We are replacing a weekly ambulatory service by radiologists from a central hospital to a small r... more We are replacing a weekly ambulatory service by radiologists from a central hospital to a small regional clinic. The new procedure involves daily transmission of digital images, reading the images centrally at a multi-screen workstation, and digital back transmission of dictated reports. We have designed new work procedures, and installed equipment for scanning and for diagnostic workstation. Results so far seem to confirm that teleradiology may represent a viable solution for small clinics lacking qualified radiologists.
An unconventional analog-to-digital converter and multiplexer is described. The instrument is bas... more An unconventional analog-to-digital converter and multiplexer is described. The instrument is based on conversion of the analog signals to time intervals between narrow-width pulses by an encoder unit. The coded analog signals may then be transferred on a single line to a decoder unit and/or stored on a single track of an AM magnetic tape recorder for later processing. The signals are digitized in the decoder unit by measuring the time intervals between the pulses by means of a binary counter driven by a 19.8-MHz oscillator. The decoder is directly communicating with the interface of a digital computer, and a software package has been written for the control of data transmission. The performance of the instrument in our version is: eight separate analog inputs, sampling rate 200 Hz, input voltage-1.6 to 1.6 V, resolution capacity 3.2 V/213, noise ~0.1%, signal bandwidth dc to 50 Hz ac.
Since September 1992, Troms Military Hospital (Norway) has been connected to the larger Universit... more Since September 1992, Troms Military Hospital (Norway) has been connected to the larger University Hospital of Tromsø by a teleradiology link transmitting about 6000 examinations annually. In the spring of 1995, the system was upgraded with a digital X-ray unit, thereby almost eliminating the scanning of analog radiographs. This article describes the technical development of the link. The discussion suggests ways of improving the teleradiology link, particularly in terms of integrating the radiology information system (RIS) and picture archiving and communication system (PACS).
The purpose of this study is to explore how wireless transfer of sensor data can be implemented i... more The purpose of this study is to explore how wireless transfer of sensor data can be implemented in existing Electronic Health Record (EHR) systems. Blood glucose data from people with diabetes Type 1 has been selected as the case.As proof of concept, a prototype for sending blood glucose measurements into an EHR system was developed for the DIPS EHR system. For the prototype to be transferable to a general setting, care was taken not to introduce any additional workload for the diabetes nurses or the diabetes Type 1 patients. In the prototype, the transfer of blood glucose data is automatic and invisible to the user, and the data is presented to the nurses within the existing DIPS laboratory module.To determine whether deployment of such a system would present any risks or hazards to patients (medical or financial), a risk analysis was performed. The analysis indicates that storing blood glucose values in the patient's EHR does not represent any significantly increased risks for the diabetes patient.The study shows that existing EHR systems are well suited to receive sensor data. The three main EHR systems in Norwegian hospitals are all supported with application programming interfaces (APIs), enabling external vendors to add modules. These APIs are sufficient to implement modules for receiving sensor data. However, none of the systems currently have commercially available modules for receiving such data.
A load invariant presentation of the heart's ventricular performance has been investigate... more A load invariant presentation of the heart's ventricular performance has been investigated. Flow from the right ventricle of isolated cat hearts was passed through a controlled, variable load. Ventricular pressure and flow were recorded and ventricular volume computed by flow integration. The three-dimensional trajectories of ventricular pressure, ventricular volume and time after onset of contraction all closely followed a single three-dimensional surface, which was denoted as the PVt surface. The PVt surface depends on the inotropic condition of the heart, but is load invariant. It is therefore a measure of the intrinsic ventricular performance. Given the arterial load on the ventricle, it can be applied for predictions of pressure and flow profiles, as well as any parameter related to them.
Using data from an isolated supported cat right ventricle preparation, we investigated the follow... more Using data from an isolated supported cat right ventricle preparation, we investigated the following models or methods for characterising the mechanical function of the ventricle: (1) a pressure generator in series with an internal impedance; (2) a variable elastance in series with an internal, pressure dependent flow resistance; (3) pulse response analyses, theoretically based on the pressure response to a small volume step of short duration; and (4) geometric mapping of the variables pressure and volume as functions of time. We tested the reproductive and predictive strengths of the four models, and found that all methods could reproduce 50% of the observed pressure curves with an RMS error less than 0.2 kPa, and in most cases also gave a close prediction of pressure curves which were not used to establish the respective model parameters. We see this as one reason for the fact that no single ventricular model has yet been universally accepted.
