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Background: Ultrasonography is the gold standard imaging method for scrotal investigation. Colour Doppler ultrasonography, contrast-enhanced ultrasonography and sonoelastography allow sonographers to assess size, echotexture, vascular features and stiffness of the scrotal organs and abnormalities. Scrotal ultrasonography has been used to investigate male reproductive health, scrotal pain, masses and trauma. However, ultrasonography thresholds/classifications used to distinguish normal and pathologic features of the scrotal organs have changed over time, and have not yet been fully standardized., Objectives: To evaluate historical trends for the standards in scrotal ultrasonography: what was, what is and what will be normal., Methods: An extensive Medline search was performed identifying the most relevant studies in the English language from inception to date., Results: We provide here (i) a brief overview of the history of ultrasonography, (ii) current indications for scrotal ultrasonography and (iii) previous and current normal values, cut-offs and classifications of the main colour-Doppler ultrasonography parameters/characteristics of the scrotal organs, as derived from recent guidelines and evidence-based studies. In addition, we report recommendations and the clinical utility of contrast-enhanced ultrasonography and sonoelastography. Finally, we discuss critical issues needing further evidence and future directions to fill in the current gaps., Discussion: Several studies on scrotal ultrasonography are available. However, guidelines/recommendations dealing with specific ultrasonography applications have been published only in recent years. More recently, the European Academy of Andrology published evidence-based scrotal colour-Doppler ultrasonography reference ranges/normative parameters derived from a cohort of healthy, fertile men. In addition, a standardization of the methodology to evaluate qualitative and quantitative colour-Doppler ultrasonography parameters was reported. Other international societies reported indications, methodological standards, clinical utility and limitations of contrast-enhanced ultrasonography and sonoelastography., Conclusions: To date, colour-Doppler ultrasonography normative values for the scrotal organs are available. However, a wide international consensus on assessment and classification of several ultrasonography parameters is still lacking. An alignment of the world societies on these issues is advocated., (© 2021 American Society of Andrology and European Academy of Andrology.)

Early detection of chronic kidney disease is important to prevent progression of irreversible kidney damage, reducing the need for renal transplantation. Shear wave elastography is ideal as a quantitative imaging modality to detect chronic kidney disease because of its non-invasive nature, low cost and portability, making it highly accessible. However, the complexity of the kidney architecture and its tissue properties give rise to various confounding factors that affect the reliability of shear wave elastography in detecting chronic kidney disease, thus limiting its application to clinical trials. The objective of this review is to highlight the confounding factors presented by the complex properties of the kidney, in addition to outlining potential mitigation strategies, along with the prospect of increasing the versatility and reliability of shear wave elastography in detecting chronic kidney disease., (Copyright © 2021 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.)

Ultrasound elastography is a modern imaging technique that has developed rapidly in recent years. It enables objective measurement of tissue stiffness, a physical property intuitive to the human sense of touch. This novel technology has become a hotspot and plays a major role in scientific research and academic practice. Presently, ultrasound elastography has been used in the identification of benign and malignant tumors in superficial organs, such as breast and thyroid, providing clinically accurate diagnosis and treatment. The method has also been widely used for the liver, kidney, prostate, lymph nodes, blood vessels, skin and muscle system. In the application of cervical lesions, ultrasound elastography can distinguish normal cervix from abnormal cervix and differentiate benign from malignant lesions. It can significantly improve the diagnostic specificity for cervical cancer and is also useful for assessing infiltration depth and stage of cervical cancer, as well as predicting chemoradiotherapy treatment response. For cervical evaluation during pregnancy, ultrasound elastography is useful for assessing cervical softening and predicting premature delivery and outcome of induced labor. This article reviews the principles of ultrasound elastography as well as the current status and limitations in its application for cervical lesions and the cervix during pregnancy., Competing Interests: Conflict of interest disclosure The authors declare no conflicts of interest., (Copyright © 2021 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.)

Neuroimaging techniques that can sensitivity characterize healthy brain aging and detect subtle neuropathologies have enormous potential to assist in the early detection of neurodegenerative conditions such as Alzheimer's disease. Magnetic resonance elastography (MRE) has recently emerged as a reliable, high-resolution, and especially sensitive technique that can noninvasively characterize tissue biomechanical properties (i.e., viscoelasticity) in vivo in the living human brain. Brain tissue viscoelasticity provides a unique biophysical signature of neuroanatomy that are representative of the composition and organization of the complex tissue microstructure. In this article, we detail how progress in brain MRE technology has provided unique insights into healthy brain aging, neurodegeneration, and structure-function relationships. We further discuss additional promising technical innovations that will enhance the specificity and sensitivity for brain MRE to reveal considerably more about brain aging as well as its potentially valuable role as an imaging biomarker of neurodegeneration. MRE sensitivity may be particularly useful for assessing the efficacy of rehabilitation strategies, assisting in differentiating between dementia subtypes, and in understanding the causal mechanisms of disease which may lead to eventual pharmacotherapeutic development., Competing Interests: Declaration of Competing Interest None., (Copyright © 2021. Published by Elsevier Inc.)

