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PubMed1999

PACS: the second time around.

Conquest Hospital was a Picture Archiving and Communication Systems development site, designed to inform the specification of low cost systems and to provide information on benefits and drawbacks. The American College of Radiologists/National Electrical Manufacturers Association 2.0 protocol was used for image management. The Regional Health Authority sponsored the system, initially installed in mid 1992. It used a high-speed dedicated optical fibre distributed data interface network and for teleradiology an Integrated Services Digital Network solution. Image and other data were captured and archived satisfactorily. Image reporting folders were manually constructed and sent to reporting viewstations. Radiologists were able to directly request 'ad hoc' images from archive. The reporting function of the associated but unlinked radiology information system was satisfactory. Identification was made of data transfer, ergonomic, single point of failure and many other issues. These informed re-specification and the commercial approach for a Digital Images Communication in Medicine/Hyper Text Mark-up Language Picture Archiving and Communication System, the first stages of which have been whole hospital re-networking, Intranet introduction, installation of new Computed Radiography/Fluorography and Computed Tomography/Magnetic Resonance Imaging segments and a new Radiology Information System. The Picture Archiving and Communication System is now seen as part of a full Electronic Patient Record system. Networking and provision of high quality Personal Computer hardware for data review are seen as a corporate responsibility and a hospital overhead, no longer borne by individual projects. Our present work is synergistic with the procurement of a new Clinical Information System and the further development of the hospital Intranet.

Computer Communication Networks↗

PubMed1997

Highlights of the Digital Imaging Network-Picture Archiving and Communications System Project.

The Department of Defense issued its requirements for a Digital imaging Network-Picture Archiving and Communications System (DIN-PACS) in a Request for Proposals to industry in January, 1997. The DIN-PACS shall be an open systems network of digital devices designed for the effective acquisition, transmission, display and management of diagnostic imaging studies. This network is primarily based on two international standards, Digital imaging and Communications in Medicine (DICOM) and Health Level 7 (HL7). The DIN-PACS is required to communicate in a bidirectional manner with the Department of Defense standard hospital information system called the Composite Health Care System (CHCS) through an HL7 compliant interface. The DIN-PACS model and its published specifications stress functionality and performance rather than system architecture to allow industry to propose optimal approaches for implementation. This paper discusses the functional requirements of the DIN-PACS in terms of its internal operations as well as its communication with external systems and components. This is a US government work. There are no restrictions on its use.

Diagnostic Imaging↗

PubMed1998

Effect of ISDN bandwidth on image quality for telemedicine transmission of obstetric ultrasonography.

OBJECTIVE: To evaluate objectively the effect of different bandwidths on the ability to interpret obstetric ultrasound scans transmitted live over a commercial telephone network. MATERIALS AND METHODS: An integrated services digital network (ISDN) was established from three satellite offices to our central prenatal diagnostic center. In the first half of the study, the network was based on four ISDN channels transmitting at a bandwidth of 256 kbits per second (kbps), while in the second half of the study, this was increased to six ISDN channels transmitting at 384 kbps. A physician trained in obstetric ultrasonography provided an interpretation of fetal anatomy using a live, real-time telemedicine link. A scoring system consisting of 33 anatomic items was used to evaluate image quality objectively. The number of transmissions complicated by motion artifact was also recorded. RESULTS: One hundred patients had a fetal anatomy survey performed using the 256 kbps system, and these interpretations were compared with those from another group of 100 patients who were examined using the 384 kbps system. Although the visibility of the 33 anatomic items was similar using the two systems, significantly more examinations at 256 kbps were complicated by motion artifact (12% vs. 3%; P = 0.02). CONCLUSIONS: Remote sonographic viewing of fetal anatomy was adequate using both 256 and 384 kbps systems, although motion artifact was significantly more likely to occur using the slower system. This problem may affect the ability of the lower-bandwidth system to allow optimal detection when fetal anomalies are present.

Artifacts↗

PubMed1990

Enhancement and compression of digital chest radiographs.

