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PubMed1992

Expediting prior approval and containing third-party costs for dental care.

Dental insurance carriers frequently require referral of radiographs for determination of prior approval. Radiographs are also often used for obtaining expert opinions before finalizing diagnoses and establishing treatment plans. Traditionally, such referrals have been carried out using the original or duplicate films transmitted through the postal system. Studies concerning alternative communication media for data transmission are presented, namely, the use of switched-digital telephone lines and of electronic mail networks.

Computer Communication Networks↗

PubMed1996

Experimental telemedicine in orthopaedics.

There have so far been few telemedical applications in orthopaedics. This experiment involved clinicians in three different locations, two in Helsinki and the third in Tampere, consulting one another simultaneously. We used an ATM network to transfer X-ray pictures, digitized by a 12-bit CCD scanner and archived in a central image server. The consultations between the clinicians and the examination of the patient were transmitted by a videoconferencing system using the ISDN. We found that telemedicine offers new possibilities in orthopaedics, for clinical work, for training and for research.

Finland↗

PubMed2000

Disaster drills and continuous medical education using satellite-based Internet.

We designed and evaluated a satellite-based Internet system for use in medical applications. Many experimental telemedicine projects use satellites, but we combined digital satellite communication with an ordinary telephone network to realize an economical countrywide network for emergency medicine and continuous medical education. The system appears to be a useful and practical technology for daily clinical activities.

Disaster Planning↗

PubMed2005

Virtual microscopy:applications to hematology.

Virtual microscopy is the simulation of microscopy over a computer network. A virtual slide is a giant digital image file of a glass slide that can be displayed, panned, zoomed, and focused in a virtual slide viewer on a computer screen. Virtual slides represent a revolutionary advance over glass slides. They are easy to file, store, retrieve, annotate, and mark and can be preserved indefinitely. Furthermore, they are easy to duplicate and distribute and can be integrated into electronic patient records. Large virtual slides can be readily transmitted to users over a standard broadband connection. With the recent introduction of viewers that can focus virtual slides, virtual microscopy can simulate all the functions of real microscopy. Virtual microscopy has significant advantages over real microscopy in education and in proficiency testing. In education, virtual microscopy enables "anytime, anywhere" learning and has been favorably received by students and teachers. In proficiency surveys, all users view the same image, virtual slides are easy to distribute, and the slides do not deteriorate. Potential applications for hematology proficiency surveys include blood and bone marrow morphology, differential cell counts, cytochemistry and immunocytochemistry, detection of malarial parasites, and other tests. Virtual microscopy enables proficiency surveys of critical clinical parameters, such as the bone marrow blast count, and implementation of "locate and identify" exercises. It is conceivable that with the next generation of technological developments, virtual microscopy can be extended to diagnostic applications. Important goals are to minimize slide file size without loss of relevant detail, to establish diagnostic equivalence, and to automate virtual slide capture with high throughput for integration into laboratory information systems. Key factors that will drive implementation include user-friendliness, cost, data storage requirements, and throughput speed. Implementation may have constructive effects on teaching and learning, the peer-to-peer consultative process, and diagnostic accuracy and performance.

Hematology↗

PubMed1997

[Use of palm-top computers within the scope of medical data collection and quality assurance].

Computerisation of the medical profession is advancing particularly as the reform of the German medical system is underway and efforts to maintain high quality standards are being made. More and more clinics and private physicians store the data, which they collect in their daily work, in digital form and exchange it via electronic networks. But lacking overall concepts and resistance from monopolistic structures prevent the introduction of innovative technologies, which would allow convenient data collection "on the fly", patterned after proven work routines. This could lead to a real relief from the daily paper work. New approaches using available hard- and software developed abroad demonstrate medical palmtop computing on the Apple Newton.

Data Collection↗

PubMed1997

[Digital radiology].

