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At least 127 records · Page 7Linked to original sources

PubMed2002

Telemedicine for cardiac surgery candidates.

BACKGROUND: Cardiac surgery is generally well or over-represented in many Western countries. Since the southern part of Switzerland relies on 300 km distance centers for cardiac surgery, we started a project of telemedicine for the distant evaluation of cardiac surgery candidates. We report our experience of the results of the diagnosis made by telemedicine and by direct scrutiny of coronary angiograms. METHODS: Coronary angiography was performed at the distant hospital by an invasive cardiology team. Teletransmission of images was performed using three Integrated Service Digital Network (ISDN) lines by direct transmission of recent recording. A total of 98 cases were reviewed (87 aorto-coronary bypass candidates, seven valvular and four congenital heart disease). We further performed a prospective blinded comparison of 47 consecutive cases with severe coronary artery disease (CAD) with respect to localization and number of significant coronary lesions, obtained by direct scrutiny of the original angiograms and the evaluation obtained with the teletransmitted images. RESULTS: In 89 cases of the 98 analyzed (91%) correct diagnosis and surgical approach could be established by distant transmission. In nine cases (9%, all aortocoronary bypass candidates) definitive diagnosis and treatment was feasible only by direct scrutiny of the original angiograms. Five critically ill patients were urgently referred to the surgical care center based on the correct distant diagnosis. The blinded comparison of distant diagnosis and direct scrutiny of angiograms in defining 1-2-3 vessel CAD was good: r=0.87, P<0.01. CONCLUSION: Initial experience using non-sophisticated telemedical transmission of angiograms of cardiac surgery candidates seems to be a promising facility for distantly located centers.

Cardiac Surgical Procedures↗

PubMedDate not supplied

[Progress in optimizing dosimetry plans in stereotactic radiotherapy in the Salt Group (Saint-Anne-Lariboisière-Tenon].

We began intracranial stereotactic irradiation under the direction of O Betti 11 years ago. At the present time, we believe it is interesting to present the methodologies of the SALT (Saint-Anne-Lariboisière-Tenon) group. Up to the present time we have irradiated 693 patients using a single fraction. Arteriovenous malformations (AVMs) represented the majority (90%) of treated lesions. Irradiation protocol has little changed since 1986, and the localization of the target volume was performed in the neurosurgery department of St Anne Hospital, France. The stereotactic images (computerized tomography [CT], angiography) were sent to the radiotherapy department of Tenon Hospital through the French public digital network NUMERIS. Protocol was realized using the stereotactic ARTEMIS-3D/Dosigray TPS. The lesion volume was filled by one or more spherical or elliptical subvolumes using the "Associated Target Methodology". The interactive adjustment of subvolumes was based on the 3D graphical representations of the lesion. The direct optimization of the irradiation space was performed by managing parameters provided by the DDB (Dosimetric Data Base) such as the number of arcs, their angular position, as well as the starting and the ending point of each arc. The evaluation of the calculated dose distribution was made using quantitative parameters. The second method of optimization was based on the minibeam intensity modulation using a mathematical theory of inverse problems and singular value decomposition (SVD) analysis. At the present time, due to technical reasons, linear accelerators do not permit the modulation of intensity of arctherapy. Thus we transformed the profiles of irregular forms into rectangular profiles of modulated ponderation, with each optimized plan being evaluated before its implementation. The criteria of evaluation were derived from the differential and cumulative dose volume histograms (DVH). The DVHs permitted the evaluation of the volumes of underdosage and overdosage inside the lesion and in the healthy tissue, respectively. Using DVHs, we have defined parameters such as the conform factor and the homogeneity index. We stress that the methodology of protocol optimization is valid for single or multiple fractions as well as for intra- and extra-cranial irradiation.

Humans↗

PubMed2003

Screening fetal echocardiography by telemedicine: efficacy and community acceptance.

OBJECTIVE: Our aim was to assess whether tertiary level screening fetal echocardiography can be extended to primary care facilities with telemedicine assistance. METHODS: Assessment of image quality and the adequacy of fetal echocardiograms recorded after random transmission at 128, 384, or 768 kbits/s was performed. Live fetal echocardiograms were transmitted at 384 kbits/s (3 integrated services digital network lines) from the remote primary care center. Patient satisfaction was assessed by surveys obtained after office-based and telemedicine consultations. RESULTS: A total of 58 recorded normal studies had similar image quality and adequacy on transmission at 384 and 768 kbits/s (P =.08 and.49, respectively) and were significantly better than 128 kbits/s (P <.01). During live screening transmitted at 384 kbits/s from the primary care center, 3 of 34 fetuses were diagnosed with heart disease. Surveys from patients with direct physician contact and by telemedicine showed a high satisfaction with telemedicine-assisted screening and counseling. CONCLUSION: Adequate screening for fetal heart disease is technically feasible at or above data transmission rates of 384 kbits/s. Community acceptance for telemedicine-assisted screening and counseling is not adversely affected by a lack of direct personal contact with the specialist.

