Evaluation of Self-Contained PACS Viewers on CD-ROM

Providing patients and clinicians with self-contained PACS viewer on CD format is a common and necessary tool to share vital imaging data. However, to be useful, this tool should be reliable, robust, and convenient. Numerous PACS viewer options are available, often without empirical data to guide in choosing one for routine use. To assist in making a standardized choice for our institution, we chose four common viewers, benchmarked on four different workstations reflecting the variety of environments used by non-radiologist clinicians who would receive a CD. Four CD-based DICOM viewers from eFilm, Philips, Pacsgear Gearview, and iSite were examed on two radiology PACS workstations, a standard desktop computer, and a laptop using a test case consisting of a multi-series CTA with 13 series and 3,035 total images. Multiple objective measures, subjective measures, and presence of key features were evaluated including program time to load, image time to load, cine/movie mode, ability to adequately window and level, pan and zoom functionality, basic measurement tools, and perceived lag when scrolling through a multi-image series. Substantial differences in speed of operation and behavior on multiple systems were documented, which could potentially add several minutes to the time required to open and view a patient’s imaging data. The eFilm and iSite viewers operated consistently and reliably across all tested computer environments. The iSite viewer, having among the quickest load times in the group tested and consistently low subjective scroll lag during series viewing, and also beneficially allowing partial viewing while images load in the background, was found to generate the best overall user experience. Because of these significant differences, we have recommended that our institution standardize all patient imaging CD creation using the iSite viewer.     

Evaluation of Free,Open-source,Web-based DICOM Viewers for the Indian National Telemedicine Service (eSanjeevani)

The Digital Image and Communications in Medicine (DICOM) viewer is a very useful component in telemedicine applications. Owing to increased demand, adoption, and prospects of browser-based software in the recent past, web-based DICOM viewers have gained significant ground. There are myriad web-based DICOM viewers which are open source and are available free of cost as stand-alone applications. These freely available tools have rich functionality like the commercial ones. To find an optimal DICOM viewer for integration with a web-based telemedicine solution is quite a challenge, and no research has gone into assessing these freely available DICOM viewers. This research assessed a range of web-based, open-source, and freely available DICOM viewers from the perspective of their integration with the Indian National Telemedicine Solution (eSanjeevani). To introduce teleradiology module in eSanjeevani, a study is carried out to enable viewing of radiological images through DICOM viewer. eSanjeevani is being prepared for a national roll-out at 155,000 health and wellness centers across rural India by the Ministry of Health and Family Welfare (Government of India) under the Ayushman Bharat Scheme (the world’s largest health insurance scheme). In total, 13 free, open-source, and web-based DICOM viewers were identified for evaluation; however, only six were shortlisted as assessed. This study can serve as a one-stop source for researchers looking for a suitable DICOM viewer for their healthcare IT applications.     

Eye-tracking device comparisons of three methods of magnetic resonance image series displays

This study evaluated the effectiveness of three kinds of display methods for magnetic resonance (MR) image interpretation using an eye-tracking device. Seven radiologists interpreted head MR studies by using a single monitor (17-inch, 1,024×1,280 bit) in the 4 images/screen display format. Three paging modes were compared: (A) rapid paging only, (B) multiple image series display at the same slice position with consecutive rapid paging, and (C) simultaneous display of multiple series with each image series being browsed independently. Using an eye-mark camera, the radiologist's point of fixation and the duration of fixation were recorded during actual image interpretation. In mode A, the duration of fixation was short, and the points of fixation were distributed randomly over the visual field. In mode B, the points of fixation were clustered chiefly on a specific image series. In mode C, the points of fixation were not clustered on a specified series, but the duration of viewing the T2 series was relatively long. The total tracing area in mode B and C was smaller than that in mode A. Multiple series display, in which selected key series of slices could be viewed effectively, was found to be suitable for MR image interpretation.     

