Diagnostic ultrasound at MACH 20: retroperitoneal and pelvic imaging in space

Utility of ultrasound in managing acute medical conditions in space: a scoping review

BACKGROUND

In long-distance spaceflight, the challenges of communication delays and the impracticality of rapid evacuation necessitate the management of medical emergencies by onboard physicians. Consequently, these physicians must be proficient in tools, such as ultrasound, which has proven itself a strong diagnostic imaging tool in space. Yet, there remains a notable gap in the discourse surrounding its efficacy in handling acute medical scenarios. This scoping review aims to present an updated analysis of the evidence supporting the role of ultrasound in diagnosing acute conditions within microgravity environments.

METHODS

A systematic search was executed across three bibliographic databases: PubMed, EMBASE (Embase.com), and the Web of Science Core Collection. We considered articles published up to February 25, 2023, that highlighted the application of ultrasound in diagnosing acute medical conditions in either microgravity or microgravity-simulated settings. Exclusions were made for review papers, abstracts, and in-vitro studies.

RESULTS

After removing duplicates, and filtering papers by pre-determined criteria, a total of 15 articles were identified that discuss the potential use of ultrasound in managing acute medical conditions in space. The publication date of these studies ranged from 1999 to 2020. A relatively similar proportion of these studies were conducted either on the International Space Station or in parabolic flight, with one performed in supine positioning to simulate weightlessness. The included studies discuss acute pathologies, such as abdominal emergencies, decompression sickness, deep venous thrombosis, acute lung pathologies, sinusitis, musculoskeletal trauma, genitourinary emergencies, and ocular emergencies.

CONCLUSIONS

While ultrasound has shown promise in addressing various acute conditions, significant knowledge gaps remain, especially in gastrointestinal, cardiac, vascular, and reproductive emergencies. As we venture further into space, expanding our medical expertise becomes vital to ensure astronaut safety and mission success.

Human Health during Space Travel: State-of-the-Art Review

The field of human space travel is in the midst of a dramatic revolution. Upcoming missions are looking to push the boundaries of space travel, with plans to travel for longer distances and durations than ever before. Both the National Aeronautics and Space Administration (NASA) and several commercial space companies (e.g., Blue Origin, SpaceX, Virgin Galactic) have already started the process of preparing for long-distance, long-duration space exploration and currently plan to explore inner solar planets (e.g., Mars) by the 2030s. With the emergence of space tourism, space travel has materialized as a potential new, exciting frontier of business, hospitality, medicine, and technology in the coming years. However, current evidence regarding human health in space is very limited, particularly pertaining to short-term and long-term space travel. This review synthesizes developments across the continuum of space health including prior studies and unpublished data from NASA related to each individual organ system, and medical screening prior to space travel. We categorized the extraterrestrial environment into exogenous (e.g., space radiation and microgravity) and endogenous processes (e.g., alteration of humans' natural circadian rhythm and mental health due to confinement, isolation, immobilization, and lack of social interaction) and their various effects on human health. The aim of this review is to explore the potential health challenges associated with space travel and how they may be overcome in order to enable new paradigms for space health, as well as the use of emerging Artificial Intelligence based (AI) technology to propel future space health research.

Patient Self-Performed Point-of-Care Ultrasound: Using Communication Technologies to Empower Patient Self-Care

Point-of-Care ultrasound (POCUS) is an invaluable tool permitting the understanding of critical physiologic and anatomic details wherever and whenever a patient has a medical need. Thus the application of POCUS has dramatically expanded beyond hospitals to become a portable user-friendly technology in a variety of prehospital settings. Traditional thinking holds that a trained user is required to obtain images, greatly handicapping the scale of potential improvements in individual health assessments. However, as the interpretation of ultrasound images can be accomplished remotely by experts, the paradigm wherein experts guide novices to obtain meaningful images that facilitate remote care is being embraced worldwide. The ultimate extension of this concept is for experts to guide patients to image themselves, enabling secondary disease prevention, home-focused care, and self-empowerment of the individual to manage their own health. This paradigm of remotely telementored self-performed ultrasound (RTMSPUS) was first described for supporting health care on the International Space Station. The TeleMentored Ultrasound Supported Medical Interventions (TMUSMI) Research Group has been investigating the utility of this paradigm for terrestrial use. The technique has particular attractiveness in enabling surveillance of lung health during pandemic scenarios. However, the paradigm has tremendous potential to empower and support nearly any medical question poised in a conscious individual with internet connectivity able to follow the directions of a remote expert. Further studies and development are recommended in all areas of acute and chronic health care.

