Modern Ultrasound Techniques Research Articles

Comments and illustrations of the European Federation of Societies for Ultrasound in Medicine contrast-enhanced ultrasound guidelines: Multiparametric imaging and EUS-guided sampling in rare pancreatic tumors. Benign mesenchymal pancreatic tumors.

The focus of the review is on primary benign mesenchymal pancreatic tumors and their imaging appearance. These tumors are extremely rare. Usually, they are not diagnosed until postoperative histology is available, and so even benign tumors have undergone extensive pancreatic resection. The very limited data on abdominal and EUS findings including contrast-enhanced techniques of these pancreatic lesions are summarized here. Case reports will be presented for some of these rare tumors with application of modern ultrasound and endosonographic techniques.

Histological analysis of the dermal and hypodermal layers of the face and correlation with high-frequency 24 MHz ultrasonography and elastosonography.

Knowledge of the structure of the face is of fundamental importance. In fact, the face is treated in many areas of medicine, from dermatology, to maxillofacial surgery, to otorhinolaryngology, to ophthalmology, etc. and anti-aging aesthetic treatments, and those for the resolution of blemishes are on the increase. For ethical reasons it is not possible to take biopsy samples for facial analysis in the aesthetic field. The main aim of this study was to demonstrate that a high-resolution bimodal ultrasound examination, combined with elastosonography, could be a valid tool for pre-treatment morphological evaluation. To achieve this goal, skin samples were taken from the forehead, zygomatic area, nasolabial fold, upper and lower lip from cadavers to histologically characterize their structure. Subsequently, these same areas were evaluated in vivo using conventional B-mode ultrasound with a 24 MHz high-frequency probe, and elastosonography. The data obtained with the different techniques were compared, in order to state that modern ultrasound techniques can provide similar histological information. The analysis showed that the superficial hypodermis presented a different shape and structure in the different areas, with the exception of the areas of the upper and lower lip, which appeared similar. With aging, the forehead and zygomatic area showed a volumetric increase in the superficial hypodermic layer, while the lip showed non-structural changes. The morphology of the nasolabial fold remained unchanged. When it is not possible to perform histological investigations on the face, to understand its characteristics and dynamics, ultrasound with a 24 MHz probe would seem to be the most suitable method, while elastosonography could be a valid method for evaluating the stiffness of the structural components.

Improved Spatiotemporal Resolution in Echocardiography Using Mixed Geometry Imaging Sequences.

Cardiac ultrasound seeks to image the most dynamic environment in the body-the moving heart. Many modern ultrasound imaging techniques address the tradeoff between spatial and temporal resolution using either narrow focused beams or with broad beam, synthetic aperture (SA) sequences that have been shown to suffer from motion artifacts. Retrospective encoding for conventional ultrasound sequences (REFoCUS) unifies the processing of these various geometric sequences, but the motion sensitivity of this approach has yet to be investigated. We hypothesize that a "mixed sequence" enabled by the REFoCUS method incorporating several beam geometries may better resolve cardiac motion over a wide field of view (FOV) and at a high frame rate. First, the motion sensitivity of REFoCUS was evaluated in simulation for several focused and broad transmit profiles. Focused transmissions resolve both lateral and axial motion much more effectively than broad transmissions, with performance similar to conventional beamforming techniques. Second, a mixed sequence was designed that insonifies the full field-of-view with plane wave (PW) transmissions and key moving targets with focused transmissions. This mixed sequence was tested in simulation and in vivo and was used to image the heart as well as the liver, a low-motion control. By combining a sparse PW sequence ( n=60 ) with a small group of targeted focused transmissions ( n = 10), the anterior mitral valve leaflet (AML) at its peak observed velocity was better resolved. We believe that mixed sequences have strong potential to resolve cardiac motion at clinically relevant frame rates.

Diagnosis of cardiac amyloidosis with the use of modern ultrasound techniques

Amyloidosis is a systemic disease caused by accumulation of insoluble amyloid proteins in the tissues. Cardiac amyloidosis (CA) lead to a severe heart failure, which is often therapy resistant. The severity of heart failure does not correspond to the degree of decrease in systolic function of the left ventricle, since diastolic function is more impairing. Early diagnosis of cardiac amyloidosis is important due to the presence of treatment regimens for this disease nowadays. The “gold standard” for cardiac amyloidosis diagnosis is myocardial biopsy, but non-invasive diagnostic methods are also of great importance. The aim of the article is a review of the ultrasound signs of cardiac amyloidosis, including the use of modern technologies, which helps to suspect CA to provide a further examination.

