The Experts below are selected from a list of 7839 Experts worldwide ranked by ideXlab platform
Nezam H. Afdhal - One of the best experts on this subject based on the ideXlab platform.
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the performance of vibration controlled Transient Elastography in a us cohort of patients with nonalcoholic fatty liver disease
The American Journal of Gastroenterology, 2016Co-Authors: Elliot B Tapper, Imad Nasser, Tracy Challies, Nezam H. AfdhalAbstract:The Performance of Vibration Controlled Transient Elastography in a US Cohort of Patients With Nonalcoholic Fatty Liver Disease
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cost effective evaluation of nonalcoholic fatty liver disease with nafld fibrosis score and vibration controlled Transient Elastography
The American Journal of Gastroenterology, 2015Co-Authors: Elliot B Tapper, Neil Sengupta, M Myriam G Hunink, Nezam H. AfdhalAbstract:Cost-Effective Evaluation of Nonalcoholic Fatty Liver Disease With NAFLD Fibrosis Score and Vibration Controlled Transient Elastography
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fibroscan vibration controlled Transient Elastography where does it stand in the united states practice
Clinical Gastroenterology and Hepatology, 2015Co-Authors: Elliot B Tapper, L Castera, Nezam H. AfdhalAbstract:With widespread screening and increasingly effective treatments for patients with viral hepatitis as well as the increasing prevalence of nonalcoholic fatty liver disease, the population presenting to the care of gastroenterologists and hepatologists is certain to increase. Assessment of advanced liver disease is traditionally invasive and expensive. Vibration-controlled Transient Elastography, commonly delivered by the FibroScan device, is an option recently approved by the Food and Drug Administration for the noninvasive assessment of liver disease at the point of care. Herein, we review the promise and pitfalls of vibration-controlled Transient Elastography with the aim of providing clinicians with a framework to interpret its results and apply this technology to the changing needs of our patients.
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Comparison of Transient Elastography, serum markers and clinical signs for the diagnosis of compensated cirrhosis
Journal of Gastroenterology and Hepatology, 2010Co-Authors: Raza Malik, Amama Sadiq, Rory Farnan, Shruti H. Mehta, Imad Nasser, Tracy Challies, Detlef Schuppan, Nezam H. AfdhalAbstract:Background and Aims: Non-invasive diagnosis of compensated cirrhosis is important. We therefore compared liver stiffness by Transient Elastography, APRI score, AST/ALT ratio, hyaluronic acid and clinical signs to determine which modality performed best at identifying compensated cirrhosis. Methods: Patients undergoing evaluation at a single center were recruited and had clinical, serological, endoscopy, radiological imaging, liver stiffness measurement and liver biopsy. Patients were stratified into cirrhotic and non-cirrhotic. Results: In 404 patients (124 cirrhosis), Transient Elastography was diagnostically superior to the other modalities yielding an AUC 0.9 ± 0.04 compared with hyaluronic acid (AUC 0.81 ± 0.04: P
Elliot B Tapper - One of the best experts on this subject based on the ideXlab platform.
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the performance of vibration controlled Transient Elastography in a us cohort of patients with nonalcoholic fatty liver disease
The American Journal of Gastroenterology, 2016Co-Authors: Elliot B Tapper, Imad Nasser, Tracy Challies, Nezam H. AfdhalAbstract:The Performance of Vibration Controlled Transient Elastography in a US Cohort of Patients With Nonalcoholic Fatty Liver Disease
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cost effective evaluation of nonalcoholic fatty liver disease with nafld fibrosis score and vibration controlled Transient Elastography
The American Journal of Gastroenterology, 2015Co-Authors: Elliot B Tapper, Neil Sengupta, M Myriam G Hunink, Nezam H. AfdhalAbstract:Cost-Effective Evaluation of Nonalcoholic Fatty Liver Disease With NAFLD Fibrosis Score and Vibration Controlled Transient Elastography
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fibroscan vibration controlled Transient Elastography where does it stand in the united states practice
Clinical Gastroenterology and Hepatology, 2015Co-Authors: Elliot B Tapper, L Castera, Nezam H. AfdhalAbstract:With widespread screening and increasingly effective treatments for patients with viral hepatitis as well as the increasing prevalence of nonalcoholic fatty liver disease, the population presenting to the care of gastroenterologists and hepatologists is certain to increase. Assessment of advanced liver disease is traditionally invasive and expensive. Vibration-controlled Transient Elastography, commonly delivered by the FibroScan device, is an option recently approved by the Food and Drug Administration for the noninvasive assessment of liver disease at the point of care. Herein, we review the promise and pitfalls of vibration-controlled Transient Elastography with the aim of providing clinicians with a framework to interpret its results and apply this technology to the changing needs of our patients.
