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Documentation of surgical specimens using digital video technology.

CONTEXT: Digital technology is commonly used for documentation of specimens in anatomic pathology and has been mainly limited to still photographs. Technologic innovations, such as digital video, provide additional, in some cases better, options for documentation. OBJECTIVE: To demonstrate the applicability of digital video to the documentation of surgical specimens. DESIGN: A Canon Elura MC40 digital camcorder was used, and the unedited movies were transferred to a Macintosh PowerBook G4 computer. Both the camcorder and specimens were hand-held during filming. The movies were edited using the software iMovie. Annotations and histologic photographs may be easily incorporated into movies when editing, if desired. RESULTS: The finished movies are best viewed in computers which contain the free program QuickTime Player. Movies may also be incorporated onto DVDs, for viewing in standard DVD players or appropriately equipped computers. The final movies are on average 2 minutes in duration, with a file size between 2 and 400 megabytes, depending on the intended use. Because of file size, distribution is more practical via CD or DVD, but movies may be compressed for distribution through the Internet (e-mail, Web sites) or through internal hospital networks. CONCLUSIONS: Digital video is a practical, easy, and affordable methodology for specimen documentation, permitting a better 3-dimensional understanding of the specimens. Discussions with colleagues, student education, presentation at conferences, and other educational activities can be enhanced with the implementation of digital video technology.

Documentation↗

Implementation aspects of image management, archiving, and communication systems in routine clinical use.

Implementation of a digital imaging network in routine clinical use is a difficult task. Not only the high technical requirements, but especially the complexity of the organization of the diagnostic information flow in a hospital makes commitment essential in PACS implementation. The application of project management with a dedicated project team is a good approach to establish this complex endeavor. The different phases of a project for implementation are initiative, definition, design, preparation, realization, and evaluation and are exemplified by what we learned from the Dutch PACS project.

Radiology Information Systems↗

Acceptance testing of integrated picture archiving and communications systems.

An integrated picture archiving and communication system (PACS) is a large investment in both money and resources. With all of the components and systems contained in the PACS, a methodical set of protocols and procedures must be developed to test all aspects of the PACS within the short time allocated for contract compliance. For the Department of Defense (DoD), acceptance testing (AT) sets the protocols and procedures. Broken down into modules and test procedures that group like components and systems, the AT protocol maximizes the efficiency and thoroughness of testing all aspects of an integrated PACS. A standardized and methodical protocol reduces the probability of functionality or performance limitations being overlooked. The AT protocol allows complete PACS testing within the 30 days allocated by the digital imaging network (DIN)-PACS contract. AT shortcomings identified during the testing phase properly allows for resolution before complete acceptance of the system. This presentation will describe the evolution of the process, the components of the DoD AT protocol, the benefits of the AT process, and its significance to the successful implementation of a PACS. This is a US government work. There are no restrictions on its use.

Computer Systems↗

Virtual management of radiology examinations in the virtual radiology environment using common object request broker architecture services.

In the Department of Defense (DoD), US Army Medical Command is now embarking on an extremely exciting new project--creating a virtual radiology environment (VRE) for the management of radiology examinations. The business of radiology in the military is therefore being reengineered on several fronts by the VRE Project. In the VRE Project, a set of intelligent agent algorithms determine where examinations are to routed for reading bases on a knowledge base of the entire VRE. The set of algorithms, called the Meta-Manager, is hierarchical and uses object-based communications between medical treatment facilities (MTFs) and medical centers that have digital imaging network picture archiving and communications systems (DIN-PACS) networks. The communications is based on use of common object request broker architecture (CORBA) objects and services to send patient demographics and examination images from DIN-PACS networks in the MTFs to the DIN-PACS networks at the medical centers for diagnosis. The Meta-Manager is also responsible for updating the diagnosis at the originating MTF. CORBA services are used to perform secure message communications between DIN-PACS nodes in the VRE network. The Meta-Manager has a fail-safe architecture that allows the master Meta-Manager function to float to regional Meta-Manager sites in case of server failure. A prototype of the CORBA-based Meta-Manager is being developed by the University of Arizona's Computer Engineering Research Laboratory using the unified modeling language (UML) as a design tool. The prototype will implement the main functions described in the Meta-Manager design specification. The results of this project are expected to reengineer the process of radiology in the military and have extensions to commercial radiology environments.

Algorithms↗

Application of the advanced communications technology satellite to teleradiology and real-time compressed ultrasound video telemedicine.