Computer Methods and Programs in Biomedicine, May 1, 1992
In the Nordic countries there are several reasons why teleradiology has been an interesting topic... more In the Nordic countries there are several reasons why teleradiology has been an interesting topic of research during the last years. The distances in rural areas are long, and radiology expert service is not available in every health centre which is able to provide X-rays. Also, the telecommunication network is on a very advanced level in the Nordic countries. The staff is well educated and they are used to operating with computers. This all means that the infrastructure to develop and use systems like teleradiology exists. This paper describes two separate systems developed in Norway and Finland. Their development has been in many respects the same. The common hardware and software features, as well as the differences and the clinical experiences, are discussed in this paper.
American Journal of Physiology-heart and Circulatory Physiology, Feb 1, 1982
Right ventricular performance of isolated supported cat hearts was experimentally characterized b... more Right ventricular performance of isolated supported cat hearts was experimentally characterized by a relationship among ventricular pressure (P), volume (V), and time after onset of systole. This characterization was combined with a hypothetical load network consisting of lumped central and peripheral lung vascular resistances (Rc and Rp), inertance (L), and compliance (C). We calculated ventricular and load pressure, flow, external ventricular work (Wext), static ventricular P-V energy (Wstat), and pump efficiency Q = Wext/Wstat over a broad range of load conditions. Magnitudes of load network variables resulting in a maximum value of Q would define the load impedance matching the ventricle. A practical optimum magnitude of lumped vascular compliance was obtained at C = 150 x 10(-6) g-1 . cm4, above which no substantial change in Q took place. We obtained maximum Q at approximately 4 ml stroke volume (heart rate = 2 Hz) and at characteristic impedance between 0.75 and 1.1 x 10(3)g . cm-1 . s-1. As these values are quite close to those encountered in the intact animal, we conclude that the right ventricular and the pulmonary arterial tree appear to constitute a matched pump-load system.
Several methods for describing the ventricular performance or the ventricular afterload exist in ... more Several methods for describing the ventricular performance or the ventricular afterload exist in the literature. Milnor (1975) has advocated to represent the afterload by the arterial input impedance, as the impedance graph is the most accurate way of representing the arterial system as seen by the ejecting ventricle. More recently, the ventricular performance has been analysed in terms of the variables pressure, volume and time. According to experimental results from research groups including our own, this method gives a description of the ventricular performance which is both accurate and unambiguous. However, it remains to combine these two independent descriptions of the ventricle and the afterload in the purpose of solving the problem of the interaction between the two. This paper demonstrates procedures for obtaining, on a purely computational basis, values during the cardiac cycle of important variables like pressure in the ventricle and at the inlet of the arterial system, ventricular volume, flow, and in principle all variables related to these.
Tidsskrift for Den norske lægeforening, Aug 8, 2022
Svein Aarseth er spesialist i allmennmedisin og i arbeidsmedisin og leder i Rådet for legeetikk. ... more Svein Aarseth er spesialist i allmennmedisin og i arbeidsmedisin og leder i Rådet for legeetikk. Forfa eren har fylt ut ICMJE-skjemaet og oppgir ingen interessekonflikter. Torbjørn Sund er dr.ing., pensjonist og tidligere forsker ved Universitetet i Tromsø og i Telenor. Forfa eren har fylt ut ICMJE-skjemaet og oppgir ingen interessekonflikter. Lil-Sofie Ording Müller er spesialist i radiologi med spesialkompetanse i barneradiologi og muskelskjele-lidelser hos barn og er overlege ved Klinikk for radiologi og nukleaermedisin, Oslo universitetssykehus. Forfa eren har fylt ut ICMJE-skjemaet og oppgir ingen interessekonflikter. Johan Bring er dosent og statistiker ved Statisticon. Forfa eren har fylt ut ICMJE-skjemaet og oppgir ingen interessekonflikter.
Stimulated by the rapid development in ICT, wireless communication and sensor development, patien... more Stimulated by the rapid development in ICT, wireless communication and sensor development, patient care is moving out of the institution and into the personal realm. The move requires that eHealth systems should be tailored to the user, including personalization and adaptation to user context. This paper describes ongoing work to establish a standard for such personalization. The standard builds on the user's preferences and current situation, which together define the current user profile. This profile can then be used by eHealth services and devices to ensure a user experience tailored to each person and situation. The work surveys relevant areas of personalization, like identity management, profile management etc, addressing those aspects of personalization that are specific to eHealth: user capabilities, care provider roles and functions, health related information, and confidentiality measures. ⋆ Work funded by the European Telecommunications Standards Institute with support from the European Commission and the European Free Trade Association.
