Dynamic Radiologyof the Abdomen

FIFTH EDITION

SpringerNew YorkBerlinHeidelbergBarcelonaHong KongLondonMilanParisSingaporeTokyo

Morton A. Meyers

With Contributions by Stephen R. Baker, Alfred S. Berne, Chusilp Charnsangavej,Kyunghee C. Cho, Michiel A.M. Feldberg, Bruce Javors, Hiromu Mori,Michael Oliphant, Catherine Roy, Maarten S. van Leeuwen, Ronald Wachsberg

Dynamic Radiologyof the AbdomenNormal and Pathologic AnatomyFIFTH EDITION

With 1133 Figures in 1796 Parts, 18 in Color

Springer

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To my wife,Bea,

and my children,Richard and Amy

There are some things which cannot be learned quickly, and time,which is all we have, must be paid heavily for their acquiring. They are

the very simplest things; and, because it takes a man’s life to knowthem, the little new that each man gets from life is very costly and the

only heritage he has to leave.

Ernest HemingwayDeath in the Afternoon

The greatest thing a human soul ever does in this worldis to see something. . . . To see clearly is poetry, prophecy,

and religion, all in one.

John RuskinModern Painters

Preface to theFifth Edition

The preface to the first edition of Dynamic Radiology ofthe Abdomen: Normal and Pathologic Anatomy stated thatthis book introduces a systematic application of ana-tomic and dynamic principles to the practical under-standing and diagnosis of intraabdominal diseases. Theclinical insights and rational system of diagnostic analysisstimulated by an appreciation of the dynamic intraab-dominal relationships outlined in previous editions havebeen universally adopted. Literally thousands of scien-tific articles in the literature have attested to their basicprecepts. Formulations and analytic approaches intro-duced in the first edition are now widely applied inclinical medicine so that many of the terminologies, def-initions, and concepts of pathogenesis have solidly en-tered the public domain. These insights lead to the un-covering of clinically deceptive diseases, the evaluationof the effects of disease, the anticipation of complica-tions, and the determination of the appropriate diag-nostic and therapeutic approaches. Spanish, Italian, Jap-anese, and Portuguese editions have encouraged morewidespread application of the principles which in turnhas led to further contributions to our understanding ofthe features of spread and localization of intraabdominaldiseases. These principles have been applied to the fullrange of imaging modalities—from plain films and con-ventional contrast studies to CT, US, MRI and endo–scopic, laparoscopic, and intraoperative ultrasonog-raphy—leading to this fifth edition in 24 years.

In the pursuit of comprehending the pattern, allmethods of investigation have been used, including (a)anatomic cross–sectioning of cadavers frozen to maintainrelationships; (b) cadaver injections and dissections per-formed to determine preferential planes of spread alongligaments, mesenteries and extraperitoneal fascial com-partments; (c) selected clinical cases with the fullest

range of imaging studies including plain films, tomo–grams, and conventional contrast studies; presacral ret–roperitoneal pneumography and peritoneography; sin-ography which occasionally provided serendipitousdisplay of normal and pathologic anatomy akin to an invivo model; and computed tomography, ultrasonog-raphy, nuclear medicine studies, magnetic resonance im-aging, and endoscopic ultrasonography; (d) peritoneos-copy; and (e) surgical operations, surgical pathology andautopsies.

The basic aims in writing this book have not changedfrom the first edition and it is produced in the samespirit as its predecessors. The quest of science has alwayssought the identification of a pattern of circumstances.With this recognition, there follows insight and under-standing into the nature and dynamics of events andthereby their predictability, management, and conse-quences. This book establishes that the spread and lo-calization of diseases throughout the abdomen and pelvisare not random, irrational occurences but rather aregoverned by laws of structural and dynamic factors.

To satisfy these aims, special attention has been givento keeping the book current with clinical and techno-logical advances that have so dramatically altered thepractice of abdominal imaging in the past several years.Six completely new chapters have been added and vir-tually all others have been extensively updated and en-larged. This edition is expanded by more than 180 pagesand more than 520 new illustrations.