The authors have investigated the application of the NASA Advanced Communications Technology Satellite (ACTS) to teleradiology and telemedicine using the Jet Propulsion Laboratory (JPL)-developed ACTS Mobile Terminal (AMT) uplink. In this experiment, bidirectional 128, 256, and 384 kbps satellite links were established between the ACTS/AMT, the ACTS in geosynchronous orbit, and the downlink terrestrial terminal at JPL. A terrestrial Integrated Digital Services Network (ISDN) link was established from JPL to the University of Washington Department of Radiology to complete the bidirectional connection. Ultrasound video imagery was compressed in real-time using video codecs adhering to the International Telecommunication Union-Telecommunication Standardization Sector (ITU-T) Recommendation H.261. A 16 kbps in-band audio channel was used throughout. A five-point Likert scale was used to evaluate the quality of the compressed ultrasound imagery at the three transmission bandwidths (128, 256, and 384 kbps). The central question involved determination of the bandwidth requirements to provide sufficient spatial and contrast resolution for the remote visualization of fine- and low-contrast objects. The 384 kbps bandwidth resulted in only slight tiling artifact and fuzziness owing to the quantizer step size; however, these motion artifacts were rapidly resolved in time at this bandwidth. These experiments have demonstrated that real-time compressed ultrasound video imagery can be transmitted over multiple ISDN line bandwidth links with sufficient temporal, contrast, and spatial resolution for clinical diagnosis of multiple disease and pathology states to provide subspecialty consultation and educational at a distance.

Humans↗

PACS clinical experience at Georgetown University.

Georgetown University Hospital has been operating an image management and communications system (IMACS or PACS) for 3.5 years. This work was initially funded under the Army Medical Research and Development Command Digital Imaging Network Systems (DINS) project. The system was taken from a research system supporting only radiology tasks to one extended to clinical use, and has been used in clinical work for 3 years. This paper will summarize our PACS clinical experience and will describe the operational features implemented and those still necessary.

Computer Systems↗

PACS clinical experience at Georgetown University.

Georgetown University Hospital has been operating an image management and communications system (IMACS or PACS) for three-and-a-half years. This work was initially funded under the Army Medical Research and Development Command Digital Imaging Network Systems (DINS) project. The system was taken from a research system supporting only radiology tasks to one extended to clinical use, and has been used in clinical work for two-and-a-half years. This paper will summarize our PACS clinical experience and will describe the operational features implemented and those still necessary.

Computer Systems↗

Redesigning courses for the World Wide Web.

The use of computer-based instructional technologies has become almost ubiquitous in education, including health professions education. In addition, clinical practice requires the use of digital information, networking, and continued learning. Faculty, students, and clinicians must be prepared to use computer-based technologies and telecommunications. Many faculty members in the health professions need assistance with the transfer of traditional (campus-based) courses or course material to the World Wide Web. This article presents the instructional design and pedagogical aspects of redesigning a traditional campus-based course for the World Wide Web. Specific steps and a template are identified. The development of a virtual community of learners is also discussed as a critical element of on-line teaching and learning.

Computer-Assisted Instruction↗

Cytokines and related receptor-mediated signaling pathways.

Cytokines represent a multi-diverse family of polypeptide regulators; they are of relatively low molecular weight, pharmacologically active proteins that are secreted by one cell for the purpose of altering either its own functions (autocrine effect) or those of adjacent cells (paracrine effect). Cytokines are small, non-enzymatic glycoproteins whose actions are both diverse and overlapping (specificity/redundancy) and may affect diverse and overlapping target cell populations. In many instances, individual cytokines have multiple biological activities. Different cytokines can also have the same activity, which provides for functional redundancy within the inflammatory and immune systems. As biological cofactors that are released by specific cells, cytokines have specific effects on cell-cell interaction, communication, and behavior of other cells. As a result, it is infrequent that loss or neutralization of one cytokine will markedly interfere with either of these systems. The biological effect of one cytokine is often modified or augmented by another. Because an inter-digitating, redundant network of cytokines is involved in the production of most biological effects, both under physiologic and pathologic conditions, it usually requires more than a single defect in the network to alter drastically the outcome of the process. This fact therefore may have crucial significance in the development of therapeutic strategies for bio-pharmacologic intervention in cytokine-mediated inflammatory processes and infections.

Animals↗

Diagnostic accuracy of an international static-imaging telepathology consultation service.

