WHO Manual of Diagnostic Imaging: Radiographic Anatomy and Interpretation of the Chest

The WHO
manual of
diagnostic
imaging


RadiogRaphic
anatomy


and inteRpRetation
of the chest and
the pulmonaRy


system


ISBN 92 4 154677 8


W
H


O
m


a
n


u
a


l O
f d


ia
g


n
O


stic
im


a
g


in
g


R
a


d
Io


g
R


a
ph


Ic
a


N
a


to
m


y
a


N
d


IN
teR


pR
eta


tIo
N


o
f th


e c
h


eSt a
N


d
th


e pu
lm


o
N


a
R


y
Sy


Stem


WHO


Who in collaboration with the international commission for Radiologic


education (icRe) of the international society of Radiology (isR) and other


members of the global steering group for education and training in


diagnostic imaging is creating a series of “manuals of diagnostic imaging”.


the full series of manuals will primarily cover the examination techniques


and interpretation of conventional diagnostic X-ray procedures. these


manuals will replace and update the WHO Manual of Radiographic Inter-


pretation for General Practitioners and the WHO Manual of Radiographic


Technique.


the present volume in the series, the manual Radiographic Anatomy and


Interpretation of the Chest and the Pulmonary System, provides an ex-


haustive description of radiographic normal anatomy as well as the most


common pathologic changes seen in the chest including trauma, tumours,


congenital and developmental disorders.


Backed by high-quality reproduction of radiographs, this manual will


prove essential reading to general practitioners, medical specialists,


radiographers and radiologists in any medical settings, although focusing


specifically on needs in small and mid-size hospitals.




K2


The WHO manual
of diagnostic imaging
Radiographic Anatomy and Interpretation
of the Chest and the Pulmonary System


Editors
Harald Ostensen
Holger Pettersson


Authors
Stephen M. Ellis


Christopher Flower


Published by the World Health Organization
in collaboration with the


International Society of Radiology




ii • THE WHO MAnuAl OF dIAgnOSTIC IMAgIng


K2


WHO Library Cataloguing-in-Publication Data


Ellis, Stephen M.


The WHO manual of diagnostic imaging : radiographic anatomy and interpretation of the chest and the pulmonary
system / Stephen M. Ellis, Christopher Flower ; editors: Harald Ostensen, Holger Pettersson.


(WHO manuals of diagnostic imaging)


1.Radiography, Thoracic—methods 2.Lung—radiography 3.Manuals I.Flower, Christopher. II.Ostensen,
Harald. III.Pettersson, Holger. IV.Title V.Series.


ISBN 92 4 154677 8 (NLM Classification: WF 975)


© World Health Organization 2006


All rights reserved. Publications of the World Health Organization can be obtained from WHO Press, World Health Orga-
nization, 20 Avenue Appia, 1211 Geneva 27, Switzerland (tel: +41 22 791 2476; fax: +41 22 791 4857; email: bookorders@
who.int). Requests for permission to reproduce or translate WHO publications—whether for sale or for noncommercial
distribution—should be addressed to WHO Press, at the above address (fax: +41 22 791 4806; email: permissions@who.
int).


The designations employed and the presentation of the material in this publication do not imply the expression of any
opinion whatsoever on the part of the World Health Organization concerning the legal status of any country, territory, city
or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Dotted lines on maps represent
approximate border lines for which there may not yet be full agreement.


The mention of specific companies or of certain manufacturers’ products does not imply that they are endorsed or recom-
mended by the World Health Organization in preference to others of a similar nature that are not mentioned. Errors and
omissions excepted, the names of proprietary products are distinguished by initial capital letters.


All reasonable precautions have been taken by the World Health Organization to verify the information contained in this
publication. However, the published material is being distributed without warranty of any kind, either express or implied.
The responsibility for the interpretation and use of the material lies with the reader. In no event shall the World Health
Organization be liable for damages arising from its use.


The named authors alone are responsible for the views expressed in this publication.


