Emergency Thoracic US: The Essentials

Automated detection and segmentation of pleural effusion on ultrasound images using an Attention U-net

BACKGROUND

Ultrasonic for detecting and evaluating pleural effusion is an essential part of the Extended Focused Assessment with Sonography in Trauma (E-FAST) in emergencies. Our study aimed to develop an Artificial Intelligence (AI) diagnostic model that automatically identifies and segments pleural effusion areas on ultrasonography.

METHODS

An Attention U-net and a U-net model were used to detect and segment pleural effusion on ultrasound images of 848 subjects through fully supervised learning. Sensitivity, specificity, precision, accuracy, F1 score, the receiver operating characteristic (ROC) curve, and the area under the curve (AUC) were used to assess the model's effectiveness in classifying the data. The dice coefficient was used to evaluate the segmentation performance of the model.

RESULTS

In 10 random tests, the Attention U-net and U-net 's average sensitivity of 97% demonstrated that the pleural effusion was well detectable. The Attention U-net performed better at identifying negative images than the U-net, which had an average specificity of 91% compared to 86% for the U-net. Additionally, the Attention U-net was more accurate in predicting the pleural effusion region because its average dice coefficient was 0.86 as opposed to the U-net's average dice coefficient of 0.82.

CONCLUSIONS

The Attention U-net showed excellent performance in detecting and segmenting pleural effusion on ultrasonic images, which is expected to enhance the operation and application of E-FAST in clinical work.

Point-of-Care Lung Ultrasound in the Intensive Care Unit-The Dark Side of Radiology: Where Do We Stand?

Patients in intensive care units (ICUs) are critically ill and require constant monitoring of clinical conditions. Due to the severity of the underlying disease and the need to monitor devices, imaging plays a crucial role in critically ill patients' care. Given the clinical complexity of these patients, who typically need respiratory assistance as well as continuous monitoring of vital functions and equipment, computed tomography (CT) can be regarded as the diagnostic gold standard, although it is not a bedside diagnostic technique. Despite its limitations, portable chest X-ray (CXR) is still today an essential diagnostic tool used in the ICU. Being a widely accessible imaging technique, which can be performed at the patient's bedside and at a low healthcare cost, it provides additional diagnostic support to the patient's clinical management. In recent years, the use of point-of-care lung ultrasound (LUS) in ICUs for procedure guidance, diagnosis, and screening has proliferated, and it is usually performed at the patient's bedside. This review illustrates the role of point-of-care LUS in ICUs from a purely radiological point of view as an advanced method in ICU CXR reports to improve the interpretation and monitoring of lung CXR findings.

Failure to receive prescribed imaging is associated with increased early mortality after injury in Cameroon

Despite having the highest rates of injury-related mortality in the world, trauma system capacity in sub-Saharan Africa remains underdeveloped. One barrier to prompt diagnosis of injury is limited access to diagnostic imaging. As part of a larger quality improvement initiative and to assist priority setting for policy makers, we evaluated trauma outcomes among patients who did and did not receive indicated imaging in the Emergency Department (ED). We hypothesize that receiving imaging is associated with increased early injury survival. We evaluated patterns of imaging performance in a prospective multi-site trauma registry cohort in Cameroon. All trauma patients enrolled in the Cameroon Trauma Registry (CTR) between 2017 and 2019 were included, regardless of injury severity. Patients prescribed diagnostic imaging were grouped into cohorts who did and did not receive their prescribed study. Patient demographics, clinical course, and outcomes were compared using chi-squared and Kruskal-Wallis tests. Multivariate logistic regression was used to explore associations between radiologic testing and survival after injury. Of 9,635 injured patients, 47.5% (4,574) were prescribed at least one imaging study. Of these, 77.8% (3,556) completed the study (COMPLETED) and 22.2% (1,018) did not receive the prescribed study (NC). Compared to COMPLETED patients, NC patients were younger (p = 0.02), male (p<0.01), and had markers of lower socioeconomic status (SES) (p<0.01). Multivariate regression adjusted for age, sex, SES, and injury severity demonstrated that receiving a prescribed study was strongly associated with ED survival (OR 5.00, 95% CI 3.32-7.55). Completing prescribed imaging was associated with increased early survival in injured Cameroonian patients. In a resource-limited setting, subsidizing access to diagnostic imaging may be a feasible target for improving trauma outcomes.