Digital radiology is the integration of established and new digital imaging modalities into a system which enables the filmless communication of radiological information. It is becoming an indispensable tool in daily medical practice, and yields improved, faster medical communication, reduces the patient's dose and saves 307 307 archivation costs. Some knowledge of the inherent features of digital images and some open-mindedness for a change in viewing and workflow habits is necessary to make full profit of these possibilities. This paper describes digital radiography and the aspects of radiological networking based on 5 years experience with one of the very first filmless radiology departments worldwide.

Computer Communication Networks↗

PubMed1987

Meridian-like networks of internal organs, corresponding to traditional Chinese 12 main meridians and their acupuncture points as detected by the "Bi-Digital O-Ring Test imaging method": search for the corresponding internal organ of Western medicine for each meridian--Part I.

The "Bi-Digital O-Ring Test" imaging method has been successfully used not only to outline the internal organs but also malignant tumors as long as identical reference control tissue is available, regardless of whether it comes from the same individual or others, without exposing the patient to undesirable radiation from X-Rays, strong magnetic field or ultra-sound. While imaging the outline of the internal organs the author found that, from the surface of each organ, lines or networks of lines extend to other parts of the body. Such a line closely resembles well-known lines of meridians of major internal organs in Oriental medicine. This meridian-like network of each internal organ can be imaged using a microscopic slide, dessicated tissue or raw tissue of the same internal organ as reference control substance in "Bi-Digital O-Ring Test" imaging method. In previous papers, among meridians of 12 main internal organs in Traditional Chinese Medicine, the author was able to find which meridian corresponds to which internal organ of Western Medicine as in 10 meridians by "Bi-Digital O-Ring Test" imaging with corresponding internal organs as reference control substances, with the exception of "Pericardium Meridian", and "Triple Burner Meridian". In this study we were able to confirm that the "Pericardium Meridian" can be imaged mainly using adrenal gland as a reference control substance and "Triple Burner Meridian" can be imaged by the ovary or adrenal gland in the female and also can be imaged by the testes or adrenal gland in the male. Thus, the author was able to confirm, for the first time, the corresponding internal organ of Western Medicine for each one of the 12 main meridians. During this study, when actively imaging the meridian-like network, the author found bulging areas of the meridian-like network at specific locations, and found that these bulging areas correspond to specific acupuncture points. The area or average diameter of these acupuncture points often increased in the abnormal area and returned relatively small normal diameter by acupuncture given on certain acupuncture points of the same meridian. Thus, one can find the exact location of the meridian-like network and specific acupuncture points along the network. Therefore, it is now possible to re-evaluate true effects of giving acupuncture on these specific points as well as some of the other classical concepts of acupuncture.

Acupuncture Therapy↗

PubMed2006

Quality control for digital mammography: part II. Recommendations from the ACRIN DMIST trial.

The Digital Mammography Imaging Screening Trial (DMIST), conducted under the auspices of the American College of Radiology Imaging Network (ACRIN), is a clinical trial designed to compare the accuracy of digital versus screen-film mammography in a screening population [E. Pisano et al., ACRIN 6652-Digital vs. Screen-Film Mammography, ACRIN (2001)]. Part I of this work described the Quality Control program developed to ensure consistency and optimal operation of the digital equipment. For many of the tests, there were no failures during the 24 months imaging was performed in DMIST. When systems failed, they generally did so suddenly rather than through gradual deterioration of performance. In this part, the utility and effectiveness of those tests are considered. This suggests that after verification of proper operation, routine extensive testing would be of minimal value. A recommended set of tests is presented including additional and improved tests, which we believe meet the intent and spirit of the Mammography Quality Standards Act regulations to ensure that full-field digital mammography systems are functioning correctly, and consistently producing mammograms of excellent image quality.

Breast↗

PubMed2005

Determining the asymmetry of skin lesion with fuzzy borders.

It is highly desirable to identify malignant melanoma, a common cancer, at an early stage. One important clinical feature of this cancer is asymmetrical skin lesions. In this paper, we propose an adaptive fuzzy approach that uses symmetric distance (SD) to measure lesions with fuzzy borders. The use of a number of SD variations and the adoption of a backpropagation neural network enhances the discriminative power of the approach. Digitized images from the Lesion Clinic in Vancouver, Canada, demonstrate the accurate classification of asymmetric lesions at around 80%.