The application of digital technologies to chest radiography holds the promise of routine application of image processing techniques to effect image enhancement. Because of their inherent spatial resolution, however, digital chest images impose severe constraints on data storage devices. Compression of these images will relax such constraints and facilitate image transmission on a digital network. We evaluated an algorithm for enhancing digital chest images that has allowed significant data compression while improving the diagnostic quality of the image. This algorithm is based on the photographic technique of unsharp masking. Image quality was measured with respect to the task of tumor detection and compression ratios as high as 2:1 were achieved. This compression can be supplemented by irreversible methods.

Algorithms↗

PubMed1995

[High-resolution teleradiology system based on ISDN and small computer].

A high-speed, high-resolution teleradiology system based on the Integrated Services Digital Network (ISDN) is described. The LAN at Saku Central Hospital and the Radiological Department at Shinshu University Hospital (60 km) are interfaced to a Macintosh computer with an image digitizer, interactive display, and network interface. The transmission time for a digitized high-resolution radiographic image with 4.39 megabytes was 358 seconds using a 128 kbps (kilobit-per-second) channel (B1 + B2), and the mean transmission rate was 98.1 kbps. Teleradiology conference is also available using this system. Radiologists can observe the same high-resolution images on the CRT screen simultaneously at two different remote hospitals, indicating a point of interest on the image by means of a mouse cursor. Graphical data of interest to the radiologists are also transmitted and displayed on the CRT.

Computer Communication Networks↗

PubMed1995

Cost effective Internet access and video conferencing for a community cancer network.

Utilizing the ubiquitous personal computer as a platform, and Integrated Services Digital Network (ISDN) communications, cost effective medical information access and consultation can be provided for physicians at geographically remote sites. Two modes of access are provided: information retrieval via the Internet, and medical consultation video conferencing. Internet access provides general medical information such as current treatment options, literature citations, and active clinical trials. During video consultations, radiographic and pathology images, and medical text reports (e.g., history and physical, pathology, radiology, clinical laboratory reports), may be viewed and simultaneously annotated by either video conference participant. Both information access modes have been employed by physicians at community hospitals which are members of the Jefferson Cancer Network, and oncologists at Thomas Jefferson University Hospital. This project has demonstrated the potential cost effectiveness and benefits of this technology.

Computer Communication Networks↗

PubMed1997

Technical dependability of obstetric ultrasound transmission via ISDN.

OBJECTIVE: To evaluate the dependability of a live telemedicine link for the transmission of obstetric ultrasonograms using a commercial telephone network. MATERIALS AND METHODS: We established an integrated services digital network (ISDN), consisting of three dedicated telephone lines from three satellite offices, to our central prenatal diagnostic center. All patients had a sonographic evaluation recorded on videotape by a trained sonographer. A live interactive video telemedicine link was then established, and a perinatologist directed the sonographer through the scan. A report was issued on the basis of the telemedicine examination. The number of calls required to obtain satisfactory real-time images was recorded, as were the reasons for suboptimal transmissions. The first 150 transmissions were excluded from this study. The results in the subsequent 100 patients who agreed to participate were analyzed. RESULTS: We were able to provide obstetric interpretations in all 100 patients scheduled to be examined using the telemedicine link. A single connection was required in 85 cases, two calls in 5 cases, three calls in 8 cases, four calls in 1 case, and five calls in another case. A repeat call was required in 20 cases because of poor image transmission; other repeat calls were caused by failure to connect (5 cases), calls disconnected (2 cases), and no image transmission (2 cases). CONCLUSIONS: The provision of telemedicine services for obstetric ultrasonography in the community is feasible, but the need for repeat connections because of technical failures needs to be incorporated into cost and time analyses in order to provide a measure of the system's efficiency.

Female↗

PubMed1992

The medical libraries of Vietnam--a service in transition.