Printed in Singapore




Contents


Chapter 1 Introduction 1


Chapter 2 The normal CXR 3
Technique 3
lateral 5
Anatomy 7


Chapter 3 How to read a CXR 15
The silhouette sign 15
Suggested scheme for reading a frontal CXR 16
Review areas 20
Pitfalls 27
Buttons 32
ECg tabs 33
Hair braids 34
Film/screen artefacts 34
Film kinking during processing 36


Chapter 4 Pattern recognition 37
Collapse 37
Consolidation 41
ground glass opacity 43
Masses 43
nodules 46
lines 48
Cavities 51


Chapter 5 Abnormalities of the thoracic cage and chest wall 53
Pectus excavatum 53
Kyphosis 55
Tumours in bone 56
Cutaneous nodules 58
Soft tissue asymmetry 59
Sickle cell disease 61


Chapter 6 lung tumours 63
CXR features of malignant tumours 63
CXR features of benign tumours 67
Bronchal carcinoma 68
non-mass like tumours 71
Pleural tumours 71
The solitary pulmonary nodule 72
Further imaging 72 K2


iii




Chapter 7 Pneumonias 73
Bacterial pneumonia 73


Chapter 8 Chronic airways disease 85
Asthma 85
Chronic bronchitis 86
Emphysema 88
Bronchiectasis 91


Chapter 9 diffuse lung disease 95
Fibrosis 95
lymphangitis carcinomatosa 97
lAM 97
lCH 98
Pulmonary sarcoid 99
Hypersensitivity pneumonitis (HP) 102


Chapter 10 Pleural disease 105
Pneumothorax 105
Effusion 109
Empyema 113
Haemothorax 114
Pleural calcification 115
Mesothelioma 117


Chapter 11 left heart failure 119
Cardiomegally 119
Interstitial oedema 121
Blood diversion 122
Consolidation 123
Septal lines 123
Effusions 123


Chapter 12 Cardiac 125
Coarctation of the aorta 125
Fallot’s tetralogy 126
Cardiomegally 127
Pericardial effusion 128
Pericardial calcification 129
Ventricular aneurysm 129
Aortic aneurysm 130


Chapter 13 Pulmonary embolic disease 133


Chapter 14 Mediastinal disease 135
Mediastinal tumours 135
Hilar masses 137
lymphadenopathy 140
Mediastinal haemorrhage 141
Mediastinal abscess 142


Chapter 15 Trauma 143
Further reading 147


iv • COnTEnTS


K2




K2


v


Foreword


Modern diagnostic imaging offers a vast spectrum of modalities and techniques, which enables us
to study the function and morphology of the human body in details that approaches science
fiction.


However, it should be noticed that even in the most advanced imaging department in the economi-
cally privileged parts of the world, 70–80 % of all clinically relevant questions may be solved by
using the two main cornerstones of diagnostic imaging, which are radiography (X-ray) and
ultrasonography.


It should also be remembered that thousands of hospitals and institutions worldwide do not have
the possibilities to perform even these fundamental imaging procedures, for lack of equipment
and/or diagnostic imaging skills.


Therefore, WHO in collaboration with the International Commission for Radiologic Education
(ICRE) of the International Society of Radiology (ISR) is creating a series of “WHO Manuals of
Diagnostic Imaging”, developed under the umbrella of the Global Steering Group for Education
and Training in Diagnostic Imaging. Among the members of this group are the major regional and
global societies involved in diagnostic imaging, including the International Society of Radiology
(ISR), the International Society of Radiographers and Radiological Technologists (ISRRT), and the
World Federation for Ultrasound in Medicine and Biology (WFUMB).


The full series of manuals will primarily cover the examination techniques and interpretation of
radiography, in a later stage also ultrasonography. It is meant for health care personnel who, in their
daily work, are responsible for producing and interpreting radiographs, be it radiologists or other
medical specialists, general practitioners, or radiological technologists working in rural areas.


The manuals are authored by experts in each field, covering the experience, knowledge and needs,
which are specific for different regions of the world.


