Student ultrasound education - current views and controversies.

As an extension of the clinical examination and as a diagnostic and problem-solving tool, ultrasound has become an established technique for clinicians. A prerequisite for high-quality clinical ultrasound practice is adequate student ultrasound training. In light of the considerable heterogeneity of ultrasound curricula in medical studies worldwide, this review presents basic principles of modern medical student ultrasound education and advocates for the establishment of an ultrasound core curriculum embedded both horizontally and vertically in medical studies.

Endocavity Ultrasound Transducers: Why High-Level Disinfection Is Necessary.

As a medical imaging modality, ultrasound is used by a wide cross-section of practitioners including radiologists, obstetricians, gynecologists, gastroenterologists, urologists and cardiologists. The increasing popularity of ultrasound as a diagnostic tool is due not only to the ease of use and portability of systems, but also to the perceived safety aspect of the examination. This latter point needs to be examined. As with any reusable medical device, the ultrasound transducer, also known as a probe, could potentially be a vector for the transmission of pathogenic viruses and fungi between patients if not correctly disinfected after each use. This transmission risk is magnified for an endocavity transducer that has come in contact with the vagina, anal canal or oral cavity, as it could be contaminated with organisms transmitted by blood or mucosal, genital or rectal secretions. Based on the Spaulding system, transducers that come in contact with mucous membranes are classified as semi-critical devices that require high-level disinfection (HLD) after each patient procedure. This HLD process should eliminate all microorganisms except high numbers of bacterial endospores. Only a small number of countries worldwide have implemented transducer reprocessing guidelines that adhere to the Spaulding classification and recommend HLD for endocavity transducers. Overall, there is a lack of conformity among global health agencies regarding the use of HLD for endocavity transducers. This is primarily due to the perception that the infection transmission risk is negligible and that if an endocavity transducer has been covered with a single-use sheath for the procedure, then low-level disinfection provides sufficient protection against pathogen transmission. The objective of this study was to review the published risk of infection transmission from endocavity transducers. By highlighting the outbreaks and case reports that implicate pathogen transmission from transducers, we posit that HLD should be a global standard of practice for the reprocessing of endocavity transducers. It requires substantial time for national health administrations to develop and legislate new recommendations, and for practice changes to be accepted and implemented by healthcare providers. We recommend that Joint Commission International (JCI) and other equivalent organizations enforce the use of HLD of endocavity ultrasound transducers during their accreditation reviews.

Point-of-care ultrasound in obstetrics and gynecology.

BACKGROUND: The rapid technical development and portability of ultrasound systems over recent years has had a profound impact on the area of point-of-care-ultrasound (POCUS), both in general medicine and in obstetrics and gynecology. The use of POCUS enables the clinician to perform the ultrasound scan either at the medical office or the patient's bedside and used as an extension of the physical examination. Real-time images can immediately be correlated with the patient's symptoms, and any changes in a (critical) patient's condition can be more rapidly detected. POCUS IN OBGYN: POCUS is also suitable for time-critical scenarios, and depending on the situation and its dynamics, the course and results of any therapy may be observed in real time. POCUS should be considered to be a routine extension of practice for most OB/GYN clinicians as it can give immediate answers to what could be life-threatening situations for the mother and/or baby. With its proven usefulness, the applications and use of POCUS should be incorporated in teaching programs for medical students, OBGYN residents and emergency physicians.

Recommendations for the Cleaning of Endocavity Ultrasound Transducers Between Patients.

The COVID-19 pandemic highlighted the importance of infection prevention and control measures for all medical procedures, including ultrasound examinations. As the use of ultrasound increases across more medical modalities, including point-of-care ultrasound, so does the risk of possible transmission from equipment to patients and patients to patients. This is particularly relevant for endocavity transducers, such as trans-vaginal, trans-rectal and trans-oesophageal, which could be contaminated with organisms from blood, mucosal, genital or rectal secretions. This article proports to update the WFUMB 2017 guidelines which focussed on the cleaning and disinfection of trans-vaginal ultrasound transducers between patients.

The ultrasound use of simulators, current view, and perspectives: Requirements and technical aspects (WFUMB state of the art paper).

