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Ultrasound Elastography applied sciences Ultrasound Elastography Edited by Christoph F. Dietrich Printed Edition of the Special Issue Published in Applied Sciences www.mdpi.com/journal/applsci Ultrasound Elastography Ultrasound Elastography Special Issue Editor Christoph F. Dietrich MDPI • Basel • Beijing • Wuhan • Barcelona • Belgrade Special Issue Editor Christoph F. Dietrich Caritas Krankenhaus Bad Mergentheim Germany Editorial Office MDPI St. Alban-Anlage 66 4052 Basel, Switzerland This is a reprint of articles from the Special Issue published online in the open access journal Applied Sciences (ISSN 2076-3417) from 2017 to 2018 (available at: https://www.mdpi.com/journal/ applsci/special issues/Ultrasound Elastography). For citation purposes, cite each article independently as indicated on the article page online and as indicated below: LastName, A.A.; LastName, B.B.; LastName, C.C. Article Title. Journal Name Year, Article Number, Page Range. ISBN 978-3-03897-910-4 (Pbk) ISBN 978-3-03897-911-1 (PDF) c 2019 by the authors. Articles in this book are Open Access and distributed under the Creative Commons Attribution (CC BY) license, which allows users to download, copy and build upon published articles, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact of our publications. The book as a whole is distributed by MDPI under the terms and conditions of the Creative Commons license CC BY-NC-ND. Contents About the Special Issue Editor ...................................... vii Christoph F. Dietrich and Jeffrey C. Bamber Editorial on the Special Issue of Applied Sciences on the Topic of Elastography Reprinted from: Applied Sciences 2018, 8, 1232, doi:10.3390/app8081232 ............... 1 Faisal N. Baig, Shirley Y. W. Liu, Hoi-Chun Lam, Shea-Ping Yip, Helen K. W. Law and Michael Ying Shear Wave Elastography Combining with Conventional Grey Scale Ultrasound Improves the Diagnostic Accuracy in Differentiating Benign and Malignant Thyroid Nodules Reprinted from: Applied Sciences 2017, 7, 1103, doi:10.3390/app7111103 ............... 8 Cheng-Han Lee, Yung-Liang Wan, Tse-Hwa Hsu, Shiu-Feng Huang, Ming-Chin Yu, Wei-Chen Lee, Po-Hsiang Tsui, Yi-Cheng Chen, Chun-Yen Lin and Dar-In Tai Interpretation US Elastography in Chronic Hepatitis B with or without Anti-HBV Therapy Reprinted from: Applied Sciences 2017, 7, 1164, doi:10.3390/app7111164 ............... 22 Mariusz Łucejko and Robert Flisiak Effect of HCV Core Antigen and RNA Clearance during Therapy with Direct Acting Antivirals on Hepatic Stiffness Measured with Shear Wave Elastography in Patients with Chronic Viral Hepatitis C Reprinted from: Applied Sciences 2018, 8, 198, doi:10.3390/app8020198 ................ 34 Xuejun Zhang, Xiangrong Zhou, Takeshi Hara and Hiroshi Fujita Non-Invasive Assessment of Hepatic Fibrosis by Elastic Measurement of Liver Using Magnetic Resonance Tagging Images Reprinted from: Applied Sciences 2018, 8, 437, doi:10.3390/app8030437 ................ 46 Sheng-Hung Chen and Cheng-Yuan Peng Ultrasound-Based Liver Stiffness Surveillance in Patients Treated for Chronic Hepatitis B or C Reprinted from: Applied Sciences 2018, 8, 626, doi:10.3390/app8040626 ................ 59 Kristen M. Meiburger, Massimo Salvi, Maurizio Giacchino, U. Rajendra Acharya, Marco A. Minetto, Cristina Caresio and Filippo Molinari Quantitative Analysis of Patellar Tendon Abnormality in Asymptomatic Professional “Pallapugno” Players: A Texture-Based Ultrasound Approach Reprinted from: Applied Sciences 2018, 8, 660, doi:10.3390/app8050660 ................ 69 Christoph F. Dietrich, Roxana Sirli, Giovanna Ferraioli, Alina Popescu, Ioan Sporea, Corina Pienar, Christian Kunze, Heike Taut, Simone Schrading, Simona Bota, Dagmar Schreiber-Dietrich and Dong Yi Current Knowledge in Ultrasound-Based Liver Elastography of Pediatric Patients Reprinted from: Applied Sciences 2018, 8, 944, doi:10.3390/app8060944 ................ 82 Siu Ngor Fu, Hsing-Kuo Wang and Chen Huang A Novel Method for Assessing Regional Tendon Stiffness and Its Significance Reprinted from: Applied Sciences 2018, 8, 1156, doi:10.3390/app8071156 ...............101 Catherine Payne, Peter Watt and Nick Webborn Shear Wave Elastography Measures of the Achilles Tendon: Influence of Time of Day, Leg Dominance and the Impact of an Acute 30-Minute Bout of Running Reprinted from: Applied Sciences 2018, 8, 1170, doi:10.3390/app8071170 ...............109 v Roald Flesland Havre, Jo Erling Riise Waage, Anesa Mulabecirovic, Odd Helge Gilja and Lars Birger Nesje Strain Ratio as a Quantification Tool in Strain Imaging Reprinted from: Applied Sciences 2018, 8, 1273, doi:10.3390/app8081273 ...............123 vi About the Special Issue Editor Christoph F. Dietrich, Prof. Dr., MBA, is