Many of the new chapters are by international au-thorities who have pioneered advances in the crucialappreciation and precise recognition of a wide spectrumof intraabdominal diseases. An introductory chapter ongeneral considerations underscores the book’s continu-ing thematic approach based upon anatomic relation-

viii Preface to the Fifth Edition

ships, dynamic factors, and visual perception of the im-age. This is followed by a chapter on clinicalembryology, emphasizing an understanding of diseaseentities which often are only first clinically apparent inthe adult. The manifestations of intraperitoneal air, oftensubtle on plain films but nevertheless highly significant,are precisely described and illustrated. A new chapter isdevoted to oncoradiology and the TNM staging of gas-trointestinal cancers, delineating the normal anatomicmural components by sectional imaging and the extentof intramural and regional neoplastic spread. Otherchapters deal with the discrete identification of the path-ways of lymph node metastases in cancers of the gastro-intestinal and hepatobiliary tracts and the pathways ofregional spread in pancreatic cancer.

Developments in understanding the intraperitonealspread of infections include the normal and pathologicanatomy of the lesser sac. Features of the significance ofthe gastropancreatic plica, the superior and lower reces-ses of the lesser sac, and the imaging features of the di-mensions and relationships of the foramen of Winsloware detailed. The clinical significance of the spread ofinfection via the perihepatic ligaments is greatly ex-panded.

Concepts of the pathways of dissemination of malig-nancies have been highly expanded and richly illustratedwith the full range of imaging modalities. Normal andpathologic anatomy are made graphic by spiral CT withplanar reconstructions, MR, endoscopic ultrasonog–raphy and laparoscopic ultrasonography. The positionand nomenclature of lymph node stations in gastric car-cinoma as classified by the Japanese Research Societyfor Gastric Cancer have been updated and correlation ismade with the TNM staging system. Further advancesin the understanding of the intraperitoneal spread of ma-lignancies include features of seeded perihepatic andsubdiaphragmatic metastases, subcapsular liver metasta-ses, spread to anterior mediastinal lymph nodes, implan-tation on the falciform ligament and within the inter-hepatic fissures, hepatic invasion by advanced gastriccancer, Sister Mary Joseph’s nodule, Krukenberg tumorsof the ovaries, the pathogenesis and differential diagnosisof the omental cake and of peritoneal thickening andenhancement in peritoneal carcinomatosis; instrumen-tal, operative and needle track seeding; hematogeousmetastases to the small bowel from metastatic melanoma,breast carcinoma and bronchogenic carcinoma. Devel-opments and advances in imaging the spread and local-ization of intraperitoneal malignancies are discussed andillustrated. The unifying perspective of the subperito-neal space of the abdomen and pelvis, establishing thediscrete planes of subserous connective tissue and lym-phatics, is extended to the thoraco-abdominal contin-

uum; this holistic concept provides an explanation forwhat has long been thought of as illogical circumstances.

Numerous major developments have also refined ourprecise evaluation of the extraperitoneal fascia andspaces. A new section defines the compartmentalizationof the anterior pararenal space, in keeping with pro-gressive application of embryologic/anatomic circum-stances to clinical imaging. The section on the extra-peritoneal paravesical pelvic spaces and their continuitieswith the abdominal spaces has been refined and ex-panded. Fundamental anatomic characteristics of thefascia and spaces are documented and their clinical rele-vance richly illustrated. These include the potentialmidline communication of the perirenal spaces, the in-ferior apex of the cone of renal fascia, the retromesen-teric plane, the attachment of the adrenal gland to therenal fascia superiorly, and the identification of the twolamellae of the posterior renal fascia. Further enlargedare the discussions and illustrations of the lumbar tri-angle pathway and its relationship to Grey Turner’s signin pancreatitis and retrorenal hemorrhage; and of exten-sion along the perihepatic ligaments and its relationshipto Cullen’s sign. Occasional instances of splenic traumaleading to clinically masked extraperitoneal bleeding areexplained. Staging of renal cell carcinoma is significantlyupdated, with comparison of Robson’s classification andthe TNM system and the value of magnetic resonanceimaging. Perirenal diseases beyond abscesses and hem-orrhage have been expanded to include perirenal me-tastases, lymphoma, extramedullary hematopoiesis andretroperitoneal fibrosis. The anatomy of the iliopsoascompartment is clarified and the features of psoas abscessare illustrated. Controversies regarding rupture of ab-dominal aortic aneurysms with extension of hemor-rhage to the extraperitoneal spaces are resolved.

Other additions include discussions of renocolic fis-tulas; the precise anatomy and importance of the liga-ment of Treitz; characteristic localizing features ofscleroderma, carcinoid and Crohn disease of the smallbowel; and the CT features and differential diagnosis ofinternal paraduodenal hernias.