Recognizing that breast cancers present as firm, stiff lesions, the foundation of breast magnetic resonance elastography (MRE) is to combine tissue stiffness parameters with sensitive breast MR contrast-enhanced imaging. Breast MRE is a non-ionizing, cross-sectional MR imaging technique that provides for quantitative viscoelastic properties, including tissue stiffness, elasticity, and viscosity, of breast tissues. Currently, the technique continues to evolve as research surrounding the use of MRE in breast tissue is still developing. In the setting of a newly diagnosed cancer, associated desmoplasia, stiffening of the surrounding stroma, and necrosis are known to be prognostic factors that can add diagnostic information to patient treatment algorithms. In fact, mechanical properties of the tissue might also influence breast cancer risk. For these reasons, exploration of breast MRE has great clinical value. In this review, we will: (1) address the evolution of the various MRE techniques; (2) provide a brief overview of the current clinical studies in breast MRE with interspersed case examples; and (3) suggest directions for future research., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Sarcopenia is age-related progressive and generalized loss of skeletal muscle mass and strength. Its prevalence is rising, which poses a burden for society because it increases disability and dependency and therefore raises health care costs. Muscle mass quality, however-an essential part of sarcopenia-is not easily diagnosable yet. Recent interest has risen for ultrasonographic evaluation of muscle. This review introduces muscle elastography as a possible, easy and cheap tool to evaluate qualitative muscle parameters. Basic principles of muscle elastography are described, as well as different elastography techniques and some technical considerations. Furthermore, a proposal for practical guidelines is offered and factors influencing muscle stiffness are highlighted., (Copyright © 2020 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.)

Neuromuscular ultrasound is an accepted and valuable element in the evaluation of peripheral nerve and muscle disease. However, ultrasound has several limitations to consider, including operator dependency and lack of a viable contrast agent. Fortunately, new technological advances show promise in resolving these issues. Ultra-high resolution ultrasound enables imaging of the nerve at the fascicular level. Shear wave elastography imaging can provide measures of tissue stiffness that can act as a surrogate measure of nerve and muscle health. Photoacoustic imaging may overcome neuromuscular ultrasound's current lack of contrast agents to detect inflammation and other functional changes within nerve and muscle, while artificial intelligence stands to address operator dependency and improve diagnostic imaging. The basic principles of each of these technologies are discussed along with current research and potential future applications in neuromuscular imaging., (© 2020 Wiley Periodicals, Inc.)

Ultrasound elastography (USE) is becoming an important adjunct tool in the evaluation of various musculoskeletal (MSK) traumatic conditions and diseases, with an increasing number of applications and publications in recent years. This rapidly evolving technique enhances the conventional ultrasound (US) examination by providing information on the elastic properties of tissue alongside the morphological and vascular information obtained from B-mode US and Doppler imaging. Those performing USE must have basic knowledge of its proper imaging techniques and limitations. In this review article, we place the USE in historical perspective and discuss basic techniques and current applications of USE in the evaluation of various traumatic and pathologic conditions of fasciae, nerves, muscles, tendons, ligaments, and MSK soft tissue masses., Competing Interests: None declared., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