The medical libraries of Vietnam maintain high profiles within their institutions and are recognized by health care professionals and administrators as an important part of the health care system. Despite the multitude of problems in providing even a minimal level of medical library services, librarians, clinicians, and researchers nevertheless are determined that enhanced services be made available. Currently, services can be described as basic and unsophisticated, yet viable and surprisingly well organized. The lack of hard western currency required to buy materials and the lack of library technology will be major obstacles to improving information services. Vietnam, like many developing nations, is about to enter a period of technological upheaval, which ultimately will result in a transition from the traditional library limited by walls to a national resource that will rely increasingly on electronic access to international knowledge networks. Technology such as CD-ROM, Integrated Services Digital Network (ISDN), and satellite telecommunication networks such as Internet can provide the technical backbone to provide access to remote and widely distributed electronic databases to support the information needs of the health care community. Over the long term, access to such databases likely will be cost-effective, in contrast to the assuredly astronomical cost of building a comparable domestic print collection. The advent of new, low-cost electronic technologies probably will revolutionize health care information services in developing nations. However, for the immediate future, the medical libraries of Vietnam will require ongoing sustained support from the international community, so that minimal levels of resources will be available to support the information needs of the health care community. It is remarkable, and a credit to the determination of Vietnam's librarians that, in a country with a legacy of war, economic deprivation, and international isolation, they have somehow managed to provide a sound basic level of information services for health care professionals.

Communism↗

PubMed1997

Update in digital mammography.

Digital mammography is a rapidly developing technology that has great potential to improve upon and ultimately replace conventional film-screen mammography for the early detection of breast cancer. This article reviews current progress in digital mammographic systems, computer-aided diagnostic programs, and artificial neural networks. Digital mammographic systems are currently in an investigational phase only. Large-scale clinical trials are needed in all areas of digital mammography before this exciting new technology can be implemented outside of research centers.

Artificial Intelligence↗

PubMed1997

Validation of first-trimester telemedicine as an obstetric imaging technology: a feasibility study.

OBJECTIVE: To establish whether first-trimester obstetric ultrasonography interpreted by a live video telemedicine link is comparable to an established videotape review network in a low-risk patient population. METHODS: An integrated services digital network was established from three satellite offices to our central prenatal diagnostic center. All patients had a sonographic evaluation of the uterus, adnexa, and gestational sac recorded onto videotape by a trained sonographer. A live, interactive video telemedicine link was established, and a perinatologist directed the sonographer through the scan. Subsequently, a different perinatologist, blinded to the telemedicine interpretation, reviewed the original videotaped examination. The reports generated from both modalities then were compared by means of a score of 12 sonographic characteristics. RESULTS: The first 100 patients were included. The mean gestational age (+/-standard deviation) was 8.9 +/- 2.3 weeks (range 5.7-14.4), and the mean duration for telemedicine scans was 7.8 +/- 2.9 minutes (range 3.8-20.1). Telemedicine and videotape review scores were the same in 95 cases, and the final diagnosis was identical in 98 cases. This study had 80% power to detect a 10% difference in diagnosis at a significance level of .05. The ability to detect abnormalities was equivalent using both systems. CONCLUSION: The interpretation of first-trimester obstetric ultrasonography using live video telemedicine is equivalent to a system of videotape review. Obstetric telemedicine may prove to be a useful tool for providing sonographic imaging for low-risk obstetric patients.

Feasibility Studies↗

PubMed1994

Telepathology is available for transplantation-pathology: experience in Japan using an integrated, low-cost, and high-quality system.

We examined the validity and accuracy of telepathology service in the histological diagnosis of biopsy specimens from human transplanted kidney and liver. The still video images of paraffin sections were transmitted via a two-way telephone by use of a digitized telephone network (Integrated Service Digital Networks, 64 kbits/sec). The images were displayed on monitors and diagnosed by an expert pathologist at Tottori University. The quality of transmitted still images was sufficient for the diagnosis, especially at higher magnifications. The average number of transmitted images was 6.2 in the kidney cases and 7.4 in the liver cases. The average time taken for examination of a case was 13 min (range 10 to 16 min). Of 12 biopsy specimens from transplanted kidneys, 10 were adequately diagnosed with the system. Sampling errors caused inadequate diagnosis in a case of cyclosporin tubulopathy, the still images of which were not transmitted. An expert pathologist rendered the diagnosis in a case showing mesangial sclerosis, which was later diagnosed as possible recurrent glomerulonephritis through direct microscopy. Biopsy specimens from 10 liver transplants were also tested using archival materials. Although the etiology of hepatitis could not be determined in one case, diagnoses by telepathology well agreed with the reported diagnoses made through direct microscopy. Telepathology may be an effective way to provide on-line consultations in transplantation pathology, especially for transplant teams lacking expert pathologists.

