The effect of transmission bandwidth on diagnostic accuracy in remote fetal ultrasound scanning

Small Animal Teleultrasound

Teleradiology is well established in many small animal practices, whereas teleultrasound is slowly gaining prominence. The demand for teleultrasound services in the veterinary profession has increased substantially because access to ultrasound to general practitioners increases faster than the number of imaging specialists and Point of Care Ultrasound (POCUS) becomes part of the standard of care. Two main methods of teleultrasound currently exist: asynchronous (eg, "store-and-forward") and synchronous (eg, real-time) interpretations. Few standardized protocols for teleultrasound in small animals are available. Similarly, there are no standardized training programs for sonographic examination acquisition and interpretation outside of the traditional diagnostic imaging residency under the purview of the American College of Veterinary Radiology. The success of a telesonographic evaluation largely depends on the relationship between the veterinarian requesting remote assistance and the expert providing support.

Telementored ultrasonography: a narrative review

BACKGROUND

Teleradiology consists of electronic transmission of radiological images from one location to another, including between countries, for interpretation and/or consultation. It is one of the most successful applications of telemedicine. Combining this methodology with ultrasound (called telesonography) can accelerate the process of making diagnoses. Despite this rationale, the quality of the evidence about the effectiveness and accuracy of teleradiology remains unknown.

OBJECTIVE

To review the literature on the evidence that exists regarding use of telemedicine for ultrasound in situations of synchronous transmission.

DESIGN AND SETTING

Narrative review conducted within the evidence-based health program at a federal university in São Paulo (SP), Brazil.

METHODS

A search of the literature was carried out in April 2020, in the online databases MEDLINE, EMBASE, Cochrane Library, Tripdatabase, CINAHL and LILACS, for original publications in all languages. The reference lists of the studies included and the main reviews on the subject were also evaluated.

RESULTS

We included ten studies that assessed procedures performed by different healthcare professionals, always with a doctor experienced in ultrasound as a distant mentor. Among these, only one study assessed disease diagnoses in relation to real patients.

CONCLUSIONS

Despite the promising position of telesonography within telemedicine, no studies with reasonable methodological quality have yet been conducted to demonstrate its effectiveness.

Obstetric ultrasound: where are we and where are we going?

Diagnostic ultrasound (DUS) is, arguably, the most common technique used in obstetrical practice. From A mode, first described by Ian Donald for gynecology in the late 1950s, to B mode in the 1970s, real-time and gray-scale in the early 1980s, Doppler a little later, sophisticated color Doppler in the 1990s and three dimensional/four-dimensional ultrasound in the 2000s, DUS has not ceased to be closely associated with the practice of obstetrics. The latest innovation is the use of artificial intelligence which will, undoubtedly, take an increasing role in all aspects of our lives, including medicine and, specifically, obstetric ultrasound. In addition, in the future, new visualization methods may be developed, training methods expanded, and workflow and ergonomics improved.

Accuracy of Remote Interpretation of Pediatric Emergency Ultrasound Over Third Generation Networks Across Continents

OBJECTIVE

This study aimed to evaluate live-stream videos for evaluation of pediatric emergency medicine ultrasound using a third generation (3G) network.

METHODS

The interrater reliability of a remote 3G network live-streaming assessment of ultrasound scans for abdominal free fluid, intussusception, and hip effusions was evaluated. Fifty-eight deidentified 6-second video clips in .mp4 format of focused assessment with sonography in trauma scans were downloaded to a laptop. A "bedside" ultrasound expert evaluated each scan and marked it positive or negative for the presence of free fluid. Using an iPhone 3G, Skype was used to connect to the second ultrasound expert located in Addis Ababa, Ethiopia, who reviewed the same scans. When the remote expert returned to the United States, evaluation of the scans was repeated as a second bedside reviewer. Interrater reliability was assessed using the κ statistic and percent agreement. This process was repeated for 44 intussusception scans and 28 hip effusion scans.