While diagnostic criteria are emphasized throughoutthe book, there is also discussion of foreseeable compli-cations and appropriate management of many diseaseprocesses.

As in previous editions, great care has been taken withthe layout to give prominence to selected illustrationsand, most importantly, to position the figures as closelyas possible to their citation in the text so that the reader’stime and effort are not wasted referring to pages somedistance apart.

The color atlas details anatomic features of clinicalsignificance.

Preface to the Fifth Edition ix

The references have been considerably expanded andcontinue to include both classic articles and recent ci-tations. They are not restricted to the English languageand, when pertinent, refer to the original descriptions.A lengthy index with cross-references provides imme-diate access to the detailed material presented.

Many persons have contributed importantly to thefifth edition and I thank them sincerely. I wish to expressmy particular appreciation to Angel Arenas, M.D., Hos-pital Universitario “12 de Octubre,” Madrid, Spain; YongHo Auh, M.D., Asan Medical Center, Seoul, Korea; EmilBalthazar, M.D., New York University School of Medi-cine, New York City; James Brink, M.D., Yale UniversityMedical School, New Haven, Connecticut; Gary G.Ghahremani, M.D., Evanston Hospital—NorthwesternUniversity, Evanston, Illinois; Jay P. Heiken, M.D., Mal-linckrodt Institute of Radiology, St. Louis, Missouri;Dean T. Maglinte, M.D., Methodist Hospital, Indiana-

polis, Indiana; Hiromu Mori, M.D., Oita Medical Uni-versity, Oita, Japan; Michael Oliphant, M.D., CrouseHospital, State University of New York, Syracuse, NewYork; Richard C. Semelka, M.D., University of NorthCarolina Hospitals, Chapel Hill, North Carolina; AnnSinger, M.D., Cleveland Clinic Foundation, Cleveland,Ohio, and Francis Weill, M.D., University of BesançonSchool of Medicine, Besançon, France for their contri-butions. Additionally, I wish to express my gratitude tothe contributing authors who have added luster to thisedition.

I am distinctly grateful to Michiel A. M. Feldberg,M.D., Ph.D., University Hospital, Utrecht, Nether-lands, for his selfless cooperation and the stimulatingpleasure of sharing intellectual enthusiasms.

I have submitted this fifth manuscript to Springer-Verlag, confident that their skills have produced anotheredition of high technical quality.

Morton A. Meyers, M.D.Stony Brook, New York

January, 2000

Foreword toFirst Edition

Few books present so fresh an approach and so clear anexposition as does Dynamic Radiology of the Abdomen:Normal and Pathologic Anatomy.

This well-documented, clearly written, and beauti-fully illustrated book details the answers not only to“what is it?” but also “how?” and “why?” Such fun-damental information regarding the pathogenesis of dis-ease within the abdomen reinforces and simplifies ac-curate radiologic analysis. The characteristic radiologicfeatures of intraabdominal diseases are shown to be easilyidentified, expanding the practical application of theterm “pattern recognition.” It certainly is of practicalvalue in daily clinical experience and will be of consid-erable help for further advances.

The traditional dissectional method of learning anat-omy disturbs the intimate relationships of structures.The sectional anatomy presented in this book is theframework for understanding the findings in conven-tional radiology—in plain films and routine contraststudies—as well as in ultrasonography and computed to-mography of the abdomen.

This is not just a review of others’ experiences, but acrystallization of the author’s contributions over the pastseveral years. Dr. Meyers’ concept of dynamic circula-tion within the peritoneal cavity is a breakthrough inour understanding of the spread of intraabdominal dis-ease, particularly abscesses and malignancies. Perito-neography, the opacification of the largest lumen in thebody, offers a potential yield of vast diagnostic infor-mation. The precise definition of the three extraperi-toneal spaces represents a charting of previously unex-plored territory. Awareness of the renointestinal andduodenocolic relationships, the spread of pancreatitisalong mesenteric planes, and the pathways of extrapelvicspread of disease again underscores the practical impor-tance of anatomic features. The approach to the mes-enteric and antimesenteric borders of the small boweland to the haustral pattern of the colon adds a new di-mension to the interpretation of abdominal radiology.

This book confirms Dr. Meyers’ reputation as one ofthe authorities in normal and pathologic radiologicanatomy of the abdomen.