Chief of Internal Medicine 2 at Caritas-Krankenhaus Bad Mergentheim, Germany. He has also studied philosophy and history. He specializes in internal medicine, gastroenterology, hepatology, proctology, pneumology, hematology, oncology, palliative care, and geriatric medicine. He was the President of EFSUMB from 2013 to 2015 and of DGE-BV in 2013, and he is currently the Vice President of WFUMB (2017–2019). vii applied sciences Editorial Editorial on the Special Issue of Applied Sciences on the Topic of Elastography Christoph F. Dietrich 1,2,* ID and Jeffrey C. Bamber 3 1 Sino-German Tongji-Caritas Research Center of Ultrasound in Medicine, Department of Medical Ultrasound, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China 2 Department of Internal Medicine 2, Medizinische Klinik 2, Caritas Krankenhaus Bad Mergentheim, Uhlandstraße 7, 97980 Bad Mergentheim, Germany 3 Joint Department of Physics and Cancer Research UK Imaging Centre, The Institute of Cancer Research and The Royal Marsden Hospital, Cotswold Road, Sutton, London SM2 5NG, UK; [email protected] * Correspondence: [email protected]; Tel.: +49-7931-58-2201; Fax: +49-7931-58-2290 Received: 20 June 2018; Accepted: 17 July 2018; Published: 26 July 2018 Keywords: guideline; EFSUMB; WFUMB; elastography; contrast enhanced ultrasound; point of care ultrasound; health care Elastography is the science of creating noninvasive images of the mechanical characteristics of tissues. The basic principles of elastography have been described some years ago and have remained unchanged since they were outlined in the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) guidelines [1,2]. The first elastography guidelines worldwide were introduced and published by EFSUMB in April 2013 [1,2], were updated in 2017 for the liver [3,4], and were followed by the Japanese Society of Ultrasound in Medicine (JSUM) [5] and the World Federation for Ultrasound in Medicine and Biology (WFUMB) guidelines on basic principles [6] and applications in various organs [7–14]. The mentioned guidelines provide an introduction to the physical principles and technology on which all forms of current commercially available ultrasound elastography are based. The practical advantages and disadvantages that are associated with each of the techniques are described, and guidance is provided on the optimisation of scanning technique, image display, image interpretation, and some of the known image artefacts. The EFSUMB and the WFUMB guideline articles can be freely downloaded from the EFSUMB website (www.efsumb.org)[15] and the WFUMB website (www.wfumb.org). As described in [1], ultrasound elastography uses ultrasonic echoes to observe tissue displacement as a function of time and space after applying a force that is either dynamic (e.g., by thumping or vibrating) or varying it so slowly that it is considered “quasi-static” (e.g., by probe palpation). The commercially available technologies can be classified according to whether this tissue displacement is (a) displayed directly as the imaged quantity, as in the method that is known as acoustic radiation force impulse (ARFI) imaging; (b) used to calculate and display strain, producing what is termed strain elastography (SE); or (c) used to calculate and display an image of shear wave speed. The last of these is an image that is, in principle, quantitative for a tissue property and is the only one that requires the creation of a shear wave, which in turn requires the use of a dynamic force. The others may use a dynamic force but can also work with a static or nearly static force [1]. However, even the measurement of shear wave speed is dependent on system parameters such as the applied shear force and the frequency of the shear wave. Elastography may be considered as a type of remote palpation that allows the measurement and display of biomechanical properties that are associated with the elastic restoring forces in the tissue that act against shear deformation. This view unifies the different types of elastography, namely SE, ARFI imaging, and SWE, and explains why they all display images with contrast for the same underlying information, which is associated with the shear elastic modulus. Appl. Sci. 2018, 8, 1232; doi:10.3390/app80812321 www.mdpi.com/journal/applsci Appl. Sci. 2018, 8, 1232 A variety of methods that measure shear wave speed should be grouped under the term shear wave elastography (SWE). These include systems that calculate either the regional values of shear wave speed (without making images) using methods referred to as transient elastography (TE, including vibration-controlled transient elastography, VCTE) and point shear-wave elastography (pSWE), or images of shear
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