RESULTS

The κ values (95% confidence interval) between the bedside and remote evaluators for focused assessment with sonography in trauma, intussusception, and hip effusion were 0.748 (0.576-0.92), 0.816 (0.648-0.984), and 0.764 (0.519-1.0), respectively. The percent agreements after adjusting for chance were 86%, 80%, and 88%, respectively. The κ values between the bedside assessments by each evaluator were 0.851 (0.71-0.992), 0.8 (0.616-0.984), and 0.747 (0.479-0.884), respectively. The percent agreements after adjusting for chance were 92%, 81%, and 88%, respectively.

CONCLUSIONS

Live-stream video conference using cellphones over 3G network is a feasible and accurate method for consultation of ultrasound scans from a remote location.

Teleultrasound: historical perspective and clinical application

The health care of patients in rural or isolated areas is challenged by the scarcity of local resources, limited patient access to doctors and hospitals, and the lack of specialized professionals. This has led to a new concept in telemedicine: teleultrasonography (or teleultrasound), which permits ultrasonographic diagnoses to be performed remotely. Telemedicine and teleultrasonography are effective in providing diagnostic imaging services to these populations and reduce health care costs by decreasing the number and duration of hospitalizations and reducing unnecessary surgical procedures. This is a narrative review to present the potential clinical applications of teleultrasonography in clinical practice. The results indicate that although barriers persist for implementing teleultrasonography in a more universal and routine way, advances in telecommunications, Internet bandwidth, and the high resolution currently available for portable ultrasonography suggest teleultrasonography applications will continue to expand. Teleultrasound appears to be a valuable addition to remote medical care for isolated populations with limited access to tertiary healthcare facilities and also a useful tool for education and training.

Patient perspectives of telemedicine quality

BACKGROUND

The purpose of this study was to explore the quality attributes required for effective telemedicine encounters from the perspective of the patient.

METHODS

We used a multi-method (direct observation, focus groups, survey) field study to collect data from patients who had experienced telemedicine encounters. Multi-perspectives (researcher and provider) were used to interpret a rich set of data from both a research and practice perspective.

RESULTS

The result of this field study is a taxonomy of quality attributes for telemedicine service encounters that prioritizes the attributes from the patient perspective. We identify opportunities to control the level of quality for each attribute (ie, who is responsible for control of each attribute and when control can be exerted in relation to the encounter process). This analysis reveals that many quality attributes are in the hands of various stakeholders, and all attributes can be addressed proactively to some degree before the encounter begins.

CONCLUSION

Identification of the quality attributes important to a telemedicine encounter from a patient perspective enables one to better design telemedicine encounters. This preliminary work not only identifies such attributes, but also ascertains who is best able to address quality issues prior to an encounter. For practitioners, explicit representation of the quality attributes of technology-based systems and processes and insight on controlling key attributes are essential to implementation, utilization, management, and common understanding.

Trans-Pacific tele-ultrasound image transmission of fetal central nervous system structures

OBJECTIVE

To assess the quality of images and video clips of fetal central nervous (CNS) structures obtained by ultrasound and transmitted via tele-ultrasound from Brazil to Australia.

METHODS

In this cross-sectional study, 15 normal singleton pregnant women between 20 and 26 weeks were selected. Fetal CNS structures were obtained by images and video clips. The exams were transmitted in real-time using a broadband internet and an inexpensive video streaming device. Four blinded examiners evaluated the quality of the exams using the Likert scale. We calculated the mean, standard deviation, mean difference, and p values were obtained from paired t tests.

RESULTS

The quality of the original video clips was slightly better than that observed by the transmitted video clips; mean difference considering all observers = 0.23 points. In 47/60 comparisons (78.3%; 95% CI = 66.4-86.9%) the quality of the video clips were judged to be the same. In 182/240 still images (75.8%; 95% CI = 70.0-80.8%) the scores of transmitted image were considered the same as the original.

CONCLUSION

We demonstrated that long distance tele-ultrasound transmission of fetal CNS structures using an inexpensive video streaming device provided images of subjective good quality.

Inexpensive, realtime tele-ultrasound using a commercial, web-based video streaming device

We have devised an inexpensive, web-based tele-ultrasound system using commercially-available video streaming equipment. We examined the spatial and grey scale resolution, and the delay time of the system. The receiving PC was tested at various distances from the transmitting site, from 3.2 km to 4828 km. Standard resolution targets and echocardiography movie strips recorded on DVDs were used to assess the image quality. A qualitative assessment was made by an expert sonographer. As the distance between the transmitter and the receiver increased, the scan smoothness decreased and the delay increased. At a distance of 3.2 km the delay was 2–3 s, and at 4828 km it was 10–15 s. The delay was short enough to allow realtime guidance of the scanning technician by telephone. The system allows inexpensive, readily available, realtime tele-ultrasonography.