Achieving universal access to obstetric ultrasound in resource constrained settings: A narrative review

OBJECTIVES

The potential benefits and challenges of achieving universal access to obstetric ultrasound services in resource constrained settings were reviewed, with a view to making some recommendations to address the huge burden of avoidable maternal and child morbidity and mortality.

KEY FINDINGS

In most resource-poor settings of the world, antenatal ultrasound is available only to a privileged few in urban centres, while the majority of the population living in rural areas have little or no access to diagnostic imaging services. There is also the extreme shortage of sonographers and doctors with specialist training in sonography. A comprehensive regulation must be put in place to achieve maximum benefits and to ensure quality assurance; appropriate use and application of ethics and training must be comprehensive.

CONCLUSION

Ultrasound service provision, in resource-scarce settings, has the potential to improve access and quality of health care services in areas like the point of care ultrasound service provision and in the fields of obstetrics and gynaecology. A comprehensive regulation must be put in place to achieve maximum benefits and to ensure quality assurance.

IMPLICATIONS FOR PRACTICE

Making ultrasound technology available and affordable in resource scare settings has the potential to improve access to diagnostic imaging services and reduce avoidable maternal and child death in resource constrained settings.

Review of Health Economics of Point-of-Care Testing Worldwide and Its Efficacy of Implementation in the Primary Health Care Setting in Remote Australia

There are important differences concerning health outcomes between the Australian population living in rural/remote regions and the urban population. Health care provision in remote areas, particularly in regions with a low number of inhabitants, is not without challenges. Aboriginal, rural and remote communities are therefore affected, as they face various obstacles in accessing health services, owing to geographical settings, difficulties in transportation to nearby hospitals, limited or inexistent local qualified personnel. The implementation of point-of-care testing could be a plausible solution to these challenges, as various point-of-care services that have been successfully put into action worldwide indicate towards positive clinical outcomes. Point-of-care units have a real potential in reducing morbidity and mortality in all population groups. This article aims to review the published literature on point-of-care testing around the world, with a focus on health economics and the feasibility of its implementation in Australian rural and remote regions.

Point-of-Care Teleultrasound: A Systematic Review

Background: Telemedicine and point-of-care ultrasound have merged to create a field known as teleultrasound (TUS). Real-time TUS involves the transmission of bedside ultrasound (US) images with direct feedback from an US expert. In this review, we summarize the current uses of real-time TUS and discuss its potential future uses. Methods: We performed a literature search (PubMed and EMBase) to assess articles related to real-time TUS. Data were extracted using a standardized collection form, and relevant articles were separated into feasibility or clinical studies. Results: Our search yielded 45 articles, with most of the reports taking place in resource-constrained settings. A large portion of the studies discussed the use of the focused assessment with sonography in trauma exam. Others included musculoskeletal, vascular, and echocardiography. Conclusion: Real-time TUS allows for rapid access to diagnostic imaging in various clinical settings. This technology is poised to expand with many uses on the horizon.

Applications of Space Technologies to Global Health: Scoping Review

Background

Space technology has an impact on many domains of activity on earth, including in the field of global health. With the recent adoption of the United Nations’ Sustainable Development Goals that highlight the need for strengthening partnerships in different domains, it is useful to better characterize the relationship between space technology and global health.

Objective

The aim of this study was to identify the applications of space technologies to global health, the key stakeholders in the field, as well as gaps and challenges.

Methods

We used a scoping review methodology, including a literature review and the involvement of stakeholders, via a brief self-administered, open-response questionnaire. A distinct search on several search engines was conducted for each of the four key technological domains that were previously identified by the UN Office for Outer Space Affairs’ Expert Group on Space and Global Health (Domain A: remote sensing; Domain B: global navigation satellite systems; Domain C: satellite communication; and Domain D: human space flight). Themes in which space technologies are of benefit to global health were extracted. Key stakeholders, as well as gaps, challenges, and perspectives were identified.