Adolescent↗

PubMed2003

Moving to paperlessness: a case study from a large general practice.

This case study reports the reasons why this large, multi-site general practice decided to move towards paperless practice in late 2001, and describes the progress and lessons learned to date. The principal operational reasons for this decision were problems associated with moving paper medical records between surgeries, and the realisation that resources to improve the computerised medical record could only come from redeploying the time spent handling paper records. A comprehensive plan was put in place to shift toward paperlessness. Motivating and changing working practices for clinical and support staff was as a great a challenge as upgrading the technology. The practice upgraded its computer system, and has installed scanning and automated generation of referral and other letters. The support staff skills have evolved from moving records to scanning documents and coding data. All clinical staff now consult on their computer, and code diagnoses and key clinical data. A networked digital dictation system allows typing to be centralised at one location, with the networking allowing printing at any site. Audit and quality improvement activities have increased, as the output from computer searches increasingly represents the quality of care provided. The implications of this case study are that a committed general practice can achieve a largely paperless environment in approximately two years. The practice is now fit to be part of any move towards integration of records within its local health community, and can demonstrate from its computer records that it meets the quality targets for primary care.

Ambulatory Care Information Systems↗

PubMed2004

Telemedicine for safe and extended use of thrombolysis in stroke: the Telemedic Pilot Project for Integrative Stroke Care (TEMPiS) in Bavaria.

BACKGROUND AND PURPOSE: Systemic thrombolysis represents the only proven therapy for acute ischemic stroke, but safe treatment is reported only in established stroke units. One major goal of the ongoing Telemedic Pilot Project for Integrative Stroke Care (TEMPiS) in Bavaria is to extend the use of tissue plasminogen activator (tPA) treatment in nonurban areas through telemedic support. METHODS: The stroke centers in Munich-Harlaching and in Regensburg established a telestroke network to provide consultations for 12 local hospitals in eastern Bavaria. The telemedic system consists of a digital network that includes a 2-way video conference system and CT/MRI image transfer with a high-speed data transmission up to 2 Mb/s. Each network hospital established specialized stroke wards in which qualified teams treat acute stroke patients. Physicians in these hospitals are able to contact the stroke centers 24 hours per day. RESULTS: A total of 106 systemic thrombolyses were indicated via teleconsultations between February 1, 2003, and April 7, 2004. During the first 12 months, the rate of thrombolyses was 2.1% of all stroke patients. Mean age was 68 years, and median National Institutes of Health Stroke Scale score was 13. Mean delay between onset and hospital admission was 65 minutes, and door-to-needle time was on average 76 minutes, which included 15 minutes for the teleconsultation. Symptomatic hemorrhage occurred in 8.5% of patients, and in-hospital mortality was 10.4%. CONCLUSIONS: The present data suggest that systemic thrombolysis indicated via stroke experts in the setting of teleconsultation exhibits similar complication rates to those reported in the National Institute of Neurological Disorders and Stroke trial. Therefore, tPA treatment is also safe in this context and can be extended to nonurban areas.

Aged↗

PubMed2000

[Multimedia (visual collaboration) brings true nature of human life].

Videoconferencing system, high-quality visual collaboration, is bringing Multimedia into a society. Multimedia, high quality media such as TV broadcast, looks expensive because it requires broadband network with 100-200 Mpbs bandwidth or 3,700 analog telephone lines. However, thanks to the existing digital-line called N-ISDN (Narrow Integrated Service Digital Network) and PictureTel's audio/video compression technologies, it becomes far less expensive. N-ISDN provides 128 Kbps bandwidth, over twice wider than analog line. PictureTel's technology instantly compress audio/video signal into 1/1,000 in size. This means, with ISDN and PictureTel technology. Multimedia is materialized over even single ISDN line. This will allow doctor to remotely meet face-to-face with a medical specialist or patients to interview, conduct physical examinations, review records, and prescribe treatments. Bonding multiple ISDN lines will further improve video quality that enables remote surgery. Surgeon can perform an operation on internal organ by projecting motion video from Endoscope's CCD camera to large display monitor. Also, PictureTel provides advanced technologies of eliminating background noise generated by surgical knives or scalpels during surgery. This will allow sound of the breath or heartbeat be clearly transmitted to the remote site. Thus, Multimedia eliminates the barrier of distance, enabling people to be just at home, to be anywhere in the world, to undergo up-to-date medical treatment by expertise. This will reduce medical cost and allow people to live in the suburbs, in less pollution, closer to the nature. People will foster more open and collaborative environment by participating in local activities. Such community-oriented life-style will atone for mass consumption, materialistic economy in the past, then bring true happiness and welfare into our life after all.