To investigate whether sliding window adaptive histogram equalization (SWAHE) of digital mammogra... more To investigate whether sliding window adaptive histogram equalization (SWAHE) of digital mammograms improves the detection of simulated calcifications, as compared to images normalized by global histogram equalization (GHE). Direct digital mammograms were obtained from mammary tissue phantoms superimposed with different frames. Each frame was divided into forty squares by a wire mesh, and contained granular calcifications randomly positioned in about 50% of the squares. Three radiologists read the mammograms on a display monitor. They classified their confidence in the presence of microcalcifications in each square on a scale of 1 to 5. Images processed with GHE were first read and used as a reference. In a later session, the same images processed with SWAHE were read. The results were compared using ROC methodology. When the total areas AZ were compared, the results were completely equivocal. When comparing the high-specificity partial ROC area AZ,0.2 below false-positive fraction (FPF) 0.20, two of the three observers performed best with the images processed with SWAHE. The difference was not statistically significant. When the reader's confidence threshold in malignancy is set at a high level, increasing the contrast of mammograms with SWAHE may enhance the visibility of microcalcifications without adversely affecting the false-positive rate. When the reader's confidence threshold is set at a low level, the effect of SWAHE is an increase of false positives. Further investigation is needed to confirm the validity of the conclusions.
Telemedicine provides sound and image communication for routine and emergency consultations betwe... more Telemedicine provides sound and image communication for routine and emergency consultations between remote practitioners and centralised specialists. Telemedicine can contribute to constraining costs while ensuring equal access to health care services regardless of location. Experiences from telemedicine and remote teaching in rural Norway are applicable to remote oil installations.
For widespread adoption of eHealth, and to achieve eInclusion and eAccessibility, eHealth systems... more For widespread adoption of eHealth, and to achieve eInclusion and eAccessibility, eHealth systems must be tailored to each individual user's needs and preferences. Many eHealth products and services contain adjustable parameter settings, but they are specific to each product and unrelated to each other. This paper describes ongoing work to establish standards and guidelines for personalization of eHealth systems, taking into account the needs of all users, both clients and caregivers. The standard builds on a generic 'user profile', which stores data about the users, their preferences and their context. This profile can then be used by eHealth services and devices to ensure a user experience tailored to each person. The work surveys relevant areas of personalization, like identity management, profile management etc, addressing in depth those aspects of personalization that are specific to eHealth: User capabilities, care provider roles and functions, health related information, and confidentiality measures.
To investigate whether contrast enhancement by non-interactive, sliding window adaptive histogram... more To investigate whether contrast enhancement by non-interactive, sliding window adaptive histogram equalization (SWAHE) can enhance the image quality of intraoral radiographs in the dental clinic. Three dentists read 22 periapical and 12 bitewing storage phosphor (SP) radiographs. For the periapical readings they graded the quality of the examination with regard to visually locating the root apex. For the bitewing readings they registered all occurrences of approximal caries on a confidence scale. Each reading was first done on an unprocessed radiograph ("single-view"), and then re-done with the image processed with SWAHE displayed beside the unprocessed version ("twin-view"). The processing parameters for SWAHE were the same for all the images. For the periapical examinations, twin-view was judged to raise the image quality for 52% of those cases where the single-view quality was below the maximum. For the bitewing radiographs, there was a change of caries classification (both positive and negative) with twin-view in 19% of the cases, but with only a 3% net increase in the total number of caries registrations. For both examinations interobserver variance was unaffected. Non-interactive SWAHE applied to dental SP radiographs produces a supplemental contrast enhanced image which in twin-view reading improves the image quality of periapical examinations. SWAHE also affects caries diagnosis of bitewing images, and further study using a gold standard is warranted.