Results

A total of 222 sources were included for Domain A, 82 sources for Domain B, 144 sources for Domain C, and 31 sources for Domain D. A total of 3 questionnaires out of 16 sent were answered. Global navigation satellite systems and geographic information systems are used for the study and forecasting of communicable and noncommunicable diseases; satellite communication and global navigation satellite systems for disaster response; satellite communication for telemedicine and tele-education; and global navigation satellite systems for autonomy improvement, access to health care, as well as for safe and efficient transportation. Various health research and technologies developed for inhabited space flights have been adapted for terrestrial use.

Conclusions

Although numerous examples of space technology applications to global health exist, improved awareness, training, and collaboration of the research community is needed.

Recent Developments in Tele-Ultrasonography

A long-standing trend that will continue to grow in healthcare is providing high quality services for all the patient, no matter the distance and no matter the place. One approach currently being used to increase population access to healthcare services is telemedicine. This narrative review presents one branch of e-health, in particular the use of teleultrasonography (TUS) in clinical practice, the challenges and barriers encountered. Current advances in ultrasound technology, including the growth of portable and small ultrasound devices have increased the range of applications of TUS, from traumatic patients in emergency medicine, maternal ultrasound and even for monitoring and screening for chronic illnesses. Even though some barriers are still looking for a solution, like standardized training and protocols, errors in data acquisition, the lack of trained professionals to operate in remote areas, TUS has the potential to redesign future health care systems.

Training Midwives to Perform Basic Obstetric Point-of-Care Ultrasound in Rural Areas Using a Tablet Platform and Mobile Phone Transmission Technology-A WFUMB COE Project

Point-of-care ultrasound (POCUS) has become a topical subject and can be applied in a variety of ways with differing outcomes. The cost of all diagnostic procedures including obstetric ultrasound examinations is a major factor in the developing world and POCUS is only useful if it can be equated to good outcomes at a lower cost than a routine obstetric examination. The aim of this study was to assess a number of processes including accuracy of images and reports generated by midwives, performance of a tablet-sized ultrasound scanner, training of midwives to complete ultrasounds, teleradiology solution transmissions of images via internet, review of images by a radiologist, communication between midwife and radiologist, use of this technique to identify high-risk patients and improvement of the education and teleradiology model components. The midwives had no previous experience in ultrasound. They were stationed in rural locations where POCUS was available for the first time. After scanning the patients, an interim report was generated by the midwives and sent electronically together with all images to the main hospital for validation. Unique software was used to send lossless images by mobile phone using a modem. Transmission times were short and quality of images transmitted was excellent. All reports were validated by two experienced radiologists in our department and returned to the centers using the same transmission software. The transmission times, quality of scans, quality of reports and other parameters were recorded and monitored. Analysis showed excellent correlation between provisional and validated reports. Reporting accuracy of scans performed by the midwives was 99.63%. Overall flow turnaround time (from patient presentation to validated report) was initially 35 min but reduced to 25 min. The unique mobile phone transmission was faultless and there was no degradation of image quality. We found excellent correlation between final outcomes of the pregnancies and diagnoses on the basis of reports generated by the midwives. Only 1 discrepancy was found in the midwives' reports. Scan results versus actual outcomes revealed 2 discrepancies in the 20 patients identified as high risk. In conclusion, we found that it is valuable to train midwives in POCUS to use an ultrasound tablet device and transmit images and reports via the internet to radiologists for review of accuracy. This focus on the identification of high-risk patients can be valuable in a remote healthcare facility.

The Damage Control Surgery in Austere Environments Research Group (DCSAERG): A dynamic program to facilitate real-time telementoring/telediagnosis to address exsanguination in extreme and austere environments

