 sets, Pentium II 350 ~ 400 MHz/ Pentium IIIⅲ450 MHz CPU, 64 ~ 128MB memory, 8MB video memory, 6 GB ~ 8.4 GB hard disk, 15 in ~ 17 in display,/kloc-0.
The development and preliminary application of medical image archiving and communication system comes from: the first model network
6. Medical image diagnosis report printing server: two image browsing terminals serve as printing servers at the same time.
7. Laser printer: HP Laserjet 6L gold × 2.
8.:D hub-connecting DE 809TC, 10Mbps.
9. Transmission medium: thin net; Category 5 unshielded twisted pair (UTP); Optical fiber cable.
10. Network structure: star bus topology.
(2) Software
1. Operating system: spiral CT, MRI, AW workstation: UNIX；; DICOM server: Windows NT 4.0 server (English version); Terminal for image browsing and diagnosis report writing: Windows NT 4.0 workstation (Chinese version).
2. Network transmission protocol: standard TCP/IP.
3. Web browser: Netscape Communicator 4.6.
4. Database management system: interbase server/client5.1.1.
5. Development software of medical image browsing and image diagnosis report system: Borland C++ Builder 4.2.
The development and preliminary application of medical image archiving and communication system comes from
6. Medical image browsing terminal: gehw advantage viewer server/client1.01.
7. Medical image diagnosis report system: GEHW medical diagnosis report 1.0.
8. Burner driver software: Gear 4.2.
(3) System structure
Spiral CT, MRI and AW workstations are connected to the main cable (thin cable) according to DICOM3.0 standard, forming a DICOM network with bus topology. DICOM server is connected with each image browsing and diagnosis report writing terminal through twisted pair to form a star topology Ethernet centered on HUB. They are connected by a hub to form a PACS with star bus topology. Spiral CT, MRI and AW workstations are respectively connected to the laser film printer through optical cables for * * * printing. The PACS consists of the following subsystems:
CT/I: ge hispeed CT/I; AW 2.0: Solar Advantage Windows 2.0 NMR: GE Signa Horizon LX NMR; DICOM: Digital Imaging and Communication in Medicine: Ethernet: Ethernet; T-BNC: coaxial cable connector T-connector; Terminator: Terminator; Transceiver: transceiver; UTP: unshielded twisted pair; Thin coaxial cable: thin coaxial cable
1. Digital image acquisition subsystem: directly generate and output high-resolution digital original images from digital imaging devices such as spiral CT and MRI to DICOM server for centralized storage, printing, browsing and post-processing.
2. Digital image transmission subsystem: send the image data stored in the center back to digital imaging equipment such as spiral CT and MRI for printing, comparative reference and post-processing (3D reconstruction, etc.). ).
3. Medical image processing subsystem: window width/window level adjustment, single/multi-image display, partial/full image enlargement, quantitative measurement (CT value, distance, angle and area), continuous playback and various image annotation are carried out on AW workstation and various image browsing and diagnosis report writing terminals.
4. Medical image diagnosis report writing subsystem: writing standardized and standardized medical image diagnosis reports.
5. image central storage subsystem: images are stored in the hard disk of DICOM server in a short time (5 ~ 7 days). When the image data is accumulated to a certain amount (650MB), they will be burned to CD-R (recordable optical disc) for long-term storage.
Second, medical image browsing and image diagnosis reporting system
The software package used in the medical image browsing and image diagnosis report system is Advantage Viewer Server/Client1.05438+0 provided by GEHW. Based on Windows NT Server/Workstation 4.0, the software is divided into two parts: server and client. The server is responsible for the transmission, central storage and database management of medical images. The client software has the functions of medical image browsing and image diagnosis report writing.
The server software includes four modules: image browsing, image management, CD-ROM database and system setup. (1) The picture browsing module has a simple picture browsing function; (2) The image management module includes sub-modules, such as storage, deletion and image output. In these sub-modules, the patient's name, age, sex, CT number, examination serial number, examination type and examination date are used as keywords to search for the required images on the hard disk and CD-ROM of DICOM server, and relevant processing is carried out; (3) that CD database module store the image retrieval information of each CD for query; (4) The system setup module manages the IP addresses of input and output devices.
Medical image browsing software has powerful image processing function, which can access the required images from the hard disk and CD of DICOM server through the network, and browse and post-process the images. Including window width and window level, image, geometry, network, display format, continuous playback and other functional modules. (1) The window width and window level module can set the window width and window level accurately by predefined, user-defined, so that the image can be displayed optimally, and it can also be adjusted by the left mouse button; (2) The image function module can perform scaling (1 ~ 300 times), filtering, contrast (-100 ~ 100), rotation (0 ~ 360) and three primary colors (RGB) processing; (3) Geometry function module can flip the image vertically or horizontally, add grids, process negative images, measure quantitatively (CT value, distance, area, angle) and mark. The post-processed images can be directly output to the diagnosis report system, or saved in different file formats for making slides.
