Prelims.qxd 9/13/04 3:20 PM Page i Obstetric Ultrasound Prelims.qxd 9/13/04 3:20 PM Page ii For Elsevier Senior Commissioning Editor: Sarena Wolfaard Project Development Manager: Dinah Thom Project Manager: Derek Robertson Designer: Judith Wright Illustrations: Hardlines Prelims.qxd 9/13/04 3:20 PM Page iii Obstetric Ultrasound How, Why and When THIRD EDITION Trish Chudleigh PhD DMU Superintendent Sonographer, Fetal Medicine Unit, St Thomas’ Hospital, London, UK Basky Thilaganathan MD MRCOG Director of Fetal Medicine, St George’s Hospital, London, UK E D I N B U R G H L O N D O N N E W YO R K O X F O R D P H I L A D E L P H I A S T L O U I S S Y D N E Y T O R O N T O 2004 Prelims.qxd 9/13/04 3:20 PM Page iv An imprint of Elsevier Science Limited © 2004, Elsevier Limited All rights reserved The right of Trish Chudleigh and Basky Thilaganathan to be identified as authors of this work has been asserted by them in accordance with the Copyright, Designs and Patents Act 1988 No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without either the prior permission of the publishers or a licence permitting restricted copying in the United Kingdom issued by the Copyright Licensing Agency, 90 Tottenham Court Road, London W1T 4LP Permissions may be sought directly from Elsevier’s Health Sciences Rights Department in Philadelphia, USA: phone: (+1) 215 238 7869, fax (+1) 215 238 2239, e-mail: healthpermissions@elsevier.com You may also complete your request on-line via the Elsevier homepage (http://www.elsevier.com), by selecting ‘Customer Support’ and then ‘Obtaining Permissions’ First edition 1986 Second edition 1992 Third edition 2004 ISBN 443 054711 British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library Library of Congress Cataloging in Publication Data A catalog record for this book is available from the Library of Congress Note Medical knowledge is constantly changing As new information becomes available, changes in treatment, procedures, equipment and the use of drugs become necessary The authors, contributors and publishers have taken care to ensure that the information given in this text is accurate and up to date However, readers are strongly advised to confirm that the information, especially with regard to drug usage, complies with the latest legislation and standards of practice The Publisher's policy is to use paper manufactured from sustainable forests Prelims.qxd 9/13/04 3:20 PM Page v v Acknowledgements We are grateful to the members of the Fetal Medicine Unit at St George’s Hospital for their support during the preparation of this text In particular we thank Gill Costello, Anisa Awadh, Sara Coates, Katy Cook, Heather Nash, Shanthi Sairam, Katherine Shirley-Price, Alison Smith and Alison Stock for their constructive criticism and help in providing the images Prelims.qxd 9/13/04 3:20 PM Page vi To Ben and Ella Prelims.qxd 9/13/04 3:20 PM Page vii vii Contents Contributors ix Preface xi Physics and instrumentation Preparing to scan 17 First trimester ultrasound 29 Problems of early pregnancy 51 Scanning the non-pregnant pelvis 63 Ultrasound and infertility 79 Routine second trimester screening – assessing gestational age 95 Routine second trimester screening – assessing fetal anatomy 113 The placenta and amniotic fluid 137 10 Craniospinal abnormalities 149 11 Other fetal abnormalities 161 12 Fetal growth 177 13 Discussing the findings 185 14 Invasive procedures 195 15 The physics of Doppler ultrasound and Doppler equipment 209 16 Evaluating the pregnancy using Doppler 223 Appendices 237 Index 255 Prelims.qxd 9/13/04 3:20 PM Page viii Prelims.qxd 9/13/04 3:20 PM Page ix ix Contributors Chapters and 15 Tony Evans BSc MSc PhD CEng Senior Lecturer in Medical Physics, Leeds General Infirmary, Leeds, UK Chapters and Dr Davor Jurkovic MD MRCOG Consultant Gynaecologist, Early Pregnancy and Gynaecology Assessment Unit, Kings College Hospital, London, UK Chapter Simon Kelly MB ChB FRANZCOG Lecturer, University of McGill, Montreal, Quebec, Canada App.qxd 9/11/04 9:52 PM Page 250 250 OBSTETRIC ULTRASOUND APPENDIX 11: MARKERS OF CHROMOSOMAL ABNORMALITY Marker Karyotype Agenesis of corpus callosum Cardiac abnormalities Choroid plexus cysts Clasped or overlapping fingers Clinodactyly Cystic hygroma Diaphragmatic hernia Dilated ureters Duodenal atresia Echogenic focus Echogenic bowel Holoprosencephaly Increased nuchal translucency Increased nuchal fold Severe IUGR Ventriculomegaly Lateral facial cleft Median facial cleft Multicystic renal dysplasia Non-immune hydrops Cystic hygroma Omphalocele Radial aplasia/thumb hypoplasia Rocker bottom feet Sandal gap Short femur or humerus Single umbilical artery Syndactyly/polydactyly trisomy 13 trisomy 13, 18, 21 trisomy 18 trisomy 18 trisomy 21 45 XO, trisomy 21, 18, 13 trisomy 18 trisomy 18, 21 trisomy 21 trisomy 21 trisomy 21 trisomy 13, 18 trisomy 21 trisomy 21 triploidy, trisomy 18 trisomy 21 trisomy 18 trisomy 13 trisomy 18 45 XO 45 XO trisomy 13, 18 trisomy 13 trisomy 18 trisomy 21 trisomy 21 trisomy 18, 21 trisomy 13 Probable risk of on of abnormal karyotypes listed in column 5% 15% low nk nk 90% 15% low 30% low low 90% 75% 30% 5% [...]