PACS Viewer Based on Java Applet in B／S Architecture

PACS can be applied in the network architecture of Client/Server (C/S) and Browser/Server (B/S) in current application of hospital information system. PACS Viewer of B/S model is realized by means of the browser commonly, but web browser does not support DICOM standard. In this article, how to use Java Applet to realize the display and operations of DICOM images will be discussed. The lightweight method to view DICOM images is very fit for telemedical treatment, and the situations not require strong ability in image operations。     

MyCases—A Portable Application for Radiologic Case Collections

Radiologists come across interesting patient cases almost every day. This work proposes a novel case database server for quick and easy storage of such cases including whole image series, patient data, and annotations. Cases can be added to the database by saving DICOM images into a predefined directory on the local network. The application automatically extracts patient and study data from the DICOM header and saves it in the database while images are stored as anonymized JPEG files. Users can mark their cases as private or public (visible to all users). Different data fields for annotations and categorization of a case are available. The user frontend also provides several retrieval mechanisms allowing for browsing the cases and performing different kinds of search queries. The stored series can be scrolled interactively in the form of scrollable image stacks. The project is realized as a web-based application using a portable web and database server software package (XAMPP). This makes the system very lightweight and easy to run on almost any desktop computer, even from a USB flash drive, without the need for deeper IT knowledge and administrative rights.     

Establishing a Web-Based DICOM Teaching File Authoring Tool Using Open-Source Public Software

Online teaching files are an important source of educational and referential materials in the radiology community. The commonly used Digital Imaging and Communications in Medicine (DICOM) file format of the radiology community is not natively supported by common Web browsers. The ability of the Web server to convert and parse DICOM is important when the DICOM-converting tools are not available. In this paper, we describe our approach to develop a Web-based teaching file authoring tool. Our server is built using Apache Web server running on FreeBSD operating system. The dynamic page content is produced by Hypertext Preprocessor (PHP). Digital Imaging and Communications in Medicine images are converted by ImageMagick into Joint Photographic Experts Group (JPEG) format. Digital Imaging and Communications in Medicine attributes are parsed by dicom3tools and stored in PostgreSQL database. Using free software available from the Internet, we build a Web service that allows radiologists to create their own online teaching file cases with a common Web browser.     

Development of a Next-Generation Automated DICOM Processing System in a PACS-Less Research Environment

The use of clinical imaging modalities within the pharmaceutical research space provides value and challenges. Typical clinical settings will utilize a Picture Archive and Communication System (PACS) to transmit and manage Digital Imaging and Communications in Medicine (DICOM) images generated by clinical imaging systems. However, a PACS is complex and provides many features that are not required within a research setting, making it difficult to generate a business case and determine the return on investment. We have developed a next-generation DICOM processing system using open-source software, commodity server hardware such as Apple Xserve®, high-performance network-attached storage (NAS), and in-house-developed preprocessing programs. DICOM-transmitted files are arranged in a flat file folder hierarchy easily accessible via our downstream analysis tools and a standard file browser. This next-generation system had a minimal construction cost due to the reuse of all the components from our first-generation system with the addition of a second server for a few thousand dollars. Performance metrics were gathered and the system was found to be highly scalable, performed significantly better than the first-generation system, is modular, has satisfactory image integrity, and is easier to maintain than the first-generation system. The resulting system is also portable across platforms and utilizes minimal hardware resources, allowing for easier upgrades and migration to smaller form factors at the hardware end-of-life. This system has been in production successfully for 8 months and services five clinical instruments and three pre-clinical instruments. This system has provided us with the necessary DICOM C-Store functionality, eliminating the need for a clinical PACS for day-to-day image processing.     

基于NT服务的DICOM服务器端软件的设计

本文详细介绍了Windows NT以及Windows 2000操作系统下NT系统服务的设计过程，以及医学影像系统中数字图像通讯协议(DICOM)，并以此为基础，介绍了DICOM服务器端软件的系统服务程序的设计流程，以实现DICOM协议中服务类提供方(SCP)的功能。     

The department of veterans affairs integration of imaging into the healthcare enterprise using the VistA hospital information system and Digital Imaging and Communications in Medicine

The United States Department of Veterans Affairs is integrating imaging into the healthcare enterprise by using the Digital Imaging and Communication in Medicine (DICOM) standard protocols. Image management is directly integrated into the VistA Hospital Information System (HIS) software and clinical database. Radiology images are acquired with DICOM and are stored directly in the HIS database. Images can be displayed on low-cost clinician’s workstations throughout the medical center. High-resolution diagnostic quality multimonitor VistA workstations with specialized viewing software can be used for reading radiology images. Two approaches are used to acquire and handle images within the radiology department. Some sites have a commercial Picture Archiving and Communications System (PACS) interfaced to the VistA HIS, whereas other sites use the direct image acquisition and integrated diagnostic display capabilities of VistA itself. A small set of DICOM services has been implemented by VistA to allow patient and study text data to be transmitted to image producing modalities and the commercial PACS, and to enable images and study data to be transferred back. DICOM has been the cornerstone in the ability to integrate imaging functionality into the healthcare enterprise. Because of its openness, it allows the integration of system components from commercial and noncommercial sources to work together to provide functional cost-effective solutions.     