Handheld Device Review of Abdominal CT for the Evaluation of Acute Appendicitis

Advances in handheld computing now allow review of DICOM datasets from remote locations. As the diagnostic ability of this tool is unproven, we evaluated the ability to diagnose acute appendicitis on abdominal CT using a mobile DICOM viewer. This HIPAA compliant study was IRB-approved. Twenty-five abdominal CT studies from patients with RLQ pain were interpreted on a handheld device (iPhone) using a DICOM viewer (OsiriX mobile) by five radiologists. All patients had surgical confirmation of acute appendicitis or follow-up confirming no acute appendicitis. Studies were evaluated for the ability to find the appendix, maximum appendiceal diameter, presence of an appendicolith, periappendiceal stranding and fluid, abscess, and an assessment of the diagnosis of acute appendicitis. Results were compared to PACS workstation. Fifteen cases of acute appendicitis were correctly identified on 98% of interpretations, with no false-positives. Eight appendicoliths were correctly identified on 88% of interpretations. Three abscesses were correctly identified by all readers. Handheld device measurement of appendiceal diameter had a mean 8.6% larger than PACS measurements (p = 0.035). Evaluation for acute appendicitis on abdominal CT studies using a portable device DICOM viewer can be performed with good concordance to reads performed on PACS workstations.     

Assessment of DICOM Viewers Capable of Loading Patient-specific 3D Models Obtained by Different Segmentation Platforms in the Operating Room

Patient-specific 3D models obtained by the segmentation of volumetric diagnostic images play an increasingly important role in surgical planning. Surgeons use the virtual models reconstructed through segmentation to plan challenging surgeries. Many solutions exist for the different anatomical districts and surgical interventions. The possibility to bring the 3D virtual reconstructions with native radiological images in the operating room is essential for fostering the use of intraoperative planning. To the best of our knowledge, current DICOM viewers are not able to simultaneously connect to the picture archiving and communication system (PACS) and import 3D models generated by external platforms to allow a straight integration in the operating room. A total of 26 DICOM viewers were evaluated: 22 open source and four commercial. Two DICOM viewers can connect to PACS and import segmentations achieved by other applications: Synapse 3D® by Fujifilm and OsiriX by University of Geneva. We developed a software network that converts diffuse visual tool kit (VTK) format 3D model segmentations, obtained by any software platform, to a DICOM format that can be displayed using OsiriX or Synapse 3D. Both OsiriX and Synapse 3D were suitable for our purposes and had comparable performance. Although Synapse 3D loads native images and segmentations faster, the main benefits of OsiriX are its user-friendly loading of elaborated images and it being both free of charge and open source.     

User Interface of a Teleradiology System for the MR Assessment of Multiple Sclerosis

The aim of this study was to assess the image display of a web-based teleradiology system that uses a common web browser and has no need of proprietary applets, plug-ins, or dedicated software for DICOM display. The teleradiology system (TS) is connected to the Internet by ADSL and to radiological modalities using the DICOM standard with TCP/IP. Images were displayed on a PC through Internet connection with the remote TS using a common web browser. MS lesion number and volume in T1- and T2-weighted images (T1w and T2w, respectively) of 30 brain MR studies were quantified using both the TS and a conventional software. Wilcoxon signed ranks test and intraclass correlation coefficient (ICC) were used to assess the variability and concordance between intra- and inter-observer and TS and conventional DICOM viewer, setting significance at p < 0.05. No significant differences in T1w and T2w volumes between the TS and the conventional software were found by either operator. The ICC results showed a high level of inter-operator agreement in volume estimation in T1w and T2w images using the two systems. Quantitative assessment of MS lesion volumes in T1w and T2w images with a user interface of a teleradiology system that allows the consultation by means of a common web browser, without the need for proprietary plug-ins, applets, or dedicated software for DICOM display showed no significant differences from, and almost complete agreement with, conventional DICOM viewers.     

