Validating DICOM Content in a Remote Storage Model

Verifying the integrity of DICOM files transmitted between separate archives (eg, storage service providers, network attached storage, or storage area networks) is of critical importance. The software application described in this article retrieves a specified number of DICOM studies from two different DICOM storage applications; the primary picture archiving and communication system (PACS) and an off-site long-term archive. The system includes a query/retrieve (Q/R) module, storage service class provider (SCP), a DICOM comparison module, and a graphical user interface. The system checks the two studies for DICOM 3.0 compliance and then verifies that the DICOM data elements and pixel data are identical. Discrepancies in the two data sets are recorded with the data elements (tag number, value representation, value length, and value field) and pixel data (pixel value and pixel location) in question. The system can be operated automatically, in batch mode, and manually to meet a wide variety of use cases. We ran this program on a 15% statistical sample of 50,000 studies (7500 studies examined). We found 2 pixel data mismatches (resolved on retransmission) and 831 header element mismatches. We subsequently ran the program against a smaller batch of 1000 studies, identifying no pixel data mismatches and 958 header element mismatches. Although we did not find significant issues in our limited study, given other incidents that we have experienced when moving images between systems, we conclude that it is vital to maintain an ongoing, automatic, systematic validation of DICOM transfers so as to be proactive in preventing possibly catastrophic data loss.     

基于ITK读写DICOM医学图像文件

目的 介绍使用ITK读取DICOM文件文件头信息、访问像素数据以及存储DICOM文件的使用方法,以促进ITK在国内医学图像处理领域的普及应用。方法 使用itk：：ImageFileReader类和itk：：GDCMImageIO类对DICOM文件的文件头进行解析。介绍了使用图像迭代器访问图像像素的方法,熟悉C编程的研究人员快速访问像素数据的方法,及使用itk：：ImageFileWriter类进行图像写操作的方法。结果 使用本文的方法能够获取DICOM医学图像文件头中的医疗信息,读取像素数据,并以DICOM格式存储医学图像信息。结论 即使对DICOM标准和图像格式没有深入的了解,使用ITK也能方便地读写DICOM医学图像文件。     

Proposal for DICOM Multiframe Medical Image Integrity and Authenticity

This paper presents a novel algorithm to successfully achieve viable integrity and authenticity addition and verification of n-frame DICOM medical images using cryptographic mechanisms. The aim of this work is the enhancement of DICOM security measures, especially for multiframe images. Current approaches have limitations that should be properly addressed for improved security. The algorithm proposed in this work uses data encryption to provide integrity and authenticity, along with digital signature. Relevant header data and digital signature are used as inputs to cipher the image. Therefore, one can only retrieve the original data if and only if the images and the inputs are correct. The encryption process itself is a cascading scheme, where a frame is ciphered with data related to the previous frames, generating also additional data on image integrity and authenticity. Decryption is similar to encryption, featuring also the standard security verification of the image. The implementation was done in JAVA, and a performance evaluation was carried out comparing the speed of the algorithm with other existing approaches. The evaluation showed a good performance of the algorithm, which is an encouraging result to use it in a real environment.     

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.     

基于XML的DICOM SR信息模型的研究

本文主要研究DICOM SR的信息模型，提出了DICOM SR数据的XML表示和DICOM模板XML建模的方法，解决了以往技术上难以表示复杂的DICOM SR数据的困难，实现SR的DICOM编码到XML编码的转换及建模。     

由DICOM医学图像文件获得设备无关位图的方法

目的:根据临床调查.DICOM3.0医学图像文件格式的解析及解决其显示问题是医学图像处理的基础,对医学影像技术的研究有重要意义.方法:首先针对DICOM3.0标准,系统分析了DICOM医学图像文件格式,主要阐述了文件信息头和数据元素的格式,提出了在Windows平台下利用线性调窗实现DICOM图像的DIB位图显示.结果:利用线性调窗成功实现了CT、MR图像的显示,同时针对默认状态下显示效果欠佳,采用手动调窗改善显示效果.结论:实验证明,该方法能较好地实现DICOM医学图像的显示,满足一定的临床需求,同时也为后续工作奠定基础.     