The present paper introduces user experience guidelines addressing trust, user interaction (inclu... more The present paper introduces user experience guidelines addressing trust, user interaction (including usability and accessibility) and service aspects applicable to the research, design, development and deployment of telecare services. The work, co-funded by the European Commission and EFTA, is performed in ETSI and is entering its final phase of development. An ETSI Guide with the above title will be published
Trials with telemedicine started with the advent of television in the 1930s. Now, 60 years later,... more Trials with telemedicine started with the advent of television in the 1930s. Now, 60 years later, high-quality videoconferences can be run on desktop computers, and in western Europe and North America, high-speed Integrated Services Digital Network (ISDN) telephony suitable for multimedia is gaining ground. The figure shows a prototype conference system combining video, audio, and stored magnetic resonance images for endoscopic consultation. However, as Grigsby points out, the medical profession is hesitant. He estimates that at the beginning of 1995 there were only about 25-30 active telemedicine programs in the USA excluding teleradiology, with an additional 40-50 systems in various stages of development. In western Europe, the corresponding figure is only slightly higher. To increase the use of telemedicine, many governments and funding bodies have initiated research programmes, and a notable event this year was the start of one such programme "Telematics in Health Care" (European Commission DG XIII; the 4th Framework Telematics Application Programme) to which the European Commission has allocated 135 MEcu for 1995-99. Quite a lot of this money will be spent on telemedicine. In contrast, teleradiology is widespread, and even a commercial success. Several private practices in the USA now offer teleradiology services, the largest being Teleradiology Associates with about 25 000 cases projected for 1995 (Forsberg D, personal communication). Teleradiology may proliferate even more as the quality of screen-reading catches up with that of film. Using the latest available computer-screen technology, researchers at the Johns Hopkins Medical Institutions recently found no significant difference between the accuracy of interpretation on film and on screen of radiographs of high diagnostic difficulty (Gitlin J). Comparison of emergency department cases; presented at the 1995 RSNA meeting). With image compression, teleradiology becomes even more accessible. Recent ROC studies indicate that, by use of the Joint Photographers Expert Group algorithm, an eight-fold compression (from 12 bits to 1"5 bits per pixel) has no influence on the diagnosis made by the radiologist (Wong). Teleradiology also profits from the widespread acceptance of the Digital Imaging and Communication in Medicine (DIDCOM) standard for data exchange (Houtchens). In a surprisingly short time, the Internet has profoundly influenced both remote medical education and the distribution of medical information in general. As of July, 1995, there were more than 6 million computers
We are replacing a weekly ambulatory service by radiologists from a central hospital to a small r... more We are replacing a weekly ambulatory service by radiologists from a central hospital to a small regional clinic. The new procedure involves daily transmission of digital images, reading the images centrally at a multi-screen workstation, and digital back transmission of dictated reports. We have designed new work procedures, and installed equipment for scanning and for diagnostic workstation. Results so far seem to confirm that teleradiology may represent a viable solution for small clinics lacking qualified radiologists.
An unconventional analog-to-digital converter and multiplexer is described. The instrument is bas... more An unconventional analog-to-digital converter and multiplexer is described. The instrument is based on conversion of the analog signals to time intervals between narrow-width pulses by an encoder unit. The coded analog signals may then be transferred on a single line to a decoder unit and/or stored on a single track of an AM magnetic tape recorder for later processing. The signals are digitized in the decoder unit by measuring the time intervals between the pulses by means of a binary counter driven by a 19.8-MHz oscillator. The decoder is directly communicating with the interface of a digital computer, and a software package has been written for the control of data transmission. The performance of the instrument in our version is: eight separate analog inputs, sampling rate 200 Hz, input voltage-1.6 to 1.6 V, resolution capacity 3.2 V/213, noise ~0.1%, signal bandwidth dc to 50 Hz ac.
Since September 1992, Troms Military Hospital (Norway) has been connected to the larger Universit... more Since September 1992, Troms Military Hospital (Norway) has been connected to the larger University Hospital of Tromsø by a teleradiology link transmitting about 6000 examinations annually. In the spring of 1995, the system was upgraded with a digital X-ray unit, thereby almost eliminating the scanning of analog radiographs. This article describes the technical development of the link. The discussion suggests ways of improving the teleradiology link, particularly in terms of integrating the radiology information system (RIS) and picture archiving and communication system (PACS).