Background: Muscle weakness following critical illness is the consequence of loss of muscle mass and alteration of muscle quality. It is associated with long-term disability. Ultrasonography is a reliable tool to quantify muscle mass, but studies that evaluate muscle quality at the critically ill bedside are lacking. Shear wave ultrasound elastography (SWE) provides spatial representation of soft tissue stiffness and measures of muscle quality. The reliability and reproducibility of SWE in critically ill patients has never been evaluated., Methods: Two operators tested in healthy controls and in critically ill patients the intra- and inter-operator reliability of the SWE using transversal and longitudinal views of the diaphragm and limb muscles. Reliability was calculated using the intra-class correlation coefficient and a bootstrap sampling method assessed their consistency., Results: We collected 560 images. Longitudinal views of the diaphragm (ICC 0.83 [0.50-0.94]), the biceps brachii (ICC 0.88 [0.67-0.96]) and the rectus femoris (ICC 0.76 [0.34-0.91]) were the most reliable views in a training set of healthy controls. Intra-class correlation coefficient for inter-operator reproducibility and intra-operator reliability was above 0.9 for all muscles in a validation set of healthy controls. In critically ill patients, inter-operator reproducibility and intra-operator 1 and 2 reliability ICCs were respectively 0.92 [0.71-0.98], 0.93 [0.82-0.98] and 0.92 [0.81-0.98] for the diaphragm; 0.96 [0.86-0.99], 0.98 [0.94-0.99] and 0.99 [0.96-1] for the biceps brachii and 0.91 [0.51-0.98], 0.97 [0.93-0.99] and 0.99 [0.97-1] for the rectus femoris. The probability to reach intra-class correlation coefficient greater than 0.8 in a 10,000 bootstrap sampling for inter-operator reproducibility was respectively 81%, 84% and 78% for the diaphragm, the biceps brachii and the rectus femoris respectively., Conclusions: SWE is a reliable technique to evaluate limb muscles and the diaphragm in both healthy controls and in critically ill patients., Trial Registration: The study was registered (ClinicalTrial NCT03550222).

Ultrasound has become a useful tool in the workup of pediatric patients because of the highly convenient, cost-effective, and safe nature of the examination. With rapid advancements in anatomic and functional ultrasound techniques over the recent years, the diagnostic and interventional utility of ultrasound has risen tremendously. Advanced ultrasound techniques constitute a suite of new technologies that employ microbubbles to provide contrast and enhance flow visualization, elastography to measure tissue stiffness, ultrafast Doppler to deliver high spatiotemporal resolution of flow, three- and four-dimensional technique to generate accurate spatiotemporal representation of anatomy, and high-frequency imaging to delineate anatomic structures at a resolution down to 30 μm. Application of these techniques can enhance the diagnosis of organ injury, viable tumor, and vascular pathologies at bedside. This has significant clinical implications in pediatric patients who are not easy candidates for lengthy MRI or radiation-requiring examination, and are also in need of a highly sensitive bedside technique for therapeutic guidance. To best use the currently available, advanced ultrasound techniques for pediatric patients, it is necessary to understand the diagnostic utility of each technique. In this review, we will educate the readers of emerging ultrasound techniques and their respective clinical applications., Competing Interests: POTENTIAL CONFLICT OF INTEREST: The authors have indicated they have no potential conflicts of interest to disclose., (Copyright © 2019 by the American Academy of Pediatrics.)

The mechanical properties of soft tissues are closely associated with a variety of diseases. This motivates the development of elastography techniques in which tissue mechanical properties are quantitatively estimated through imaging. Magnetic resonance elastography (MRE) is a noninvasive phase-contrast MR technique wherein shear modulus of soft tissue can be spatially and temporally estimated. MRE has recently received significant attention due to its capability in noninvasively estimating tissue mechanical properties, which can offer considerable diagnostic potential. In this work, recent technology advances of MRE, its future clinical applications, and the related limitations will be discussed.

Background: The relationship between temporal progression of magnetic resonance elastography derived liver stiffness (MRE-LS) and progression of Fontan associated liver disease (FALD) is unknown. To assess this relationship, we hypothesized that progression of MRE-LS correlated with progression FALD severity and clinical outcomes., Methods: Retrospective review of Fontan patients who had >1 liver MRE, 2010-2016. Annual change in MRE-LS was the quotient of the difference between baseline and subsequent MRE-LS, and the interval between scans., Results: 22 patients were enrolled; median age 29(19-38) years, 14 (64%) males and 10 (46%) with atriopulmonary Fontan. Baseline and subsequent MRE-LS values were 5.4 ± 1.1 kPa and 5.8 ± 0.9 kPa" for clarity, interval between scans was 25 ± 5 months, and annual change in MRE-LS was 0.3 ± 0.2 kPa. Temporal change in MRE-LS correlated with temporal changes in model for end-stage liver disease (MELD) score (r = 0.84, p < 0.001) and model for end-stage liver disease excluding international normalized ratio (MELD-XI) score (r = 0.75, p = 0.001). The study cohort was divided into 2 groups using the mean annual change in MRE-LS as the cut point. Groups A and B comprised of patients with annual increase in MRE-LS ≥0.3 kPa (n = 6) and <0.3 kPa (n = 16) respectively. Composite adverse event endpoint (death, heart-liver transplant listing, palliative care, hospitalization, paracentesis) was more common in Group A (4 of 6, 67%) compared to Group B (3 of 16, 19%), p = 0.13 although this did not reach statistical significance due to small sample size., Conclusions: Progression of MRE-LS correlated with clinical deterioration as measured by worsening liver disease severity scores and the occurrence of adverse events., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Imaging plays an important role in the diagnosis and therapeutic response evaluation of muscular diseases. However, one important limitation is its incapacity to assess the in vivo biomechanical properties of the muscles. The emerging shear wave sonoelastography technique offers a quantifiable spatial representation of the viscoelastic characteristics of skeletal muscle. Elastography is a non-invasive tool used to analyze the physiologic and biomechanical properties of muscles in healthy and pathologic conditions. However, radiologists need to familiarize themselves with the muscular biomechanical concepts and technical challenges of shear wave elastography. This review introduces the basic principles of muscle shear wave elastography, analyzes the factors that can influence measurements and provides an overview of its potential clinical applications in the field of muscular diseases.