1976 Richard H. Marshak, M.D.Clinical Professor of RadiologyMount Sinai School of MedicineNew York, New York

Foreword toFirst Edition

Dr. Morton A. Meyers indeed has developed a dynamictext relating to radiologic aspects of abdominal disease.But this statement, with its emphasis on radiology, ismisleading. This book is an important reading sourcefor surgeons. Dr. Meyers’ observations have not beenconfined to those arising from a purely radiologic studyof the abdomen. The inclusion of observations based oninjection studies both in the cadaver and in vivo has giventhis work a noteworthy comprehensiveness.

The insights provided by both the atlas of full-pagecolor anatomic cross sections of the abdomen and pelvisand the excellent anatomic-radiologic correlationsfound in the text make the book indispensable. The atlasestablishes the basis for intimate anatomic relationshipswhich are then applied to the practical areas of clinicaldiagnosis and treatment of intraabdominal pathology.

Presentations of these diagnostic and therapeutic con-siderations are enhanced by illustrated discussions rela-tive to the new techniques of ultrasonography and com-puted tomography.

Dr. Meyers’ presentation of this timely informationis valuable, but what makes this book invaluable is thevast personal experience he is able to bring to it. Thisis not “just another” book purporting to give us some-thing new in this important field. I believe the specialapproach given to this subject by Dr. Meyers is trulyinnovative. The radiologist and surgeon looking for thelatest techniques in angiography for the diagnosis andtreatment of massive bleeding form the gastrointestinaltract will not find it here. What they will find is majorhelp in the understanding of, and indeed, therapeuticapproach to a number of common intraabdominal prob-lems, including infection and malignancy.

1976 Lloyd M. Nyhus, M.D., F.A.C.SWarren H. Cole Professor

and Chairman, Department of SurgeryThe Abraham Lincoln School of MedicineUniversity of Illinois at the Medical CenterChicago, Illinois

Contents

Preface to the Fifth EditionForeword to the First Edition by R.H. MarshakForeword to the First Edition by L.M. NyhusContributorsColor Insert

1 General Considerations: Dynamics of Image AnalysisNormal Anatomic Relationships and Dynamic Principles of Pathways of Spread and Localization of DiseaseVisual Factors: Perception of the ImageReferences

2 Clinical Embryology of the Abdomen: Normal and Pathologic AnatomyBruce R. Javors, M.D., Hiromu Mori, M.D., Morton A. Meyers, M.D., and Ronald H. Wachsberg, M.D.Early Development of the Embryo,DiaphragmGastrointestinal Tract

Duodenal Web and Bowel DuplicationEmbryologic Rotation and Fixation of GutVolvulusMeckel’s Diverticulum

Hepatobiliary SystemHepatic Lobar AgenesisEctopic and Accessory GallbladdersCholedochal CystHepatic Duct Diverticulum

Portal Venous SystemPortohepatic Venous ShuntPreduodenal Portal VeinDuctus VenosusAneurysmal Dilation of the Portal VeinAgenesis of the Portal Vein

PancreasAnnular PancreasPancreas DivisumAgenesis of the Dorsal PancreasPancreatic Arteriovenous MalformationPancreatic Cysts

SpleenAccessory SpleenWandering SpleenPolysplenia Syndrome

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xvi Contents

Internal HerniasUrogenital System

Urinary TractGenital System

References

3 Intraperitoneal Spread of InfectionsAnatomic Considerations

The Posterior Peritoneal AttachmentsDetailed Anatomy of the Right Upper Quadrant

Radiologic FeaturesThe Spread and Localization of Intraperitoneal Abscesses

The Sectional and Isotopic Imaging ModalitiesManagementReferences

4 Intraperitoneal Spread of MalignanciesDirect Invasion from Noncontiguous Primary Tumors

Invasion Along Mesenteric ReflectionsInvasion by Lymphatic Permeation

Direct Invasion from Contiguous Primary TumorsIntraperitoneal Seeding

Anatomic FeaturesPathways of Ascitic FlowSeeded SitesDevelopments and Advances in Imaging

Embolic MetastasesMetastatic MelanomaBreast MetastasesBronchogenic CarcinomaRenal Carcinoma