The purpose of this study is to explore how wireless transfer of sensor data can be implemented i... more The purpose of this study is to explore how wireless transfer of sensor data can be implemented in existing Electronic Health Record (EHR) systems. Blood glucose data from people with diabetes Type 1 has been selected as the case.As proof of concept, a prototype for sending blood glucose measurements into an EHR system was developed for the DIPS EHR system. For the prototype to be transferable to a general setting, care was taken not to introduce any additional workload for the diabetes nurses or the diabetes Type 1 patients. In the prototype, the transfer of blood glucose data is automatic and invisible to the user, and the data is presented to the nurses within the existing DIPS laboratory module.To determine whether deployment of such a system would present any risks or hazards to patients (medical or financial), a risk analysis was performed. The analysis indicates that storing blood glucose values in the patient's EHR does not represent any significantly increased risks for the diabetes patient.The study shows that existing EHR systems are well suited to receive sensor data. The three main EHR systems in Norwegian hospitals are all supported with application programming interfaces (APIs), enabling external vendors to add modules. These APIs are sufficient to implement modules for receiving sensor data. However, none of the systems currently have commercially available modules for receiving such data.
A load invariant presentation of the heart's ventricular performance has been investigate... more A load invariant presentation of the heart's ventricular performance has been investigated. Flow from the right ventricle of isolated cat hearts was passed through a controlled, variable load. Ventricular pressure and flow were recorded and ventricular volume computed by flow integration. The three-dimensional trajectories of ventricular pressure, ventricular volume and time after onset of contraction all closely followed a single three-dimensional surface, which was denoted as the PVt surface. The PVt surface depends on the inotropic condition of the heart, but is load invariant. It is therefore a measure of the intrinsic ventricular performance. Given the arterial load on the ventricle, it can be applied for predictions of pressure and flow profiles, as well as any parameter related to them.
Using data from an isolated supported cat right ventricle preparation, we investigated the follow... more Using data from an isolated supported cat right ventricle preparation, we investigated the following models or methods for characterising the mechanical function of the ventricle: (1) a pressure generator in series with an internal impedance; (2) a variable elastance in series with an internal, pressure dependent flow resistance; (3) pulse response analyses, theoretically based on the pressure response to a small volume step of short duration; and (4) geometric mapping of the variables pressure and volume as functions of time. We tested the reproductive and predictive strengths of the four models, and found that all methods could reproduce 50% of the observed pressure curves with an RMS error less than 0.2 kPa, and in most cases also gave a close prediction of pressure curves which were not used to establish the respective model parameters. We see this as one reason for the fact that no single ventricular model has yet been universally accepted.
Computer Methods and Programs in Biomedicine, May 1, 1992
In the Nordic countries there are several reasons why teleradiology has been an interesting topic... more In the Nordic countries there are several reasons why teleradiology has been an interesting topic of research during the last years. The distances in rural areas are long, and radiology expert service is not available in every health centre which is able to provide X-rays. Also, the telecommunication network is on a very advanced level in the Nordic countries. The staff is well educated and they are used to operating with computers. This all means that the infrastructure to develop and use systems like teleradiology exists. This paper describes two separate systems developed in Norway and Finland. Their development has been in many respects the same. The common hardware and software features, as well as the differences and the clinical experiences, are discussed in this paper.
American Journal of Physiology-heart and Circulatory Physiology, Feb 1, 1982
Right ventricular performance of isolated supported cat hearts was experimentally characterized b... more Right ventricular performance of isolated supported cat hearts was experimentally characterized by a relationship among ventricular pressure (P), volume (V), and time after onset of systole. This characterization was combined with a hypothetical load network consisting of lumped central and peripheral lung vascular resistances (Rc and Rp), inertance (L), and compliance (C). We calculated ventricular and load pressure, flow, external ventricular work (Wext), static ventricular P-V energy (Wstat), and pump efficiency Q = Wext/Wstat over a broad range of load conditions. Magnitudes of load network variables resulting in a maximum value of Q would define the load impedance matching the ventricle. A practical optimum magnitude of lumped vascular compliance was obtained at C = 150 x 10(-6) g-1 . cm4, above which no substantial change in Q took place. We obtained maximum Q at approximately 4 ml stroke volume (heart rate = 2 Hz) and at characteristic impedance between 0.75 and 1.1 x 10(3)g . cm-1 . s-1. As these values are quite close to those encountered in the intact animal, we conclude that the right ventricular and the pulmonary arterial tree appear to constitute a matched pump-load system.