Providing Integrity,Authenticity, and Confidentiality for Header and Pixel Data of DICOM Images

Exchange of medical images over public networks is subjected to different types of security threats. This has triggered persisting demands for secured telemedicine implementations that will provide confidentiality, authenticity, and integrity for the transmitted images. The medical image exchange standard (DICOM) offers mechanisms to provide confidentiality for the header data of the image but not for the pixel data. On the other hand, it offers mechanisms to achieve authenticity and integrity for the pixel data but not for the header data. In this paper, we propose a crypto-based algorithm that provides confidentially, authenticity, and integrity for the pixel data, as well as for the header data. This is achieved by applying strong cryptographic primitives utilizing internally generated security data, such as encryption keys, hashing codes, and digital signatures. The security data are generated internally from the header and the pixel data, thus a strong bond is established between the DICOM data and the corresponding security data. The proposed algorithm has been evaluated extensively using DICOM images of different modalities. Simulation experiments show that confidentiality, authenticity, and integrity have been achieved as reflected by the results we obtained for normalized correlation, entropy, PSNR, histogram analysis, and robustness.     

DICOM标准的语义扩充

医学图像数字成像和通信（Digital Imaging and Communicationsin Medicine，DICOM）标准是美国电气制造商联合会（NEMA）和美国放射学会（ACR）为了医学图像的存储和传输而制定的标准，在医学上得到广泛的应用。但该标准目前没有充分定义图像语义内容，从而使得实际中不能有效的实现DICOM的基于语义的应用。本文讨论了医学图像中的语义描述层次结构，概述了DICOM标准中对图像的描述方法并指出了该标准对图像语义内容描述的不足，给出了使用DICOM标准中私有属性对DICOM图像语义内容进行扩充的方法。     

DICOM格式医学图像及其图像信息的显示

目的:DICOM(digital image andcommunicati on onmedicine)的普及不仅提供了高效率的图像存取和使用服务,也为医院中包括图像信息在内的综合医学信息管理奠定了基础。因此对DICOM格式图像显示的研究具有重要意义。方法:首先对DICOM医学图像文件的格式及数据编码规则进行了阐述,然后分四步具体介绍了图像及其信息的显示流程。结果:基于Windows平台,成功将DICOM图像及其信息显示出来。结论:实验证明,该方法能够较好地显示DICOM医学图像,同时也为后续工作奠定了基础。     

PACS中的DICOM标准分析及应用

DICOM是PACS系统中被国际认可的医学图像标准。本文分析了DICOM标准的主要部分，特别是信息对象定义、服务类和服务对象、数据组织格式、通讯机制等部分。结合广州医学院附属第二医院的实际情况，阐述了DICOM标准如何在PACS中应用。     

基于IHE的DICOM SR原理及其在PACS中设计与实现

本文首先分析目前国内医院信息化现状,然后针对其弊端结合对DICOM SR原理解析,提出了符合国际标准和技术规范的结构化诊断报告模型,并阐述该模型在全院PACS应用中的实现.     

应用DICOM标准实现放射治疗计划系统的共享

我们基于医学数字图像通讯标准 (DICOM) ,设计了 RT S.S,RT Plan及 RT Image 3个 DICOM对象 ,完成了不同放射治疗计划系统之间的信息共享 ,实现不同设备厂商不同放射治疗计划系统之间的信息交换和共享。     

Teaching DICOM by Problem Solving

The Digital Imaging and Communications in Medicine (DICOM) is the standard for encoding and communicating medical imaging information. It is used in radiology as well as in many other imaging domains such as ophthalmology, dentistry, and pathology. DICOM information objects are used to encode medical images or information about the images. Their usage outside of the imaging department is increasing, especially with the sharing of medical images within Electronic Health Record systems. However, learning DICOM is long and difficult because it defines and uses many specific abstract concepts that relate to each other. In this paper, we present an approach, based on problem solving, for teaching DICOM as part of a graduate course on healthcare information. The proposed approach allows students with diversified background and no software development experience to grasp a large breadth of knowledge in a very short time.     