Integrity assessment of a crack inside a pressure vessel wall in RHPP “Bajina Bašta”

The goal of this research was to combine non-destructive test methods, specifically modern ultrasound testing techniques with numerical simulations via finite element method, to determine the risk of failure of a pressure vessel in the reversible hydropower plant “Bajina Bašta”. Using Phased Array Ultrasonic Technique and Time of Flight Diffraction technique, a crack with a length of 75 mm and depth of 20 mm was detected inside the pressure vessel wall, in the vertical welded joint. Based on the exact position and size of the crack, a numerical model was made in ABAQUS. Two models were made, with and without the crack, for comparison purposes. Since the obtained results did not show difference, it was decided to make another model, with different boundary conditions, providing a more realistic insight into the behaviour of the pressure vessel, which still remained in the safe zone.

Weakness of lower limb muscle in symptomatic peripheral artery disease with media sclerosis detected by ultrasound shear wave elastography.

Background: Symptomatic peripheral arterial disease (PAD) is difficult to non-invasively diagnose in the presence of calcified, media sclerotic arteries that are incompressible by blood pressure cuffs. Standard ankle-brachial index (ABI) measurements in these PAD patients are very often not helpful. Shear wave elastography (SWE) is a modern ultrasound technique to detect peripheral muscle stiffness changes i.e. muscle weakness during exercise. In a pilot study, we examined whether SWE could be a reproducible tool for diagnosing ischemic loss of muscle stiffness in patients with PAD and concomitant arterial media sclerosis. Patients and methods: N=13 consecutive patients with peripheral artery disease and media sclerosis were enrolled in the pilot study. All 13 patients were symptomatic in different stages of their PAD due to hemodynamically relevant arterial stenosis or occlusions of limb arteries as confirmed by oscillography, color-coded duplex sonography or angiography. Results: ABI measurements were invalid in all 13 patients. Mean SWE measurements of medial gastrocnemius muscles showed a significant transient muscle stiffness loss (weakness) at maximum exercise (active dorsal flexion of the foot, 103.4±25.9 kPa on the asymptomatic vs. 62.5±21.9 kPa on the symptomatic limb (p<0.001). Conclusions: SWE can reproducibly detect peripheral muscle weakness during exercise in the symptomatic leg of media sclerotic PAD patients. SWE of lower limb muscles may help to identify symptomatic PAD in patients presenting with invalid ABI measurements and unclear vascular status.

All about the Pancreas

All about the Pancreas Abstract. Ultrasound has made tremendous progress with the use of contrast media and elastography, particularly in patients with small, solid pancreatic lesions (SPL) <20mm and cystic tumors (CPL) of any size. In the case of solid and cystic pancreatic lesions, the differential diagnosis must first be evaluated after detection in order to define the indications for radical surgery, strategies for preserving the pancreatic parenchyma or simply for control examinations. Contrast-enhanced transcutaneous (TUS, CEUS) and endoscopic (EUS, CE-EUS) ultrasound and elastography facilitate further characterization of SPL and ZPL. Pancreatic ductal adenocarcinomas (PDAC) show hypoenhancement in contrast-enhanced ultrasound. The majority of the important differential diagnoses, on the other hand, are multi-enhancing. PDAC are almost always harder than healthy pancreatic parenchyma. In contrast, elastographically soft SPL are - with very few exceptions - benign. This review provides an overview of the use of modern ultrasound techniques to detect and characterize solid and cystic pancreatic lesions.

Regional Anesthesia in the Field for Trauma Victims.

This article addresses the importance of anesthesiologists providing regional anesthesia techniques that are beneficial to the care of trauma patients in the field. It also discusses the advantages and risks associated with regional anesthesia in the field along with how to avoid those risks. In addition, it describes some of the benefits of modern ultrasound techniques compared with landmark techniques with stimulation and other important considerations when performing regional anesthesia in the field. The article gives the unique indications, risks, and key points of the most useful regional techniques for anesthesiologists operating in field environments.

Risk stratification of sudden cardiac death in heart failure patients: is left ventricular ejection fraction alone sufficient?