Chronic liver diseases often result in the development of liver fibrosis and ultimately, cirrhosis. Treatment strategies and prognosis differ greatly depending on the severity of liver fibrosis, thus liver fibrosis staging is clinically relevant. Traditionally, liver biopsy has been the method of choice for fibrosis evaluation. Because of liver biopsy limitations, noninvasive methods have become a key research interest in the field. Elastography enables the noninvasive measurement of tissue mechanical properties through observation of shear-wave propagation in the tissue of interest. Increasing fibrosis stage is associated with increased liver stiffness, providing a discriminatory feature that can be exploited by elastographic methods. Ultrasonographic (US) and magnetic resonance (MR) imaging elastographic methods are commercially available, each with their respective strengths and limitations. Here, the authors review the technical basis, acquisition techniques, and results and limitations of US- and MR-based elastography techniques. Diagnostic performance in the most common etiologies of chronic liver disease will be presented. Reliability, reproducibility, failure rate, and emerging advances will be discussed. © RSNA, 2018 Online supplemental material is available for this article.

About 92.1 million Americans suffer from at least one type of cardiovascular disease. Worldwide, cardiovascular diseases are the number one cause of death (about 31% of all global deaths). Recent technological advancements in cardiac ultrasound imaging are expected to aid in the clinical diagnosis of many cardiovascular diseases. This article provides an overview of such recent technological advancements, specifically focusing on tissue Doppler imaging, strain imaging, contrast echocardiography, 3D echocardiography, point-of-care echocardiography, 3D volumetric flow assessments, and elastography. With these advancements ultrasound imaging is rapidly changing the domain of cardiac imaging. The advantages offered by ultrasound imaging include real-time imaging, imaging at patient bed-side, cost-effectiveness and ionizing-radiation-free imaging. Along with these advantages, the steps taken towards standardization of ultrasound based quantitative markers, reviewed here, will play a major role in addressing the healthcare burden associated with cardiovascular diseases., (Copyright © 2017 Elsevier B.V. All rights reserved.)

In the last 10 years the availability of ultrasound elastography allowed to diagnose and stage liver fibrosis in a non-invasive way and changed the clinical practice of hepatology. Newer ultrasound-based techniques to evaluate properties of the liver tissue other than fibrosis are emerging and will lead to a more complete characterization of the full spectrum of diffuse and focal liver disease. Since these methods are currently undergoing validation and go beyond elastography for liver tissue evaluation, they were not included in the recent guidelines regarding elastography issued by the European Federation of Societies in Ultrasound in Medicine and Biology. In this review paper, we outline the major advances in the field of ultrasound for liver applications, with special emphasis on techniques that could soon be part of the future armamentarium of ultrasound specialists devoted to the assessment of liver disease. Specifically, we discuss current and future ultrasound assessment of steatosis, spleen stiffness for portal hypertension, and elastography for the evaluation of focal liver lesions; we also provide a short glimpse into the next generation of ultrasound diagnostic methods., (Copyright © 2017 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.)

Portal hypertension (PH) leads to serious complications, such as bleeding from gastroesophageal varices, ascites and portosystemic encephalopathy in patients with chronic liver disease (CLD). Gold standard methods for assessing PH and its complications include the measurement of hepatic venous pressure gradient and endoscopy; however, these are invasive, expensive and not available at all centres. Therefore, non-invasive alternatives have been the subject of extensive investigation over the last 20years. The present review focuses on the role of ultrasound elastography - a novel group of non-invasive techniques used to measure stiffness in target organs. In the context of CLD these methods are used to identify the presence of PH, its severity, and the risk of PH-related complications. The rationale, accumulated evidence, advantages and limitations of liver and spleen stiffness measurements evaluated by different ultrasound elastography techniques in patients with advanced CLD is discussed. Recent data regarding the use of ultrasound elastography techniques in patients with non-cirrhotic forms of PH are also described., (Copyright © 2017 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.)

