Emergency Radiology (Case Review)

409 Pages·2009·39.419 MB·English

by  Stuart E. Mirvis MD FACR, Kathirkamanathan Shanmuganathan MD, Lisa A. Miller MD, Clint W. Sliker MD

Stuart E. Mirvis, MD, FACR
Professor of Diagnostic Radiology and Nuclear Medicine
University of Maryland School of Medicine
Associate Vice Chairman for Medical Affairs
Director, Trauma/Emergency Radiology
University of Maryland Medical Center
Baltimore, Maryland
Kathirkamanathan Shanmuganathan, MD
Professor of Diagnostic Radiology and Nuclear Medicine
University of Maryland School of Medicine
University of Maryland Medical Center
Baltimore, Maryland
Lisa A. Miller, MD
Assistant Professor of Diagnostic Radiology and
Nuclear Medicine
University of Maryland School of Medicine
University of Maryland Medical Center
Baltimore, Maryland
Clint W. Sliker, MD
Assistant Professor of Diagnostic Radiology and
Nuclear Medicine
University of Maryland School of Medicine
University of Maryland Medical Center
Baltimore, Maryland
C A S E R E V I E W
Emergency Radiology
C A S E R E V I E W S E R I E S
1600JohnF.Kennedy Boulevard
Suite 1800
Philadelphia, PA 19103-2899
EMERGENCY RADIOLOGY: CASE REVIEW ISBN:978-0-323-04957-3
Copyright !2009, by Mosby, Inc.,anaffiliate of Elsevier Inc.
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NOTICE
Knowledge andbest practice in this fieldareconstantly changing. Asnewresearch and
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tionprovided(i)onproceduresfeaturedor(ii)bythemanufacturerofeachproducttobe
administered, to verifythe recommended doseor formula,the methodandduration of
administration, andcontraindications. It is the responsibility ofthe practitioner, relying on
thier ownexperienceandknowledge of thepatient, to makediagnoses,to determine
dosagesandthebesttreatmentforeachindividualpatient,andtotakeallappropriatesafety
precautions. Tothefullestextentofthelaw,neitherthePublishernortheAuthorsassume
anyliabilityforanyinjuryand/ordamagetopersonsorpropertyarisingoutorrelatedtoany
use ofthe material containedin this book.
The Publisher
Library of CongressCataloging-in-Publication Data
Emergency radiology/Stuart E. Mirvis... [etal.].– 1sted.
p. ;cm.– (Casereviewseries)
Includesbibliographical references.
ISBN978-0-323-04957-3
1.Diagnosis, Radioscopic--Case studies. 2.Radiography,
Medical–Case studies.3. Emergency medicine–Casestudies. 4.Medical
emergencies–Imaging–Case studies. I.Mirvis, Stuart E. II.Series.
[DNLM:1. Emergencies–Case Reports. 2.Radiography–methods–Case
Reports. 3. CriticalCare–methods–Case Reports. 4. Emergency Medical
Services–methods–Case Reports. 5.Woundsand
Injuries–radiography–Case Reports. WN200E532 2010]
RC78.E5827 2010
616.07057–dc22
2008032281
Acquisitions Editor: RebeccaS.Gaertner
Project Manager: BryanHayward
Design Direction: Steven Stave
Marketing Manager: Nancy Ciliberti
Printed in the UnitedStates ofAmerica.
Last digit is the printnumber: 9 8 7 6 5 4 3 2 1
To my wife, Linda R. Mirvis, for her love and tireless help.
—Stuart E. Mirvis
To my sister, Nalayini Shan, who is always available for moral support and
advice when required.
—Kathirkamanathan Shanmuganathan
To my mother, Vivian A. Miller, for her love and support.
—Lisa A. Miller
To my wife, Lisa, and my children, Lauren, Kelly, and Christopher, thank
you for the love, patience, and caring that motivate me to work hard
every day.
—Clint W. Sliker
ToourChairman,ReubenMezrich,MD,PhD,forsupportingthegrowthof
our section.