Hemorrhage is the most preventable cause of posttraumatic death. Many cases are potentially anatomically salvageable, yet remain lethal without logistics or trained personnel to deliver diagnosis or resuscitative surgery in austere environments. Revolutions in technology for remote mentoring of ultrasound and surgery may enhance capabilities to utilize the skill sets of non-physicians. Thus, our research collaborative explored remote mentoring to empower non-physicians to address junctional and torso hemorrhage control in austere environments. Major studies involved using remote-telementored ultrasound (RTMUS) to identify torso and junctional exsanguination, remotely mentoring resuscitative surgery for torso hemorrhage control, understanding and mitigating physiological stress during such tasks, and the technical practicalities of conducting damage control surgery (DCS) in austere environments. Iterative projects involved randomized guiding of firefighters to identify torso (RCT) and junctional (pilot) hemorrhage using RTMUS, randomized remote mentoring of MedTechs conducting resuscitative surgery for torso exsanguination in an anatomically realistic surgical trainer ("Cut Suit") including physiological monitoring, and trained surgeons conducting a comparative randomized study for torso hemorrhage control in normal (1g) versus weightlessness (0g). This work demonstrated that firefighters could be remotely mentored to perform just-in-time torso RTMUS on a simulator. Both firefighters and mentors were confident in their abilities, the ultrasounds being 97% accurate. An ultrasound-naive firefighter in Memphis could also be remotely mentored from Hawaii to identify and subsequently tamponade an arterial junctional hemorrhage using RTMUS in a live tissue model. Thereafter, both mentored and unmentored MedTechs and trained surgeons completed resuscitative surgery for hemorrhage control on the Cut-Suit, demonstrating practicality for all involved. While remote mentoring did not decrease blood loss among MedTechs, it increased procedural confidence and decreased physiologic stress. Therefore, remote mentoring may increase the feasibility of non-physicians conducting a psychologically daunting task. Finally, DCS in weightlessness was feasible without fundamental differences from 1g. Overall, the collective evidence suggests that remote mentoring supports diagnosis, noninvasive therapy, and ultimately resuscitative surgery to potentially rescue those exsanguinating in austere environments and should be more rigorously studied.

Up and Away: Five Decades of Urologic Investigation in Microgravity

A renewed global interest in manned space exploration has emerged, propelled by the challenge of reaching a new frontier: travel to the Red Planet, Mars. As the physiological changes induced by microgravity bear direct relevance to the safety and viability of these goals, we provide a historical narrative of the urologic investigations in space. We review the significant contributions to the understanding of the urologic consequences associated with exposure to microgravity, considerations for prolonged missions, and forward-looking efforts to manage emergent conditions remotely. Historical insights gleaned are poised to inform interplanetary travel, where urologic pathology will remain an important practical consideration.

Point of Care Ultrasound: A WFUMB Position Paper

Over the last decade, the use of portable ultrasound scanners has enhanced the concept of point of care ultrasound (PoC-US), namely, "ultrasound performed at the bedside and interpreted directly by the treating clinician." PoC-US is not a replacement for comprehensive ultrasound, but rather allows physicians immediate access to clinical imaging for rapid and direct solutions. PoC-US has already revolutionized everyday clinical practice, and it is believed that it will dramatically change how ultrasound is applied in daily practice. However, its use and teaching are different from continent to continent and from country to country. This World Federation for Ultrasound in Medicine and Biology position paper discusses the current status and future perspectives of PoC-US. Particular attention is given to the different uses of PoC-US and its clinical significance, including within emergency and critical care medicine, cardiology, anesthesiology, rheumatology, obstetrics, neonatology, gynecology, gastroenterology and many other applications. In the future, PoC-US will be more diverse than ever and be included in medical student training.

Imaging Informatics: 25 Years of Progress

The science and applications of informatics in medical imaging have advanced dramatically in the past 25 years. This article provides a selective overview of key developments in medical imaging informatics. Advances in standards and technologies for compression and transmission of digital images have enabled Picture Archiving and Communications Systems (PACS) and teleradiology. Research in speech recognition, structured reporting, ontologies, and natural language processing has improved the ability to generate and analyze the reports of imaging procedures. Informatics has provided tools to address workflow and ergonomic issues engendered by the growing volume of medical image information. Research in computeraided detection and diagnosis of abnormalities in medical images has opened new avenues to improve patient care. The growing number of medical-imaging examinations and their large volumes of information create a natural platform for "big data" analytics, particularly when joined with high-dimensional genomic data. Radiogenomics investigates relationships between a disease's genetic and gene-expression characteristics and its imaging phenotype; this emerging field promises to help us better understand disease biology, prognosis, and treatment options. The next 25 years offer remarkable opportunities for informatics and medical imaging together to lead to further advances in both disciplines and to improve health.

Making the financial case for a surgeon-directed critical care ultrasound program

BACKGROUND

We sought to demonstrate that a well-staffed, surgeon-directed, critical care ultrasound program (CCUP) is financially sustainable and provides administrative and educational support for point-of-care ultrasound.