Algorithms↗

PubMed2004

[Telemedicine stroke department network. Introduction of a telemedicine pilot project for integrated stroke management in South Bavaria and analysis of its efficiency].

More than 100 stroke units have been established in Germany. In rural areas, however, acute stroke care needs to be improved. In order to advance clinical stroke therapy, two specialized stroke centers founded a telemedicine network (TEMPiS) among 12 community hospitals in eastern Bavaria. Each network hospital established specialized stroke wards where qualified teams manage acute stroke patients. Twenty-four hours daily, physicians in local hospitals are able to contact the stroke centers via videoconferencing including transmission of digital DICOM data. To study the efficacy of this network, a controlled trial will be performed. Five TEMPiS-network hospitals will be matched with five other hospitals equal in size, catchment area, and diagnostic techniques. For about 1 year, all consecutive stroke cases in the matched study hospitals will be prospectively recorded in a database. Neurological deficits will be quantified on the National Institute of Health Stroke Scale within 24 h after stroke onset. Mortality and institutional care as a combined primary endpoint will be assessed after 3 and 12 months. Furthermore, functional outcome according to the modified Rankin scale, Barthel score, and quality of life will be assessed using a standard telephone interview. Data acquisition started in July 2003, and final results are expected in 2005.

Centralized Hospital Services↗

PubMed1993

Telemicroscopy.

The feasibility of operating an electron microscope from a remote location using a high-speed computer network has been investigated. A 400 kV electron microscope was modified so that most microscope parameters and stage movement (x, y, z and tilt), can be controlled by a local host computer. The host computer also controls acquisition of digital images from the microscope from either a TV or a slow-scan CCD camera. A computer located at a remote site may send commands to the host computer via a fiber optic network to receive digital images and information concerning the status of microscope. Such a system has been demonstrated at the SIGGRAPH 1992 conference in Chicago and the Supercomputing 92 conference in Minneapolis, where we remotely collected three-dimensional image data sets using the electron microscope in San Diego. This approach, referred to as "telemicroscopy", promises to make possible live microscopy teleconferencing and thereby increase the accessibility and effective usage of the limited number of specialized microscopy resources.

Computer Communication Networks↗

PubMed1996

Electronic collaboratories and digital libraries.

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Computer Communication Networks↗

PubMed1996

We are all digital.

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Computer Communication Networks↗

PubMed2003

Digital image processing: a primer for JVIR authors and readers: part 2: digital image acquisition.

This is the second installment of a three-part series on digital image processing intended to prepare authors for online submission of manuscripts. In the first article of the series, we reviewed the fundamentals of digital image architecture. In this article, we describe the ways that an author can import digital images to the computer desktop. We explore the modern imaging network and explain how to import picture archiving and communications systems (PACS) images to the desktop. Options and techniques for producing digital hard copy film are also presented.

Algorithms↗

PubMed2001

Dynamical stability conditions for recurrent neural networks with unsaturating piecewise linear transfer functions.

We establish two conditions that ensure the nondivergence of additive recurrent networks with unsaturating piecewise linear transfer functions, also called linear threshold or semilinear transfer functions. As Hahnloser, Sarpeshkar, Mahowald, Douglas, and Seung (2000) showed, networks of this type can be efficiently built in silicon and exhibit the coexistence of digital selection and analog amplification in a single circuit. To obtain this behavior, the network must be multistable and nondivergent, and our conditions allow determining the regimes where this can be achieved with maximal recurrent amplification. The first condition can be applied to nonsymmetric networks and has a simple interpretation of requiring that the strength of local inhibition match the sum over excitatory weights converging onto a neuron. The second condition is restricted to symmetric networks, but can also take into account the stabilizing effect of nonlocal inhibitory interactions. We demonstrate the application of the conditions on a simple example and the orientation-selectivity model of Ben-Yishai, Lev Bar-Or, and Sompolinsky (1995). We show that the conditions can be used to identify in their model regions of maximal orientation-selective amplification and symmetry breaking.

