Role of dynamic ultrasound in assessment of the snapping elbow and distal biceps tendon injury

Introduction Ultrasound is useful in assessing patients with snapping syndromes around the elbow joint. The dynamic nature of the examination allows for direct visualisation of the underlying causative factor. Topic description: We discuss the role of dynamic ultrasound in assessing various snapping syndromes around the elbow, such as ulnar nerve instability, snapping triceps and less commonly, snapping brachialis. Ultrasound is also useful in evaluating the distal biceps tendon, particularly in differentiating partial from complete tendon injury. Discussion Ulnar nerve instability and snapping triceps can be assessed via a medial approach with the transducer placed transversely between the medial epicondyle and the olecranon. In ulnar nerve instability, the nerve can be seen crossing over the medial epicondyle on elbow flexion. In snapping triceps syndrome, both the ulnar nerve and the distal triceps can be seen dislocating over the medial epicondyle. Dynamic assessment of the distal biceps tendon using a lateral approach minimises anisotropy artefact often seen on the anterior approach. Passive pronation and supination of the forearm will reveal little or no movement in a completely torn tendon whereas moving tendon fibres will be appreciated in partial tears. In a snapping brachialis, the medial portion of brachialis will be seen abnormally translocating anterolateral to the medial border of the trochlea during elbow flexion and snapping back into its normal position on elbow extension. Conclusion Dynamic ultrasound of the elbow is valuable in diagnosing patients with snapping sensations around the joint and in evaluating the integrity of the distal biceps tendon.

Entrapment of the index finger radial collateral ligament in the metacarpophalangeal joint: A case report

Introduction Digital collateral ligament injuries are common hand injuries that can cause significant pain and functional impairment. Ultrasonography can be useful in the evaluation of these ligamentous injuries, as it is both cost-effective and allows for easy, dynamic evaluation during imaging. Case report We report a rare sonographic finding of an index finger radial collateral ligament injury that was found to have a flap of the ligament entrapped within the metacarpophalangeal joint, which to our knowledge has not been described previously. We correlate this finding with an intraoperative image of the entrapment of the collateral ligament. We also report on the novel application of superb microvascular imaging to aid in the diagnosis of digital collateral ligament injury. Discussion This particular injury pattern has not been reported in the literature previously and likely explains the patient’s lack of improvement with nonoperative management. Our finding is similar to a Stener lesion seen in a thumb ulnar collateral ligament injury in which the ligament is unable to heal due to entrapment. In addition, using superb microvascular imaging (SMI), we were able to visualize hyperemia to surrounding structures and the ligament itself which suggested an acute injury. Conclusion We anticipate that this case report will provide sonographers with knowledge and images of this specific injury pattern to the digital collateral ligaments.

Aberrant right subclavian artery: embryology, prenatal diagnosis and clinical significance

Introduction The right subclavian artery normally arises as the first vessel from the brachiocephalic trunk. An aberrant right subclavian artery (ARSA) arises directly from the aortic arch and crosses behind the trachea towards the right arm. This variant occurs in approximately 1–2% of the population; however, the frequency increases in individuals with chromosomal abnormalities such as trisomy 21 and 22q11.2 microdeletion. Prenatal identification of ARSA therefore has a role in screening for such conditions. Methods Databases were searched for studies reporting the prenatal ultrasound evaluation of ARSA and its frequency in normal fetuses and in those with chromosomal abnormalities. Results A total of 23 studies were evaluated. Feasibility for the ultrasound evaluation of ARSA was 85–95%. The sonographic detection of ARSA is best in the three-vessel trachea view; however, sagittal and coronal imaging of the aortic arch may be useful. ARSA in isolation was not found to be associated with chromosomal abnormalities. The prevalence of ARSA in chromosomally abnormal fetuses was up to 24-fold higher than in normal fetuses, but the majority of chromosomally abnormal fetuses with ARSA had additional abnormal ultrasound findings, particularly cardiac abnormalities. Conclusions The prenatal detection of ARSA is a clinically useful prenatal marker for chromosomal abnormalities. In isolation, it is unlikely to be associated with pathogenic genetic variants. The ultrasound diagnosis of ARSA should prompt meticulous assessment of associated abnormalities. Invasive diagnostic testing should be offered to patients with non-isolated ARSA or in the presence of non-reassuring screening results or other risk factors.