Several methods for describing the ventricular performance or the ventricular afterload exist in ... more Several methods for describing the ventricular performance or the ventricular afterload exist in the literature. Milnor (1975) has advocated to represent the afterload by the arterial input impedance, as the impedance graph is the most accurate way of representing the arterial system as seen by the ejecting ventricle. More recently, the ventricular performance has been analysed in terms of the variables pressure, volume and time. According to experimental results from research groups including our own, this method gives a description of the ventricular performance which is both accurate and unambiguous. However, it remains to combine these two independent descriptions of the ventricle and the afterload in the purpose of solving the problem of the interaction between the two. This paper demonstrates procedures for obtaining, on a purely computational basis, values during the cardiac cycle of important variables like pressure in the ventricle and at the inlet of the arterial system, ventricular volume, flow, and in principle all variables related to these.
Tidsskrift for Den norske lægeforening, Aug 8, 2022
Svein Aarseth er spesialist i allmennmedisin og i arbeidsmedisin og leder i Rådet for legeetikk. ... more Svein Aarseth er spesialist i allmennmedisin og i arbeidsmedisin og leder i Rådet for legeetikk. Forfa eren har fylt ut ICMJE-skjemaet og oppgir ingen interessekonflikter. Torbjørn Sund er dr.ing., pensjonist og tidligere forsker ved Universitetet i Tromsø og i Telenor. Forfa eren har fylt ut ICMJE-skjemaet og oppgir ingen interessekonflikter. Lil-Sofie Ording Müller er spesialist i radiologi med spesialkompetanse i barneradiologi og muskelskjele-lidelser hos barn og er overlege ved Klinikk for radiologi og nukleaermedisin, Oslo universitetssykehus. Forfa eren har fylt ut ICMJE-skjemaet og oppgir ingen interessekonflikter. Johan Bring er dosent og statistiker ved Statisticon. Forfa eren har fylt ut ICMJE-skjemaet og oppgir ingen interessekonflikter.
Stimulated by the rapid development in ICT, wireless communication and sensor development, patien... more Stimulated by the rapid development in ICT, wireless communication and sensor development, patient care is moving out of the institution and into the personal realm. The move requires that eHealth systems should be tailored to the user, including personalization and adaptation to user context. This paper describes ongoing work to establish a standard for such personalization. The standard builds on the user's preferences and current situation, which together define the current user profile. This profile can then be used by eHealth services and devices to ensure a user experience tailored to each person and situation. The work surveys relevant areas of personalization, like identity management, profile management etc, addressing those aspects of personalization that are specific to eHealth: user capabilities, care provider roles and functions, health related information, and confidentiality measures. ⋆ Work funded by the European Telecommunications Standards Institute with support from the European Commission and the European Free Trade Association.
To investigate whether sliding window adaptive histogram equalization (SWAHE) of digital mammogra... more To investigate whether sliding window adaptive histogram equalization (SWAHE) of digital mammograms improves the detection of simulated calcifications, as compared to images normalized by global histogram equalization (GHE). Direct digital mammograms were obtained from mammary tissue phantoms superimposed with different frames. Each frame was divided into forty squares by a wire mesh, and contained granular calcifications randomly positioned in about 50% of the squares. Three radiologists read the mammograms on a display monitor. They classified their confidence in the presence of microcalcifications in each square on a scale of 1 to 5. Images processed with GHE were first read and used as a reference. In a later session, the same images processed with SWAHE were read. The results were compared using ROC methodology. When the total areas AZ were compared, the results were completely equivocal. When comparing the high-specificity partial ROC area AZ,0.2 below false-positive fraction (FPF) 0.20, two of the three observers performed best with the images processed with SWAHE. The difference was not statistically significant. When the reader's confidence threshold in malignancy is set at a high level, increasing the contrast of mammograms with SWAHE may enhance the visibility of microcalcifications without adversely affecting the false-positive rate. When the reader's confidence threshold is set at a low level, the effect of SWAHE is an increase of false positives. Further investigation is needed to confirm the validity of the conclusions.
Telemedicine provides sound and image communication for routine and emergency consultations betwe... more Telemedicine provides sound and image communication for routine and emergency consultations between remote practitioners and centralised specialists. Telemedicine can contribute to constraining costs while ensuring equal access to health care services regardless of location. Experiences from telemedicine and remote teaching in rural Norway are applicable to remote oil installations.