Simulation has been shown to improve clinical learning outcomes, speed up the learning process and improve learner confidence, whilst initially taking pressure off busy clinical lists. The World Federation for Ultrasound in Medicine and Biology (WFUMB) state of the art paper on the use of simulators in ultrasound education introduces ultrasound simulation, its advantages and challenges. It describes different simulator types, including low and high-fidelity simulators, the requirements and technical aspects of simulators, followed by the clinical applications of ultrasound simulation. The paper discusses the role of ultrasound simulation in ultrasound clinical training, referencing established literature. Requirements for successful ultrasound simulation acceptance into educational structures are explored. Despite being in its infancy, ultrasound simulation already offers a wide range of training opportunities and likely holds the key to a broader point of care ultrasound education for medical students, practicing doctors, and other health care professionals. Despite the drawbacks of simulation, there are also many advantages, which are expanding rapidly as the technology evolves.

The use of simulation in medical ultrasound: Current perspectives on applications and practical implementation (WFUMB state-of-the-art paper).

Simulation has been shown to improve clinical learning outcomes, speed up the learning process, and improve trainee confidence, while taking the pressure off initial face-to-face patient clinical areas. The second part of The World Federation for Ultrasound in Medicine and Biology state-of-the-art paper on the use of simulators provides a general approach on the practical implementation. The importance of needs assessment before developing a simulation-based training program is outlined. We describe the current practical implementation and critically analyze how simulators can be integrated into complex task scenarios to train small or large groups. A wide range of simulation equipment is available especially for those seeking interventional ultrasound training, ranging from animal tissue models, simple synthetic phantoms, to sophisticated high-fidelity simulation platforms using virtual reality. Virtual reality simulators provide feedback and thereby allow trainees to not only to practice their motor skills and hand eye coordination but also to interact with the simulator. Future developments will integrate more elements of automated assessment and artificial intelligence, thereby enabling enhanced realistic training experience and improving skill transfer into clinical practice.

World Federation for Ultrasound in Medicine Review Paper: Incidental Findings during Obstetrical Ultrasound.

Although the prevalence of incidental findings revealed during an obstetric ultrasound examination is low, the findings may include adnexal and cervical masses, uterine or urinary congenital malformations, free fluid in the pouch of Douglas or tortuous vessels (varices). Adnexal masses are the most common finding and vary in imaging characteristics. They are mainly unilateral, cystic masses with a low risk of malignancy that are treated conservatively. The International Ovarian Tumor Analysis scoring models may be helpful in differentiating benign from malignant masses. For those masses >5 cm, follow-up is recommended, and resection could be considered to avoid risk of torsion, rupture and hemorrhage, which may compromise pregnancy outcome. Uterine masses such as fibroids are commonly diagnosed early in the first trimester and should be followed up during pregnancy to evaluate any changes. Transabdominal and transvaginal ultrasound is the first-line test for the diagnosis of such incidentalomas; however, magnetic resonance ultrasound may have a useful role in excluding malignancy potential. As a result of their low frequency and the lack of good evidence, there are no specific guidelines on the management of incidentalomas detected at obstetric scans. Their management should follow the related general guidelines for ovarian, cervical and uterine masses, with individualized management depending on the pregnancy status.

COVID-19: Infection prevention and control guidance for all ultrasound practitioners.

The severe acute respiratory syndrome coronavirus (SARS-CoV-2), an enveloped virus, is the causative agent of the disease known as COVID-19 (coronavirus disease-2019). Proper infection prevention and control measures and good hygiene practices are essential to prevent spread of COVID-19 and protect both patients and the healthcare worker. These guidelines are relevant to all ultrasound practitioners and provides guidance on cleaning and disinfection of ultrasound equipment, the environment and PPE (protective personal equipment) during the COVID-19 outbreak in the Australasian region.

Analysis of the integrity of ultrasound probe covers used for transvaginal examinations.