New International Guidelines and Consensus on the Use of Lung Ultrasound

Following the innovations and new discoveries of the last 10 years in the field of lung ultrasound (LUS), a multidisciplinary panel of international LUS experts from six countries and from different fields (clinical and technical) reviewed and updated the original international consensus for point-of-care LUS, dated 2012. As a result, a total of 20 statements have been produced. Each statement is complemented by guidelines and future developments proposals. The statements are furthermore classified based on their nature as technical (5), clinical (11), educational (3), and safety (1) statements.

Ultrasonography in the Evaluation of Pediatric Chest "Masses": When to Consider?

Thoracic ultrasound is radiation-free, easily available, portable modality with added advantage of real-time assessment. It is useful in mediastinal lesions and peripheral lung, pleural and chest wall masses. Not only is it a valuable modality in differentiating solid from cystic lesion, it can also depict internal architecture without the use of contrast material. The added advantages of its use in children are the lack of ionizing radiation, and no need for sedation or general anesthesia in most cases. Although it has its limitations with a longer learning curve, it can act as a second-line modality to chest radiograph and adjunctive modality to CT in cases of a thoracic mass in a child.

Radiology and A Radiologist: A Keystone in the Turmoil of Trauma Setting

Traumatic injuries are one of the leading causes of morbidity and mortality. Precise diagnosis and management in the golden hour are key to decrease morbidity and mortality. History and physical examination alone are insufficient to avoid misdiagnosis. In this article, we tried to determine the role of a radiologist and an appropriate imaging modality in a trauma setting. We conducted a literature review of published research articles. We used the keywords imaging, trauma, imaging and trauma, and trauma imaging essentials were used on PubMed and Google Scholar. The articles published in the English language from 2015 to 2020 with full free text available were included. Using the medical subject heading (MeSH) strategy, "diagnostic imaging" (Major {Majr}) and "multiple trauma/diagnostic imaging" (Mesh) on PubMed, we identified 34 papers after applying the inclusion and exclusion criteria. Twenty articles were finally selected which included studies from 2015 to 2020 with articles focusing on the adult population and acute cases. A radiologist and imaging modalities are the essential parts of a trauma setting to lower morbidity and mortality. X-rays and Extended Focussed Assessment with Sonography for Trauma (eFAST) are the first-line imaging modality in the acute trauma setting. However, the CT scan is the most sensitive modality that should be done to avoid misdiagnosis depending upon the patient's history and physical examination.

Diagnostic accuracy of a lung ultrasound protocol (Vet BLUE) for detection of pleural fluid, pneumothorax and lung pathology in dogs and cats

OBJECTIVES

To assess the accuracy of the lung ultrasound protocol Vet BLUE, using thoracic CT as the reference standard, for the detection of thoracic pathology in dogs and cats.

MATERIALS AND METHODS

Animals that had thoracic ultrasound and thoracic CT were prospectively recruited between May 2017 and September 2018. The Vet BLUE protocol was performed on animals at the time of admission by veterinarians with basic training in emergency ultrasound. A board-certified radiologist, blinded to the Vet BLUE findings, reviewed the CT images.

RESULTS

CT was abnormal in 64.5% (20/31) animals. The number of CT sites positive for alveolar-interstitial syndrome was 24.2% (60/248). When using CT as the reference standard, detection of ≥3 B lines with thoracic ultrasound had a sensitivity of 18.33% and specificity of 98.4% for detection of site specific alveolar-interstitial syndrome. The sensitivity of Vet BLUE to detect alveolar-interstitial syndrome increased to 56.9% when including the presence of any B line as abnormal. Overall accuracy for detection of alveolar-interstitial syndrome based on these two criteria was 79% and 73%, respectively. Vet BLUE correctly identified consolidation in 58.3% (14/24) sites, pleural effusion in 66.6% (2/3) cases, pneumothorax in 33.3% (1/3) cases and intrathoracic mass in 25% (1/4) cases.

CLINICAL SIGNIFICANCE

The Vet BLUE protocol is a useful technique to detect alveolar-interstitial syndrome and other thoracic pathology but should not be used as a sole imaging method. Detection of ≥3 B lines is highly suggestive of alveolar-interstitial syndrome and warrants further diagnostics.