Static-image and dynamic- (real-time) image telepathology are competing technologies. Although some studies suggest that the diagnostic accuracy of the dynamic-image telepathology approaches the accuracy of light microscopy, few reports have documented the diagnostic accuracy of static-image telepathology as used in the setting of an actual surgical pathology consultation practice. We report the results of an analysis of 171 telepathology consultation cases submitted to the Arizona-International Telemedicine Network (AITN). Digital images were submitted by pathologists from six participating institutions in Arizona, Mexico, and China. Telepathologists could render a telepathology diagnosis (TP) or defer rendering a diagnosis to obtain additional video images, glass slides for detailed analysis, or to obtain tissue blocks for special studies such as immunohistochemistry. The telepathologists rendered diagnoses for 144 cases and deferred 27 cases. Two pathologists retrospectively evaluated-glass slides from each case and rendered a consensus glass slide (GS) "truth" diagnosis. There was 88.2% concordance between TP and GS diagnoses (127 of 144 diagnoses). Concordance of 96.5% was achieved for clinically important diagnoses (139 of 144 diagnoses). Telepathologists deferred making a diagnosis to obtain glass slides for conventional light microscopy in 14 cases (8.1%) and for results of immunohistochemistry studies in 13 cases (7.6%). Thus, correct diagnoses were rendered by static-image telepathology in 127 of 171 cases (74.3%) at the time of telepathology diagnostic sessions. Inappropriate field selection and sampling biases of referring pathologists, as well as a tendency of static-image telepathologists to underestimate the complexity of some cases, may reduce the value of consultations based on the viewing of static images.

Humans↗

Deployable teleradiology and telemedicine for the US military.

The US military has been an effective proponent of digital imaging and teleradiology for the past 15 years. A digital imaging network that can eliminate the use of X-ray film can make the requirements simpler for military medicine. X-ray film requires the storage of new, unexposed films that have a fixed shelf life, and the storage and use of chemicals and water for processing. In some deployed situations, the chemical discharge has to be collected and shipped out of the deployed area. The technology of electronic imaging is therefore intrinsically important to military medicine. In December of 1995, the US government started to deploy 20000 US troops to Bosnia-Herzegovina as part of NATO's peace keeping operation (IFOR). A full complement of medical support facilities was to be established in the Bosnia region and Hungary where the deployment was staged. Primetime III was a project to deploy telemedicine and teleradiology capabilities linking these medical treatment facilities (MTF). The deployment of telemedicine was not the responsibility of our engineering team. This paper deals with the deployable teleradiology (DEPRAD) system that was installed by the ISIS Center at a number of facilities for filmless radiology and teleradiology services.

Evaluation Studies as Topic↗

Medical emergency aid through telematics: design, implementation guidelines and analysis of user requirements for the MERMAID project.

MERMAID is an EU financed telemedicine project with global reach and 24-h, multilingual capability. It aspires to provide a model for the provision of health care services based on the electronic transmission of medical information, via ISDN based videoconferencing. This model will not be limited to medical diagnostics but it will encompass all cases where the actual delivery of health care services involves a patient who is not located where the provider is. Its implementation requires the commissioning of an expensive telecommunications infrastructure and the exploration of a number of solutions. In fact, all categories of telemedical applications (audio and video conferencing, multimedia communications, flat file and image transfer with low, medium and high bandwidth data requirements) are considered while the full range of network choices (digital land lines, cellular/wireless, satellite and broadband) are being tested in terms of cost/performance tradeoffs that are inherent to them and the developmental stage each of these options occupies in their in its life cycle. Finally, out that MERMAID utilises advanced land based line transmission technologies to aid the remote patient by making available the specialist care that is best suited in the particular case.

Computers↗

Telepathology for the biopsy specimens from human allografted kidney: effectiveness and pitfalls.

This study was conducted to examine the validity and accuracy of telepathology for biopsy specimens from allografted kidney. The still video images of paraffin sections were transmitted via a two-way telephone by use of a digitized telephone network, ISDN. The quality of the transmitted images was sufficient for the diagnosis, especially at higher magnification. A total of 37 needle biopsy specimens from the 31 allografted kidneys were presented for consultation and diagnosed by an expert pathologist at Tottori University, until July 2000. The average number of transmitted images was 7.1 (range 3-12). Of the 37 specimens, diagnoses by telepathology agreed well with those made through direct microscopy in the 30 specimens. Insufficient or improper diagnosis was made in four specimens, in which proper and pathognomonic still images were not transmitted. Three cases were not diagnosed by telepathology because of the difficulty in making differential diagnosis. From these results, we concluded that telepathology is useful for transplantation pathology, in spite of limitations in some cases.