Laurent Sandrin - One of the best experts on this subject based on the ideXlab platform.
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ACOUSTICS2008/1395 Transient Elastography in heterogeneous tissues
2020Co-Authors: Cécile Bastard, Jennifer Oudry, Yassine Mofid, Laurent SandrinAbstract:∞ (Echosens, Paris, France) is a Transient Elastography based device used to quantify liver fibrosis by following the propagation of a low frequency shear wave and measuring the mean Young’s modulus of the liver. This device has been successfully applied to homogeneous tissues such as liver in patients with chronic hepatitis C. Current developments in Transient Elastography are now headed toward the characterization of heterogeneous tissues. The estimation of the shear wave velocity can be achieved by solving the elastic wave equation taking into account either the 1D, the 2D or the 3D components of the displacement spatial derivatives. The objective of this study is to characterize focal nodules in human liver and to quantify heterogeneous fibrosis. We present the methods used to estimate the local shear wave velocity and the results of experiments conducted on heterogeneous phantoms and in the liver in vivo.
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Advances in liver stiffness measurements using Transient Elastography
2020Co-Authors: Laurent Sandrin, Véronique Miette, Céline FournierAbstract:Transient Elastography has been extensively val- idated for in vivo liver stiffness measurement (LSM) using Fibroscan R (Echosens, Paris, France). This non invasive and rapid procedure is used to assess liver fibrosis in adult patients. We present the recent advances in Transient Elastography for liver stiffness measurements in children and obese patients. Liver stiffness measurements were performed on children using a dedicated probe. Obese patients were measured with the standard probe. Patient position was changed and an ultrasound scanner was used to locate the measurement window in obese and morbid obese patients. Results show that liver stiffness measurements with Fibroscan R is feasible on children using the dedicated probe. Measurement success rate in obese patients is signifcantly im- proved using the left lateral decubitus position under ultrasound guidance. More patients would therefore benefit from this non invasive method to assess liver fibrosis and cirrhosis.
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Liver Stiffness Measurement Using Vibration-Controlled Transient Elastography
Liver Elastography, 2020Co-Authors: Laurent SandrinAbstract:Vibration-controlled Transient Elastography (VCTE™) (FibroScan®, Echosens™, Paris) pioneered the use of liver stiffness measurement for noninvasive fibrosis assessment in research and clinical practice worldwide. The history of the development of Transient Elastography, VCTE™ technology and FibroScan® device is detailed in this chapter. An explanation of the specific controls on which VCTE™ technology relies is provided along with a description of the operation of the FibroScan® device. The development of concomitant liver steatosis assessment using CAP™ is discussed. Recent findings such as the development of a dedicated exam for spleen stiffness measurement, surrogate marker of portal hypertension, and FibroScan®-based scores for enhanced fibrosis assessment and NASH are reported.
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Transient Elastography with the XL probe rapidly identifies patients with nonhepatic ascites.
Hepatic Medicine : Evidence and Research, 2012Co-Authors: A Kohlhaas, Laurent Sandrin, Cécile Bastard, E Durango, Gunda Millonig, Mohammad Golriz, Arianeb Mehrabi, Markus W. Büchler, Helmut K. Seitz, Sebastian MuellerAbstract:BACKGROUND: In contrast with other elastographic techniques, ascites is considered an exclusion criterion for assessment of fibrosis stage by Transient Elastography. However, a normal liver stiffness could rule out hepatic causes of ascites at an early stage. The aim of the present study was to determine whether liver stiffness can be generally determined by Transient Elastography through an ascites layer, to determine whether the ascites-mediated increase in intra-abdominal pressure affects liver stiffness, and to provide initial data from a pilot cohort of patients with various causes of ascites. METHODS AND RESULTS: Using the XL probe in an artificial ascites model, we demonstrated (copolymer phantoms surrounded by water) that a Transient Elastography-generated shear wave allows accurate determination of phantom stiffness up to a water lamella of 20 mm. We next showed in an animal ascites model that increased intra-abdominal pressure does not affect liver stiffness. Liver stiffness was then determined in 24 consecutive patients with ascites due to hepatic (n = 18) or nonhepatic (n = 6) causes. The cause of ascites was eventually clarified using routine clinical, imaging, laboratory, and other tools. Valid (75%) or acceptable (25%) liver stiffness data could be obtained in 23 patients (95.8%) with ascites up to an ascites lamella of 39 mm. The six patients (25%) with nonhepatic causes of ascites (eg, pancreatitis, peritoneal carcinomatosis) had a significantly lower liver stiffness ( 30 kPa). Mean liver stiffness was 5.4 kPa ± 1.3 versus 66.2 ± 13.3 kPa. CONCLUSION: In conclusion, the presence of ascites and increased intra-abdominal pressure does not alter underlying liver stiffness as determined by Transient Elastography. We suggest that, using the XL probe, Transient Elastography can be used first-line to identify patients with nonhepatic ascites at an early stage.