Point-of-Care Ultrasound in Acute Care Nephrology

The use of point-of-care ultrasound (POCUS) is rapidly increasing in nephrology. It provides the opportunity to obtain complementary information that is more accurate than the classic physical examination. One can quickly follow the physical examination with a systematic POCUS evaluation of the kidneys, ureter bladder, inferior vena cava, heart, and lungs, which can provide diagnostic information and an accurate assessment of the patient's hemodynamics and volume status. Moreover, because it is safe and relatively easy to perform, it can be performed in a repeated manner as often as necessary so that the physician can reassess the patient's hemodynamics and volume status and adjust their therapy accordingly, permitting a more personalized approach to patient care (rather than blindly following protocols), especially to patients in acute care nephrology. Despite these advantages, nephrologists have been slow to adopt this diagnostic modality, perhaps because of lack of expertise. This review will provide an overview of the most commonly used POCUS examinations performed by nephrologists in the acute care setting. Its aim is to spark interest in in POCUS and to lay the foundation for readers to pursue more advanced training so that POCUS becomes a readily available tool in your diagnostic arsenal.

The role of point of care ultrasound in radiology department: update and prospective. A statement of Italian college ultrasound

Ultrasound, in its new point-of-care conception, has been called the stethoscope of the future. Goal-directed bedside ultrasound examination, performed by a healthcare provider to answer a specific diagnostic question or guide an invasive procedure, is currently revolutionizing medical practice. It is used by various specialties in multiple clinical contexts for procedural, diagnostic, and screening applications. Point-of-care ultrasound is also a strategic technique in clinical radiology; it brings the radiologist closer to the patient (in interaction and understanding) like interventional and angiography procedures and, as an integrative imaging modality, is a vital radiological tool for decision-making in many situations. In this commentary, we present our observations on the use of ultrasound, in a sincere appeal to refrain from omitting ultrasound as a diagnostic technique in this era of deep professional change, in which radiologists must return to being a true clinical semiologist.

How to perform and interpret the lung ultrasound by the obstetricians in pregnant women during the SARS-CoV-2 pandemic

Objective:

Evidence for the use of lung ultrasound scan (LUS) examinations in coronavirus 2019 pneumonia is rapidly growing. The safe and non-ionizing nature of LUS drew attention, particularly for pregnant women. This study aimed to contribute to the interpretation of LUS findings in pregnant women for the obstetricians.

Materials and Methods:

LUS was performed to pregnant women suspected of or diagnosed as having Severe Acute Respiratory syndrome coronavirus-2 (SARS-CoV-2) in the first 24 hours of admission. Fourteen areas (3 posterior, 2 lateral, and 2 anterior) were scanned per patient for at least 10 seconds along the indicated anatomical landmarks. The scan was performed in supine, right-sided and left-sided positions, respectively. Each area was given a score between 0 and 3 according to the specific pattern.

Results:

In this study, 21 still images and 21 videoclips that enabled dynamic and real-time evaluation were provided. Pleural line assessment, physiologic A-lines, pathologic B-lines, light beam pattern, white lung pattern, and specific patterns for quick recognition and evaluation are described.

Conclusion:

The potential advantages and limitations of LUS and its areas of use for obstetricians are discussed. LUS is a promising supplementary imaging tool during the SARS-CoV-2 pandemic. It is easy to perform and may be feasible in the hands of obstetricians after a brief didactic course. It may be a firstline imaging modality for pregnant women.

Imaging findings in COVID-19 pneumonia

The coronavirus disease (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in Wuhan city and was declared a pandemic in March 2020. Although the virus is not restricted to the lung parenchyma, the use of chest imaging in COVID-19 can be especially useful for patients with moderate to severe symptoms or comorbidities. This article aimed to demonstrate the chest imaging findings of COVID-19 on different modalities: chest radiography, computed tomography, and ultrasonography. In addition, it intended to review recommendations on imaging assessment of COVID-19 and to discuss the use of a structured chest computed tomography report. Chest radiography, despite being a low-cost and easily available method, has low sensitivity for screening patients. It can be useful in monitoring hospitalized patients, especially for the evaluation of complications such as pneumothorax and pleural effusion. Chest computed tomography, despite being highly sensitive, has a low specificity, and hence cannot replace the reference diagnostic test (reverse transcription polymerase chain reaction). To facilitate the confection and reduce the variability of radiological reports, some standardizations with structured reports have been proposed. Among the available classifications, it is possible to divide the radiological findings into typical, indeterminate, atypical, and negative findings. The structured report can also contain an estimate of the extent of lung involvement (e.g., more or less than 50% of the lung parenchyma). Pulmonary ultrasonography can also be an auxiliary method, especially for monitoring hospitalized patients in intensive care units, where transfer to a tomography scanner is difficult.