Liver stiffness measurement (LSM) frequently overestimates the severity of liver fibrosis in nonalcoholic fatty liver disease (NAFLD). Controlled attenuation parameter (CAP) is a new parameter provided by the same machine used for LSM and associated with both steatosis and body mass index, the two factors mostly affecting LSM performance in NAFLD. We aimed to determine whether prediction of liver fibrosis by LSM in NAFLD patients is affected by CAP values. Patients (n = 324) were assessed by clinical and histological (Kleiner score) features. LSM and CAP were performed using the M probe. CAP values were grouped by tertiles (lower 132-298, middle 299-338, higher 339-400 dB/m). Among patients with F0-F2 fibrosis, mean LSM values, expressed in kilopascals, increased according to CAP tertiles (6.8 versus 8.6 versus 9.4, P = 0.001), and along this line the area under the curve of LSM for the diagnosis of F3-F4 fibrosis was progressively reduced from lower to middle and further to higher CAP tertiles (0.915, 0.848-0.982; 0.830, 0.753-0.908; 0.806, 0.723-0.890). As a consequence, in subjects with F0-F2 fibrosis, the rates of false-positive LSM results for F3-F4 fibrosis increased according to CAP tertiles (7.2% in lower versus 16.6% in middle versus 18.1% in higher). Consistent with this, a decisional flowchart for predicting fibrosis was suggested by combining both LSM and CAP values., Conclusions: In patients with NAFLD, CAP values should always be taken into account in order to avoid overestimations of liver fibrosis assessed by transient elastography. (Hepatology 2017;65:1145-1155)., (© 2016 by the American Association for the Study of Liver Diseases.)

Chronic liver disease has multiple causes, many of which are increasing in prevalence. The final common pathway of chronic liver disease is tissue destruction and attempted regeneration, a pathway that triggers fibrosis and eventual cirrhosis. Assessment of fibrosis is important not only for diagnosis but also for management, prognostic evaluation, and follow-up of patients with chronic liver disease. Although liver biopsy has traditionally been considered the reference standard for assessment of liver fibrosis, noninvasive techniques are the emerging focus in this field. Ultrasound-based elastography and magnetic resonance (MR) elastography are gaining popularity as the modalities of choice for quantifying hepatic fibrosis. These techniques have been proven superior to conventional cross-sectional imaging for evaluation of fibrosis, especially in the precirrhotic stages. Moreover, elastography has added utility in the follow-up of previously diagnosed fibrosis, the assessment of treatment response, evaluation for the presence of portal hypertension (spleen elastography), and evaluation of patients with unexplained portal hypertension. In this article, a brief overview is provided of chronic liver disease and the tools used for its diagnosis. Ultrasound-based elastography and MR elastography are explored in depth, including a brief glimpse into the evolution of elastography. Elastography is based on the principle of measuring tissue response to a known mechanical stimulus. Specific elastographic techniques used to exploit this principle include MR elastography and ultrasonography-based static or quasistatic strain imaging, one-dimensional transient elastography, point shear-wave elastography, and supersonic shear-wave elastography. The advantages, limitations, and pitfalls of each modality are emphasized. © RSNA, 2016.

Recent advances in the noninvasive imaging of chronic liver disease have led to improvements in diagnosis, particularly with magnetic resonance imaging (MRI). A comprehensive evaluation of the liver may be performed with the quantification of the degree of hepatic steatosis, liver iron concentration, and liver fibrosis. In addition, MRI of the liver may be used to identify complications of cirrhosis, including portal hypertension, ascites, and the development of hepatocellular carcinoma. In this review article, we discuss the state of the art techniques in liver MRI, namely, magnetic resonance elastography, hepatobiliary phase MRI, and liver fat and iron quantification MRI. The use of these advanced techniques in the management of chronic liver diseases, including nonalcoholic fatty liver disease, will be elaborated.