Point-of-care contrast enhanced lung ultrasound and COVID-19

Objectives Bedside lung ultrasound has been indispensable during the coronavirus disease 2019 (COVID-19) pandemic, allowing us to rapidly assess critically unwell patients. We demonstrate the unique application of contrast-enhanced ultrasound with the aim of further understanding this disease. Methods Patient demographics were recorded alongside recent cross-sectional imaging and inflammatory markers. Ultrasound was conducted by experienced operators in a portable setting. Conventional six-point lung ultrasound method was used to evaluate B-lines, small (subpleural) consolidation and the pleura. Areas of small consolidation were targeted after intravenous administration of ultrasound contrast. Results The areas of small consolidations, a potential sign of pneumonia on B-mode lung ultrasound, usually enhance on contrast-enhanced ultrasound. Our study revealed these areas to be avascular, indicating an underlying thrombotic/infarction process. Findings were present in 100% of the patients we examined. We have also shown that the degree of infarction correlates with CT severity (r = 0.4) and inflammatory markers, and that these areas improve as patients recover. Conclusions We confirmed the theory of immune thrombus by identifying the presence of microthrombi in the lungs of 100% of our patients, despite 79% having had a recent negative CT pulmonary angiogram study. contrast-enhanced ultrasound can be utilised to add confidence to an uncertain COVID-19 diagnosis and for prognosticating and monitoring progress in confirmed COVID-19 patients. Contrast-enhanced ultrasound is clearly very different to CT, the gold standard, and while there are specific pathologies that can only be detected on CT, contrast-enhanced ultrasound has many advantages, most notability the ability to pick up microthrombi at the periphery of the lungs.

Supradiaphragmatic central venous catheter malposition detection using the parasternal long-axis echocardiographic view and dextrose 50% contrast solution: A pilot study

Background Contrast-enhanced ultrasonography (CEUS) using saline was studied to detect supradiaphragmatic central venous catheter malposition. Commonly used echocardiographic views are apical 4-chamber (A4c) and subcostal views. However, this standard method is not feasible in certain situations. We explored the feasibility of the right ventricle inflow parasternal long axis (RVI-PLAX) echocardiographic view and dextrose 50% (D50%) contrast solution for detecting supradiaphragmatic central venous catheter malposition. Method This pilot study screened 60 patients who underwent ultrasound-guided supradiaphragmatic central venous catheter insertion. We compared the investigators' guidewire's J-tip detection, D50% rapid atrial swirl sign (RASS) findings on the RVI-PLAX view and the central venous catheter tip on chest radiograph. We also compared the mean capillary blood sugar level before and after the 5 ml D50% flush. Results No guidewire J-tips were detected from the RVI-PLAX view. The first and second investigators’ diagnosis of central venous catheter malposition detected on RVI-PLAX CEUS achieved an almost perfect agreement (κ = 1.0 (95% confidence interval (CI): 0.90 to 1.0), p < .0001). The RVI-PLAX CEUS was not able to detect two central venous catheter malpositions (one atrial malposition and one left brachiocephalic vein venous catheter malposition). The capillary blood sugar was significantly elevated (8.96 mmol/L vs. 9.75 mmol/L) after D50% flush ( p < 0.005) with no complications reported within 30 minutes after the D50% flush. Conclusion RVI-PLAX view should not be used for guidewire detection. CEUS using D50% and RVI-PLAX view are potentially useful tools in detecting central venous catheter malposition. Further studies comparing them with conventional methods are needed.

A snapshot of venous ultrasound examinations in Australia and New Zealand: Implications for diagnosis and management of chronic venous disease interventions

Objective Chronic venous disease is a common vascular condition, affecting up to 60% of the population worldwide. In Australia and New Zealand, chronic venous insufficiency ultrasound examinations are primarily performed by sonographers. This research aimed to explore how ultrasound examinations are being performed, providing insights into current practices and recommendations for quality improvement. Method A questionnaire was distributed to capture demographics, practices of ultrasound, examination techniques, the use of nomenclature and experience of the respondents. Results The analysis of 97 responses showed a heterogeneity in the clinical application of ultrasound. Most sonographers performed less than two scans per day within 30–45 minutes. Deep venous incompetence was routinely excluded by all respondents. The majority used standing, sitting and reverse Trendelenburg position except for a few using supine position. Manual augmentation was the preferred provocation manoeuvre. Anatomical variations at the junctional level were not adequately evaluated. Although Giacomini’s vein was assessed by 80%, 57% of those did not evaluate paradoxical reflux. Seventy-five per cent routinely assessed non-saphenous reflux; however, over 50% were unfamiliar with lymph node venous networks. A significant number of out-dated venous terms were still being used. A low participation rate in continuing professional development was identified, which might be attributable to limited education and training programs. Conclusion The study is a multi-faceted exploration that identified a need for standardized diagnostic and reporting guidelines. Our results could explain discrepancies in diagnostic findings and inconsistencies in the use of medical terminology, with implications for clinical decision making and assessment of surgical outcome.

Urinary tract obstruction: Ultrasound-guided intervention

Introduction Urinary tract obstruction (UTO) is a common clinical problem of which there are many potential causes. The aim of this feature article is to explore the role of ultrasound in diagnosing UTO, during guided interventional procedures and the potential procedural complications. Topic description and discussion: Ultrasound is an integral imaging modality throughout the management pathway of a patient with UTO and is often utilised as a first-line test in diagnosis and treatment. Percutaneous nephrostomy is an interventional technique, usually performed by radiologists or interventional sonographers, as either a short- or long-term management strategy. It can either be used in isolation or to gain access to the renal collecting system prior to more complex interventional or surgical techniques. Ultrasound-guided interventional techniques to relieve UTO can be employed in a number of clinical scenarios each with their own indications, contraindications and complications. Conclusion Ultrasound plays a unique role in the planning and active stages of intervention with the provision of dynamic imaging which is crucial for providing safe and effective patient management.