The lung ultrasound: facts or artifacts? In the era of COVID-19 outbreak

Ultrasound is the most disruptive innovation in intensive care life, above all in this time, with a high diagnostic value when applied appropriately. In recent years, point-of-care lung ultrasound has gained significant popularity as a diagnostic tool in the acutely dyspnoeic patients. In the era of Sars-CoV-2 outbreak, lung ultrasound seems to be strongly adapting to the follow-up for lung involvement of patients with ascertaining infections, till to be used, in our opinion emblematically, as a screening test in suspected patients at the emergency triage or at home medical visit. In this brief review, we discuss the lung ultrasound dichotomy, certainties and uncertainties, describing its potential role in validated clinical contexts, as a clinical-dependent exam, its limits and pitfalls in a generic and off-label clinical context, as a virtual anatomical-dependent exam, and its effects on the clinical management of patients with COVID-19.

From bedside to bench: lung ultrasound for the assessment of pulmonary edema in animal models

Traditionally, the lung has been excluded from the ultrasound organ repertoire and, hence, the application of lung ultrasound (LUS) was largely limited to a few enthusiastic clinicians. Yet, in the last decades, the recognition of the previously untapped diagnostic potential of LUS in intensive care medicine has fueled its widespread use as a rapid, non-invasive and radiation-free bedside approach with excellent diagnostic accuracy for many of the most common causes of acute respiratory failure, e.g., cardiogenic pulmonary edema, pneumonia, pleural effusion and pneumothorax. Its increased clinical use has also incited attention for the potential usefulness of LUS in preclinical studies with small animal models mimicking lung congestion and pulmonary edema formation. Application of LUS to small animal models of pulmonary edema may save time, is cost-effective, and may reduce the number of experimental animals due to the possibility of serial evaluations in the same animal as compared with traditional end-point measurements. This review provides an overview of the emerging field of LUS with a specific focus on its application in animal models and highlights future perspectives for LUS in preclinical research.

The imaging appearances of various pericardial disorders

The pericardium could be involved in a variety of clinical disorders. The imaging findings are not specific for an individual pathology in most of the cases; however, patient’s clinical history may guide radiologist to a definitive diagnosis. Congenital absence of the pericardium could be recognized with the imaging appearance of interposed lung tissue between the main pulmonary artery and aorta. Pericardial effusion is a non-specific condition that may occur due to inflammatory, infectious, and neoplastic disorders. Cardiac tamponade may occur in case of massive or rapid accumulation of fluid in the pericardial sac. Pericardial calcification is a common and easily identified entity on a computed tomography (CT) scan. Presence of calcification and/or fibrosis may result in pericardial constriction. Nevertheless, the pulsation of an adjacent coronary artery may prevent calcification formation in a focal area and consequently may result in pericardial diverticulum containing epicardial fat and coronary artery. The imaging findings encountered in patients with pericardial hydatid disease and Erdheim-Chester disease may mimic those of pericardial neoplasia. Pericardial adhesions and pedicled fat flaps may cause confusion on a CT scan in the post-surgical period following cardiac surgery. Pericardial fat necrosis can be diagnosed by CT in patients with chest pain. The radiologists should be familiar with the medical devices placed in pericardial space for certain individual indications. A pericardial patch and temporary epicardial pacemaker wires could be identified on a CT scan.

Competence in thoracic ultrasound

Ultrasound examination is traditionally considered a safe and repeatable exam, but its use is highly operator-dependent. Because of this, lack of sufficient operator skills could lead to diagnostic errors and damage to patient safety related to unnecessary tests or interventional procedures. The indications for lung ultrasound include: diagnosis, quantification, and follow-up of different conditions for which acute respiratory failure or chest pain are the main clinical presentation. Clinicians should have theoretical and practical knowledge on: physics and technology of ultrasound, indications and methodology of ultrasound examination, normal thoracic anatomy identification by echography, and detection of signs of pleuro-pulmonary pathology. Consequently, according to international recommendations, core basic skills and minimum training recommendations for the practice of medical ultrasound and image acquisition are needed to ensure competence of clinicians using ultrasound.