Behavior↗

PubMed2000

Clinical value of real-time tertiary fetal ultrasound consultation by telemedicine: preliminary evaluation.

Congenital fetal abnormalities are major causes of perinatal mortality and morbidity. The performance of ultrasound in the diagnosis and assessment of fetal anomalies varies enormously between tertiary referral centers and general units. Telemedicine offers a chance for tertiary realtime ultrasound consultations using standard telephone lines for remote sites. Preliminary investigations by our group have shown that real-time transmission of fetal ultrasound images over long distances via telephone (integrated systems digital network [ISDN]) lines is technically feasible. A live link of up to 2 Mb/s was established between Mater Mothers Hospital in Brisbane and Kirwan Hospital for Women in Townsville, which are 1,500 km apart. The objective of the current study was to evaluate the clinical value of a tertiary teleultrasound consultation service. Patients requiring tertiary ultrasound consultations were recruited from North Queensland. Clinicians from the referral site established an initial diagnosis and management plan. Using standard ISDN lines, the real-time ultrasound images were transmitted to the maternal fetal medicine subspecialists in Brisbane. The ultrasound examination was completed under the direction of the subspecialist. The subspecialist explained the findings to the patient at the end of the session, and discussed the diagnosis and management plans with the clinicians involved. Any diagnosis and management variations were classified into minor and major upon agreement by the two teams of clinicians involved. The clinicians and patients in Townsville rated the value of the consultation, and the subspecialists rated the confidence of their diagnoses on five-point scales. Pregnancy outcomes were obtained and the data analyzed. Over a 3-month period, 24 teleultrasound consultations were carried out. The indications for referral were: assessment of growth restriction/fetal wellbeing in the third trimester (6); detailed assessment for high-risk patients (5); evaluation of markers for anomalies (5); isolated fetal anomalies (1); and complex fetal problems such as twin/twin transfusion, multiple anomalies, etc. (7). Overall, the consultations resulted in some modifications to the clinical diagnosis in 45.8% of the cases, and modifications to the management plan in 33.3% of the cases (about half of which were minor variations). The clinicians rated the teleconsultations highly (mean rating 4.7, SD 0.44). The patients also rated the consultations highly, and were comfortable that their privacy and confidentiality were maintained during the consultation. The subspecialists were confident in making their diagnoses by telemedicine (mean score for confidence 4.2, SD 0.43). All the pregnancies have now been completed, with all antenatal diagnoses confirmed to be correct postnatally. Tertiary real-time ultrasound consultation by telemedicine is not only technically feasible, it is welcomed by the clinicians and patients involved. It also contributes to diagnostic and management differences. Larger scale clinical trials are needed to evaluate the true benefits and costs involved. The social benefits in bridging the healthcare gap between the country and the city, and in enabling patients in remote areas to stay close to their family under times of stress is well recognized by all involved.

Congenital Abnormalities↗

PubMed2000

Multipoint videoconferencing in health: a review of three years' experience in Queensland, Australia.

The objective was to review multipoint videoconferencing in Queensland Health from July 1996 to June 1999. Most videoconferencing has been conducted using desktop systems connected by integrated systems digital network (ISDN) at 128 kbps. Data on utilization and problems were extracted from monthly reports and a survey was conducted. Multipoint videoconferencing increased steadily over the 3 years from just and handful of conferences per month to 101 conferences and 703 hours of bridge use per month. Primary uses were education and administration. Relatively few technical failures and operator errors were recorded. But by 1999, late connection and low attendance were major problems. Survey responses indicated that multipoint videoconferencing met expectations at the great majority of sites. Most respondents were satisfied with the level of administrative and technical support provided. In this large and decentralized state, multipoint videoconferencing has proven a useful and effective means of bringing healthcare workers together for a common purpose, supplementing face-to-face events and other encounters mediated by communications technology such as satellite broadcasts and audioconferences.