For widespread adoption of eHealth, and to achieve eInclusion and eAccessibility, eHealth systems... more For widespread adoption of eHealth, and to achieve eInclusion and eAccessibility, eHealth systems must be tailored to each individual user's needs and preferences. Many eHealth products and services contain adjustable parameter settings, but they are specific to each product and unrelated to each other. This paper describes ongoing work to establish standards and guidelines for personalization of eHealth systems, taking into account the needs of all users, both clients and caregivers. The standard builds on a generic 'user profile', which stores data about the users, their preferences and their context. This profile can then be used by eHealth services and devices to ensure a user experience tailored to each person. The work surveys relevant areas of personalization, like identity management, profile management etc, addressing in depth those aspects of personalization that are specific to eHealth: User capabilities, care provider roles and functions, health related information, and confidentiality measures.
To investigate whether contrast enhancement by non-interactive, sliding window adaptive histogram... more To investigate whether contrast enhancement by non-interactive, sliding window adaptive histogram equalization (SWAHE) can enhance the image quality of intraoral radiographs in the dental clinic. Three dentists read 22 periapical and 12 bitewing storage phosphor (SP) radiographs. For the periapical readings they graded the quality of the examination with regard to visually locating the root apex. For the bitewing readings they registered all occurrences of approximal caries on a confidence scale. Each reading was first done on an unprocessed radiograph ("single-view"), and then re-done with the image processed with SWAHE displayed beside the unprocessed version ("twin-view"). The processing parameters for SWAHE were the same for all the images. For the periapical examinations, twin-view was judged to raise the image quality for 52% of those cases where the single-view quality was below the maximum. For the bitewing radiographs, there was a change of caries classification (both positive and negative) with twin-view in 19% of the cases, but with only a 3% net increase in the total number of caries registrations. For both examinations interobserver variance was unaffected. Non-interactive SWAHE applied to dental SP radiographs produces a supplemental contrast enhanced image which in twin-view reading improves the image quality of periapical examinations. SWAHE also affects caries diagnosis of bitewing images, and further study using a gold standard is warranted.
The present paper introduces user experience guidelines addressing trust, user interaction (inclu... more The present paper introduces user experience guidelines addressing trust, user interaction (including usability and accessibility) and service aspects applicable to the research, design, development and deployment of telecare services. The work, co-funded by the European Commission and EFTA, is performed in ETSI and is entering its final phase of development. An ETSI Guide with the above title will be published
Trials with telemedicine started with the advent of television in the 1930s. Now, 60 years later,... more Trials with telemedicine started with the advent of television in the 1930s. Now, 60 years later, high-quality videoconferences can be run on desktop computers, and in western Europe and North America, high-speed Integrated Services Digital Network (ISDN) telephony suitable for multimedia is gaining ground. The figure shows a prototype conference system combining video, audio, and stored magnetic resonance images for endoscopic consultation. However, as Grigsby points out, the medical profession is hesitant. He estimates that at the beginning of 1995 there were only about 25-30 active telemedicine programs in the USA excluding teleradiology, with an additional 40-50 systems in various stages of development. In western Europe, the corresponding figure is only slightly higher. To increase the use of telemedicine, many governments and funding bodies have initiated research programmes, and a notable event this year was the start of one such programme "Telematics in Health Care" (European Commission DG XIII; the 4th Framework Telematics Application Programme) to which the European Commission has allocated 135 MEcu for 1995-99. Quite a lot of this money will be spent on telemedicine. In contrast, teleradiology is widespread, and even a commercial success. Several private practices in the USA now offer teleradiology services, the largest being Teleradiology Associates with about 25 000 cases projected for 1995 (Forsberg D, personal communication). Teleradiology may proliferate even more as the quality of screen-reading catches up with that of film. Using the latest available computer-screen technology, researchers at the Johns Hopkins Medical Institutions recently found no significant difference between the accuracy of interpretation on film and on screen of radiographs of high diagnostic difficulty (Gitlin J). Comparison of emergency department cases; presented at the 1995 RSNA meeting). With image compression, teleradiology becomes even more accessible. Recent ROC studies indicate that, by use of the Joint Photographers Expert Group algorithm, an eight-fold compression (from 12 bits to 1"5 bits per pixel) has no influence on the diagnosis made by the radiologist (Wong). Teleradiology also profits from the widespread acceptance of the Digital Imaging and Communication in Medicine (DIDCOM) standard for data exchange (Houtchens). In a surprisingly short time, the Internet has profoundly influenced both remote medical education and the distribution of medical information in general. As of July, 1995, there were more than 6 million computers
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