It is our sincere hope that the manuals will prove helpful in the daily routine, facilitating the diag-
nostic work up and hence the treatment, to the best benefit for the patient.


Geneva, Switzerland and Lund, Sweden, December 2005


Harald Ostensen
Holger Pettersson




K2




chapter 1


Introduction


The following text aims to provide an aid to the interpretation of the chest radiograph (CXR).
This is not a comprehensive account of all possible chest diseases but a descriptive text to help
identify the way in which chest pathology is manifested and diagnosed on CXR. The initial chapters
deal with interpretive skills and pattern recognition and the later chapters demonstrate specific
pathologies.






K2




CHAPTER 2


The normal CXR


Technique
The range of densities one is attempting to image on a chest radiograph (CXR) is larger than at
any other site in the body, ranging from very dense bone to very low-density air filled lungs. As a
result, the quality of the CXR is very dependent on the technique used in its production.


High kV


• In order to form an X-ray image, the tissue being imaged must absorb some X-rays but enough
must pass through to expose the film.


• It was standard practice to produce a CXR using a tube voltage of 50–70 kV, such images have
considerable contrast but fail to show up to a third of the lungs “hidden” behind the heart and
diaphragm.


• Using 120–140 kV produces a spectrum of X-ray energies that are higher and therefore more
penetrating. In this way a greater number of X-rays pass through the denser parts of the chest,
i.e. the mediastinum, and therefore give more detail both of the mediastinum and the heart.
Above 140 kV radiographic contrast becomes significantly reduced.


Air gaps


• X-rays are not only absorbed in the body they are also scattered. This process alters the direction
of travel of the X-ray causing image un-sharpness; only X-rays passing in a straight line cast an
accurate shadow of the chest on the X-ray film.


• Placing an air gap between the patient and the X-ray film increases the chance that the scattered
X-rays will “miss” the X-ray film and therefore not affect image quality (Fig 2.1).


Figure 2.1
The X-ray beams originating from the X-
ray source on the left are shown passing
through a subject on the way to exposing
the film on the right. The beams are
scattered but miss the film due to the air
gap.


• The amount by which the image of the chest is magnified on the X-ray film is dependent on how
far the subject is from the film and how divergent the X-ray beams are. Therefore, when using
an air gap technique the X-ray source should be around 3–4 m from the film.




• THE WHO mAnuAl Of diAgnOsTiC imAging


K2


Grid


• An alternative and more commonly used method of reducing scatter is the placement of a lead
grid between the patient and the film.


• The grid is made up of many strips of X-ray absorbing lead place closely together and angled in
such a way that only the X-rays travelling in a particular direction, corresponding to that of a
straight line between the X-ray tube and the film, are allowed through, scattered X-rays are
absorbed by the lead strips. A fine vibration of the grid ensures that the strips of lead in the grid
do not cast noticeable shadows on the film (Fig 2.2).


Figure 2.2
This time the subject is separated from the film by a grid that
stops the scattered X-rays exposing the film.


• Using a grid enables the subject to be placed against the X-ray cassette so that the divergence of
the X-ray beam is less significant and the X-ray source can be closer to the cassette, around 2 m,
therefore not requiring a dedicated room. However, the air gap technique is felt to produce
superior images.


PA/AP


• A CXR taken in the radiology department is taken with the patient standing erect in front of
and facing the cassette containing the X-ray film.


• The X-ray tube is positioned behind the patient hence the X-rays pass from posterior to anterior
(PA).


• For patients confined to bed or chair, the PA technique is not possible, therefore the X-ray film
is placed behind the patient and the X-ray tube in front so that the X-rays pass from anterior to
posterior (AP).


• In general, AP CXRs are taken with a shorter X-ray tube to film distance compared to a PA film
due to practical limitations.


• There are marked differences in the CXR that can be attributed entirely to the technique used.