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Shear viscosity measurement using Vibration- Controlled Transient Elastography
2009 IEEE International Ultrasonics Symposium, 2009Co-Authors: Cécile Bastard, Jean-pierre Remenieras, Laurent SandrinAbstract:Vibration-Controlled Transient Elastography (VCTE™) has been successfully applied to quantify stiffness in the liver of human patients with chronic viral hepatitis C. However, this technique is based on the measurement of the shear wave group velocity and does not take advantage of the shear wave dispersion in the frequency domain, which is related to the viscosity of the medium. In this work, we propose two methods to measure shear viscosity using VCTE™. The first method is based on the measurement of the shear wave phase velocity at several frequencies. The second method relies on the decrease of the signal spectral centroid as a function of depth. These methods are first tested on simulated data obtained using a Green's function approach. Simulations are performed for shear wave velocities in the range of 1.0 to 4.5 m/s and shear viscosities in the range of 0.5 to 3.0 Pa.s. They show that using these techniques, it is possible to measure shear viscosity using VCTE™. Shear viscosity measurements are also performed in the liver in vivo. The mean shear viscosity obtained from 6 healthy volunteers is close to 1.8 Pa.s. Transient Elastography; elasticity; viscosity; dispersion, liver
Victor Manuel Montori - One of the best experts on this subject based on the ideXlab platform.
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ultrasound based Transient Elastography for the detection of hepatic fibrosis systematic review and meta analysis
Clinical Gastroenterology and Hepatology, 2007Co-Authors: Jayant A. Talwalkar, David M Kurtz, Scott J Schoenleber, Colin Patrick West, Victor Manuel MontoriAbstract:Background & Aims: Ultrasound-based Transient Elastography is a promising noninvasive alternative to liver biopsy for detecting hepatic fibrosis. However, its overall test performance in various settings remains unknown. The aims of this study were to perform a systematic review and meta-analysis of diagnostic accuracy studies comparing ultrasound-based Transient Elastography with liver biopsy for hepatic fibrosis. Methods: Electronic and manual bibliographic searches to identify potential studies were performed. Selection of studies was based on reported accuracy of ultrasound-based Transient Elastography compared with liver biopsy. Data extraction was performed independently by 2 reviewers. Meta-analysis combined the sensitivities, specificities, and likelihood ratios of individual studies. Extent and reasons for heterogeneity were assessed. Results: Nine studies in full publication were identified. For patients with stage IV fibrosis (cirrhosis), the pooled estimates for sensitivity were 87% (95% confidence interval [CI], 84%–90%), specificity 91% (95% CI, 89%–92%), positive likelihood ratio 11.7 (95% CI, 7.9–17.1), and negative likelihood ratio 0.14 (95% CI, 0.10–0.20). Among 7 investigations reporting patients with stages II–IV fibrosis, the pooled estimates for sensitivity were 70% (95% CI, 67%–73%), specificity 84% (95% CI, 80%–88%), positive likelihood ratio 4.2 (95% CI, 2.4–7.2), and negative likelihood ratio 0.31 (95% CI, 0.23–0.43). Diagnostic threshold (or cut-off value) bias was identified as an important cause of heterogeneity for pooled results in both patient groups. Conclusions: Ultrasound-based Transient Elastography appears to be a clinically useful test for detecting cirrhosis.
Masahiro Kikuchi - One of the best experts on this subject based on the ideXlab platform.
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evaluation of liver fibrosis by Transient Elastography using acoustic radiation force impulse comparison with fibroscan
Journal of Gastroenterology, 2011Co-Authors: Hirotoshi Ebinuma, Hidetsugu Saito, Mina Komuta, Keisuke Ojiro, Kanji Wakabayashi, Shingo Usui, Rumiko Umeda, Yuka Ishibashi, Tetsurou Takayama, Masahiro KikuchiAbstract:Background Accurate evaluation of liver fibrosis in patients with chronic liver damage is required to determine the appropriate treatment. Various approaches, including laboratory tests and Transient Elastography, have been used to evaluate liver fibrosis. Recently, Transient Elastography with acoustic radiation force impulse (ARFI) has been developed and applied with conventional ultrasonography. The aim of this study was to evaluate the clinical utility of Transient Elastography with ARFI and to compare the results with this method and those of the Fibroscan® procedure.