According to current clinical guidelines, the risk of sudden cardiac death (SCD) in patients with heart failure is specified by left ventricular (LV) ejection fraction (EF). We believe that risk stratification and choice of patient management tactics should be based on modern diagnostic techniques aimed at identifying the anatomical and electrophysiological substrate of SCD. Therefore, LVEF alone is not enough to solve such problems. This review presents an analysis of current research on the novel predictors of SCD. The most promising areas include the identification of electrocardiological markers of fatal ventricular arrhythmias, modern ultrasound and magnetic resonance imaging techniques. The importance of electrophysiological tests in the verification of SCD risk is discussed. Based on the literature analysis, we can conclude that only a combination of different factors can significantly increase the diagnostic value of prognostic model and improve the primary prevention of SCD.

Early detection of pancreatic tumors by advanced EUS imaging.

The early detection of pancreatic ductal adenocarcinoma (PDAC) dramatically improves outcome. All available state-of-the-art imaging methods allow early detection with EUS being the best technique for exclusion of PDAC and detection of very early PDAC. Etiological differentiation of small SPL is important to guide individually tailored patients' management including radical surgery in resectable PDAC, medical (neoadjuvant or palliative intended) treatment in patients with non-resectable malignancy, pancreatic parenchyma saving strategies in some non-PDAC, and follow-up in particular in low-grade PanNEN or other small benign lesions. Multimodality EUS imaging including B-Mode assessment, elastography, contrast-enhancement and EUS-guided sampling is the most appropriate technique for diagnosis and risk assessment of small SPL. We present a review discussing modern (endoscopic) ultrasound imaging techniques including contrast enhanced ultrasound and elastography for the early detection and characterization of solid pancreatic lesions.

Anesthesiological considerations in emphysema surgery.

In the last decades, developing thoracic surgery raised the demands for sophisticated anesthesiological management. Especially patients with end-stage thoracic emphysema challenge the anesthesiologist to make modern surgery possible and to provide a safe and effective perioperative management. The development and scientific work-up of single lung ventilation (SLV) laid the cornerstone for surgery of the non-ventilated lung and hemi-thorax. However, modern medicine extended surgical options to extensive tracheal surgery and to patients suffering from severely insufficient lung-capacity precluding single-lung ventilation or artificial ventilation in se. For those critically ill, different techniques were thus developed and evaluated in recent research, among others, non-intubated surgery and surgery under extracorporeal perfusion support that temporarily avoids pulmonary gas exchange and ventilation via the trachea in any way. To tackle postoperative pain with its successive problems of immobilization, insufficient respiration and airway-clearance, regional anesthesia offers great advantages. Thoracic epidural anesthesia (TEA) is considered as the gold standard; complementary, modern ultrasound techniques make regional anesthesia possible even when contraindications prohibit neuraxial blocks. Especially paravertebral block, musculus serratus anterior block, intercostal block and the musculus erector spinae block provide good postoperative pain relief and appear to influence chronic post-thoracotmy pain positively. Careful preoperative preparation, intraoperative monitoring and patient-tailored, individual perioperative management by a well-trained team ensure good results, a good survival and favorable quality of life. This article provides a brief overview over state-of-the-art techniques and future perspectives to provide anesthesia in emphysema surgery.

Contrast-Enhanced Ultrasonography as a Novel Method for the Dynamic Visualization of Blood Flow and Fiber Blockage in Dialyzers: A Feasibility Study

The capillary dialyzer represents the central element of the extracorporeal blood circuit of a therapy system for hemodialysis. The aim of this study was to assess the blood-flow characteristics of dialyzers with the help of modern ultrasound techniques. Five brand-new dialyzers (FX80 classix, Fresenius Medical Care, Bad Homburg, Germany) and five dialyzers after a dialysis session were analyzed by different ultrasound techniques to detect functional and structural changes. B-mode and Doppler techniques were not suitable to describe differences in brand-new and clinically applied dialyzers. Contrast-enhanced ultrasonography, however, was able to visualize blood-flow profiles in the capillaries. Although dialyzers displayed no signs of clinical dysfunction, contrast-enhanced ultrasonography was able to detect blocked capillaries of varying degrees after a dialysis session in all five examined dialyzers. Consequently, the blood-flow velocity was higher in the remaining unblocked capillaries in comparison to the velocity in the brand-new dialyzers. This information may be helpful for improving the geometric design of dialyzers, including their capillary membranes, and optimizing anti-coagulation strategies in hemodialysis patients.