References

5 Staging of Gastrointestinal CancersImportance of Staging

Carcinoma of the EsophagusCarcinoma of the StomachColorectal Carcinoma

Delineation of Normal Mural Components by Sectional ImagingT Staging

T1 StageT2 StageT3 StageT4 Stage

Lymph Node MetastasesReferences

4445455051

575757597979

118124128

131132132166

182192192193193233238239243245245255

265265265266269270272272275275275283284

Contents xvii

6 Pathways of Lymph Node Metastases in Cancer of the Gastrointestinal andHepatobiliary TractsChusilp Charnsangavej, M.D.The Supramesocolic Compartment

Anatomic ConsiderationPeritoneal Ligaments of the LiverPeritoneal Ligaments of the StomachLymphatic Drainage of the Liver and Pathways of Lymph Node MetastasisLymphatic Drainage of the Stomach and Pathways of Lymph Node Metastasis

The Inframesocolic CompartmentAnatomic ConsiderationLymphatic Drainage of the Colon and Pathways of Lymph Node Metastasis

References

7 Manifestations of Intraperitoneal AirKyunghee C. Cho, M.D., and Stephen R. Baker, M.D.Detection of Intraperitoneal AirSupine Abdominal FilmsSupine Film Signs of Pneumoperitoneum

Depiction of Ligaments Protruding into the Peritoneal CavityVisualization of the Peritoneal Surface of Intraabdominal OrgansDetection of Free Air Confined in Specific Peritoneal RecessesRecognition of Free Air Superimposed on the Liver

References

8 The Extraperitoneal Spaces: Normal and Pathologic AnatomyAnatomic Considerations

The Three Extraperitoneal Compartments and Perirenal FasciaeThe Psoas MuscleThe Hepatic and Splenic Angles

Anterior Pararenal SpaceRoentgen Anatomy of Distribution and Localization of CollectionsSources of Effusions

Compartmentalization of the Anterior Pararenal SpaceMaarten S. van Leeuwen, M.D., and Michiel A.M. Feldberg, M.D.

Anatomic ConsiderationsNormal Imaging FeaturesAbnormal Imaging Features

Perirenal SpaceRoentgen Anatomy of Distribution and Localization of Collections

Posterior Pararenal SpaceRoentgen Anatomy of Distribution and Localization of CollectionsClinical Sources of Effusions

Diffuse Extraperitoneal GasRectal PerforationSigmoid Perforation

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309309310310316319326330

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xviii Contents

Extraperitoneal Gas of Supradiaphragmatic OriginDifferential Diagnosis of Small Amounts of Supradiaphragmatic Gas

Psoas Abscess and HematomaThe Extraperitoneal Paravesical Pelvic SpacesCatherine Roy, M.D.

Anatomic ConsiderationsAbnormal Imaging Features

References

9 The Renointestinal Relationships: Normal and Pathologic AnatomyAnatomic Considerations

The Right KidneyThe Left Kidney

Radiologic ObservationsCharacteristic Mass DisplacementsPtosis and RotationInvasive Renal Cell CarcinomaPerinephritis and Renointestinal FistulasRenal Agenesis and EctopiaDirect Intestinal Effects Unique to Renal Ectopia

References

10 The Duodenocolic Relationships: Normal and Pathologic AnatomyAnatomic and Normal Radiologic Features

Abnormal Radiologic FeaturesDefect of Mesocolon with Internal Herniation into Lesser SacMasses Within the Mesocolic LeavesEffect upon the Descending Duodenum by Carcinoma of the Hepatic FlexureDuodenocolic FistulasEffect of Gallbladder Disease on the Duodenocolic RelationshipsDuodenocolic Displacements from Right Renal MassesEffect on Colon of Mass Arising in Descending DuodenumInframesocolic Extension of Neoplasm of Third DuodenumAcute PancreatitisDuodenojejunal Junction: Relation to Colon

References

11 Intestinal Effects of Pancreatitis: Spread Along Mesenteric PlanesAnatomic ConsiderationsEffects of Pancreatitis on the Colon: Spread Along the Transverse Mesocolon

Hepatic FlexureTransverse Colon and Splenic Flexure

Effects of Pancreatitis on the Duodenum, Small Bowel, and Cecum: Spread Along Small Bowel MesenteryDuodenumSmall Bowel and Cecum

References

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565565569569569584

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Contents xix

12 Pathways of Regional Spread in Pancreatic CancerChusilp Charnsangavej, M.D.Anatomy of the Pancreas

Vascular AnatomyLymphatic AnatomyPancreatic Nerve Plexus

Imaging StudiesCT Anatomy of the Pancreatic Head

Pathways of Regional Spread in Pancreatic Cancer

Local Organ InvasionVascular InvolvementNodal Metastasis

Perineural InvasionConclusion

References

13 The Subperitoneal Space: Normal and Pathologic AnatomyMichael Oliphant, M.D., Alfred S. Berne, M.D., and Morton A. Meyers, M.D.