Attitude of Health Personnel↗

PubMed1999

Live transmission of neonatal echocardiograms from underserved areas: accuracy, patient care, and cost.

OBJECTIVE: Echocardiography is an important tool in the diagnosis and management of critically ill neonates. The authors hypothesized that live telemedicine guidance and interpretation of neonatal echocardiograms from underserved areas would improve management, prevent unnecessary transports, enhance sonographer proficiency, and result in monetary savings. MATERIALS AND METHODS: Using personal computers capable of real-time transmission of echocardiograms over three integrated services digital network (ISDN) telephone lines, pediatric cardiologists interpreted echocardiograms, suggested views to sonographers, and made recommendations to neonatologists 200 miles away. Analyses of accuracy, management, echocardiogram quality, time, and costs were carried out prospectively. RESULTS: Sixty studies were transmitted over 7 months. Indications for echocardiography were suspected congenital heart disease (n = 29), suspected patent ductus arteriosus (PDA) (n = 27), and hemodynamic instability (n = 4). Diagnoses were critical congenital heart disease (n = 4), noncritical heart disease (n = 8), PDA (n = 21), ventricular dysfunction (n = 5), persistent pulmonary hypertension (n = 3), and normal (n = 19). Videotape review confirmed all telemedicine interpretations. The echocardiogram led to immediate change in management in 25 cases (42%), and echocardiogram quality was improved in 53 studies (88%). Time from request to completion of echocardiography was 43+/-30 min. Monetary savings from five avoided transports exceeded all expenses. CONCLUSION: Live transmission of neonatal echocardiograms over three ISDN lines is diagnostic, improves patient care and echocardiography quality, and is cost effective.

Ductus Arteriosus, Patent↗

PubMed1995

Design of a cooperative teleradiology system.

The article describes a teleradiology system intended to provide a user-friendly environment for exchanging images and working cooperatively on them. With the development of a hospital-wide picture archiving and communication system (PACS), the University Hospital of Geneva and several other health institutions in the region became interested in teleradiology. Because of the heterogeneous needs of the potential participants, the following requirements were identified: (1) remote consultation and interpretation of images; and (2) cooperative interpretation of medical images, allowing real-time interaction between physicians. To satisfy these needs, a multipoint teleradiology system has been implemented that incorporates an innovative image display and manipulation software program known as OSIRIS, which supports the full spectrum of imaging modalities. Images and data are transmitted over the public telecommunications Integrated Services Digital Network (ISDN). To accommodate different computing environments at the various locations, platform-independent software has been designed that has the same "look and feel" for PC-Windows, Macintosh, and UNIX-X11 work-stations. The teleradiology system can be used in two modes: synchronous (cooperative) or asynchronous. Special efforts have been made in the development of the synchronous mode. Within the European Telemed Project, a specific protocol has been designed to allow cooperative work between remotely located workstations.

Geriatrics↗

PubMed1998

Real-time telementoring in ophthalmology.

PURPOSE: To determine if current telemedicine technology can support real-time telementoring to teach ophthalmologic surgical procedures in remote areas. METHOD: Using an integrated systems digital network (ISDN) line conveying information at a rate of 128 kbps, an endoscopic laser-assisted dacryocystorhinostomy (ELA-DCR) procedure was transmitted in real time from the Saint Francis Medical Center in Honolulu, Hawaii, to ophthalmologists at the Makati Medical Center in Manila, Philippines, more than 5000 miles away. Live surgical and endoscopic images were sent real time with explanations by the surgeon and with interactive questions and answers during and after the procedure. RESULTS: The ELA-DCR procedure was transmitted in real time from Honolulu to more than 100 ophthalmologists at the Makati Medical Center in the Philippines. CONCLUSION: Current technology in telemedicine can support the use of real-time surgical telementoring to teach complex ophthalmologic procedures.

Computer Communication Networks↗

PubMed2000

Digital radiography with a large-area, amorphous-silicon, flat-panel X-ray detector system.