Background: There is a relationship between liver stiffness measurement (LSM) and outcome of HCV patients., Aim: To evaluate the performance of LSM to predict outcome of HCV patients at risk of liver-related complication., Methods: We established a retrospective longitudinal cohort of 341 HCV patients with unequivocal cirrhosis. All underwent LSM and were followed from September 2006 to July 2015. Outcome measure was a composite end-point of end-stage liver disease (ESLD) and/or hepatocellular carcinoma (HCC). Cox models and areas under receiver operating characteristic (AUROC) curves were used to evaluate independent risk factors of outcome., Results: Overall, LSM was below the 12.5 kPa threshold in 129 (37.8%) patients, including three-fourth and one-third of patients with or without a sustained virological response respectively. Liver disease progressed in 136 (39.9%) patients after a median observational period of 23.5 months. Older age, male gender, alcohol use disorders, metabolic syndrome and LSM were independent risk factors of liver disease progression. Age, alcohol use disorders and LSM were independently associated with ESLD. Age, gender and metabolic syndrome, but not LSM, were associated with HCC. The AUROC curves for disease progression, ESLD and HCC were 0.67, 0.70 and 0.58 respectively. Patients with a liver stiffness >12.5 kPa were at the highest risk of liver disease progression; below 12.5 kPa, liver stiffness was not discriminant., Conclusion: Liver stiffness measurement is not a surrogate of disease progression of HCV patients with cirrhosis. HCV patients with cirrhosis should undergo the recommended follow-up, regardless of liver stiffness measurement., (© 2016 John Wiley & Sons Ltd.)

Modern MR imaging protocols can yield both anatomic and functional information for the assessment of hepatobiliary and pancreatic malignancies. Diffusion-weighted imaging is fully integrated into state-of-the-art protocols for tumor detection, characterization, and therapy monitoring. Hepatobiliary contrast agents have gained ground in the evaluation of focal liver lesions during the last years. Perfusion MR imaging is expected to have a central role for monitoring therapy in body tumors treated with antivascular drugs. Approaches such as Magnetic resonance (MR) elastography and (1)H-MR spectroscopy are still confined to research centers, but with the potential to grow in a short time frame., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Comprehensive care that each general practitioner offers to his patients includes familiarity with different methods of diagnosis. In diagnosis today there are frequent indications of various liver scarring which first need to be diagnosed correctly and then treated and monitored over time. Chronic liver diseases are among the top ten causes of death in developed countries and one of the leading public health issues in the world. In Croatia, fibrosis and cirrhosis ranked 10th among causes of death in 2013, accounting for 1.95% of all deaths and even 3.11% in men. The degree of liver fibrosis is the most direct and the best way to indicate the seriousness of liver scarring, while prognosis depends on advancement of fibrosis. In this paper, we attempted to explain a noninvasive method called transient elastography (TE), its basic properties, advantages and disadvantages, diagnostic precision, as well as its application in medical practice. Currently, TE may be used as a diagnostic method for elimination of cirrhosis and may help determine severe fibrosis in patients with alcohol liver disease. By using two noninvasive diagnostic methods, it is possible to assess the stage of fibrosis (F ≥2) with high accuracy and avoid up to three-fourths of biopsy procedures. However, before including TE in the algorithm of diagnosis, it is necessary to define the standardized cut off values for different stages of liver scarring.

Background: Transient elastography (TE) is a safe and effective technology to noninvasively assess hepatic fibrosis in patients with numerous liver conditions. TE is not readily available to all Canadians, and data regarding how this technology is incorporated into clinical practice are lacking., Objective: To describe TE practices in Canada, and to identify strategies to optimize access and usage., Methods: All Canadian centres with TE devices were invited to complete a survey after obtaining purchasing data from the national distributor of the device. Descriptive statistics were generated., Results: Forty-two devices were available in Canada as of January 2015. Seventy-one percent are used in academic settings, 74% are hospital based and 26% are in private clinics. The test is performed by trained nurses in 48% of centres, physicians in 19%, technicians in 9.5% and by any member of the health care team in 19%. Nineteen percent of centres provide satellite clinics to perform the test. While the majority of the centres perform the test at no additional cost to patients, 29% charge a variable fee., Conclusion: In Canada, most TE devices are used in academic and⁄or hospital-based settings, thus limiting access to this technology to many patients. A sizeable minority of centres mandate patients pay variable out-of-pocket fees. Satellite clinics offered by some centres could increase access, but are not widespread. The lack of uniformity with TE practices in Canada suggests that a national policy is needed.

Objective: The purpose of the article is to review the diagnostic performance of ultra-sound and MR elastography techniques for detection and staging of liver fibrosis, the main current clinical applications of elastography in the abdomen., Conclusion: Technical and instrument-related factors and biologic and patient-related factors may constitute potential confounders of stiffness measurements for assessment of liver fibrosis. Future developments may expand the scope of elastography for monitoring liver fibrosis and predict complications of chronic liver disease.