Animals↗

PubMed1998

Comparison of MPEG digital video with super VHS tape for diagnostic echocardiographic readings.

BACKGROUND: Digital recording of echocardiographic studies is on the clinical horizon. However, full digital capture of complete echocardiographic studies in traditional video format is impractical, given current storage capacity and network bandwidth. To overcome these constraints, we evaluated the diagnostic image quality of digital video by using MPEG (Motion Picture Experts Group) compression. METHODS AND RESULTS: Fifty-eight complete, consecutive studies were recorded simultaneously with the use of MPEG-1 and sVHS videotape. Each matched MPEG and sVHS study pair was reviewed by two from a total of six readers, and findings were recorded with the use of a detailed, computerized reporting tool. Intrareader and interreader discrepancies were characterized as major or minor and analyzed in total and for specific subgroups of findings (left and right ventricular parameters, valvular insufficiency, and left ventricular regional wall motion). Intrareader discrepancies were reviewed by a consensus panel for agreement with either MPEG or sVHS findings. There was an exact concordance between MPEG and sVHS readings in 83% of findings. The majority of discrepancies were minor, with major discrepancies in only 2.7% of findings. There was no difference in the rate of consensus panel agreement with MPEG or sVHS for instances of intrareader discrepancy, either in total or for any subgroup of findings. Interreader discrepancy rates were nearly identical for both MPEG and sVHS. CONCLUSIONS: MPEG-1 digital video is equivalent to sVHS videotape for diagnostic echocardiography. MPEG increases the range of practical options for digital echocardiography and offers, for the first time, the advantages of digital recording in a familiar video format.

Echocardiography↗

PubMed1993

The effect of irreversible image compression on diagnostic accuracy in thoracic imaging.

RATIONALE AND OBJECTIVES: Digital image compression reduces the storage requirements and network traffic on picture archiving and communications systems. Full-frame bit-allocation (FFBA) is an irreversible image-compression method based on the discrete cosine transform that provides for high compression ratios with a high degree of image fidelity. METHODS: One hundred twenty-two posteroanterior chest radiographs were obtained on patients in an ambulatory patient setting, including 30 cases of interstitial lung disease, 45 images containing combinations of lung nodules (N = 37) or mediastinal masses (N = 39), and 47 normal images containing none of the pathology for which we were testing. The images were digitized (nominal 2 K x 2 K x 12-bit resolution), printed on a 35 x 35-cm hard copy format, and compressed at an approximate compression ratio of 20:1. Observer performance tests were conducted with five radiologists using receiver operating characteristics analysis on digitized uncompressed and compressed hard copy images. RESULTS: There were no significant differences between the two display conditions for the detectability of any of the thoracic abnormalities. CONCLUSIONS: Our preliminary results suggest that irreversible image compression at ratios of 20:1 may be acceptable for use in digital thoracic imaging.

Algorithms↗

PubMed2003

A declarative implementation of the DICOM-3 network protocol.

We describe a new design for programs using the Digital Imaging and Communications in Medicine (DICOM) protocol, which we have implemented in a DICOM image storage server and a radiation treatment plan transfer facility for our locally developed radiation treatment planning system, Prism. This design is declarative, representing DICOM as a language for describing messages and sequencing of messages. The coding involved implementing an interpreter for this language. The DICOM protocol specifies messages, message formats, and sequencing. In our design, the specification translates almost directly into computer-readable declarative expressions that closely resemble the relevant tabulated DICOM specifications. The resulting programs are small, simple, and extensible, because most of the details of the DICOM protocol are not coded in the procedural control statements but are in the expressions and state table that the interpreter uses to perform all its functions. This approach provides a way to validate the consistency of a specification and the correctness of the implementation. The same method can be generalized to other such protocols. It may also be used to assist the design of new protocols.

Algorithms↗