Embryologic ConsiderationsAnatomic Considerations

Ventral Mesentery DerivativesDorsal Mesentery DerivativesLateral ContinuityContinuity with the Female Organs

Abnormal Imaging Features

References

14 The Small Bowel: Normal and Pathologic AnatomyAnatomic ConsiderationsNormal Radiologic Observations

Axis of the Root of the Small Bowel MesenteryUndulating Changeable Nature of Coils of Bowel LoopsIdentification of Mesenteric and Antimesenteric Borders of Small Bowel Loops

Abnormal Radiologic FeaturesDiverticulosis of the Small IntestineMeckel’s DiverticulumSclerodermaIntestinal Duplication

Seeded MetastasesHematogenous MetastasesCarcinoid TumorsRegional EnteritisLymphomaIntramural and Mesenteric Bleeding

References

595

595596597598598598599

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605

607

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635635636636636640644644646646650651651652654657657663

xx Contents

15 The Colon: Normal and Pathologic AnatomyAnatomic Considerations

Classification of Organization of Haustral RowsNormal Radiologic ObservationsAbnormal Radiologic Features

Lesions Within the Gastrocolic LigamentLesions Within the Transverse MesocolonDistinction Between Intraperitoneal and Extraperitoneal ProcessesDiverticulosis and Diverticulitis

SummaryReferences

16 Internal Abdominal HerniasParaduodenal Hernias

Anatomic ConsiderationsClinical FeaturesRadiologic and Arteriographic Features

Internal Hernias Through the Foramen of WinslowPericecal HerniasIntersigmoid HerniasTransmesenteric and Transmesocolic HerniasHernias Through the Falciform LigamentRetroanastomotic HerniasReferences

17 Pathways of Extrapelvic Spread of DiseaseAnatomic ConsiderationsRadiologic FindingsReferences

Index

665667669670675675681683692704708

711712712713713731737738739744744746

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763

Contributors

Stephen R. Baker, M.D.Professor and ChairmanDepartment of RadiologyUniversity Hospital C320UMD New Jersey Medical School150 Bergen StreetNewark, NJUSA

Alfred S. Berne, M.D.Professor of RadiologySUNY Health Science Center750 East Adams StreetSyracuse, NYUSA

Chusilp Charnsangavej, M.D.Professor of RadiologyDepartment of Diagnostic RadiologyThe University of Texas M.D. Anderson Cancer Center1515 Holcombe BoulevardHouston, TXUSA

Kyunghee C. Cho, M.D.Professor of RadiologyDepartment of RadiologyUniversity Hospital C320UMD New Jersey Medical School150 Bergen StreetNewark, NJUSA

Michiel A.M. Feldberg, M.D., Ph.D.Professor of RadiologyDepartment of RadiologyUniversity Hospital UtrechtHeidelberglaan 100Utrecht 3584 CXNetherlands

Bruce Javors, M.D.Chief of G. I. RadiologyVice-ChairmanDepartment of RadiologySt. Vincents Hospital and Medical CenterNew York, NYUSA

Hiromu Mori, M.D.Professor and ChairmanDepartment of RadiologyOita Medical UniversityHasama-MachiOita 879-55Japan

Michael Oliphant, M.D.Chief of Radiology and Medical DirectorDepartment of Medical ImagingCrouse Hospital736 Irving AvenueSyracuse, NYUSAandClinical Professor of RadiologySUNY Health Science CenterSyracuse, NYUSA

Catherine Roy, M.D.Professor of RadiologyChef de ServiceService de Radiologie BLes Hopitaux Universitaires de Strasbourg—BP426F-67091 Strasbourg CedexFrance

Maarten S. van Leeuwen, M.D., Ph.D.Department of RadiologyUniversity Hospital UtrechtHeidelberglaan 100Utrecht 3584 CXNetherlands

Ronald Wachsberg, M.D.Associate Professor of RadiologyDepartment of RadiologyUniversity Hospital C320UMD New Jersey Medical School150 Bergen StreetNewark, NJUSA