DICOM医学图像采集的方法与实践

医学图像采集是PACS的重要环节,也是PACS实用化的关键。本文比较了几种常见的图像采集方法,重点介绍了通过DICOM接口的图像采集,在详细阐明了DICOM网络的概念和DICOM消息交换的规范之后,介绍了我们编写的DICOM医学图像采集软件,本软件是在Windows平台上利用SocketAPI编写而成,提供了DICOM标准定义的验证、存储、查询和检索等服务,测试结果表明,本软件能够顺利地与成像设备连接并采集图像。     

The Clinical Application of a PACS-Dependent 12-Lead ECG and Image Information System in E-Medicine and Telemedicine

This study presents a software technology to transform paper-based 12-lead electrocardiography (ECG) examination into (1) 12-lead ECG electronic diagnoses (e-diagnoses) and (2) mobile diagnoses (m-diagnoses) in emergency telemedicine. While Digital Imaging and Communications in Medicine (DICOM)-based images are commonly used in hospitals, the development of computerized 12-lead ECG is impeded by heterogeneous data formats of clinically used 12-lead ECG instrumentations, such as Standard Communications Protocol (SCP) ECG and Extensible Markup Language (XML) ECG. Additionally, there is no data link between clinically used 12-lead ECG instrumentations and mobile devices. To realize computerized 12-lead ECG examination procedures and ECG telemedicine, this study develops a DICOM-based 12-lead ECG information system capable of providing clinicians with medical images and waveform-based ECG diagnoses via Picture Archiving and Communication System (PACS). First, a waveform-based DICOM-ECG converter transforming clinically used SCP-ECG and XML-ECG to DICOM is applied to PACS for image- and waveform-based DICOM file manipulation. Second, a mobile Structured Query Language database communicating with PACS is installed in physicians’ mobile phones so that they can retrieve images and waveform-based ECG ubiquitously. Clinical evaluations of this system indicated the following. First, this developed PACS-dependent 12-lead ECG information system improves 12-lead ECG management and interoperability. Second, this system enables the remote physicians to perform ubiquitous 12-lead ECG and image diagnoses, which enhances the efficiency of emergency telemedicine. These findings prove the effectiveness and usefulness of the PACS-dependent 12-lead ECG information system, which can be easily adopted in telemedicine.     

Benchmark testing the Digital Imaging Network-Picture Archiving and Communications System proposal of the Department of Defense

The Department of Defense issued a Request for Proposal (RFP) for its next generation Picture Archiving and Communications System in January of 1997. The RFP was titled Digital Imaging Network-Picture Archiving and Communications System (DIN-PACS). Benchmark testing of the proposed vendors' systems occurred during the summer of 1997. This article highlights the methods for test material and test system organization, the major areas tested, and conduct of actual testing. Department of Defense and contract personnel wrote test procedures for benchmark testing based on the important features of the DIN-PACS Request for Proposal. Identical testing was performed with each vendor's system. The Digital Imaging and Communications in Medicine (DICOM) standard images used for the Benchmark Testing included all modalities. The images were verified as being DICOM standard compliant by the Mallinckrodt Institute of Radiology, Electronic Radiology Laboratory. The Johns Hopkins University Applied Physics Laboratory prepared the Unix-based server for the DICOM images and operated it during testing. The server was loaded with the images and shipped to each vendor's facility for on-site testing. The Defense Supply Center, Philadelphia (DSCP), the Department of Defense agency managing the DIN-PACS contract, provided representatives at each vendor site to ensure all tests were performed equitably and without bias. Each vendor's system was evaluated in the following nine major areas: DICOM Compliance; System Storage and Archive of Images; Network Performance; Workstation Performance; Radiology Information System Performance; Composite Health Care System/Health Level 7 communications standard Interface Performance; Teleradiology Performance; Quality Control; and Failover Functionality. These major sections were subdivided into workable test procedures and were then scored. A combined score for each section was compiled from this data. The names of the involved vendors and the scoring for each is contract sensitive and therefore can not be discussed. All of the vendors that underwent the benchmark testing did well. There was no one vendor that was markedly superior or inferior. There was a typical bell shaped curve of abilities. Each vendor had their own strong points and weaknesses. A standardized benchmark protocol and testing system for PACS architectures would be of great value to all agencies planning to purchase a PACS. This added information would assure the purchased system meets the needed functional requirements as outlined by the purchasers PACS Request for Proposal.     