• The heart is an anterior organ in the chest and its size is magnified on an AP view due to both
the increase in divergence of the incident X-rays (the X-ray source being closer to the film) and
the increase in distance between the heart and the film when compared to the PA technique. This
magnification may make numerous mediastinal structures appear abnormally enlarged.


• On AP films, the clavicles cast a broader shadow and typically overlay the apices making inter-
pretation of these areas difficult (Fig 2.3).


• In general, the AP film should be interpreted with caution.




K2


THE nORmAl CXR •


Figure 2.
AP CXR (left image) and PA CXR (right image) of an adult male taken 1 day apart. note the apparent
difference in cardiac size and lung volumes and the loss of clarity in the apices.


Figure 2.
Annotated lateral CXR illustrating the anatomy.


Lateral
• The better visualization of the mediastinal structures due to a high kV technique reduces the


necessity for routine lateral views.


• A lateral view provides clearer visualization of the area anterior to the mediastinum and posterior
to the diaphragms and may help interpretation of an abnormality seen on a frontal view
(Fig 2.4).


• If a low kV technique is used a lateral is necessary to image the areas behind the heart and
hemi-diaphragms.


• Other pathology better appreciated on the lateral CXR is right middle lobe or lingularr collapse
and/or consolidation, which may be missed on a frontal CXR due to the orientation of the X-ray
beam (Fig 2.5).




• THE WHO mAnuAl Of diAgnOsTiC imAging


K2


• Conventional radiography uses a combination of a light sensitive film placed against an X-ray
absorbing screen that converts X-ray photons to visible light (scintillation).


• Only around 5% of the CXR image is derived from the direct effect of X-rays on the film, the
rest is due to the screen, which enhances the efficacy of the incident X-rays by producing many
photons of light for each X-ray photon.


• The advantage of this combination is in a reduction of X-ray dose required to form an image.


• The disadvantage is that the light produced will spread out from the point at which the X-ray
arrived and expose a larger area of the film creating some “un-sharpness” compared to an image
derived entirely from incident X-ray exposure.


• This is one example of the many compromises made in radiology between radiation dose and
image quality.


• The response of the film/screen combination to radiation exposure is not linear throughout the
range of exposures. There is an approximate linear portion in the mid exposure range but very
non-linear response at each end of the spectrum.


• As the range of tissue densities in the chest is so large the range of exposure that the film/screen
combination has to depict is also large and regions of the CXR corresponding to exposures towards
the end of the spectrum will have poor contrast.


• The CXR is taken such that as much information as possible is depicted in the mid range of
exposure. A high kV approach generates a narrower spectrum of X-ray exposure but retains tissue
distinction hence creating a better CXR.


Figure 2.
frontal and lateral CXRs of an adult female with right middle lobe collapse. The white arrows indicate the areas
of abnormal opacity. On the lateral view one can appreciate that the collapsed lobe is at an angle to the
direction of the X-ray beam for the frontal view as the lobe collapses down onto the major fissure, the result is a
vague increase in opacity on the frontal view.




K2


THE nORmAl CXR •


Figure 2.
graph of film density against exposure for digital
and film/screen radiography. The curved line
indicates the limited range over which film/screen
radiography produces useful contrast.


• Digital radiography uses either a storage phosphor plate, which is read by a laser after the exposure,
or by converting the incident X-ray directly into an electrical signal; both techniques have a linear
relationship between optical density and exposure and therefore are not restricted in the same
way as film/screen radiography (Fig 2.6).


kV, mA


• X-rays are produced when fast moving electrons impact on a tungsten target.


• The energy of the X-rays produced is dependent on the energy of the electrons.


• The energy is given to the electrons by accelerating them between the electron source (a piece of
heated metal) and the target by applying a voltage across these two pieces of metal (the tube
voltage).


• The electrons have a negative charge and are attracted to the positively charged target.


• The tube voltage determines the electron energy and thus the spectrum of X-ray energies pro-
duced, the higher the voltage the higher the X-ray energy.


• The amount of X-rays produced is dependent on both the kV and the mA.