—Stuart E. Mirvis, Kathirkamanathan Shanmuganathan, Lisa A. Miller, and
Clint W. Sliker
SERIES FOREWORD
One of the most recent recognized subspecialties of radiology is Emergency
Radiology. While some opine that this should not be recognized as a separate
entity itself, delving into many already established subspecialties of radiology,
I disagree. Those who practice Emergency Radiology have to be so much better
versed in issues related to trauma, acute stroke care, acute abdomens, painful acute
pelvic conditions, and cardiopulmonary emergencies. The development of telera-
diology nighthawk services and 24/7 radiology makes mastery of this arena of radi-
ology a necessity. This is a niche job opportunity that requires special training and
knowledge.
In Baltimore, the University of Maryland Shock Trauma Center is the primary
referral locale for patients in serious motor vehicle accidents and/or catastrophes.
The Center has a stellar reputation in part because of the quality of the imaging
and the serviceprovided by the radiology group led by Stuart Mirvis. The material at
Dr. Mirvis’s disposal is outstanding in terms of quantity and quality. When I was
askedtosuggestanauthorforthisCaseReviewSeries,therewasonlyonecandidate
I wanted to enlist ... Stuart Mirvis. He and his team have created a wonderful new
firsteditiontotheseriesthatwillbevaluableworldwideevenassomeofthepractice
of emergency radiology becomes a global endeavor.
As the reader undoubtedly knows by now, this series is set up such that there are
gradations of difficulty so that the reader can assess his or her proficiency and can
use this self-evaluation to guide continued education. By referencing THE
REQUISITES textbook, the reader can ‘‘bone up’’ on a topic if a weakness is per-
ceived. Since each case in the book is distinct, this is the kind of text that you can
pick up and review at any time in your day, in your career.
Drs. Mirvis, Shanmuganathan, Miller, and Sliker have written a fantastic book that
I recommend for all radiologists reviewing ED studies. I welcome ‘‘Emergency
Radiology’’ to the Case Review Series. Don’t leave home without it!
David M. Yousem, MD, MBA
ix
PREFACE
In the past two decades, Emergency Radiology has emerged as a specialty that
continues to grow in importance. An ever-increasing number of our patients
enters the hospital via the emergency department (ED), usually not during routine
working hours. The need to provide quality radiology interpretation for these
patients, whenever they arrive, is, in part, responsible for the development of this
specialty. The recognition that Emergency Radiology encompasses a special and
well-defined body of clinical and imaging knowledge has fostered development of
the specialty, as well.
Regardlessoftheirareasofspecialization,mostpracticingandtrainingradiologists
will, at some time, provide emergency radiology coverage. The ED is a place where
diagnostic decisions must often be made rapidly and where the workload fluctuates
in an unpredictable manner. Familiarity with the common and some less common
diagnoses is necessary both to move patients efficiently through the typically very
busy ED and, more important, to promote rapid, appropriate treatment of acute
illness.
This case review book is meant to provide an opportunity to rapidly familiarize
the reader with the classic appearance of a range of emergent imaging pathology
and key points concerning these diagnoses. The Trauma and Emergency Radiology
section of the University of Maryland provides 24/7 coverage for both a busy urban
ED and a major level 1 trauma center. These venues provide us with plenty of ‘‘raw
material’’ from which to select our cases. In preparing these cases, we sought to be
comprehensive with the topics covered while providing a range of difficulties for
case interpretation. Hopefully, we have accomplished these goals.
Obviously, we are big fans of Emergency Radiology and enjoy the opportunity to
share our material with the radiology community at large; we hope you benefit from
itsreview.Aswepreparedthesecases,weheightenedourawarenessoflessfamiliar
entities and refreshed our knowledge of those more familiar to us. In so doing, we
and, by extension, our patients benefited. If review of these cases fosters in you a
sense of why we enjoy Emergency Radiology and helps you provide better care to
your ED patients, we certainly have succeeded in our efforts.
Stuart Mirvis, MD, FACR
K. Shanmuganathan, MD
Lisa Miller, MD
Clint Sliker, MD
xi
Opening Round
C AS E 1
1. What is the radiographic abnormality, and where is it located?
2. Is this the most sensitive radiographic projection for identifying this radiographic abnormality?
If not, what projection is?