The development and preliminary application of medical image archiving and communication system comes from: the first model network
The medical image diagnosis report system software is embedded in the medical image browsing software, which can directly write the diagnosis report after browsing the image. The input items on the main form of medical diagnosis report, such as name, gender, age, CT number, examination serial number and examination date, can be obtained directly from the database, and the report date is automatically generated by the system. You can select items such as topics and report templates from the drop-down menu. Inspection findings and impressions can be directly extracted from the diagnosis support database and directly or partially modified to form the main body of the diagnosis report. The program provides editing functions such as undo, cut, copy, paste, clear, select all and font. The software can output diagnostic reports in four formats, including 1 ~ 2 typical illustrations. Users can search and read diagnostic reports through 1 or more key fields.
result
After the hardware installation and networking of PACS are completed, the whole PACS is debugged at two levels: basic network connection (TCP/IP) and DicOM horizontal transmission. The transmission of digital images, centralized storage, image processing that is easy for machine processing, mutual compatibility and image communication between different operating systems (UNIX and Windows NT) and DICOM3.0 standards, and image diagnosis in PACS have been successfully realized. At the beginning of 1999, PACS was officially used in CT and MRI rooms of our department, which significantly improved the work efficiency and management level of the department.
discuss
The rapid development of digital technology, computer technology and network technology has promoted the rapid development of medical imaging technology, and also promoted the change of doctors' working mode: doctors are required to be accustomed to watching medical images on the screen of monitors; Retrieve and read medical images by computer, and adjust the window width and window level; Get the required medical images, diagnosis reports and other related information at any time through the computer network.
First, the problems of traditional medical image processing methods
(1) Saving movies requires a lot of storage space. (2) Developing, fixing, washing, drying and archiving require a lot of manpower and financial resources. (3) The manual management of the film library is inefficient, the query is slow, and it is easy to classify films into wrong files. (4) After several years, due to the aging of the film, the images on the film became blurred, which brought great inconvenience to the examination and scientific research. (5) Hard copy CT, MRI and other images to filming, the fixed window width and window position have lost most of the original information, only the information that the surgeon thinks is useful, the image can not be post-processed, and the diagnostic information that is useful for the patient's follow-up visit and other doctors is lost.
Second, the application value of PACS in imaging discipline
(1) Using PACS network technology, images and related materials can be transmitted quickly between CT, MRI and other imaging departments, realizing resource sharing, which is convenient for doctors to call, consult and compare images, and is more conducive to patients to obtain the highest diagnosis and treatment benefits. (2)PACS adopts large-capacity recordable compact disc (CD-R) storage technology, which realizes partial filmlessness, reduces the use and management of films, reduces the wear and tear of laser cameras and film processors, reduces the consumption of developer, saves the space required for film storage and reduces the operating cost. (3) It avoids the borrowing procedures of photos and the loss and misplacement of photos, improves the management of medical imaging materials and improves work efficiency. (4) Multiple images of different periods and different imaging methods can be accessed in different places at the same time, and the images can be compared and compared after reprocessing, which provides convenient conditions for medical personnel and researchers engaged in medical imaging to work, study and study. (5) It is beneficial to computer-aided teaching and further improves the teaching quality. PACS can be used for lossless storage of image data. In the future, when finding valuable images that meet the requirements of teaching content, they will be marked in Chinese and English, made into teaching slides with PowerPoint software, and taught with large-screen multimedia projectors.
The standardized writing function of medical image diagnosis report can print out the image diagnosis report with pictures and texts.
III. Standardization and computerization of diagnostic reports
(1) Basic projects need to be standardized. The general items reflecting the illness in the diagnosis report are relatively complete, and the items for future reference are also relatively complete. (2) Standardization of technical terms in reports. The content is clearly stated and the priorities are clear. First describe the positive signs, then describe the negative signs, first describe the main lesions, and then describe the secondary lesions. The description is consistent with the conclusion. (3) Standardization of basic formats. First describe the general project, then describe the image, then make a conclusion statement, and finally put forward other suggestions for further investigation.
Compared with manual writing, the medical image diagnosis report system has many remarkable advantages: (1) The medical image diagnosis report writing system can save all kinds of image diagnosis data more completely and avoid repeated work. (2) The format of the report is standardized and the handwriting is clear, which overcomes the defect of scribbled handwriting in manual writing report [5]. (3) Graphic image diagnosis report can be printed. (4) patient inquiry and statistical analysis of scientific research cases are fast.
PACS is a science that combines radiology with computers and computer networks. It is difficult to complete the design and use tasks by radiologists or computer and network experts alone, so multi-party cooperation is extremely important.