Medical Image Resource Center–making electronic teaching files from PACS

A picture archive and communications system (PACS) is a rich source of images and data suitable for creating electronic teaching files (ETF). However, the potential for PACS to support nonclinical applications has not been fully realized: at present there is no mechanism for PACS to identify and store teaching files; neither is there a standardized method for sharing such teaching images. The Medical Image Resource Center (MIRC) is a new central image repository that defines standards for data exchange among different centers. We developed an ETF server that retrieves digital imaging and communication in medicine (DICOM) images from PACS, and enables users to create teaching files that conform to the new MIRC schema. We test-populated our ETF server with illustrative images from the clinical case load of the National Neuroscience Institute, Singapore. Together, PACS and MIRC have the potential to benefit radiology teaching and research.     

HRPS数字化医院管理系统设计

HRPS数字化医院管理系统是对HIS、RIS、PACS和Internet技术的整合和一体化设计。系统采用模块化结构，其中HIS包括HAS、RIS、PACS服务器、管理终端和临床终端，RIS包括各种影像设备、PACS和影像网络中心。硬件构架采用Web的多层体系结构Browse/Server模式，网络采用ATM技术，信息交换标准为DI-COM3.0，数据库为SQL Server6.5/7.0、Oracle，开发工具为PowerBuilder6.5。系统可在一个完整的平台上实现系统功能、管理功能、信息处理功能和通讯功能，具有共享性、安全性、开放性、可扩展等特点。目前已在40余家医院成功应用，实现了数字化、网络化和无胶片的医院现代化管理。     

Clinical Evaluation of Compression Ratios using JPEG2000 on Computed Radiography Chest Images

The efficient compression of radiographic images is of importance for improved storage and network utilization in support of picture archiving and communication systems (PACS) applications. The DICOM Working Group 4 adopted JPEG2000 as an additional compression standard in Supplement 61 over the existing JPEG. The wavelet-based JPEG2000 can achieve higher compression ratios with less distortion than the Discrete Cosine Transform (DCT)-based JPEG algorithm. However, the degradation of JPEG2000-compressed computed radiography (CR) chest images has not been tested comprehensively clinically. The authors evaluated the diagnostic quality of JPEG2000-compressed CR chest images with compression ratios from 5:1 to 200:1. An ROC (receiver operating characteristic analysis) and t test were performed to ascertain clinical performance using the JPEG2000-compressed images. The authors found that compression ratios as high as 20:1 can be utilized without affecting lesion detectability. Significant differences between the original and the compressed CR images were not recognized up to compression ratio of 50:1 within a confidence level of 99%.     

基于Web技术的医学图像发布系统

目的：应用Java技术开发一个基于Web技术的操作简易、通用性强的医学图像发布环境。方法：采用Web服务器来查询和提取存储在DICOM服务器中的医学图像，客户端使用嵌有JavaApplet小程序的Web浏览器来访问Web服务器，完成客户端对服务器端医学图像的提取，JavaApplet小程序利用Web浏览器实现其图像操作。结果：我们使用Java技术开发一个基于Web技术的医学图像发布环境，完成了客户机通过Intemet对服务器端医学图像的读取操作，实现了异地专家的在线交流。结论：与大多数传统的PACS相比．基于Web技术的PACS系统易于安装和维护，与运行平台无关，可以高效的显示、处理医学图像，容易和使用Web技术构建的PACS系统整合。设置适当的安全防范措施，用户可以在医院外部实现对该系统的访问。Intemet技术的简易性和可扩展性使得该系统与传统PACS系统相比有着更大的优越性。     

A Mobile Phone Integrated Health Care Delivery System of Medical Images

With the growing computing capability of mobile phones, a handy mobile controller is developed for accessing the picture archiving and communication system (PACS) to enhance image management for clinicians with nearly no restriction in time and location using various wireless communication modes. The PACS is an integrated system for the distribution and archival of medical images that are acquired by different imaging modalities such as CT (computed tomography) scanners, CR (computed radiography) units, DR (digital radiography) units, US (ultrasonography) scanners, and MR (magnetic resonance) scanners. The mobile controller allows image management of the PACS including display, worklisting, query and retrieval of medical images in DICOM format. In this mobile system, a server program is developed in a PACS Web server which serves as an interface for client programs in the mobile phone and the enterprise PACS for image distribution in hospitals. The application processing is performed on the server side to reduce computational loading in the mobile device. The communication method of mobile phones can be adapted to multiple wireless environments in Hong Kong. This allows greater feasibility to accommodate the rapidly changing communication technology. No complicated computer hardware or software is necessary. Using a mobile phone embedded with the mobile controller client program, this system would serve as a tool for heath care and medical professionals to improve the efficiency of the health care services by speedy delivery of image information. This is particularly important in case of urgent consultation, and it allows health care workers better use of the time for patient care.     