BACKGROUND: Ultrasound probe covers should be used for any ultrasound procedure where there is contact with body fluids or mucous membranes. The type and quality of probe covers used in clinical practice differ widely and studies in the early 1990s showed that condoms were more superior for use with transvaginal examinations than commercial probe covers. Since then, although products have changed, there have been no further studies to assess the breakage rate of different probe covers. The objectives of this study were to assess the integrity of the most commonly used probe covers for transvaginal ultrasound examinations under clinical conditions and report the breakage rate. METHODS: The study was conducted in public and private hospitals and private practices. A total of 500 covers for each of 10 brands of commercial covers and condoms (latex and latex free) were distributed to ultrasound practitioners. The transvaginal ultrasound examination practice was unchanged except that all covers were placed in a container for assessment instead of discarding post ultrasound examination. All covers were collected and subjected to a water leak test. Covers that broke upon deployment onto the ultrasound probe prior to the ultrasound examination were recorded. All covers that were broken or had microtears or leaks were recorded as well as photographed. Statistical analysis was performed along with Chi-squared analysis of the data and significance considered at P < 0.05. RESULTS: None of the commercial covers broke upon deployment onto the ultrasound probe prior to ultrasound examination. A total of 5000 probe covers were examined post-transvaginal ultrasound examinations. The breakage rate for condoms ranged from 0.4% to 13% and for commercial covers 0-5%. Statistical analysis of the data by comparison of p-values revealed that the best performing group were the commercial non-latex probe covers and worst performing group were the non-latex condoms. CONCLUSION: The breakage rates for commercial covers were not as high as previously reported and do not break upon deployment onto the ultrasound probe. This is the first comprehensive study that thoroughly evaluated the integrity of commercial covers and condoms used for transvaginal ultrasound examination in a clinical setting, with regards to brand, numbers and types of covers assessed.

WFUMB position paper on the management incidental findings: adrenal incidentaloma.

Focal lesions of the adrenal glands are incidentally detected in approximately 5% of cases by modern imaging techniques. Fewer than 5% of these adrenal incidentalomas are malignant and approximately 10% have endocrine activity. Reliable differentiation of malignant versus benign and hormonally active versus nonfunctional adrenal incidentalomas significantly influences therapeutic management and the outcome of affected individuals. Therefore, each adrenal incidentaloma should undergo a standardized diagnostic work-up to exclude malignancy and endocrine activity. This position statement of the World Federation of Ultrasound in Medicine and Biology (WFUMB) summarizes the available evidence on the management of adrenal incidentaloma and describes efficient management strategies with particular reference to the role of ultrasound techniques.

Comparing the effectiveness of training course formats for point-of-care ultrasound in the third trimester of pregnancy.

INTRODUCTION: The availability of obstetric point-of-care ultrasound (PoCUS) services has been shown to improve pregnancy outcomes in regional and remote areas both in Australia and around the world. There is an increasing demand for efficient, cost-effective PoCUS courses for monitoring the fetus in the third trimester of pregnancy. AIM: To compare the effectiveness of targeted PoCUS courses provided for health professionals that assess the fetus during the third trimester of pregnancy. METHOD: The skill-teaching curriculum and competency outcomes of six obstetric PoCUS courses were compared. There were 55 learners with no prior ultrasound experience including 23 with English as a second language. Course duration ranged from 4 to 18 h, didactic lecture time up to 6 h and practical scanning sessions of 3-12 h. Learner/tutor ratio varied from 1:1 to 6:1. All courses included the teaching of knobology, image optimisation and probe manipulation. Practical sessions included supervised scanning of ultrasound phantoms and scanning women in the third trimester of pregnancy. The teaching outcomes that were assessed included image optimisation, determination of fetal lie, fetal heart rate, measuring the single deepest pocket of amniotic fluid, identifying the placental position and basic fetal biometry. The same pre- and post-course multiple choice test and course evaluation forms were used for every programme. RESULTS: All participants achieved the limited course objectives, regardless of the differences in the course formats. CONCLUSION: This study confirms that obstetric PoCUS courses can provide the initial basic knowledge and scanning skills required to perform limited scope third-trimester scanning.

Medical Ultrasound Disinfection and Hygiene Practices: WFUMB Global Survey Results.

As ultrasound technology rapidly evolves and is used more frequently in every area of medical diagnosis and treatment, it may be overlooked as a potential vector in the transmission of a health care-associated infection. A survey on disinfection and hygiene practice in medical ultrasound was disseminated via the World Federation for Ultrasound in Medicine and Biology (WFUMB) to its six member federations and associated ultrasound societies globally. One thousand twenty-nine responses were obtained across a broad range of ultrasound practitioners. A total of 76% of respondents used transducer covers every time to scan open wounds and 71% when blood and bodily fluids were present or for an interventional procedure. Approved high-level disinfectants are not always used, even when blood comes into contact with the transducer or after endocavity scans. Alcohol-based wipes were used by many respondents to clean both external transducers and endocavity transducers. Open-ended responses indicated that a large caseload hindered the time required for cleaning and that access to clear guidelines would be beneficial. Global survey results indicate that some users do not comply with disinfection practice, and there is a gap in knowledge on basic infection prevention and control education within the ultrasound unit. As the infectious status of a patient is not often disclosed prior to an ultrasound examination, training in suitable protocols for the cleaning and disinfection of ultrasound equipment is imperative to mitigate the risk of potential infection.