Updated DEGUM Quality Requirements for the Basic Prenatal Screening Ultrasound Examination (DEGUM Level I) between 18 + 0 and 21 + 6 weeks of gestation

A precondition for the early detection of fetal abnormalities is the high quality of prenatal basic ultrasound (screening examination). The objective of ultrasound screening is the recognition of abnormal fetal growth and fetal anatomical anomalies. The prenatal detection of fetal abnormalities enables detailed prenatal counselling of parents, improved care at birth and potentially a reduction in morbidity and mortality. In the guidelines for maternity care in Germany ("Mutterschaftsrichtlinien"), the performance of basic ultrasound in pregnancy is not clearly defined. The required image documentation includes a few biometric measurements only. Therefore, adherence to a standard technique and the possibility of audit are limited, thus not necessarily resulting in high screening quality. In this update of the DEGUM quality requirements for level I screening ultrasound examination between 18 + 0 and 21 + 6weeks of gestation, the required parameters, standard planes and required documentation are described in detail. The greater experience of gynecologists in the field of sonographic screening examinations and the use of a modern ultrasound technique allow improvement of the screening quality. This will improve the standard of basic ultrasound screening. Due to the enhanced standard of the DEGUM I examination, more pregnant women may benefit from a detailed ultrasound examination and specialized therapy in DEGUM level II and III centers. The required fetal structures are described in detail. This update of the requirements for level I DEGUM basic ultrasound examination between 18 + 0 and 21 + 6 weeks of gestation goes far beyond the guidelines for maternity care in Germany (the "Mutterschaftsrichtlinien") thereby elevating standards.

Modern ultrasound imaging of pancreatic tumors.

In patients with solid pancreatic lesions (SPLs), the differential diagnosis must be evaluated to determine whether radical surgery, pancreatic parenchyma-saving strategies, or follow-up is indicated. Contrast-enhanced (endoscopic) ultrasonography and elastography facilitate the further characterization of SPLs. The majority of cases of pancreatic ductal adenocarcinoma exhibit hypoenhancement with contrast-enhanced ultrasonography. Elastographically soft SPLs are benign with very few exceptions, whereas stiffer SPLs can be malignant or benign. This article reviews the current use of modern ultrasound imaging techniques, including contrast-enhanced ultrasonography and elastography, for the detection and characterization of SPLs. In particular, the unexcelled diagnostic potential of multiparametric endoscopic ultrasonography to detect and characterize small SPLs is highlighted.

STENOSIS OF THE CELIAC TRUNK – FROM DIAGNOSTICS TO TREATMENT

Compression stenosis of the celiac trunk (CSCT) is a syndrome based on the celiac trunk stenosis of varying degree, sometimes in combination with that of the superior mesenteric artery, caused by the compression of this vessel by the medial arched ligament of the diaphragm, as well as its internal legs and the neurofibrotic tissue of the celiac plexus. CSCT can cause chronic ischemia of the abdominal organs and chronic pain syndrome. The branches of the celiac trunk, supplying the stomach, liver, pancreas to the blood, are connected with the mesenteric arteries of the intestine in a common circle, therefore, with a lack of blood flow along one of the branches, the entire digestive tract suffers . The main clinical manifestation of CSCT is abdominal pain, observed in 97–100% patients. Angiography is the most invasive and, at the same time, the most informative method currently available to assess the extent and degree of the celiac trunk narrowing and to determine indications for surgical treatment. Ultrasound is a harmless, painless and at the same time informative diagnostic method for CSCT. A modern ultrasound technique is ultrasound with the use of echocontrast. Multi-detector CT angiography with multiplanar and 3D reconstruction is the optimal method of X-ray diagnostics of CSCT. MR angiography is successfully used both for preoperative preparation in patients with compression of the celiac trunk, and in the postoperative period. The methods of surgical treatment for abdominal ischemia are divided into palliative, decompressional and reconstructive. Modern diagnostic methods allow non-invasive methods to diagnose CSES in combination with clinical manifestations. The laparoscopic method is optimal for celiac trunk decompression, but the choice of the surgical treatment method should be considered individually.