Telemedicine: technology mediated service relationship, encounter, or something else?

PURPOSE

Service interactions between service providers and health care consumers happen daily in health care organizations, and can occur face-to-face or through mediating technology. We use the demanding and rich environment of telemedicine to better understand the nature of the real time service-encounter interactions among the human and technology actors engaged in the process and to inform telemedicine providers about key factors to consider in telemedicine design.

METHODS

We conducted a case study of medical video conferencing (MVC) for the delivery of patient healthcare (a form of telemedicine) using multiple data collection and analysis techniques involving a range of telemedicine stakeholders.

RESULTS

The research reveals that telemedicine requires a new kind of service relationship, an Advanced Encounter, with unique relationships between the telemedicine service providers, presenters, patients, and technology. Seven facilitating factors for the Advanced Encounter of telemedicine are identified and discussed, including the telemedicine servicescape: a set of supporting structures that are critical to telemedicine success.

CONCLUSIONS

Key contributions are a deep understanding of the relationships between telemedicine actors, and the organizational actions needed to deploy a technology-mediated telemedicine service.

Tele-obstetric ultrasound: analysis of first-trimester ultrasound images transmitted in realtime

We evaluated the diagnostic quality of first-trimester ultrasound images transmitted in realtime using low-cost telecommunications. A prospective sample of fetal ultrasound images from 11 weeks to 13 weeks and six days of pregnancy was obtained from pregnant women over 18 years old. The examinations were transmitted in realtime to three independent examiners who carried out a qualitative assessment based on parameters established by the Fetal Medicine Foundation. All fetal structures could be viewed and the quality of images received by the examiners was considered normal. There were significant differences for crown-rump length and nuchal translucency in the transmitted images but the loss in definition was acceptable. Thus the quality of images transmitted via the Internet through the use of low-cost software appeared suitable for screening for chromosomal abnormalities in the first trimester of pregnancy.

Real-time video transmission of ultrasound images to an iPhone

Background

As point-of-care ultrasound spreads across the globe, there is an increased need for training and supervision of ultrasound studies. Real-time oversight is important, especially in critically ill patients, but often an expert ultrasound over-read is not available on location. Technological advances have improved data transmission so that images and videos can be sent great distances very rapidly. In this study, we examine the feasibility of real-time wireless transmission of ultrasound video to an iPhone.

Methods

An ultrasound machine was connected via a video converter to a laptop. iCam (SKJM, LLC) software was used to transmit the video across the Atlantic Ocean to an iPhone. Images typical for those performed in an emergency department were sent, in random order by a ‘scanning physician.’ An ‘interpreting physician’ overseas was asked to identify the anatomy, presence or absence of pathology, and comment on the quality, speed, and delay of transmission.

Results

Rapid image transmission was feasible and the ‘interpreting physician’ was always able to correctly identify the anatomy and orientation. The average delay was minimal (2.7 s), allowing for real-time feedback. The frame rate was markedly slower in the received images as compared to the transmitted images, and was faster when the iPhone was connected via WiFi (1.1 fps) versus a 3G connection (0.4 fps).

Conclusion

Transmission of real-time ultrasound video to a remote iPhone using inexpensive technology is feasible, with the preservation of image quality and minimal delay. Transmission speed was superior with a WiFi connection than with a 3G connection.

Telementoring During Endovascular Treatment of Abdominal Aortic Aneurysms:A Prospective Study

PURPOSE

To explore the use of telementoring for distant teaching and training in endovascular aortic aneurysm repair (EVAR).

