Table Of ContentSERIES EDITOR James H. Thrall, MD
Radiologist-in-Chief
Massachusetts General Hospital
Juan M. Taveras Professor of Radiology
Harvard Medical School
Boston, Massachusetts
OTHER VOLUMES IN Breast Imaging
THE REQUISITES IN RADIOLOGY SERIES Cardiac Imaging
Genitourinary Radiology
Musculoskeletal Imaging
Neuroradiology
Nuclear Medicine
Ultrasound
Thoracic Radiology
Vascular & Interventional Radiology
1600 John F. Kennedy Blvd.
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PEDIATRIC RADIOLOGY: THE REQUISITES ISBN: 978-0-323-03125-7
Copyright © 2009, 1998 by Mosby, Inc., an affiliate of Elsevier Inc.
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Notice
Knowledge and best practice in this field are constantly changing. As new research and experience
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The Publisher
Library of Congress Cataloging-in-Publication Data
Blickman, Johan G.
Pediatric radiology : the requisites / Johan G. Blickman, Bruce R. Parker, Patrick D. Barnes. -- 3rd ed.
p. ; cm. -- (Requisites series)
Includes bibliographical references and index.
ISBN 978-0-323-03125-7
1. Pediatric radiology. I. Parker, Bruce R. II. Barnes, Patrick D. III. Title. IV. Series:
Requisites series.
[DNLM: 1. Diagnostic Imaging. 2. Child. 3. Infant. WN 240 B648p 2009]
RJ51.R3B55 2009
618.92’00757--dc22 2009007873
Acquisitions Editor: Rebecca Gaertner
Developmental Editor: Martha Limbach
Publishing Services Manager: Tina Rebane
Project Manager: Norm Stellander
Design Direction: Lou Forgione
Printed in The United States of America
Last digit is the print number: 9 8 7 6 5 4 3 2 1
To All My Children
JOHAN. G. (HANS) BLICKMAN
Contributors
Patrick D. Barnes, MD Rajesh Krishnamurthy, MD
Professor Clinical Professor of Radiology
Department of Radiology Baylor College of Medicine
Stanford University School of Medicine Staff Radiologist
Stanford, California Texas Children’s Hospital
Chief, Section of Pediatric Neuroradiology Houston, Texas
Director, Pediatric MRI and CT Center
Department of Radiology Bruce R. Parker, MD
Lucile Packard Children’s Hospital
Professor
Palo Alto, California
Departments of Radiology and Pediatrics
Baylor College of Medicine
Johan G. (Hans) Blickman, MD, PhD Chairman Emeritus
Professor and Chairman Department of Diagnostic Imaging
Department of Radiology Texas Children’s Hospital
Radboud University Medical Center Houston, Texas
Nijmegen, The Netherlands Professor (Emeritus) of Radiology and Pediatrics
Department of Radiology
Carla Boetes, MD, PhD Stanford University School of Medicine
Stanford, California
Professor of Radiology
Director of Mammography
Department of Radiology Geert Vanderschueren, MD, PhD
Maastricht University Medical Center Staff Radiologist
Maastricht, The Netherlands Department of Musculoskeletal Radiology
Leuven University Hospital
Lya Van Die, MD Leuven, Belgium
Assistant Professor of Radiology
Radboud University Medical Center
Nijmegen, The Netherlands
vii
Foreword
THE REQUISITES is a series of textbooks encompassing the One of the features of THE REQUISITES series most noted
fundamental building blocks of radiology practice. This series and appreciated in reader feedback is the use of tables and boxes
is approaching its third decade and continues to flourish due to to restate and summarize essential information in concise form.
the diligence and success of the authors in producing such high This reinforces the narrative discussion, and the liberal use of this
quality work. Pediatric Imaging: THE REQUISITES, authored by approach again highlights Pediatric Imaging: THE REQUISITES.