Transsphenoidal surgery is the treatment of choice for acromegaly due to pituitary adenoma but it is not always possible to reduce or control tumor growth, inhibit GH hypersecretion and normalize IGF-I. The first-line drug treatment in 2013 remains the somatostatin analogues. In 2012 and 2013 have been published several publications presenting the prognosis of well-differentiated thyroid cancers of intermediate risk. Indeed, the dose of radioactive iodine administered to patients with "favorable" histology in this risk category should be reduced without change in prognosis. Elastograhy could, in combination with conventional ultrasound features, allow a better selection of thyroid nodules that need a cytology, with, however, still limitations in the detection of follicular carcinomas.

Traumatic brain injury (TBI) presents a variety of causes and symptoms, thus making the development of reliable diagnostic methods and therapeutic treatments challenging. Magnetic resonance elastography (MRE) is a technique that allows for a noninvasive assessment of the mechanical properties of soft biological tissue, such as tissue stiffness, storage modulus, and loss modulus. Importantly, by quantifying the changes in the stiffness of tissue that is often associated with disease, MRE is able to detect tissue pathologies at early stages. Recent improvements in instrumentation have allowed for the investigation of small samples with microscopic resolution (μMRE). We hypothesize that μMRE can sensitively detect variations in micromechanical properties in the brain caused by the compressive and shearing forces sustained during TBI. To test this hypothesis, we randomized 13 C57BL mice to receive a controlled cortical impact at a 0.5 mm or 0.75 mm depth, with both sham and naïve mice as controls. Our objective was to propagate mechanical shear waves throughout the brain for in vivo TBI μMRE imaging. The mechanical properties of the injured brain tissue were determined at days 0, 1, 7, and 28 post-injury. For both groups, we observed a significant drop in the stiffness of the impacted region immediately following the injury; the 0.75 mm animals experienced increased tissue softness that lasted longer than that for the 0.5 mm group. Although the shear stiffness, storage modulus, and loss modulus parameters all followed the same trend, the tissue stiffness yielded the most statistically significant results. Overall, this article introduces a transformative technique for mechanically mapping the brain and detecting brain diseases and injury.

Up until about two decades ago acoustic imaging and ultrasound imaging were synonymous. The term ultrasonography, or its abbreviated version sonography, meant an imaging modality based on the use of ultrasonic compressional bulk waves. Beginning in the 1990s, there started to emerge numerous acoustic imaging modalities based on the use of a different mode of acoustic wave: shear waves. Imaging with these waves was shown to provide very useful and very different information about the biological tissue being examined. We discuss the physical basis for the differences between these two basic modes of acoustic waves used in medical imaging and analyze the advantages associated with shear acoustic imaging. A comprehensive analysis of the range of acoustic wavelengths, velocities and frequencies that have been used in different imaging applications is presented. We discuss the potential for future shear wave imaging applications., (Copyright © 2013 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.)

Two-dimensional speckle tracking echocardiography (2D STE) is a novel technique of cardiac imaging for quantifying complex cardiac motion based on frame-to-frame tracking of ultrasonic speckles in gray scale 2D images. Two-dimensional STE is a relatively angle independent technology that can measure global and regional strain, strain rate, displacement, and velocity in longitudinal, radial, and circumferential directions. It can also quantify rotational movements such as rotation, twist, and torsion of the myocardium. Two-dimensional STE has been validated against hemodynamics, tissue Doppler, tagged magnetic resonance imaging, and sonomicrometry studies. Two-dimensional STE has been found clinically useful in the assessment of cardiac systolic and diastolic function as well as providing new insights in deciphering cardiac physiology and mechanics in cardiomyopathies, and identifying early subclinical changes in various pathologies. A large number of studies have evaluated the role of 2D STE in predicting response to cardiac resynchronization therapy in patients with severe heart failure. However, the clinical utility of 2D STE in the above mentioned conditions remains controversial because of conflicting reports from different studies. Emerging areas of application include prediction of rejection in heart transplant patients, early detection of cardiotoxicity in patients receiving chemotherapy for cancer, and effect of intracoronary injection of bone marrow stem cells on left ventricular function in patients with acute myocardial infarction. The emerging technique of three-dimensional STE may further extend its clinical usefulness., (© 2013, Wiley Periodicals, Inc.)