METHODS

The CCUP provides a clinical service and training as well as conducts research. Initial costs, annual costs (C), revenue (R), and savings (S) were prospectively recorded. Using data from the first 3 years, we calculated the projected C, R, and S at 5 years. We determined CCUP sustainability by C < R and C < R + S at 3 years and 5 years.

RESULTS

During 36 months, the CCUP covered four surgical intensive care units (55 beds). Start-up costs included one basic and one cardiovascular device per 25 beds and a data storage system linking reports and images to the electronic medical record ($203,650). Billing increased threefold from Years 1 to 3, with a 21% increase between Years 2 to 3. Yearly costs included 0.5 full-time equivalent (FTE) sonographer and 0.2 FTE surgeon ($106,025); this was increased to 1 FTE and 0.25 FTE, respectively, for Years 4 and 5. The total 3-year cost was $521,725 and projected to be $863,325 by Year 5. The total 3-year revenue was $290,775 and projected to be $891,600 at 5 years. The total 3-year savings associated with the CCUP was $600,035 and is projected to be $1,194,220. With the use of the C < R, the CCUP meets operating expenses at Year 3 and covers overall cost at 5 years. If savings are included, then the CCUP is sustainable by its third year and is potentially profitable by Year 5.

CONCLUSION

A surgeon-directed CCUP is financially sustainable, addresses administrative issues, and provides valuable training in point-of-care ultrasound.

Evaluation of tele-ultrasound as a tool in remote diagnosis and clinical management at the Amundsen-Scott South Pole Station and the McMurdo Research Station

Abstract Background: A large number of Antarctic stations do not utilize ultrasound for medical care. Regular use of ultrasound imaging at South Pole and McMurdo Stations first began in October 2002. To date, there has been no evaluation of medical events requiring ultrasound examination from this remote environment. Additionally, the importance of tele-ultrasound for clinical management in Antarctica has not yet been assessed. We therefore conducted a retrospective analysis of all ultrasound exams performed at South Pole and McMurdo Stations between October 2002 and October 2003.

SUBJECTS AND METHODS

Radiology reports and patient charts were reviewed for pre- and post-ultrasound diagnosis and treatment.

RESULTS

Sixty-six ultrasound exams were conducted on 49 patients. Of the exams, 94.0% were interpreted by the store-and-forward method, whereas 6.0% were interpreted in "real-time" format. Abdominal, genitourinary, and gynecology ultrasound exams accounted for 63.6% of exams. Ultrasound examination prevented an intercontinental aeromedical evacuation in 25.8% of cases, and had a significant effect on the diagnosis and management of illness in patients at South Pole and McMurdo research stations.

CONCLUSIONS

These findings indicate that diagnostic ultrasound has significant benefits for medical care at Antarctic stations and that tele-ultrasound is a valuable addition to remote medical care for isolated populations with limited access to tertiary-healthcare facilities.

Potential Use of Remote Telesonography as a Transformational Technology in Underresourced and/or Remote Settings

Mortality and morbidity from traumatic injury are twofold higher in rural compared to urban areas. Furthermore, the greater the distance a patient resides from an organized trauma system, the greater the likelihood of an adverse outcome. Delay in timely diagnosis and treatment contributes to this penalty, regardless of whether the inherent barriers are geographic, cultural, or socioeconomic. Since ultrasound is noninvasive, cost-effective, and portable, it is becoming increasingly useful for remote/underresourced (R/UR) settings to avoid lengthy patient travel to relatively inaccessible medical centers. Ultrasonography is a user-dependent, technical skill, and many, if not most, front-line care providers will not have this advanced training. This is particularly true if care is being provided by out-of-hospital, “nontraditional” providers. The human exploration of space has forced the utilization of information technology (IT) to allow remote experts to guide distant untrained care providers in point-of-care ultrasound to diagnose and manage both acute and chronic illness or injuries. This paradigm potentially brings advanced diagnostic imaging to any medical interaction in a setting with internet connectivity. This paper summarizes the current literature surrounding the development of teleultrasound as a transformational technology and its application to underresourced settings.