Videos of conspecifics elicit interactive looking patterns and facial expressions in monkeys

A broader understanding of the neural basis of social behavior in primates requires the use of species-specific stimuli that elicit spontaneous, but reproducible and tractable behaviors. In this context of natural behaviors, individual variation can further inform about the factors that influence social interactions. To approximate natural social interactions similar to those documented by field studies, we used unedited video footage to induce in viewer monkeys spontaneous facial expressions and looking patterns in the laboratory setting. Three adult male monkeys (Macaca mulatta), previously behaviorally and genetically (5-HTTLPR) characterized, were monitored while they watched 10 s video segments depicting unfamiliar monkeys (movie monkeys) displaying affiliative, neutral, and aggressive behaviors. The gaze and head orientation of the movie monkeys alternated between "averted" and "directed" at the viewer. The viewers were not reinforced for watching the movies, thus their looking patterns indicated their interest and social engagement with the stimuli. The behavior of the movie monkey accounted for differences in the looking patterns and facial expressions displayed by the viewers. We also found multiple significant differences in the behavior of the viewers that correlated with their interest in these stimuli. These socially relevant dynamic stimuli elicited spontaneous social behaviors, such as eye-contact induced reciprocation of facial expression, gaze aversion, and gaze following, that were previously not observed in response to static images. This approach opens a unique opportunity to understanding the mechanisms that trigger spontaneous social behaviors in humans and nonhuman primates.     

An efficient architecture to support digital pathology in standard medical imaging repositories

In the past decade, digital pathology and whole-slide imaging (WSI) have been gaining momentum with the proliferation of digital scanners from different manufacturers. The literature reports significant advantages associated with the adoption of digital images in pathology, namely, improvements in diagnostic accuracy and better support for telepathology. Moreover, it also offers new clinical and research applications. However, numerous barriers have been slowing the adoption of WSI, among which the most important are performance issues associated with storage and distribution of huge volumes of data, and lack of interoperability with other hospital information systems, most notably Picture Archive and Communications Systems (PACS) based on the DICOM standard.This article proposes an architecture of a Web Pathology PACS fully compliant with DICOM standard communications and data formats. The solution includes a PACS Archive responsible for storing whole-slide imaging data in DICOM WSI format and offers a communication interface based on the most recent DICOM Web services. The second component is a zero-footprint viewer that runs in any web-browser. It consumes data using the PACS archive standard web services. Moreover, it features a tiling engine especially suited to deal with the WSI image pyramids. These components were designed with special focus on efficiency and usability. The performance of our system was assessed through a comparative analysis of the state-of-the-art solutions. The results demonstrate that it is possible to have a very competitive solution based on standard workflows.     

A Survey of DICOM Viewer Software to Integrate Clinical Research and Medical Imaging

The digital imaging and communications in medicine (DICOM) protocol is the leading standard for image data management in healthcare. Imaging biomarkers and image-based surrogate endpoints in clinical trials and medical registries require DICOM viewer software with advanced functionality for visualization and interfaces for integration. In this paper, a comprehensive evaluation of 28 DICOM viewers is performed. The evaluation criteria are obtained from application scenarios in clinical research rather than patient care. They include (i) platform, (ii) interface, (iii) support, (iv) two-dimensional (2D), and (v) three-dimensional (3D) viewing. On the average, 4.48 and 1.43 of overall 8 2D and 5 3D image viewing criteria are satisfied, respectively. Suitable DICOM interfaces for central viewing in hospitals are provided by GingkoCADx, MIPAV, and OsiriX Lite. The viewers ImageJ, MicroView, MIPAV, and OsiriX Lite offer all included 3D-rendering features for advanced viewing. Interfaces needed for decentral viewing in web-based systems are offered by Oviyam, Weasis, and Xero. Focusing on open source components, MIPAV is the best candidate for 3D imaging as well as DICOM communication. Weasis is superior for workflow optimization in clinical trials. Our evaluation shows that advanced visualization and suitable interfaces can also be found in the open source field and not only in commercial products.     