RATIONALE AND OBJECTIVES: To investigate the image quality of a digital radiography system with an amorphous-silicon, large-area, digital flat-panel detector. METHODS: A flat-panel detector based on a matrix of amorphous silicon was integrated into a projection radiography system. The scintillator consisted of a layer of structured cesium iodide. The active matrix size of 30002 pixels together with a pixel size of 143 microm provided a large image area of 43 x 43 cm2. Basic image quality parameters such as detective quantum efficiency (DQE) and modulation transfer function (MTF) were measured and compared with those obtained with conventional systems. RESULTS: The measurement of DQE yielded a high value of 70% at zero spatial frequency. At a system dose equivalent to 400 speed, the DQE of the digital system was a factor of two larger than the DQE of a storage phosphor or screen-film system within the entire spatial frequency range between zero and the Nyquist limit of 3.5 line pairs per millimeter. The flat-panel detector furthermore has an MTF that is superior to that in regular screen-film systems and also provides a substantially larger dynamic range. CONCLUSIONS: This new technology demonstrates its potential to provide equal or superior image quality to conventional screen-film systems and to reduce patient exposure to radiation dose. The advantages of digital radiography systems, based on a flat-panel detector as an instant image display, facilitation of work flow in the radiology department, and digital networking and archiving, are well in sight.

Humans↗

PubMed1999

The effectiveness of videophones in home healthcare for the elderly.

OBJECTIVES: This study evaluates the effectiveness of telecare, the use of videophones in healthcare for the elderly in communities, and proposes an effective application of telecare in home healthcare. METHODS: An intervention study design was applied to evaluate the add-on benefits to home healthcare from a videophone system using Integrated Services Digital Network (ISDN) installed in individual homes of clients and service providers. An intervention group of home healthcare cases were provided with videophones (VHHC group), and it was compared to a reference group of regular healthcare cases (HHC group). Persons from the 2 groups were individually matched according to sex, age, and their independence in activities of daily living. The functional independence of the individuals in the 2 groups was assessed before and 3 months after home healthcare was started, with and without videophones. The effectiveness of videophones was assessed by analyzing the improvements in functional independence using a paired t test. RESULTS: Improvements in functional independence of 5 pairs of males and 11 pairs of females were analyzed. Improvements in ADL, communication, and social cognition independence of the VHHC group over the 3-month trial period measured by the Functional Independence Measure were 1.5 points, 0.7 points, and 1.9 points, respectively; statistically, these were significantly greater than those of the HHC group (individually P < 0.05). CONCLUSIONS: The effectiveness of the videophones in home healthcare service was found to be significant. This evidence supports the use of videophones in home healthcare to improve the quality of service.

Activities of Daily Living↗

PubMedDate not supplied

The evolution and evaluation of videoconferencing technology for graduate nursing education.

The Integrated Services Digital Network H.323 (ISDN), which has been in use for the past 20 years often requires a dedicated telephone line and other equipment to implement. Consequently, expansion of ISDN-based videoconferencing requires infrastructure not always accessible in those areas that are most in need of technological connections. New H.323 technology using Internet Protocol H.320 (IP) connectivity can accommodate the use in a variety of videoconferencing software and fill this void as demonstrated by an experiment conducted live at the Syllabus Web '99 conference. When a faculty group were unable to secure ISDN connections to demonstrate their clinical evaluation of Family Nurse Practitioner (FNP) students using videoconferencing technology, an ad hoc group of computer experts, educators, instructional design specialists, and corporate sponsors collaborated to design a multipoint PC-based connection using IP connectivity. This article describes the first application of this technology, the evolution of ISDN and IP systems in nursing education and practice, and suggests appropriate future trends for their utility in nursing.

Computer-Assisted Instruction↗

PubMed2005

The use of a telematic connection for the follow-up of hypertensive patients improves the cardiovascular prognosis.

BACKGROUND: Inadequate blood pressure (BP) control could be due to incorrect management of hypertensives caused by the lack of interaction between general practitioners (GP) and hypertension specialists. OBJECTIVES: To test the effectiveness on BP and total cardiovascular risk (TCVR) control of an internet-based digital network connecting specialists and GPs. METHODS: We created a network among the Hypertension Clinic, Federico II University (Naples, Italy), 23 hospital-based hypertension clinics and 60 GPs from the area (CampaniaSalute Network, CS). Randomized GPs enrolled in CS could update online records of patients (n = 1979). As a control, we included 2045 patients referred to the specialist clinics by GPs from outside the network. All patients completed a 2-year follow-up. RESULTS: CS provided a larger reduction in BP [systolic/diastolic BP (SBP/DBP): 7.3 +/- 0.4/5.4 +/- 0.3 versus 4.1 +/- 0.4/3.1 +/- 0.26 mmHg, CS versus control; P < 0.001 for both] and percentage of patients with BP < 140/90 mmHg (CS versus control: baseline, 33 versus 34%, NS; end of follow-up, 51 versus 47%, chi = 13.371; P < 0.001). A European Society of Hypertension-European Society of Cardiology (ESH/ESC) TCVR score was calculated [from 1 (average) to 5 (very high TCVR)]. The CS group showed a reduction in the mean TCVR score (CS: from 3.5 +/- 0.02 to 3.2 +/- 0, P < 0.01, ANOVA; control group: 3.5 +/- 0.03 to 3.4 +/- 0.03, NS) and, accordingly, fatal and non-fatal major cardiovascular events (MACE) were less frequent (2.9 versus 4.3%; chi = 5.047, P < 0.02). CS predicts fewer MACE in multiple binary regression analysis (beta:-7.27, P < 0.008) reducing the risk for MACE compared to control [odds ratio (OR): 0.838; 95% confidence interval (CI): 0.73-0.96]. CONCLUSION: Our results support the idea that telemedicine can achieve better control of BP and TCVR.