Simple, almost anywhere, with almost anyone: remote low-cost telementored resuscitative lung ultrasound

BACKGROUND

Apnea (APN) and pneumothorax (PTX) are common immediately life-threatening conditions. Ultrasound is a portable tool that captures anatomy and physiology as digital information allowing it to be readily transferred by electronic means. Both APN and PTX are simply ruled out by visualizing respiratory motion at the visceral-parietal pleural interface known as lung sliding (LS), corroborated by either the M-mode or color-power Doppler depiction of LS. We thus assessed how economically and practically this information could be obtained remotely over a cellular network.

METHODS

Ultrasound images were obtained on handheld ultrasound machines streamed to a standard free internet service (Skype) using an iPhone. Remote expert sonographers directed remote providers (with variable to no ultrasound experience) to obtain images by viewing the transmitted ultrasound signal and by viewing the remote examiner over a head-mounted webcam. Examinations were conducted between a series of remote sites and a base station. Remote sites included two remote on-mountain sites, a small airplane in flight, and a Calgary household, with base sites located in Pisa, Rome, Philadelphia, and Calgary.

RESULTS

In all lung fields (20/20) on all occasions, LS could easily and quickly be seen. LS was easily corroborated and documented through capture of color-power Doppler and M-mode images. Other ultrasound applications such as the Focused Assessment with Sonography for Trauma examination, vascular anatomy, and a fetal wellness assessment were also demonstrated.

CONCLUSION

The emergent exclusion of APN-PTX can be immediately accomplished by a remote expert economically linked to almost any responder over cellular networks. Further work should explore the range of other physiologic functions and anatomy that could be so remotely assessed.

On-orbit prospective echocardiography on International Space Station crew

OBJECTIVES

A prospective trial of echocardiography was conducted on six crew members onboard the International Space Station. The main objective was to determine the efficacy of remotely guided tele-echocardiography, including just-in-time e-training methods and determine what is "space normal" echocardiographic data.

METHODS

Each crew member operator (n = 6) had 2-hour preflight training. Baseline echocardiographic data were collected 55-167 days preflight. Similar equipment was used in each 60-minute in-flight session (mean microgravity exposure--114 days [34--190]). On-orbit ultrasound (US) operators used an e-learning system within 24 hours of these sessions. Expert assistance was provided using US video downlink and two-way voice. Testing was repeated 5-16 days after landing. Separate ANOVA was used on each echocardiographic variable (n = 33). Within each ANOVA, three tests were made: (a) effect of mission phase (preflight, in-flight, postflight); (b) effect of echo technician (two technicians independently analyzed the data); (c) interaction between mission phase and technician.

RESULTS

Eleven rejections of the null hypothesis (mission phase or technician or both had no effect) were found that could be considered for possible follow up. Of these, eight rejections were for significant technician effects, not space flight. Three rejections of the null hypothesis (aortic valve time velocity integral, mitral E-wave velocity, and heart rate) were attributable to space flight but determine to not be clinically significant. No rejections were due to the interaction between technician and space flight.

CONCLUSION

Thus, we found no consistent clinically significant effects of long-duration space flight on echocardiographic variables of the given group of subjects.

Extreme musculo-skeletal ultrasound: training of non-physicians in the Arctic Circle

Objective

The purpose of this study was to compare if non-physician, inexperienced ultrasound subjects can take quality diagnostic images after watching a brief educational video and using reference cue cards (autonomous group) versus taking ultrasound images with expert guidance using a satellite connection.

Methods

Six non-medical, inexperienced ultrasound subjects from a rural area (Arctic Circle) obtained ultrasound images of target anatomic regions using a portable ultrasound device after receiving expert-guided training or autonomous training (educational video and cue cards). Real-time expert guidance was provided using an audiovisual tele-ultrasound connection with direct ultrasound video compression which was relayed to a remote expert via a secure satellite connection. The resultant images from all studies were blindly reviewed by imaging experts for determination of diagnostic adequacy.

Results

All of the examinations were completed in <15 min. The blinded expert identified 85.1% of autonomously acquired images and 86.2% of the images obtained by expert guidance to be of diagnostic quality; there was no statistical difference between the two groups (P = 0.6653).

Conclusion

Non-physician, inexperienced subjects can quickly educate themselves to retrieve diagnostic quality ultrasound images whether they are being expert-guided or trained autonomously.