• The mA is defined by the rate per second at which electrons hit the target in the X-ray tube. The
product of tube current and exposure time mAs is used in the calculation of X-ray dose.


• Doubling the kV from 60 kV (low kV) to 120 kV (high kV) will increase the amount of X-rays
produced four fold, therefore the mAs should be reduced to a quarter of its original value to leave
the amount of X-rays produced, and thus the exposure, unchanged.


Anatomy
• A CXR is a two dimensional representation of a three-dimensional structure. As a result the CXR


includes many overlapping structures.


• A thorough knowledge of the anatomy should enable you, on most occasions, to identify an
abnormality and place it in the correct area of the chest.




• THE WHO mAnuAl Of diAgnOsTiC imAging


K2


Figure 2.9
Coronal (left) and sagittal (right)
reconstructions from CT scanning
demonstrating the anatomy of the
costophrenic angles (black arrows).


Figure 2.
The hilar points are marked on the left image. On the right image the pulmonary arteries and pulmonary
veins have been superimposed. The hilar point is formed by the outer margins of the upper lobe pulmonary
veins and the lower lobe pulmonary arteries as they cross. note the left main pulmonary artery loops over the
left main bronchus therefore the left basal pulmonary artery crosses the left upper lobe pulmonary vein higher
on the left than on the right and the hila point is also normally higher on the left.


Figure 2.
Coronal and sagittal reconstructions from a CT scan of the chest. The right minor fissure is marked by white arrows
(vertical up), the right major fissure by white arrows (vertical down) and the left major fissure between the horizontal
black arrows. note on the coronal image the lung between the minor and major fissures, the right middle lobe, is
adjacent to the right heart border. On the left the lung above the left oblique fissure, the left upper lobe or more
specifically the lingular, lies adjacent to the left heart border. The lower lobes are adjacent to the hemidiaphragms.


Hilar points (Fig 2.8)


Costrophrenic and cardiophrenic angles (Figs 2.9, 2.10)


Lobar anatomy on CXR (Fig 2.7)




K2


THE nORmAl CXR • 9


Figure 2.10
Coronal reconstruction from CT scanning demonstrat-
ing the anatomy of the cardiophrenic angles (black
arrows).


Figure 2.11
mediastinal lines, a- posterior junctional line (where the lungs meet posteriorly-seen superior to the sternal
notch), b- right paratracheal stripe (normally up to 5 mm with a bulge inferiorly where the azygos vain crosses
the right main bronchus), c- anterior junctional line (where the lungs meet anteriorly- not present above the
sternal notch), d- azygo-esophageal line formed where lung lies adjacent to the right margin of the oesopha-
gus and extending up to the point where the azygos vein arches anteriorly over the right main bronchus to
drain into the superior caval vein (sVC).


Junctional lines (Fig 2.11)




10 • THE WHO mAnuAl Of diAgnOsTiC imAging


K2


Figure 2.12
left image shows mediastinal contours, the right
image is a coronal reconstruction of the
mediastinum from CT scanning; a- aortic
outflow tract, b- right atrium, c- pulmonary
artery outflow, d- left atrial appendage, e- left
ventricle.


Figure 2.1
The arrows mark the paraspinal lines representing the soft tissue that lies adjacent to the spine. On the right there is
very little soft tissue and the line is very close (~2 mm) from the spine. On the left the aorta courses down the anterior
left aspect of the spine causing the paraspinal line to be further from the spine. The relevance of these lines is in the
detection of paraspinal pathology such as tumours or spinal fracture causing haematoma. Bulging/widening of these
lines suggests paraspinal pathology.


Mediastinal contour (Fig 2.12)


Paraspinal lines




K2


THE nORmAl CXR • 11


The upper abdomen is included on a CXR and the relevant anatomy is described. Upper abdominal
pathology may be evident on a CXR (Fig 2.14).