METHODS

According to a prospectively designed study protocol, 48 patients underwent EVAR: the first 12 patients (group A) were treated at a secondary care center by an experienced interventionist, who was training the local team; a further 12 patients (group B) were operated by the local team at their secondary center with telementoring by the experienced operator from an adjacent suite; and the last 24 patients (group C) were operated by the local team with remote telementoring support from the experienced interventionist at a tertiary care center. Telementoring was performed using 3 video sources; images were transmitted using 4 ISDN lines. EVAR was performed using intravascular ultrasound and simultaneous fluoroscopy to obtain road mapping of the abdominal aorta and its branches, as well as for identifying the origins of the renal arteries, assessing the aortic neck, and monitoring the attachment of the stent-graft proximally and distally.

RESULTS

Average duration of telementoring was 2.1 hours during the first 12 patients (group B) and 1.2 hours for the remaining 24 patients (group C). There was no difference in procedural duration (127+/-59 minutes in group A, 120+/-4 minutes in group B, and 119+/-39 minutes in group C; p=0.94) or the mean time spent in the ICU (26+/-15 hours in group A, 22+/-2 hours in group B, and 22+/-11 hours for group C; p=0.95). The length of hospital stay (11+/-4 days in group A, 9+/-4 days in group B, and 7+/-1 days in group C; p=0.002) was significantly different only for group C versus A (p=0.002). Only 1 (8.3%) patient (in group A: EVAR performed by the experienced operator) required conversion to open surgery because of iliac artery rupture. This was the only conversion (and the only death) in the entire study group (1/12 in group A versus 0/36 in groups B + C, p=0.31).

CONCLUSIONS

Telementoring for EVAR is feasible and shows promising results. It may serve as a model for development of similar projects for teaching other invasive procedures in cardiovascular medicine.

The effect of bandwidth on the quality of transmitted pediatric echocardiograms

BACKGROUND

Remote access to pediatric cardiology diagnostic services is enabled by real-time transmission of echocardiographic images. Several transmission bandwidths have been used but there has been little analysis of image quality provided by different bandwidths. We designed a study of the quality of transmitted images at various bandwidths.

METHODS

Two echocardiographers viewed randomly a series of 13 recorded pediatric echocardiographic images either directly or after transmission using 1 of 4 bandwidths: 256; 384; 512; or 768 kbps. An image clarity scoring scale was used to assess image quality of cardiac structures.

RESULTS

Measurable differences were found in image quality with different transmission bandwidths; 512 kbps was the minimum for consistently clear imaging of all cardiac structures examined.

CONCLUSION

Bandwidth greater than 512 kbps confers sharper images subjectively although this could not be quantified by our methods.

Tele-echocardiography in paediatrics

Echocardiographic images can be transmitted over increasing distances with less cost and better quality thanks to advances in the field of telecommunications. This technological support can be used to detect heart defects in newborns and children in remote situations. The intent of this study was to confirm the feasibility and usefulness of telemedical communication for echocardiographic evaluation of paediatric cardiovascular disease. A total of 214 echocardiographs were performed in 194 children at a remote hospital by an experienced sonographer in paediatric echocardiography. These echocardiograms were transmitted to a distant tertiary care paediatric cardiology centre using a telemedicine link across three ISDN lines. There an experienced paediatric cardiologist interpreted the tele-echocardiograms. Tele-distant diagnoses were prospectively documented and compared with the diagnoses made subsequently on direct consultation and echocardiography. The quality of transmitted echocardiographic images was sufficient for evaluation except for one case. In 191 children (98%), the remote echocardiographic diagnosis was correct as confirmed by follow-up face to face consultations. Three cases were diagnosed incorrectly.

CONCLUSION

our results confirm that accurate and rapid diagnosis can be provided by tele-echocardiography in neonates and children. This facilitates the appropriate care of these patients as expensive and potentially dangerous long-distance transfers can be avoided.

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.

Tele-ultrasound for remote areas

Summary We studied the introduction of a telemedicine service for the prenatal diagnosis and management of pregnant patients at a remote site in Scotland. During a 10-month study period, 85 videoconferences were carried out between the remote hospital in Elgin and the fetal medicine unit in Aberdeen. ISDN transmission at 384 kbit/s was used. There were technical problems in five calls (6%). The mean call duration was 40 min (range 5-60 min). Most calls (62%) were for educational reasons and 26% were for clinical purposes. The degree of satisfaction recorded by the remote health-care staff was high: the mean score on a five-point scale (1, very unsatisfied; 5, very satisfied) for general satisfaction with the clinical support was 4.2. The system was found to be both clinically useful and educationally beneficial.