3. What is the most common cause of this abnormality?
4. Is surgery always necessary to treat patients who manifest this abnormality?
3
A N S W E R S
C A S E 1
Pneumoperitoneum position for 10 to 20 minutes prior to image acquisition
1. Pneumoperitoneum located in both subphrenic inordertoallowgastomigratetonondependentpositions
spaces. intheperitoneum.However,thetimeconstraintsinherent
a busy emergency department, coupled with difficulties
2. Erect chest radiograph.
positioning and maintaining acutely ill patients into the
3. Recent surgery. necessarypositions,canreducetheabilityofradiography
to detect such small volumes of pneumoperitoneum. In
4. No.
difficult cases in which clinical suspicion for perforated
viscus is high but there are no peritoneal signs or other
References
clearindicationsforimmediatesurgicalexploration,com-
Cho KC, Baker SR: Extraluminal air. Diagnosis and sig- putedtomography(CT)maybeausefuldiagnostictoolas
nificance, Radiol Clin North Am 32:829–844, 1994. itmayidentifysmallcollectionsofperitonealgasmissedby
Mularski RA, Ciccolo ML, Rappaport WD: Nonsurgical radiography.Still,evenCTmayfailtoidentifypneumoper-
causes of pneumoperitoneum, West J Med 170: itoneuminthepresenceofperforatedviscus,and,attimes,
41–46, 1999. theonlyabnormalitydemonstratedbyCTmaybeperito-
nealfreefluid.
Cross-Reference When radiographs demonstrate pneumoperitoneum
and the clinical picture is compatible with perforated
Emergency Radiology: THE REQUISITES, pp 95, 305.
viscus, there is no need for additional imaging. How-
ever, when patient history and atypical clinical presen-
Comment
tation suggest the possibility of nonsurgical pneumo-
Pneumoperitoneum refers to free intraperitoneal gas col- peritoneum, additional or follow-up imaging may be
lections.Themostfrequentcauseoffreeperitonealgasis useful to exclude lesions requiring surgical intervention,
recent abdominal surgery or other iatrogenic causes of as long as close clinical monitoring is maintained.
peritoneal violation. Among the pathologic causes of
pneumoperitoneum, the most common are spontaneous Notes
visceralperforations,withupto85%ofpatientsexhibiting
pneumoperitoneum.Foremostamongthevisceralsources
areperforatinggastroduodenalulcersfollowedbothsmall-
andlarge-bowelperforationssecondarytovariouscauses
thatincludebowelobstruction,infection,andinfarction.
Acute appendicitis and colonic diverticulitis are com-
mon causes of perforation, yet they are not common
causes of pneumoperitoneum, because either the vol-
umeofgasintheperforatedorganissmall(e.g.,appendi-
citis) or the gas is localized to the site of perforation by
inflammatory reaction (e.g., diverticulitis). Spontaneous
pneumoperitoneum without visceral perforation is an
uncommon yet well-recognized clinical-radiologic entity.
The many causes of ‘‘nonsurgical pneumoperitoneum’’
include, but are not limited to, barotrauma, asthma and
other causes of elevated intrathoracic pressure, collagen
vascular disease, pneumatosis cystoides intestinalis, jeju-
nal and sigmoid diverticulosis, and gynecologic sources
that include pelvic examinations, vaginal douching, and
coitus.
Erectposteroanterior(PA)chestandleftlateraldecubi-
tusabdominalradiographshavebeenconsideredthemost
sensitiveradiographicprojectionsforidentifyingpneumo-
peritoneum,althougherectlateralchestradiographshave
been promoted as more sensitive than erect PA chest
radiographs.Althoughproperlyexposedradiographscan
identify aslittleas 1 to2 mL offree gas, thesensitivityof
radiographsreliesonmaintainingthepatientinthedesired
4
C AS E 2
You are shown images of a blunt trauma patient.
1. What is the diagnosis?
2. What predisposes the patient to spinal injury?
3. What are other features of this disease?
4. What is the most common mechanism producing this injury?
5