Figure 2.1
Coronal reconstruction from CT imaging demonstrating the abdominal anatomy included on a CXR. note the
liver (white arrow vertical down), the stomach (white arrow diagonally up), the splenic flexure of the colon
(white arrow diagonally down), the pancreas (white arrow horizontal), the spleen (black arrow horizontal), the
kidneys (black arrows diagonally down).


Figure 2.1
Right accessory fissure (black arrows) unlike the minor fissure this does not reach the hilum, azygos fissure
(white arrows) formed during the migration of the azygos vein and contains 4 layers of pleura.


Normal variants


Accessory fissures (Fig 2.15).




12 • THE WHO mAnuAl Of diAgnOsTiC imAging


K2


Figure 2.1
frontal CXR of an adult with a right-sided aortic arch (white arrows). in this case associated with fallot’s tetralogy.


Right sided arch (Fig 2.16)




K2


THE nORmAl CXR • 1


Figure 2.1
A child with dextrocardia and situs invertus (note the ng tube—black arrows), the clip (white arrow) is from
repair of a patent ductus arteriosus found on the right in this child as such patients also have a right sided
aortic arch.


Dextrocardia (Fig 2.17)




1 • THE WHO mAnuAl Of diAgnOsTiC imAging


K2


Figure 2.1
Cervical ribs, larger on the left (white arrow) can be distinguished from hypoplastic first ribs as they arise from the C7
vertebral body the transverse processes of which point downwards as opposed to those of the T1 vertebral body that
point upwards.


Cervical ribs (2.18)




K2


15


CHAPTER 3


How to read a CXR


• AirabsorbsnoX-raysandthelungcontainsmainlyair.Adeflatedadultlungisaboutthesizeof
afist.


• BeyondtheproximalairwaystheonlystructuresvisibleinanormallungonaCXRarethevessels
duetothecontrastbetweenbloodandairfilledlungs;thelunginterstitiumandthewallsofthe
bronchiolesaretoofinetobeseen.


• InterpretationoftheCXRdependstoagreatextentondetermininghowthevisualizationofthe
vesselshasbeenaltered.


• Ifthevesselsareobscuredthecauseisopacificationoftheadjacentlung.


• Ifthevesselsareofreducedcalibrethereisareductioninbloodflow.


• Ifthevesselsareof increasedcalibre,anincreaseinbloodfloworperhapspressuremaybethe
reason.


• Theabsenceofvesselsinaeratedlungsuggestslungdestruction(e.g.emphysema).


• Spreadoutnormalcalibrevesselssuggestoverexpansionofthelung(e.g.accommodatingcollapse
ofanotherlobe).


The silhouette sign
• When there are tissuesofdifferentdensitynext to eachother there is a suddenchange in the
amountofX-rayspassingthroughthebody,thisresultsinasuddenchangeinthedensityonthe
resultingX-rayfilm.Inthiswayasilhouetteofthemoredensestructureiscreated.


Figure 3.1
The simulated shadow cast by a 3D CT reconstruction of the
mediastinum demonstrates the principal behind the silhouette of the
mediastinal contours.




16 • THE WHO mAnuAl Of DiAgnOsTiC imAging


K2


• Thepresenceofthesilhouetteenablesthemarginsofastructuretobeseenbut,moreimportantly,
the lossof a silhouette that shouldbevisible indicates that the lowerdensity tissuenowhasa
higherdensity.


• Inthelungs,thetermsilhouettesignreferstointerfaces(boundaries)betweensofttissuestructures
and aerated lung.When a silhouette is lost itmeans that either the lung in that region is no
longeraerated,(e.g.consolidation/collapse)orthatithasbeenreplacedbydifferenttissuessuch
asatumour.


• Thepositionoftheabnormalitycausingthelossofthesilhouettecanbelocalizediftheorigin
ofthesilhouetteisknown,e.g.theaeratedrightmiddlelobecreatesthesilhouetteoftheright
heartborderandthelingualthatontheleft.