Advancing infection control in Australasian medical ultrasound practice.

INTRODUCTION/AIMS: Australasia is witnessing a rapidly increasing use of diagnostic medical ultrasound in clinical practice with industry statistics giving a conservative estimate of ten million scans performed annually in Australia and New Zealand. Ultrasound practice has broadened from its traditional use in radiology, obstetrics and gynaecology, vascular and cardiology specialties to embrace emergency medicine, rheumatology, midwifery, physiotherapy, paramedics and other point of care practice. With this expansion of practice comes an increase in the potential risk for ultrasound transmitted bacterial or viral infection due to suboptimal cleaning habits of transducers, cords and keyboards. RESULTS/CONCLUSION: This study describes results of an Australasian survey on the disinfection and hygiene practice in medical ultrasound. Results highlighted a significant need for updated guidelines and education on infection prevention and control in medical ultrasound.

Measuring leading placental edge to internal cervical os: Transabdominal versus transvaginal approach.

We aimed to compare the value of transabdominal (TA) and transvaginal (TV) approaches for assessing the risk of a low-lying placenta. This involved a comparison of TA and TV measurements between the leading placental edge and the internal cervical os. We also assessed the intra-/interobserver variation for these measurements and the efficacy of TA measures in screening for a low placenta. METHODOLOGY: Transabdominal and TV measurements of the leading placental edge to the internal cervical os were performed on 369 consecutive pregnancies of 16-41 weeks' gestation. The difference (TA-TV) from the mean was calculated and plotted against gestational age. Bland-Altman plots and paired t-tests were used to look at the differences in TA/TV measurement. Screening performance of a transabdominal approach was compared to a transvaginal 'gold standard'. Nonparametric methods were used to calculate the area under the receiver operator characteristics (ROC) curve. Intra-/interobserver variations were also calculated. RESULTS: Of the pregnancies, 278 had a leading placental edge that was visible with the TV approach. Differences (TA-TV) ranged from -50 mm to +57 mm. Bland-Altman plot shows that TA measurements overestimated the distance compared with the TV measurements; the average difference in measurement was 12.0 mm (95% confidence interval 9.9-14.1). The sensitivity, specificity and negative predictive values of a TA approach were 18.2%, 97.5% and 87.2%, respectively. The receiver operator characteristics area between gestational weeks 16-23 was 0.81 (95% CI: 0.76-0.86). CONCLUSION: The TA approach has a low sensitivity for detecting a low-lying placenta as choosing a TA cut-off with sensitivity >90% will decrease the specificity to 50%.

Potential Infection Control Risks Associated with Ultrasound Equipment - A Bacterial Perspective.

Ultrasound equipment used in trans-abdominal (TA) and trans-vaginal (TV) examination may carry bacterial contamination and pose risks to infection control during ultrasound examination. We aimed to describe the prevalence of bacterial contamination on ultrasound probes, gel, machine keyboard and cords and examined the effectiveness of low- and high-level disinfection techniques. This study was performed at a public hospital and a private practice. A total of 171 swabs were analyzed and bacterial species were identified using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) analysis and polymerase chain reaction (PCR). Sixty percent of TA probes and 14% of TV probes had evidence of bacterial contamination after an ultrasound examination. Low-level disinfection was partially effective, but 4% of probes were still contaminated by spore-forming species. Some heated gel samples were highly contaminated with the environmental bacterium Brevundimonas aurantiaca, suggesting the gel was conducive to bacterial growth. Ultrasound machines, probe cords and gels were identified as potential sources of bacterial contamination and need to be cleaned and changed regularly to minimize risks of infection.

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.

National survey of Australian sonographer knowledge and behaviour surrounding the ALARA principles when conducting the 11-14-week obstetric screening ultrasound.