Liver Biopsy was considered the "gold standard" for severity assessment in chronic hepatitis for a very long time. In recent years, non invasive methods were developed in order to replace it. Among them ultrasound based elastographic methods: Transient Elastography (already validated and replacing liver biopsy in some countries), Real Time Tissue Elastography and Acoustic Radiation Force Impulse Elastography (currently under evaluation) and Shear Wave Elastography (the newest one). As an alternative to liver biopsy, the development of all these non invasive methods for dynamic evaluation of liver fibrosis will decrease the need for LB, making clinical care safer and more convenient for patients with liver diseases., (© Georg Thieme Verlag KG Stuttgart · New York.)

The technique of MR elastography (MRE) has emerged as a useful modality for quantitatively imaging the mechanical properties of soft tissues in vivo. Recently, MRE has been introduced as a clinical tool for evaluating chronic liver disease, but many other potential applications are being explored. These applications include measuring tissue changes associated with diseases of the liver, breast, brain, heart, and skeletal muscle including both focal lesions (e.g., hepatic, breast, and brain tumors) and diffuse diseases (e.g., fibrosis and multiple sclerosis). The purpose of this review article is to summarize some of the recent developments of MRE and to highlight some emerging applications., (Copyright © 2012 Wiley Periodicals, Inc.)

Speckle-tracking echocardiography (STE) is an advanced echocardiographic technique that allows a novel approach to the assessment of cardiac physiology through the study of myocardial mechanics. In its three-dimensional (3D) modality, it overcomes the drawbacks inherent to other echocardiographic techniques, namely two-dimensional echocardiography and tissue Doppler imaging. Several research studies and software improvements have led 3D-STE to become a promising tool for accurate evaluation of global and regional cardiac function. This article addresses the image acquisition, analytical methods, and parameters of myocardial mechanics that could be derived from 3D-STE. This systematic guidance may help to establish its usefulness in the global and regional evaluation of cardiac function, and to facilitate its clinical application., (© 2012, Wiley Periodicals, Inc.)

Speckle tracking is a new ultrasound tool to assess 2D ventricular global and segmental myocardial velocity and deformation (strain, strain rate). Multiple factors such as fetal motion, high heart rates, low blood pressure, small size of the heart, physiological cardiac translation, filling and maturational changes of myocardium, polyhydramnion, maternal obesity and aortic pulsation can degrade the image quality and result in artifacts and measurement errors which may have an impact on the final analysis. Therefore deformation indices such as strain and strain rate offer a quantitative technique for the estimation of global and segmental myocardial function and contractility. At present longitudinal peak systolic strain is the most commonly applied deformation parameter used to analyse segmental and global myocardial contractility in adults. When obtained using Doppler methods, these measurements are angle dependent, whereas speckle tracking techniques overcome the limitations of Doppler echocardiography which is a particular advantage in foetal echocardiography. Nevertheless, the time and training necessary to acquire high-quality video clips limit the implementation of speckle tracking into clinical routine. It is not yet clear whether this new technique will identify subclinical myocardial impairment earlier than with current techniques or allow for better discrimination between healthy fetuses and fetuses with congenital heart disease. The clinical use of speckle tracking will have to be demonstrated in larger groups of complicated pregnancies., (© Georg Thieme Verlag KG Stuttgart · New York.)

Biliary papillomatosis (BP) is a rare disorder of the biliary tract with a significant risk of malignant transformation and a high recurrence rate after operation due to the diffuse distribution of the disease. Preoperative diagnosis is difficult also by reason of the low sensitivity and specificity of conventional ultrasound (US), computed tomography (CT), magnetic resonance imaging (MRI), endoscopic retrograde cholangiography (ERC) and positron emission tomography (PET). Therefore, the introduction of new diagnostic imaging methods is of importance to improve the preoperative diagnosis of this originally as benign described disease which is reflected in the term of "benign papillomatosis of the biliary tree". The present review summarizes the literature and discusses new sonographic imaging techniques including contrast-enhanced ultrasound (CEUS), contrast-enhanced low mechanical endoscopic ultrasound (CELMI-EUS) and endoscopic ultrasound elastography., (© Georg Thieme Verlag KG Stuttgart · New York.)

The novel system of tactile analysis was used in the mechanoreceptor device. The local pressure measurement is carried out in in cameras, divided by the elastic membrane from the analyzed organ. The devise allows fast and adequate real-time measurement of tissue density and elasticity. The results, acquired with the use of the mechanoreceptor device were checked microscopically. The study showed high compatibility and adequacy of the novel mechanoreceptor.