Biopsy, Needle↗

[Gynecological ultrasound network: new concepts].

Digital data processing and storage are advancing in many medical settings. Some ultrasound machines process, store and provide images digitally. For many obstetrical and gynecological ultrasound units electronic filing and reporting are essential parts of their documentation. However, patient data are often entered redundantly into the different systems (admission and billing, encoding of diagnoses, medical reports etc.). Bi-directional exchange of textual data is the first step towards successful integration. Additionally, affordable central digital video storage from different sources within a department or hospital will soon become available.

Computer Communication Networks↗

A store-forward ophthalmic telemedicine case report from deployed U. S. Army forces in Kuwait.

This telemedicine test was developed to determine the relative ease with which an off-the-shelf ophthalmic telemedicine package could be successfully applied from within a remote theatre of operations. The project was conducted at the Camp Doha Health Clinic, located just outside Kuwait City, during the period from April 12(th) through April 23(rd), 1998. The deployed signal unit had contracted for a direct T-1 commercial satellite link (via MCI), which allowed for direct internet connectivity using a PCMCIA network card. Digital images were sent via this connection to 140 e-mail sites throughout the world, including an unsolicited image to each of 134 Army optometry officers for their review, analysis, and diagnosis. Return responses to this unsolicited survey were 53 out of 134, for a 39.7% response rate. Half of the respondents were able to view the image with ease and clarity, rendering an accurate clinical diagnosis. The other half of the respondents either did not have the software to display an image on their clinical desktop PC, or did not know how to use their provided software. This project clearly indicates that an off-the-shelf ophthalmic digital system can be successfully used from a remote deployed site. However, the consulting clinicians require up-to-date training, and their computer packages should have as wide a capability base as possible.

Humans↗

Deployable teleradiology: Bosnia and beyond.

The United States military has been an effective proponent of digital imaging and teleradiology for the past 15 years [1]. A digital imaging network that eliminates the use of x-ray film makes military medicine requirements simpler. X-ray film requirements include storage of new, unexposed films, storage and use of chemicals and water for processing, and disposal of chemicals. In some deployed situations, the chemical discharge needs to be collected and shipped out of the area. Therefore, the ability to implement electronic imaging and eliminate or greatly reduce the dependence on film, chemicals, and water are intrinsically important to military medicine. In December 1995, the United States government began deployment of 20,000 United States troops to Bosnia-Herzegovina as part of NATO's peacekeeping implementation force (IFOR) operation. A full complement of military medical support facilities was established in Bosnia. An army base in Hungary was the location from which the deployment was staged. The project to deploy telemedicine and teleradiology capabilities to the medical treatment facilities (MTF) in Bosnia and Hungary became known as PrimeTime III [2]. This paper deals with the deployable teleradiology (DEPRAD) system that was installed by the Imaging Science and Information Systems (ISIS) Center, Department of Radiology, Georgetown Medical Center, Washington, DC, at a number of facilities to implement filmless radiology and teleradiology services in support of PrimeTime III.

Bosnia and Herzegovina↗

Relief for maritime medical emergencies through telematics.

MERMAID is a European Union (EU)-financed maritime telemedicine project with global reach and 24-h multilingual capability, so as to serve multinational crews working in the isolation of the world's oceans. It provides a model for the provision of healthcare services based on the electronic transmission of medical information via ISDN-based video conferencing. This model is not limited to medical diagnostics, but it encompasses all cases in which the actual delivery of healthcare services involves a patient who is not located where the provider is. Its implementation requires the commissioning of an extensive telecommunications infrastructure that includes both satellite transmission for ship to shore communication and an extensive ground-based network for summoning expert medical help from around the world so as to meet the project's multilinguality requirements and, therefore, the exploration of a number of solutions. In fact, all categories of telemedical applications (audio and video conferencing, multimedia communications, flat file and image transfer with low-, medium-, and high-bandwidth data requirements) are considered, while the full range of network choices (digital land lines, cellular/wireless, satellite, and broadband) are being tested in terms of cost/performance tradeoffs that are inherent to them and the developmental stage each of these options occupies in their lifecycle. Finally, out of that, MERMAID utilizes advanced land-based line transmission technologies to aid the remote patient by making available the specialist care that is best suited in the particular case.

Emergency Treatment↗