Adolescent↗

PubMed2005

A tele-operated mobile ultrasound scanner using a light-weight robot.

This paper presents a new tele-operated robotic chain for real-time ultrasound image acquisition and medical diagnosis. This system has been developed in the frame of the Mobile Tele-Echography Using an Ultralight Robot European Project. A light-weight six degrees-of-freedom serial robot, with a remote center of motion, has been specially designed for this application. It holds and moves a real probe on a distant patient according to the expert gesture and permits an image acquisition using a standard ultrasound device. The combination of mechanical structure choice for the robot and dedicated control law, particularly nearby the singular configuration allows a good path following and a robotized gesture accuracy. The choice of compression techniques for image transmission enables a compromise between flow and quality. These combined approaches, for robotics and image processing, enable the medical specialist to better control the remote ultrasound probe holder system and to receive stable and good quality ultrasound images to make a diagnosis via any type of communication link from terrestrial to satellite. Clinical tests have been performed since April 2003. They used both satellite or Integrated Services Digital Network lines with a theoretical bandwidth of 384 Kb/s. They showed the tele-echography system helped to identify 66% of lesions and 83% of symptomatic pathologies.

Algorithms↗

PubMed1996

Medical teaching at a peripheral site by videoconferencing.

The departments of Child Health and Mental Health of Aberdeen University's Medical Faculty recently took part in a 3 month trial assessing the potential of videoconferencing as a medium for teaching students on peripheral hospital attachments. The equipment used was British Telecom's VC7000 Videoconferencing System and an ISDN2 (integrated services digital network) connection, which was installed between two sites. The locations used were a teaching room in the Royal Aberdeen Children's Hospital and the Paediatric Unit at Raigmore Hospital in Inverness. This paper describes the resources required to support the trial, the methods used to run it and the results of staff and student evaluation of the trial. Evaluation forms were completed and returned by eight members of staff and by 30 fourth- and fifth-year medical students. The results indicated that, although after this particular trial both staff and students rated the overall usefulness as low, they attributed this to technical problems and limitations specific to the type of equipment used rather than to the method itself. The overall impression was that videoconferencing with ISDN has potential as a teaching tool in the medical undergraduate course but that further improvements in image quality and voice switching are required.

Education, Medical, Undergraduate↗

PubMed1996

Frozen-section services by telepathology: experience of 100 cases in the San-in District, Japan.

The early experience is reported here of the use of intra-operative frozen-section service by telepathology using the integrated Service Digital Network (ISDN), a commercially available system that is being connected between the Department of Pathology of Tottori University and Matsue City Hospital, a distance of 30 km. The transfer rate is currently 64 kbit/s. The frozen-section service was conducted for a total of 117 tissue specimens (organs) from 100 patients between August 1993 and May 1995. The average time taken for examination of each specimen of frozen section was 13 min, ranging between 2 and 42 min. The average number of transmitted images was 6.2. Six cases necessitated more than 11 transmitted images to make a diagnosis, while 13 cases could be diagnosed from two images only. Correct and permissible diagnoses were obtained in 109 (93.2%) out of 117 specimens when comparing the telepathology diagnosis with that of direct microscopy. Improper or misdiagnosis was made for eight cases (specimens), which were misinterpreted as papillary carcinoma in Basedow's disease, adenoma and hyperplasia in two pheochromocytomas, solid-tubular carcinoma in phyllodes tumor, mastopathy in invasive carcinoma, metastatic carcinoma in astrocytoma, follicular lymphoma in reactive hyperplasia, and lymphadenitis in follicular lymphoma. In retrospect, diagnosis of these cases should have been deferred. From the results, it was concluded that the intraoperative frozen-section service by telepathology may be a worthwhile substitute for hospitals with limited accessibility to local pathology service, in spite of pitfalls in some cases. Well prepared, high-quality frozen section, sufficient verbal communication with surgeons, and a rather conservative attitude on the part of a well-trained pathologist seem to be the essential ingredients for reaching an accurate decision when using telepathology.