OBJECTIVES: To identify gaps in Australian sonographer's knowledge and application of as low as reasonably achievable (ALARA) principles during first trimester imaging; Identify relationships between demographic variables and knowledge or application of the Output Display Standard (ODS) value thermal index (TI) and compare Australian sonographers to their international peers. METHODS: Australian Sonographer Accreditation Registered ( ASAR)-registered sonographers completed a voluntary questionnaire over September 2015 after institutional ethics approval (RDSE-48-15). Seventeen questions detailed their demographics (5); knowledge of ultrasound bioeffects terminology and ALARA principles (9); behaviour surrounding ALARA and first trimester imaging (2) and continuing bioeffects education (1). Exclusion criteria was non-ASAR status. Descriptive (mode frequency) and inferential statistics (Fisher exact test) were used. Significance level was 95%. RESULTS: Ninety-five valid surveys were collected. Ninety-nine per cent knew the meaning of ALARA, 93.55% correctly defined 'TI' and 85.39% knew where to find the TI value via the ODS. Half never monitor the ODS. No correlation (P = 0.094) was found between experience and ODS monitoring. No statistical difference (P = 0.189) existed between obstetric and non-obstetric sonographers who knew the meaning of TIB (87.18% vs. 76.92%) or those who correctly identified it as the setting for 11-14-week examinations (30.77% vs. 30.77%). When using Doppler during obstetric examinations, no difference existed (P = 0.293), between obstetric and non-obstetric sonographers' knowledge of ASUM/WFUMB guidelines for maximum TI (47.37% vs. 46.15%). CONCLUSIONS: Despite poor ODS usage, Australian sonographers outperform their international peers for ALARA literacy, and show better application of ALARA principles in the first trimester. No relationships were found between demographic variables and knowledge or conscious monitoring of ODS.

Cervical length measurement: Comparison of transabdominal and transvaginal approach.

Objective: To compare transabdominal (TA) and transvaginal (TV) ultrasound assessment of cervical length at 16-41 weeks gestation. Methods: TA and TV ultrasound measurements of cervical length were made on 491 pregnancies of 16-41 weeks gestation. Cervical length was measured from internal to external cervical os. Bland-Altman plots and Wilcoxon signed rank test were used to evaluate differences between TA and TV measurements. Results: The validity of the TA method depended on cervical length. Although the TA method underestimated cervical length by 2.0 mm on average (P < 0.001), Bland Altman plots showed an inverse trend with shorter cervixes. In women with a cervix < 25 mm (n = 30) based on TV scan measurement, TA overestimated cervical length by 12 mm (P < 0.001). The sensitivity and specificity of TA as a test to detect cervical length < 25 mm were 10% (95% CI: 2.1-26%) and 94% (95% CI: 92-96%) respectively; the negative LR was 0.96 (95% CI: 0.84-1.08). The maximum area under the ROC curve would be obtained at a TA cut-off = 32 mm (to detect a cervix < 25 mm), corresponding to a sensitivity of 77% and a specificity of 58%. Conclusion: TA measurements do not reflect TV assessment accurately, particularly if the cervix is short. At 24-34 weeks, a policy of proceeding to TV scan if TA measurement is < 25 mm will only detect 10% of affected pregnancies and has a poor positive predictive value so is of limited value as a predictive tool for women attending with symptoms and signs of preterm labour > 24 weeks gestation. There is no value in TA assessment of the cervix > 36 weeks.

Estimating fetal weight for best clinical outcome.

Clinical decisions are often based on the results of third trimester sonograms, particularly with small or large babies and so accuracy of estimating fetal weight (EFW) is essential. There are numerous EFW formula available and yet in Australia no one formula has been recommended for use due to the lack of clinical evidence as to their accuracy. Objectives: 1 To assess inter/intra observer error for fetal parameter measurements with multiple observers. 2 To compare six of the most commonly used EFW formulae and analyse inter/intra formulae variations for different weight range. Method: EFW of 121 pregnancies assessed within 7 days of birth by measuring the BPD, OFD, HC, AC, FL and comparing to actual birth weight. Results: Inter-observer error: 1.3 to 3.1%. Intra-observer error: 1.1 to 1.9% depending on fetal parameter. Accuracy of each EFW formula changed with different weight ranges. For all formulae the highest random error occurred in the macrosomic group. The lowest random error in all weight groups was the Hadlock B formula incorporating the HC/AC/FL (7.7%). Conclusion: Considering the possible problems of head moulding this study suggests the use of: Hadlock FP et al (1982) - Formula B - incorporating HC/AC/FL.