DICOM for Clinical Research: PACS-Integrated Electronic Data Capture in Multi-Center Trials

Providing surrogate endpoints in clinical trials, medical imaging has become increasingly important in human-centered research. Nowadays, electronic data capture systems (EDCS) are used but binary image data is integrated insufficiently. There exists no structured way, neither to manage digital imaging and communications in medicine (DICOM) data in EDCS nor to interconnect EDCS with picture archiving and communication systems (PACS). Manual detours in the trial workflow yield errors, delays, and costs. In this paper, requirements for a DICOM-based system interconnection of EDCS and research PACS are analysed. Several workflow architectures are compared. Optimized for multi-center trials, we propose an entirely web-based solution integrating EDCS, PACS, and DICOM viewer, which has been implemented using the open source projects OpenClinica, DCM4CHEE, and Weasis, respectively. The EDCS forms the primary access point. EDCS to PACS interchange is integrated seamlessly on the data and the context levels. DICOM data is viewed directly from the electronic case report form (eCRF), while PACS-based management is hidden from the user. Data privacy is ensured by automatic de-identification and re-labelling with study identifiers. Our concept is evaluated on a variety of 13 DICOM modalities and transfer syntaxes. We have implemented the system in an ongoing investigator-initiated trial (IIT), where five centers have recruited 24 patients so far, performing decentralized computed tomography (CT) screening. Using our system, the chief radiologist is reading DICOM data directly from the eCRF. Errors and workflow processing time are reduced. Furthermore, an imaging database is built that may support future research.     

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。     

A Comparison of WebRTC and Conventional Videoconferencing for Synchronized Remote Medical Image Presentation

DICOM viewers must fulfill roles beyond primary diagnostic interpretation, including serving as presentation tools in teaching and multidisciplinary conferences, thereby enabling multiple individuals to review images collaboratively in real time. When in-person gathering is not possible, a variety of solutions have been deployed to maintain the ability for spatially separated users to view medical images simultaneously. These approaches differ in their backend architectures, utilization of application-specific optimizations, and ultimately in their end user satisfaction. In this work, we systematically compare the performance of conventional screensharing using a videoconferencing application with that of a custom, synchronized DICOM viewer linked using Web Real Time Communications (WebRTC) technology. We find superior performance for the WebRTC method with regard to image quality and latency across a range of simulated adverse network conditions, and we show how increasing the number of conference participants differentially affects the bandwidth requirements of the two viewing solutions. In addition, we compare these two approaches in a real-world teaching scenario and gather the feedback of trainee and faculty radiologists, who we found to favor the WebRTC method for its decreased latency, improved image quality, ease of setup, and overall experience. Ultimately, our results demonstrate the value of application-specific solutions for the remote synchronized viewing of medical imaging, which, given the recent increase in reliance on remote collaboration, may constitute a significant consideration for future enterprise viewer procurement decisions.

     

DICOM Modality Worklist: An essential component in a PACS environment

The development and acceptance of the digital communication in medicine (DICOM) standard has become a basic requirement for the implementation of electronic imaging in radiology. DICOM is now evolving to provide a standard for electronic communication between radiology and other parts of the hospital enterprise. In a completely integrated filmless radiology department, there are 3 core computer systems, the picture archiving and communication system (PACS), the hospital or radiology information system (HIS, RIS), and the acquisition modality. Ideally, each would have bidirectional communication with the other 2 systems. At a minimum, a PACS must be able to receive and acknowledge receipt of image and demographic data from the modalities. Similarly, the modalities must be able to send images and demographic data to the PACS. Now that basic DICOM communication protocols for query or retrieval, storage, and print classes have become established through both conformance statements and intervendor testing, there has been an increase in interest in enhancing the functionality of communication between the 3 computers. Historically, demographic data passed to the PACS have been generated manually at the modality despite the existence of the same data on the HIS or RIS. In more current sophisticated implementations, acquisition modalities are able to receive patient and study-related data from the HIS or RIS. DICOM Modality Worklist is the missing electronic link that transfers this critical information between the acquisition modalities and the HIS or RIS. This report describes the concepts, issues, and impact of DICOM Modality Worklist implementation in a PACS environment.     