Dr. Hans Blickman and colleagues, again exemplifies this high THE REQUISITES have now become old friends to two or
standard. three generations of medical imagers. We have tried to remain
Pediatric imaging has evolved in many extremely impor- true to the original intent of the series, which was to provide the
tant ways since the publication of the first and second editions resident, fellow, or practicing physician with a text that might rea-
of Pediatric Imaging: THE REQUISITES. Among other trends, sonably be read within several days. In practice, we see residents
CT and MRI have taken on progressively important roles in the and fellows doing exactly that at the beginning of each subspe-
imaging of children, 3D imaging is playing a role, and ultrasound cialty rotation. The concise presentation and reasonable length
has continued to progress technologically. The increase in utiliza- of THE REQUISITES books allows them to be read and reread
tion of CT in children is the subject of public concern, and the several times during subsequent rotations and during preparation
need to keep radiation exposure as low as reasonably achievable for board examinations.
(ALARA) is highlighted by Dr. Blickman in his opening remarks. THE REQUISITES are not intended to be exhaustive but
Dr. Blickman has assembled a terrific team for the current edi- rather to provide basic conceptional, factual, and interpretative
tion, including Drs. Lya Van Die, Rajesh Krishnamurthy, Bruce material required for clinical practice. Each book is written by
Parker, Carla Boetas, Geert Vandershueren, and Patrick Barnes. nationally recognized authorities in the respective subspecialty
The addition of new authors reflects the expansion of knowledge areas. Each author is challenged to present material in the context
and the rising importance of subspecialization in pediatric imag- of today’s practice of radiology rather than grafting information
ing. In keeping with the philosophy of THE REQUISITES series, about new imaging methods onto old out-of-date material.
Dr. Blickman and his team are to be congratulated for capturing Dr. Blickman and his coauthors have done an outstanding job
the most important aspects of pediatric imaging and putting the in sustaining the philosophy of THE REQUISITES in this radi-
knowledge and information into an accessible and useful form. ology series. They have produced another truly contemporary
Some aspects of pediatric imaging are enduring. Certainly text for pediatric imaging. I believe that Pediatric Imaging: THE
knowledge of imaging anatomy and disease pathophysiology will REQUISITES will serve radiologists, pediatricians, and pediatric
never go out of style. However, the particular imaging methods of surgeons as a concise and useful introduction to the subject and
choice and the development of new protocols are very dynamic, will also serve as a very manageable text for review by fellows and
making it challenging to stay current. Dr. Blickman and his team practicing radiologists and cardiologists.
have done a great job capturing these changes.
Dr. Blickman has maintained the design of his book based James H. Thrall, MD
on an organ system approach, with each chapter introduced Radiologist-in-Chief
by a discussion of methods of importance to the respective or- Massachusetts General Hospital
gan system. This approach brings the discussion of technology Juan M. Taveras Professor of Radiology
and applications together in a very efficient way for the reader. Harvard Medical School
The illustrations have been widely updated, especially for Boston, Massachusetts
cross-sectional imaging.
viii
C 1
hapter
Pediatric Imaging
Johan G. (Hans) Blickman
On the one hand, the imaging of children is in many ways a As far as the radiologist’s being present: it is unavoidable,
microcosm of diagnostic imaging in general. Put another way, and rightly so. If we demand to be fully responsible medical
pediatric radiologists are the last of the general radiologists, those specialist doctors, we must be on the playing field with our col-
who are capable of using all modalities expertly. Although con- leagues “24/7.” The digital age has afforded us at the very least
ventional radiography and fluoroscopy are still the cornerstones the possibility to render our interpretations at any time of day or
of their practice, maybe even more so than in adult practice, the night, making the decision to be physically present ours.
cross-sectional imaging modalities such as ultrasonography (US), In the past 35 years, pediatric radiology has evolved so that it
computed tomography (CT), and magnetic resonance imaging fully merits its status as a subspecialty, pediatric imaging. Radio-
(MRI) do have their rightful place in the imaging armamentarium logists in training are tested in pediatric imaging at the end of
that is available today to imagers and clinicians who are caring for their 4 (or, in Europe, 5) years of training. Also, pediatric radio-
sick children. logy is one of the four subspecialties in 2005 for which the first
US clearly remains the favorite screening modality in children’s group of reexaminations were conducted for a time-limited certif-
imaging, more so in Europe than in the United States. This is icate of additional qualification (CAQ). The Society of Pediatric
probably a reflection of the many years that CT (and MRI) was Radiology is the oldest specialty organization within radiology; a
heavily regulated by European governmental agencies so that global pediatric imaging meeting is held every 5 years alterna-
more energy and resultant experience were given to US. It prob- tively in Europe and the United States, with full participation of
ably also reflects the greater reliance on contrast-enhanced and the Australasian Society of Pediatric Imaging.