Streamlining Importation of Outside Prior DICOM Studies into an Imaging System

A patient has an imaging study performed at one facility and has the study exported to portable media. Later, the patient takes the media to a different institution. The study on that media may need to be imported into that new institution’s imaging system. This would be done to avoid a repeat examination, or so that the study can be on file for reference purposes. Importing prior studies is best performed by creating a new order on the institution’s imaging system and then associating the DICOM objects from the prior study with it. In this way the prior study is actually inserted into the imaging system’s electronic health record (EHR) and is properly indexed so that it can be identified and later retrieved as needed. In the past at the Department of Veterans Affairs (VA), importing prior DICOM studies into the VA systems had been a very slow labor-intensive process that took anywhere from 10 to 30 min to import a single study. We have developed a new DICOM Importer application that reduces the manual effort to import a prior study to less than a minute. We have redesigned and automated the process to make it much more efficient for the user. The Importer also handles contract examinations that are ordered by the VA and performed at outside imaging facilities, with similar time savings. This work is important because is addresses one of the major unsolved problems with import reconciliation workflow: how to efficiently handle the importing of prior studies.     

一种DICOM文件并行查找算法的设计与实现

目的为提高DICOM文件查找的速度和效率。方法在分析DICOM文件查找的基本原理基础上,设计一种基于任务等分策略的文件并行查找算法,并基于．NETF ramework 4和Leadtools DICOM开发包实现该算法。该算法特点是采用多线程并行技术,通过任务等分和多核并行实现DICOM文件并行查找。在HPDL380G5服务器上对并行算法进行性能测试,获得并行加速比曲线图。结果测试表明该算法具有良好的并行性能,可显著提高DICOM文件查找效率。结论采用任务等分策略和多线程并行模型,能够有效提高DICOM文件查找的速度和效率。     

基于B/S架构的DICOM结构化报告的设计与应用

本文介绍了在以B／S架构为苯础的PACS工作站上设计与实现DICOM结构化报告应用的方法。设计依照DICOMSR标准，以XML作为信息交换的方式，对DICOMSR进行解析与转换，并利用Web服务发布结构化诊断报告。相比传统的自然文本语言报告，DICOM结构化报告具有结构性、标准性等特点，并为报告生成、分发和管理提供了一个有效的机制。     

WWW和DICOM网关的实现

讨论了ＷＷＷ与ＤＩＣＯＭ网关的必要性及其实现方法和实现的结果,提出了一种新的医生与医学图像设备（包括ＣＴ、ＭＲＩ、超声等设备）及ＰＡＣＳ的交互方式。文中指出：ＷＷＷ与ＤＩＣＯＭ网关是专用标准与通用标准之间的转换,实现这一转换将有利于医疗信息系统的集成及实现远程医疗信息系统。     

基于DICOM标准的EECP血液动力学波形数据转换的研究

目的：将目前增强型体外反搏（EECP）设备采集到的二进制数据文件转换为DICOM血液动力学波形文件。方法：在深入研究DICOM信息模型、DICOM波形文件结构、数据元素结构、嵌套数据集结构、波形IOD模块结构等的基础上，利用Visual C＋＋．Net工具，运用C＋＋面向对象编程思想，把数据元素、嵌套数据集、波形IOD及其操作服务抽象成类，再分别读取二进制数据文件的相关信息赋给波形类对应的数据成员，最后调用有关成员函数将其存储为DICOM波形文件。结果：设计出了基于DICOM标准的EECP血液动力学波形数据转换的应用程序。结论：DICOM标准的不断应用将涵盖所有医学成像和信号类设备，EECP数据的DICOM标准化转换，为其共享和充分利用提供了重要前提。