Varicose veins of the small pelvis and pelvic congestion syndrome. A differentiated approach: the choice of method of contraception, treatment, prevention

The article considers the main points that affect the quality of life of women with varicose veins of small pelvis with congestion and without it, in particular the use of hormonal methods of contraception, and also discussed the issues of diagnostics, prevention and treatment of these diseases. Algorithms of clinical tactics for conducting such patients are presented. Particular attention is focused on the features of the appointment of hormonal drugs in this category of women. You can determine the methods of treatment and avoid long-term unreasonable prescription of various medicine (especially hormones that will mask or worsen the course of the disease) if you select groups of women with varicose veins of the small pelvis without congestion and with it (reflux).Varicose veins of the small pelvis and pelvic congestion syndrome are conditions that require an interdisciplinary and differentiated approach. Symptoms of these conditions can be put on a mask of various gynecological, urological, traumatological diseases. Anatomical and physiological features of the structure of the veins and the regulation of their venous tone explain the possibility of forming a venous congestive syndrome in women. This can be due to two reasons: due to the violation of the outflow of venous blood or due to the obstruction of any vein of the ovary, any increase in intravascular pressure not controlled by the venous tone at the level of the pelvis.Varicose veins of the small pelvis and pelvic congestion syndrome remain unexplored until the end. There are no uniform standards for their diagnostics. Varicose veins of the small pelvis and pelvic congestion syndrome are different diseases which requiring an understanding of the mechanisms of their development and consequences. If a pelvic varicose veins are suspected, the first diagnostic test is usually ultrasound. Modern ultrasound technique can evaluate blood flow in various veins. To study the blood flow in the veins, laparoscopy, venography in combination with CT or MRI can also be performed.

Tubal Disease and Impersonators/Masqueraders.

Ultrasound is considered the first-line imaging modality in the evaluation of the fallopian tubes. This chapter reviews both the physiologic and pathologic sonographic findings of the fallopian tubes and how to recognize characteristic entities. Specifically, it describes how to use ultrasound techniques to distinguish between pathologic processes including chronic versus acute pelvic inflammatory disease, as well as infertility, torsion, and malignancy. It also describes how to employ modern ultrasound techniques, such as color Doppler, three-dimensional imaging, and salpingocentesis in clinical practice.

Clinical application of modern ultrasound techniques after liver transplantation.

Liver transplantation has been established as a first-line therapy for a number of indications. Conventional ultrasound and contrast-enhanced ultrasound (CEUS) are methods of choice during the postoperative period as a safe and fast tool to detect potential complications and to enable early intervention if necessary. CEUS increases diagnostic quality and is an appropriate procedure for the examination of vessels and possibly bile ducts. This article presents the state of the art of ultrasound application during the early period after liver transplantation. It addresses common vascular complications and describes the identification of postoperative abnormal findings using ultrasound and CEUS.

The role of renal biopsy in small renal masses.

Renal biopsy is being increasingly proposed as a diagnostic tool to characterize small renal masses (SRM). Indeed, the wide adoption of imaging in the diagnostic workup of many diseases had led to a substantial increased incidence of SRM (diameter ≤4 cm). While modern ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI) techniques have high sensitivity for detecting SRM, none is able to accurately and reliably characterize them in terms of histological features. This is currently of key importance in guiding clinical decision-making in some situations, and in these cases renal biopsy should be considered. In this review, we aim to summarize the technique, diagnostic performance, and predicting factors of nondiagnostic biopsy, as well as the future perspectives.

Risk Factors and Perinatal Outcomes of Velamentous Umbilical Cord Insertion.

To explore the risk factors of velamentous umbilical cord insertion(VCI)and the impact of VCI on perinatal outcomes. The clinical data of 588 VCI patients who were treated in Beijing Gynecology and Obstetrics Hospital from January 2006 to January 2011 were retrospectively analyzed. In addition,61,143 non-VCI subjects were enrolled as the control group. The possible risk factors of VCI and the impact of VCI on perinatal outcomes were analyzed. In addition,the causes of perinatal deaths were analyzed. The gemellary pregnancy,multiple pregnancy,in vitro fitilization(IVF),placenta praevia,and placenta succenturiata/placenta bipartite were found to be the risk factors of VCI. The incidences of low birth weight,intrauterine growth restriction,asphyxia of newborns,deaths of fetuses or neonates,and single umbilical artery in the VCI group were significantly higher than those in the control group(all P<0.05). In 678 perineonates with VCI,the total death toll of perineonates was 7(1.0%),among whom the death causes included angiorrhexis of placenta praevia(n=1),preterm birth and low birth weight(n=3),torsion of cord(n=1),prolapse of cord(n=1),and placental abruption(n=1). The risk factors of VCI should be carefully monitored. A diagnosis of VCI,if any,should be correctly made by using modern ultrasound techniques before delivery,so as to lower the mortality of perineonates.