post-processing US in renal and cardiac imaging in Europe, not in Teaching pediatric radiology presents some unique challenges.
the least because there is no European agency comparable to the It is not enough to rely on statements such as “A child is a small
U.S. Food and Drug Administration to temporize the introduc- adult” and “If it were your child, you would do every imaging
tion of newer contrast agents. modality as well.” But it is difficult to quantify what must be
Because reimbursement schemes in countries other than the known by a general radiologist about pediatric imaging. In addi-
United States are more favorable to “experimenting” with MRI, tion, retaining that knowledge is often a problem because chil-
this “non-ionizing” modality is also used more intensively and dren usually are only a small part of a general radiology practice.
routinely in urinary tract and cardiac imaging in those countries, Also, many general radiologists and technologists are not comfort-
as reflected in the origin of the relevant literature. able dealing with infants or young children.
With regard to CT, there is a real catch-up (or Americanization) In addition to their knowledge of general radiology, those
going on in Europe, led by the emergence of trauma centers as who image children must be fully conversant with anatomy,
well as the ever-growing demand for what we radiologists call embryology, and basic pediatrics. General radiologists should be
“non-focused imaging.” Everywhere there is a shortage of time familiar with these pediatric issues as well, although to a some-
and physicians, thus leading to an unfortunate increase in the use what lesser degree. Meticulous attention to indications for diag-
of CT as a “stethoscope.” nostic studies, standards of practice, and sensitivity to radiation
This is—of course, to older-generation imagers, regrettably— dosage are just as much a part of pediatric imaging as they are
a natural evolution. On the positive side, this movement is in other radiologic subspecialties. However, the pediatric radio-
also fueled by the move toward imaging time and resolution to logist is often more conscious of these issues. Indeed, the practice
near-pixel level, leading eventually to molecular and functional of imaging children demands special attention, knowledge, and
imaging. understanding.
None of these issues is unique to pediatric imaging. Especially This book, designed with the neophyte radiology resident in
in children, however, the radiation exposure aspect of imaging mind, attempts to answer the question what one could reasonably
tends to be attention grabbing. Although the practice of using read and retain during the usual 12- to 16-week rotation through
an ALARA (as low as reasonably achievable) radiation dose is pediatric radiology. The radiology resident must go from little or
widely accepted and followed, concern about radiation deaths no knowledge of pediatric radiology to a more or less working
is an issue everywhere. Vigilance about indications, proper (low knowledge in a short training interval. The radiologist in training
mAs) protocols, and the actual presence of pediatric imagers are must also understand pediatric disease processes and their diag-
required to guarantee optimal imaging of children. Fortunately, nosis, therapy, and follow-up. Finally, this knowledge must be
the rapidly expanding digitalization of our practice makes this retained in some form throughout one’s radiology career.
process easier. Consequently, the manner in which the clinical phases, from
The proper indication, use, and order of the different imaging initial diagnosis through therapy and follow-up, can be assessed
modalities are the legal responsibility of a properly trained and most efficiently by the different imaging modalities is the ulti-
practicing radiologist. American College of Radiology guidelines mate challenge of pediatric imaging and is the major focus of this
and cost reimbursement patterns are changing the way imaging is book. Therefore, it is hoped that this book will serve as a quick
being performed today, and we imagers must thus practice what reference for the more common vignettes that may have tempo-
we preach. rarily slipped the mind of a general radiologist who is interpreting
A powerful influence is the ever-present legal challenge in the imaging findings in a child.
United States, which is sadly making slight inroads in other parts Although pediatric radiology is a problem-oriented specialty, an
of the world as well. Protocols therefore must be as evidence- organ system approach is used in this book as a tool for presenting
based as possible, and the indications must be well managed if these essentials and as a method for systematic review. The re-
order management systems in electronic patient records of all- mainder of this book is divided into nine main chapters according
digital medical centers are to be optimally implemented. to organ system. Within each chapter, the imaging techniques as