Suggested scheme for reading a frontal CXR
• EveryoneshoulddevelopaschemeforreadingtheCXR.Astherearemanyoverlappingstructures,
manypossiblepathologiesandsignificantblindspots,athoroughstrategyisessentialandwith
practicecanbeperformedsurprisinglyquickly.


• Weoutlineonestrategyandexplainthereasoningbehindit.IthighlightstheareasoftheCXR
thatrequireparticularscrutinyandthosethatareoftenoverlooked.


• AssoonasaCXRisviewedasnapshotdecisionastowhetherthefilmisnormalorabnormalis
made.Ifanabnormalityismissedduringthissnapshot,ithasinalllikelihoodbeenseenbutincor-
rectlyinterpreted.Allofthishashappenedinafewsecondsandisnotunderconsciouscontrol.


Figure 3.2
The bars depict the intensity of X-rays in relation to the edge of the descending aorta (image on left) and the left
heart border (image on right). note the resulting lines on the CXRs and the fact that these lines are visible overlying
the other opacities (left upper lobe collapse—left image, left lower lobe abcess—right image).




K2


HOW TO READ A CXR • 17


• The eye is readily deceived and a CXR should be approachedwith as few preconceptions as
possible.


• Evenifasnapshotimpressionidentifiesanabnormality,otherabnormalitiesmayhavebeenmissed
andtheinterpretationofaCXRshouldstillbeapproachedsystematically.


• Thefollowingschemecoversthefilmbutisnotdependentonanatomicalboundaries.Youmay
developyourownscheme,butbearinmindthepotentialpitfallsdetailedhere.


• Checkthenameanddateofthefilm.


• Checkthefilmthecorrectwayround(sidemarker).


• IsthefilmPAorAP(seeearlier).


• Isthesubject,erect,semi-erectorsupine.


Begininthetoplefthandcornerofthefilm(patientsrightshoulder).


A. Scanfromlefttoright


Figure 3.3
Check the soft tissues and bones of the shoulder girdle
(clavicles, scapulae) and neck. Are there any bony lesions
(fractures, deposits, cervical ribs, joint abnormalities, etc),
soft tissue masses and is the trachea normal (position,
calibre)? Compare the apices of the lung. Are they of the
same density?


B. Returntothetoplefthandcornerrepeatingtheaboveobservations.


Figure 3.4




18 • THE WHO mAnuAl Of DiAgnOsTiC imAging


K2


C. Scanfromtoplefttobottomleft


Figure 3.5
Check the soft tissues of the chest wall, the lateral aspect
of the ribs, the peripheral lung, pleura and costophrenic
angle.


D. Movetothemidrightdiaphragmandscanuptotherightapex


Figure 3.6
Check behind the diaphragm, there is enough space here
to “hide” a 7–8 cm tumour. Observe the parenchyma of the
right lung. Are the vessels visible and of normal calibre? if
the vessels are obscured this suggests abnormal opacity in
the adjacent lung.


E. Fromtherightapexscandowntherightmediastinalcontour


Figure 3.7
The right paratracheal stripe should be visible. is the
mediastinal contour visible? Check the position of the hilar
point, which should be at the level of the lateral extent of
the right 6th rib. End at the right cardiophrenic angle, the
inferior vena cava lies here.




K2


HOW TO READ A CXR • 19


F. Scanupthecentreofthefilm


G. Scandowntheleftmediastinalcontour


H. Nowmove to themid lefthemidiaphragm.Thegastric fundusandthe spleenareunder the
diaphragm.


Figure 3.8
note the structures that should be visible behind the heart,
particularly the spine, paraspinal region and azygo-
oesophageal line (often overlooked). is the mediastinum
central, the carina normal, the trachea normal in position
and calibre?


Figure 3.9
The aortic knuckle, aorto-pulmonary window, the left hilar
point (slightly higher than the right hilar point) and the left
contour of the heart (pulmonary outflow tract), left atrial
appendage and left ventricle. End at the left cardiophrenic
angle.


Figure 3.10
scan up the film looking at the lung parenchyma ending in
the left apex.