一种DICOM文件并行传送算法的设计与实现

DICOM文件传送是PACS中非常重要的一类文件操作.本文通过分析DICOM文件传送的基本原理,发现DICOM文件串行传送中有大量时间消耗在网络连接和DICOM连接上.为了尽快完成海量影像文件的DICOM传送任务,本文从两方面改进文件传送算法：一是减少网络和DICOM连接次数,每次连接尽量传送更多的文件;二是通过文件并行传送来成倍增加单位时间内文件传送数量.然后针对PACS中待传送DICOM文件特点,设计一种基于任务划分策略的DICOM文件并行传送算法.该算法采用＂一次DICOM连接传送一类文件＂的传送机制和＂Master-Slave＂结构的集中式动态负载平衡方案.该算法在.NET framework 4框架下实现,测试表明上述算法具有良好的并行性能,且显著提高了DICOM文件传送效率.     

A DICOM document-oriented approach to PACS infrastructure

The need for long-term storage requires the future migration of image data from a PACS to its successor system. This paper considers the cost of such migration. It is proposed that storage of data as “documents” in DICOM Part 10 formats on industrystandard media could reduce the time and cost of data migration relative to on-line DICOM transfer. The relation to present efforts in developing document-oriented electronic patient records is discussed. DICOM Part 10 files are found to be a sufficient representation of image documents, but additional software tools will be needed to reach its full potential. There is a significant cost benefit of the document storage method, but it is one of many factors which must be balanced in the selection of a PACS.     

基于数字化影像归档和通信系统的电子申请单集成系统设计

目的根据DICOM接口协议,设计了电子申请单集成系统,使电子化的申请单在电子病历系统与医学影像归档和通信系统（picture archiving and communication system,PACS）之间能够传输和比对,简化临床业务流程。方法通过接口字典文档,HIS系统和PACS系统共同遵循DICOM协议准则。首先设计基本业务流程,然后运用M程序语言编译接口平台,再按照DICOM准则对接接口字典。结果设计完整的从医生开具医嘱到CR、CT、MRI检查终端设备显示的电子申请单集成接口系统,完成身份比对,医嘱比对及影像检查结果匹配等跨系统业务流程的节点传输流程系统。结论系统设计在PACS系统建设中,对医院影像科内的工作流程进行了重新分析,优化设计包括了自动操作和工作合并以及某些设备的迁移,消除不必要的工作步骤以简化流程,扩展采用遵从DICOM标准的成像设备工作列表（MWL）,使患者的基本信息、检查信息、影像信息、诊断信息、检查结果分发信息在流程中完善和统一。     

New facility picture archiving and communication system implementation strategy

Current challenges facing picture archiving and communication systems (PACS) center around database design and functionality. Workflow issues and folder manager concepts such as autorouting, prefetching, hanging protocols, and hierarchical storage management are driven by a properly designed database that ultimately directly impacts the clinical utility of a PACS. The key issues in PACS database design that enable radiologist-friendly, cost-effective, and datasecure systems will be discussed, including database difficulties of the DICOM standard, HIS/RIS/PACS (hospital information system/radiology information system) connectivity, and database issues in data acquisition, data dissemination, and data display.     

医学图像存档和传输系统打印管理服务功能的实现

打印管理是组成医学图像存档和传输(PACS)系统的重要功能模块，必须按照DICOM标准来设计。本简述DICOM中的传输和打印管理服务的基本内容，对打印管理模块的功能进行了分析，在此基础上介绍了打印管理模块的实现，并列出了用DELPHI实现的程序模块以及实现时需注意的一些具体问题。     

Cybersecurity in PACS and Medical Imaging: an Overview

This article provides an overview on the literature published on the topic of cybersecurity for PACS (Picture Archiving and Communications Systems) and medical imaging. From a practical perspective, PACS specific security measures must be implemented together with the measures applicable to the IT infrastructure as a whole, in order to prevent incidents such as PACS systems exposed to access from the Internet. Therefore, the article first offers an overview of the physical, technical and organizational mitigation measures that are proposed in literature on cybersecurity in healthcare information technology in general, followed by an overview on publications discussing specific cybersecurity topics that apply to PACS and medical imaging and present the “building blocks” for a secure PACS environment available in the literature. These include image de-identification, transport security, the selective encryption of the DICOM (Digital Imaging and Communications in Medicine) header, encrypted DICOM files, digital signatures and watermarking techniques. The article concludes with a discussion of gaps in the body of published literature and a summary.