Computer Communication Networks↗

PubMed1999

Application of a low cost telemedicine link to the diagnosis of neonatal congenital heart defects by remote consultation.

OBJECTIVE: To determine whether accurate remote echocardiographic diagnosis of congenital heart disease could be achieved using a low cost telemedicine system. DESIGN: Echocardiographic images obtained by a paediatrician from neonates suspected of having congenital heart disease were transmitted by a telemedicine link across two integrated service digital network (ISDN) lines to a regional paediatric cardiology unit for interpretation by a consultant paediatric cardiologist. The "tele-echo" diagnosis was verified by the paediatric cardiologist on direct consultation and echocardiography. SETTING: Neonatal unit of Altnagelvin Hospital, Londonderry (a district general hospital) and the regional paediatric cardiology department, Royal Belfast Hospital for Sick Children. MAIN OUTCOME MEASURES: Accuracy of the diagnosis made using the telemedicine link; impact on patient management. RESULTS: Between September 1995 and September 1997 echocardiographic images were transmitted on 63 patients. A diagnosis was made in 61 (97%) (transmitted images were unsatisfactory in two). Congenital heart disease was diagnosed in 42 patients. Fourteen patients with major congenital heart disease were accurately diagnosed within 24 hours of admission using the telemedicine link and were transferred to the regional paediatric cardiology unit. A further 28 with less serious congenital heart disease continued to be managed at the district general hospital. Congenital heart disease was excluded in 19. Follow up consultation confirmed accurate diagnosis or exclusion of congenital heart disease in 57 (93%). There were four inaccurate diagnoses (6.3%; three undetected small ventricular septal defects and one pulmonary stenosis). CONCLUSIONS: Transmitted images were of sufficient quality to allow confirmation or exclusion of major congenital heart disease. The telemedicine link facilitated early diagnosis and initiation of appropriate management in patients with complex congenital heart disease and avoided the need for transfer in those where significant congenital heart disease was excluded.

Costs and Cost Analysis↗

PubMed1999

Assessment of the quality of neonatal echocardiographic images transmitted by ISDN telephone lines.

OBJECTIVE: To assess the quality of echocardiographic images from neonates transmitted over Integrated Service Digital Network 2 (ISDN2) channels. DESIGN: Echocardiographic images were viewed live in real time either by a direct video link or by transmission over the commercial network, using one, two, or three ISDN2 channels. The order of the viewing formats was random and four observers marked each view for potential for provision of complete diagnostic information and quality. SETTING: Cardiology department of tertiary referral centre for paediatric cardiac services. ISDN lines were positioned in two nearby rooms. Telephone connection was through the commercial network and video connection by a direct video cable. PATIENTS: 10 neonates were studied (weight 2600 to 3900 g). In each, nine echocardiographic studies were undertaken to assess imaging (M mode and cross sectional) and Doppler (spectral and colour) quality. RESULTS: No significant differences were found in diagnostic ability between the different formats for M mode, colour, or spectral Doppler studies. For cross sectional imaging the diagnostic information and image quality increased with increasing numbers of ISDN channels. With six channels there was little difference from the directly connected images. CONCLUSIONS: In echocardiographic assessment of the newborn, one or two ISDN2 channels will transmit images of satisfactory quality in many situations but three or more channels are necessary to ensure minimum degradation of the live image.

Echocardiography↗

PubMed1989

Ultra-high-speed teleradiology with ISDN technology.

A solid-state, personal computer-based, image digitization and transmission system was developed that uses integrated services digital network (ISDN), a technology under development for ultra-high-speed data transmission over normal phone lines. Thousands of images have been transmitted to a site more than 15 miles away, with data rates exceeding 56,000 bits or 7,000 bytes (1 byte = 8 bits) per second with nearly perfect accuracy. Present modification of the system hardware and software should increase the data rate to 128,000 bits, or 16,000 bytes, per second. With this rate of transmission, remote radiologic image transmission should become a practical, routinely available diagnostic tool.

Computer Communication Networks↗