Perioperative ultrasound-assisted clinical evaluation - A case based review

Ultrasound is increasingly being adopted into anaesthesia and intensive care practice. The range of ultrasound examination has also increased from transoesophageal echocardiography in cardiac surgery and ultrasound-guided nerve blocks and vascular access, to examination of the heart, lungs, abdomen and deep veins. Typically, the use of ultrasound is focused or basic, designed to be performed by the anaesthetist at the patient's bedside in real time to answer clinical questions and to direct therapy. Ultrasound is not performed in isolation, but used to complement clinical evaluation, and accordingly can be considered as 'ultrasound-assisted perioperative evaluation'. Whilst there is good evidence that ultrasound improves diagnostic accuracy and in turn alters management, there are few data examining whether ultrasound leads to improved clinical outcomes. This review will examine multiple uses of perioperative ultrasound with case studies to illustrate potential utility.

Chest Ultrasonography in Modern Day Extreme Settings: From Military Setting and Natural Disasters to Space Flights and Extreme Sports

Chest ultrasonography (CU) is a noninvasive imaging technique able to provide an immediate diagnosis of the underlying aetiology of acute respiratory failure and traumatic chest injuries. Given the great technologies, it is now possible to perform accurate CU in remote and adverse environments including the combat field, extreme sport settings, and environmental disasters, as well as during space missions. Today, the usage of CU in the extreme emergency setting is more likely to occur, as this technique proved to be a fast diagnostic tool to assist resuscitation manoeuvres and interventional procedures in many cases. A scientific literature review is presented here. This was based on a systematic search of published literature, on the following online databases: PubMed and Scopus. The following words were used: "chest sonography," " thoracic ultrasound," and "lung sonography," in different combinations with "extreme sport," "extreme environment," "wilderness," "catastrophe," and "extreme conditions." This manuscript reports the most relevant usages of CU in the extreme setting as well as technological improvements and current limitations. CU application in the extreme setting is further encouraged here.

Focused assessment with sonography for trauma: current perspectives

Focused assessment with sonography for trauma (FAST) is a part of resuscitation of trauma patients recommended by international panel consensus. The purpose of FAST is to identify free fluid, which necessarily means blood in acute trauma patients. In this article, the authors focused on various aspects of FAST in the emergency department, prehospital care, pediatric setting, training and general pearls/pitfalls. Detailed techniques and interpretation of FAST are beyond the scope of this article.

Advances in lung ultrasound

Ultrasound examination of the chest has advanced in recent decades. This imaging modality is currently used to diagnose several pathological conditions and provides qualitative and quantitative information. Acoustic barriers represented by the aerated lungs and the bony framework of the chest generate well-described sonographic artifacts that can be used as diagnostic aids. The normal pleural line and A, B, C, E and Z lines (also known as false B lines) are artifacts with specific characteristics. Lung consolidation and pneumothorax sonographic patterns are also well established. Some scanning protocols have been used in patient management. The Blue, FALLS and C.A.U.S.E. protocols are examples of algorithms using artifact combinations to achieve accurate diagnoses. Combined chest ultrasonography and radiography are often sufficient to diagnose and manage lung and chest wall conditions. Chest ultrasonography is a highly valuable diagnostic tool for radiologists, emergency and intensive care physicians.

Thoracic Ultrasound: Technique, Applications, and Interpretation

Thoracic ultrasound is used at the bedside in emergency and critical care settings. Advantages of ultrasound include rapid real-time, low-cost, diagnostic information that can direct patient care without the use of ionizing radiation. We describe methods on how to perform lung ultrasound, with the intent to educate the radiologist who might otherwise be relatively unfamiliar with thoracic sonography. We describe and depict the normal sonographic appearance of lung anatomy. We also show the sonographic appearance of a wide range of lung and pleural pathologies such as pneumonia, pneumothorax, as well as lung and pleural masses. We review various lines and signs described in the literature, such as A-lines, B-lines, the stratosphere sign, and the bat-wing sign. Finally, we correlate our findings with chest x-ray and computerized tomography to emphasize the anatomy.

Pleural ultrasound for clinicians

Pleural ultrasonography is useful for identifying and characterising pleural effusions, solid pleural lesions (nodules, masses, swellings) and pneumothorax. Pleural ultrasonography is also considered the standard care for guiding interventionist procedures on the pleura at the patient's bedside (thoracentesis, drainage tubes, pleural biopsies and pleuroscopy). Hospitals should promote the acquisition of portable ultrasound equipment to increase the patient's safety.