... gynaecological and infertility investigations is encouraging specialization in particular areas of obstetric and gynaecological imaging In order to gain from the expertise of such specialists this edition incorporates chapters on the imaging and management of early pregnancy, gynaecology and infertility from international experts in these fields A clear understanding of the principles of ultrasound when applied... to the safe and effective use of ultrasound in clinical practice Understanding the principles of ultrasound, however, is frequently not synonymous with the skill of being able to impart that knowledge to others We hope that the reader of this edition will benefit from the clear thinking of, in our opinion, one of the best current teachers of the principles of 2D ultrasound and Doppler ultrasound The... Societies for Ultrasound in Medicine and Biology (EFSUMB), whose regular updates can be found in the European Journal of Ultrasound Power output when using Doppler is discussed in detail in Chapter 15 REFERENCES AND FURTHER READING Hedrick W R, Hykes D L, Starchman D E 1995 Ultrasound physics and instrumentation, 3rd edn Mosby Year Book Inc, St Louis, MO WFUMB 1989 Second World Federation of Ultrasound. .. other ceramic and can therefore be molded into almost any shape To establish an electrical 5 Ch01.qxd 9/11/04 9:53 PM Page 6 6 OBSTETRIC ULTRASOUND A B Figure 1.6 Images of a section showing incorrect (A) and correct (B) time gain compensation settings connection, thin layers of silver are evaporated onto the surface to form electrodes This creates a device that will expand and contract when a voltage... the growth, oscillation and decay of small gas bubbles under the influence of an ultrasound wave Small bubble nuclei are present in many tissues When subject to ultrasound these bubbles can be ‘pumped up’ Although their detailed behavior is complex, they often grow to some limiting size and continue to vibrate at the ultrasound frequency Laboratory studies have shown that cells and intact tissues can... in most ultrasound departments, the education and training of others has formed an integral part of what we do We hope that the combining of the technical expertise of the ultrasound practitioner with the clinical expertise of the obstetrician and our understanding of the challenges of working in a multidisciplinary environment make this text instructive to both the novice and the experienced ultrasound. .. MO WFUMB 1989 Second World Federation of Ultrasound in Medicine and Biology symposium on safety and standardization in medicinal ultrasound Ultrasound in Medicine and Biology 15: S1 15 Ch01.qxd 9/11/04 9:53 PM Page 16 Ch02.qxd 9/11/04 9:55 PM Page 17 17 Chapter 2 Preparing to scan CHAPTER CONTENTS The ultrasound equipment: components and their uses 17 The probe 18 The control panel 20 Measuring facilities... For further information of artifacts and their appearances the reader is referred to one of the standard ultrasound texts (Hedrick et al 1995) SAFETY The question of whether an ultrasound examination carries risks to the patient and/ or operator has been the subject of considerable research for many decades and is ongoing It remains true that noone has ever been shown to have been damaged as a result... the ultrasound wave by tissue All ultrasound tissue exposures produce heating The task is to identify where and if it is significant As absorption increases with increasing frequency, we would expect more heating from higher-frequency probes and, generally, this is true However, the temperature rise caused by an ultrasound beam is dependent on many factors, including: ● ● ● ● ● ● ● beam intensity and. .. influence on the quality of the ultrasound images THE PULSE ECHO PRINCIPLE The principle underlying the formation of ultrasound images is the same as that of underwater sonar (sound navigation and ranging) used by submarines and fishing boats It relies on the generation of a short burst of sound and the detection of echoes from reflectors in front of it The same principle applies when we hear our voices reflected ... Judith Wright Illustrations: Hardlines Prelims.qxd 9/13/04 3:20 PM Page iii Obstetric Ultrasound How, Why and When THIRD EDITION Trish Chudleigh PhD DMU Superintendent Sonographer, Fetal Medicine... understanding of the principles of ultrasound when applied to 2D imaging or to Doppler examinations is critical to the safe and effective use of ultrasound in clinical practice Understanding... Second World Federation of Ultrasound in Medicine and Biology symposium on safety and standardization in medicinal ultrasound Ultrasound in Medicine and Biology 15: S1 15 Ch01.qxd 9/11/04 9:53 PM