PACS图像工作站三维可视化方法研究

讨论了 PACS图像工作站获取序列扫描图像的途径 ,PACS应用实体之间采用面向对象的客户 /服务器结构 ,利用 DICOM标准建立的服务类实现扫描图像的存储、查询和传输功能 ,并以网络数据库的方式实现序列图像的有序存储和分类管理。图像工作站将获取的 DICOM格式序列图像转换成体素场 ,采用面绘制与体绘制算法生成感兴趣对象的三维图像 ,使重建的图像获得清晰的三维细节和真实感 ,文中给出了 3组应用实例的结果     

Enterprise-scale image distribution with a Web PACS

The integration of images with existing and new health care information systems poses a number of challenges in a multi-facility network: image distribution to clinicians; making DICOM image headers consistent across information systems; and integration of teleradiology into PACS. A novel, Web-based enterprise PACS architecture introduced at Massachusetts General Hospital provides a solution. Four AMICAS Web/Intranet Image Servers were installed as the default DICOM destination of 10 digital modalities. A fifth AMICAS receives teleradiology studies via the Internet. Each AMICAS includes: a Java-based interface to the IDXrad radiology information system (RIS), a DICOM autorouter to tape-library archives and to the Agfa PACS, a wavelet image compressor/decompressor that preserves compatibility with DICOM workstations, a Web server to distribute images throughout the enterprise, and an extensible interface which permits links between other HIS and AMICAS. Using wavelet compression and Internet standards as its native formats, AMICAS creates a bridge to the DICOM networks of remote imaging centers via the Internet. This teleradiology capability is integrated into the DICOM network and the PACS thereby eliminating the need for special teleradiology workstations. AMICAS has been installed at MGH since March of 1997. During that time, it has been a reliable component of the evolving digital image distribution system. As a result, the recently renovated neurosurgical ICU will be filmless and use only AMICAS workstations for mission-critical patient care.     

A comparison of wavelet and Joint Photographic Experts Group lossy compression methods applied to medical images

This presentation focuses on the quantitative comparison of three lossy compression methods applied to a variety of 12-bit medical images. One Joint Photographic Exports Group (JPEG) and two wavelet algorithms were used on a population of 60 images. The medical images were obtained in Digital Imaging and Communications in Medicine (DICOM) file format and ranged in matrix size from 256 × 256 (magnetic resonance [MR]) to 2,560 × 2,048 (computed radiography [CR], digital radiography [DR], etc). The algorithms were applied to each image at multiple levels of compression such that comparable compressed file sizes were obtained at each level. Each compressed image was then decompressed and quantitative analysis was performed to compare each compressed-thendecompressed image with its corresponding original image. The statistical measures computed were sum of absolute differences, sum of squared differences, and peak signal-to-noise ratio (PSNR). Our results verify other research studies which show that wavelet compression yields better compression quality at constant compressed file sizes compared with JPEG. The DICOM standard does not yet include wavelet as a recognized lossy compression standard. For implementers and users to adopt wavelet technology as part of their image management and communication installations, there has to be significant differences in quality and compressibility compared with JPEG to justify expensive software licenses and the introduction of proprietary elements in the standard. Our study shows that different wavelet implementations vary in their capacity to differentiate themselves from the old, established lossy JPEG.     

System Integration and DICOM Image Creation for PET-MR Fusion

This article demonstrates a gateway system for converting image fusion results to digital imaging and communication in medicine (DICOM) objects. For the purpose of standardization and integration, we have followed the guidelines of the Integrated Healthcare Enterprise technical framework and developed a DICOM gateway. The gateway system combines data from hospital information system, image fusion results, and the information generated itself to constitute new DICOM objects. All the mandatory tags defined in standard DICOM object were generated in the gateway system. The gateway system will generate two series of SOP instances of each PET-MR fusion result; SOP (Service Object Pair) one for the reconstructed magnetic resonance (MR) images and the other for position emission tomography (PET) images. The size, resolution, spatial coordinates, and number of frames are the same in both series of SOP instances. Every new generated MR image exactly fits with one of the reconstructed PET images. Those DICOM images are stored to the picture archiving and communication system (PACS) server by means of standard DICOM protocols. When those images are retrieved and viewed by standard DICOM viewing systems, both images can be viewed at the same anatomy location. This system is useful for precise diagnosis and therapy.