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Michael Riccabona Pediatric Ultrasound Requisites and Applications With contributions by Brian Coley Andreas Gamillscheg Bernd Heinzl Gerolf Schweintzger 123 Pediatric Ultrasound Michael Riccabona Pediatric Ultrasound Requisites and Applications With Contributions by Brian Coley, Andreas Gamillscheg, Bernd Heinzl, and Gerolf Schweintzger Michael Riccabona Division of Pediatric Radiology Department of Radiology University Hospital Graz Graz Austria First edition originally published by © Georg Thieme Verlag, 2000 ISBN 978-3-642-39155-2 ISBN 978-3-642-39156-9 DOI 10.1007/978-3-642-39156-9 Springer Heidelberg New York Dordrecht London (eBook) Library of Congress Control Number: 2014931858 © Springer Berlin Heidelberg 2014 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. Exempted from this legal reservation are brief excerpts in connection with reviews or scholarly analysis or material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Duplication of this publication or parts thereof is permitted only under the provisions of the Copyright Law of the Publisher's location, in its current version, and permission for use must always be obtained from Springer. Permissions for use may be obtained through RightsLink at the Copyright Clearance Center. Violations are liable to prosecution under the respective Copyright Law. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. While the advice and information in this book are believed to be true and accurate at the date of publication, neither the authors nor the editors nor the publisher can accept any legal responsibility for any errors or omissions that may be made. The publisher makes no warranty, express or implied, with respect to the material contained herein. Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com) Preface Ultrasound (US) has become the mainstay of paediatric radiology, particularly as neonates, infants and children offer ideal scanning conditions. Furthermore, with growing concern about radiation risks imposed to children for medical imaging, it has become even more important to exploit all options US may offer. Numerous papers have been written on this topic focusing on the child’s increased radiation sensitivity. Many campaigns have been initiated to promote radiation protection awareness throughout the world, such as the Image Gently campaign in the United States. However, children will continue to need medical imaging, and when trying to avoid irradiating methods such as CT and fluoroscopy, alternative non-invasive imaging must be available. Ultrasound is a relatively inexpensive, non-invasive and non-radiating imaging modality that promises to comply with all this requirements and must be promoted as the major initial modality. As a consequence of this paradigm, high standard paediatric US must become available to all children in need throughout the world, 24 h a day, 7 days a week, throughout the year. When trying to support and educate people to properly perform high level paediatric US I was often asked by participants of various courses and lectures, if I know a reasonably priced comprehensive booklet that covers all main aspects of paediatric US. It shouldn’t be too big, and should address not only all relevant aspects and diseases but also modern methods and must offer image examples. This request came particularly from colleagues from less wealthy countries such as the Third World and Asia, but also from sonographers and technicians, students, young colleagues and residents in training, as well as paediatricians, paediatric surgeons, and radiologists who are not full time paediatric radiologists. So I set out to try and create such booklet. In order to achieve these goals the text had to be short - thus this book is written in a checklist like style. The text is less extensive, and the legends are compact. Some less important conditions and aspects are only briefly mentioned or omitted, and image examples are focused on either very common important entities or on rare but still essential conditions that should not be overlooked or mistaken (i.e., relevant for differential diagnosis). Particular emphasis has been given to new approaches that widen US potential such as perineal US, contrast-enhanced US or filling techniques, using modern equipment and routinely encompassing Doppler sonography. However, basic features and rules also remain valid and important, particularly as they need to be respected and be addressed with any standard equipment; the description of those should enable the v vi Preface reader to make an US diagnosis provided careful and proper selection of adequate transducers and correct device settings is available. Further and more detailed information must, however, be retrieved from respective established textbooks. This project could only be realized by the help and support of Springer company, my colleagues at work, the input (and images) from my co-authors, and the patience of my partner Barbara. And the enterprise was further spurred by the motivation and inspiration I got from all the children and parents I encountered during daily work, their needs and suffering, but also their gratitude or their rewarding smile. I can only hope that you will find this booklet helpful for your daily needs and that it will achieve its goal, to contribute and improve access to dedicated paediatric US for all children in need, inspiring sonographers and physicians to outmost exploit US potential, to use creative approaches and apply US whenever there is an option that this might offer a diagnostic or therapeutic solution to the child’s condition. Even if US is financially not as rewarding as other imaging methods, it will hopefully be rewarding in terms of diagnostic success at reduced invasiveness and without radiation burden - an aspect I particularly learned to pursue and value from my four children to whom I want to dedicate this work. Graz, Austria January 2013 Prof. Michael Riccabona Acknowledgements I thank my co-authors for also providing many images for the various chapters of the book, and I am furthermore particular thankful to Prof. Coley for all the hard work he must have had with English editing, as well as Mrs. Einspieler for typing the scripts. vii Contents 1 Theory and Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1 Ultrasound (US) Physics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1.1 US Waves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1.2 Propagation and Modulation of US . . . . . . . . . . . . . . . . . . 1.2 Practical Application in US Device . . . . . . . . . . . . . . . . . . . . . . . . 1.2.1 Emission, Transmission, Reception and Amplification . . . 1.2.2 Signal Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2.3 Components of US Device . . . . . . . . . . . . . . . . . . . . . . . . . 1.3 US Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3.1 A (Amplitude)-Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3.2 (T)M-Mode (Time-Motion-Mode) . . . . . . . . . . . . . . . . . . . 1.3.3 B (Brightness)-Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3.4 Doppler Sonography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4 Artefacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4.1 General Remarks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4.2 Common Artefacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.5 Biologic Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.5.1 General Remarks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.5.2 Thermal Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.5.3 Mechanical Effects and Resonance . . . . . . . . . . . . . . . . . . 1.5.4 Potential Risks of Diagnostic US . . . . . . . . . . . . . . . . . . . . 1.5.5 Various Methods and Indices That Allow Estimation of Biological Risks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.6 How to Perform Paediatric US . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.6.1 Requisites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.6.2 Positioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.6.3 Device Handling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.6.4 Transducer Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.6.5 Course of Investigation and Measurements . . . . . . . . . . . . 1.7 Documentation and Interpretation . . . . . . . . . . . . . . . . . . . . . . . . . 1.7.1 Image Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.7.2 Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 2 2 4 4 5 6 9 9 9 10 11 11 11 12 15 15 16 16 17 18 19 19 20 21 22 23 25 25 26 ix