Operative fetoscopy via telesurgery

We describe a case in which telesurgical consultation from Tampa, Florida, USA was used to accomplish operative fetoscopy in Santiago, Chile for the treatment of a twin pregnancy involving an acardiac twin. The procedure was successful and a healthy infant was delivered at 37.5 weeks. Operative fetoscopy, a surgical approach to correct birth defects in utero via combined ultrasound and endoscopy, is only available in a handful of centers worldwide. Telesurgery makes use of telecommunication to allow a surgeon at a primary operating site to consult with another experienced surgeon for complex surgical cases. This case illustrates the potential for ultrasound and telesurgery to expand the horizons of operative fetoscopy.

The development of a pilot telemedicine network in Scotland: lessons learned

A pilot telemedicine network was established in 11 sites using funding provided by the Department of Trade and Industry in the UK. The main purpose of the project was to develop and evaluate clinical and educational links between central and peripheral sites in Scotland. The results were very encouraging, and clinical services were established in accident and emergency medicine, tele-ultrasound and clinical psychology. An undergraduate medical teaching service was also successfully established. All of these services are to be continued after the completion of the project. Many lessons were learned during the establishment of this network which will be useful in future projects. These included the importance of training for telemedicine users, the importance of identifying a telemedicine champion, the pitfall of health economics and the fact that services must be needs driven.

Information acquisition from audio-video-data sources: an experimental study on remote diagnosis. The LOTAS Group

OBJECTIVE

To determine what information sources are used during a remote diagnosis task.

MATERIALS AND METHODS

Experienced trauma care providers viewed segments of videotaped initial trauma patient resuscitation and airway management. Experiment 1 collected responses from anesthesiologists to probing questions during and after the presentation of recorded video materials. Experiment 2 collected the responses from three types of care providers (anesthesiologists, nurses, and surgeons). Written and verbal responses were scored according to detection of critical events in video materials and categorized according to their content. Experiment 3 collected visual scanning data using an eyetracker during the viewing of recorded video materials from the three types of care providers. Eye-gaze data were analyzed in terms of focus on various parts of the videotaped materials.

RESULTS

Care providers were found to be unable to detect several critical events. The three groups of subjects studied (anesthesiologists, nurses, and surgeons) focused on different aspects of videotaped materials.

CONCLUSION

When the remote events and activities are multidisciplinary and rapidly changing, experts linked with audio-video-data connections may encounter difficulties in comprehending remote activities, and their information usage may be biased. Special training is needed for the remote decision-maker to appreciate tasks outside his or her speciality and beyond the boundaries of traditional divisions of labor.

Telemedicine: barriers and opportunities in the 21st century

This paper aims to examine how health telematics will develop in the first 10 years of the new millennium and, in particular, to assess what operational, ethical and legal barriers may lie in the way of this development. A description of the key principles and concepts involved in telemedicine and a short historical overview of telemedicine's evolution over the past century are followed by consideration of why empirical research into 'info-ethics' and other deontological and legal issues relating to telemedicine is being necessarily catalysed by, amongst others, the European Commission. Four evolving health telematics applications are examined in some detail: electronic health records; the transmission of visual media in disciplines such as teleradiology, teledermatology, telepathology and teleophthalmology; telesurgery and robotics and the use of call centres and decision-support software. These are discussed in the light of their moral, ethical and cultural implications for clinicians, patients and society at large. The author argues that telemedicine presents unique opportunities for both patients and clinicians where it is implemented in direct response to clear clinical needs, but warns against excessive reliance upon technology to the detriment of traditional clinician-patient relationships and against complacency regarding the risks and responsibilities - many of which are as yet unknown - that distant medical intervention, consultation and diagnosis carry.

Teleconsultation for cooperative acquisition, analysis and reporting of ultrasound studies

We have developed a teleconsultation system to support cooperation between doctors at different institutions in the acquisition, analysis and reporting of ultrasound studies. All the relevant activities were supported by the application. The system enabled remote supervision of the ultrasound study as it was being performed, cooperative static image acquisition and analysis, as well as report writing. Cooperative analysis of previously acquired studies was also possible. The system is undergoing evaluation in five hospitals in Portugal.