Endoscopy↗

PubMed1998

Local health care system utilizing the LPG (liquid propane gas) network.

JAC's LPG monitoring network system is mainly provided in mountain villages. However, by using this system, it will be possible to start a Digital Network Program for the Elderly while maintaining superior economic feasibility and public benefit using existing information infrastructures. This project also has the capabilities for the creation of a fire/disaster monitoring system, as well as a health care system by using conventional LPG monitoring systems. Telemedicine is an option for the future, as well, by connecting medical equipment and a tele-conferencing system.

Aged↗

PubMed1996

[Could C- and D-network mobile phones endanger patients with pacemakers?].

OBJECTIVE: To investigate prospectively the extent of potentially harmful interference of cardiac pacemakers by mobile phones in the C (analog) and D (digital) networks in use in Germany. PATIENTS AND METHODS: 104 patients (54 men, 50 women; mean age 75.8 [40-100] years) with 58 different implanted pacemaker models (43 one-chamber and 15 two-chamber systems) underwent uniform tests at various functional states with three different telephones (D1 portable 8 Watt, D1 Handy model 2 Watt, C Handy model 0.5 Watt). The distances between telephone aerial and pacemaker, as well as reception sensitivity and polarity of the pacemaker were varied. All tests were done during continuous ECG monitoring. RESULTS: 28 different pacemaker types (48.3%) in 43 patients (41.3%) showed interference in the form of pacemaker inhibition and switching to interference frequencies as well as triggering of pacemaker-mediated tachycardias in the DDD mode, as well as in the temperature-regulated frequency-adaptive function. D portables influenced pacemaker function more often and at greater distance than the D Handy model, which was little different from the c network hand phone. Reduction in pacemaker sensitivity as well as switching to bipolar reception only partly eliminated the interference. CONCLUSIONS: Patients with implanted pacemakers should if possible not use mobile phones in the C and D networks. Individual testing with suitable programming of pacemaker sensitivity and polarity can reduce the risk of interference.

Aged↗

PubMed2001

A Java-based teleradiology system to provide services over a heterogeneous network.

This paper describes a teleradiology system developed to provide services over a heterogeneous networks environment. The system can transfer radiology images and provide real-time consultations and diagnostics over the telephone, Integrated Service Digital Network (ISDN), as well as a generic hospital network. The network incorporates Ethernet Local Area Network (LAN), ATM switches, and an IP router. The Java Language is used in developing this system. This teleradiology system is flexible, effective, and provides for high performance for end users. The system has been tested over all above networks and the results have shown that the system is robust and efficient.

Computer Communication Networks↗

PubMed2000

[Audiovisual telecommunication by multimedia technology in HNO medicine. ISDN--internet--ATM].

Telemedicine includes all medical activities in diagnosis, therapeutics, or social medicine undertaken by means of an electronic transfer medium, enabling the transmission of visual and acoustic information over long distances to doctors not personally present at the place of the requested consultation. Most experience with telemedicine applications has been gained in the field of diagnosis (teleconsultation, teleradiology, telepathology) and is expanding to quality control and quality assurance. Decisive for each form of application is its availability, practicability, cost, safety, and especially quality of audiovisual transmission. For telesurgical applications, particularly the use of minimally invasive techniques in otorhinolaryngology, head, and neck surgery, the high quality transmission of audiovisual data in real time is necessary. Rapid expansion and further developments in transmission technologies and networks in the last decade have created several technologies with increased quality and costs. In this paper, we tested different transmission media for audiovisual telecommunication--integrated services digital network (ISDN), Internet, and asynchronous transfer mode (ATM)--using real time video transmission of typical operations in otorhinolaryngology. Their applications, costs, and future perspectives are discussed.

Germany↗