20 • THE WHO mAnuAl Of DiAgnOsTiC imAging


K2


I. Movetotheleftshoulderandscandowntheleftperipheryofthechest


J. Finally,comparethelungparenchymalefttorightintheupper,midandlowerzones


Figure 3.11
Concentrate on the peripheral lung, ribs and soft tissues of
the chest wall.


Figure 3.12
This scheme is easy to follow and includes the main areas in
which abnormalities are missed.


Review areas
ThereviewareasarethosepartsoftheCXRinwhichanabnormalitycaneasilybeoverlookedand
thereforerequireparticularattention(Fig3.13).


Figure 3.13
The review areas.




K2


HOW TO READ A CXR • 21


The apices


• Attheapicesofthe lungthere is little lungparenchymacomparedtotheamountofoverlying
softtissueandbone.


• Theanteriorpartofthefirstriboverliestheposteriorpartsofthefirst3to4ribsandallthese
relativelydensestructurescontributetoanoverallincreasedopacityintheapexattheexpenseof
definitionofthelungparenchyma.


• Attheextremeapex,itisnotunusualtohavea“cap”ofpleuralthickeningthatisofnoclinical
significance.


• Thebestwaytoapproachtheapicesisbycomparingthetwosides.Isthereadifferenceinopacity
andifso,canthisbeexplainedbytheoverlyingribs?


• Ifnot,thensomeparenchymalabnormalityshouldbesuspectedandinthefirstinstance,alor-
doticviewshouldbeperformed(Fig3.14).


Figure 3.14
On the left image there is increased density in the right apex (white arrow) but this may be due to overlap of
anterior 1st rib, clavicle and posterior 4th rib. The lordotic view (right image) projects the 1st rib and clavicle off
the chest revealing the underlying nodule (white arrow), a carcinoma that was subsequently resected.


The thoracic inlet


• Thisisareviewareabecauseitiseasilyoverlooked.


• Thetracheadominatesthethoracicinlet;theotherstructuresinthisareaarethevesselsarising
fromtheaorticarchandtheveinsfeedingintothesuperiorvenacava.


• Abnormalitiesinthethoracicinletareusuallyduetoextrasofttissuesuchaslymphadenopathy
or thyroid enlargement or intrinsic abnormality (narrowing or dilatation) of the trachea
(Figs3.15,3.16).




22 • THE WHO mAnuAl Of DiAgnOsTiC imAging


K2


Figure 3.15
frontal CXR on the left, on the right is a magnified
view of the upper mediastinum. note the tracheal
stenosis secondary to prolonged intubation (black
arrows).


Figure 3.16
frontal CXR of an adult female with a goitre. note the deviation of the trachea (black arrow) marked on the magni-
fied view. The CT image shows the enlarged left thyroid lobe causing deviation of the trachea.


Overlying the scapulae


• The region of lung overlying the scapula appears to be of slightly increased density, therefore
subtledensitychangessuchassofttissuenodulesunrelatedtothescapulaecouldbeoverlooked
(Fig3.17).


Figure 3.17
frontal CXR demonstrates a soft tissue nodule (black arrow)
projected over the medial border of the right scapula which
can easily be overlooked.




K2


HOW TO READ A CXR • 23


Costophrenic angles


• Thecostophrenicangleshouldbe“sharp”, i.e.thediaphragmshouldformanacuteanglewith
thechestwall.


• “Blunting”ofthecostophrenicangle,indicatesthatthereissofttissueorfluidwherethelowest
limitsofthelungshouldbe.Usuallythisisduetopleuralfluidorthickening(3.18).


Figure 3.18
Blunting of the left costophrenic angle in a young man with a “long” chest indicates the possibility of a
spontaneous pneumothorax. The subtle lung edge (white arrows) is marked on the magnified image.


• Septallines(“KerlyBlines”)arebestseenatthecostophrenicanglesandareeasilyoverlooked;
theyindicateinterstitiallunginfiltrates,usuallyduetoheartfailure,butalsoconsiderlymphangitis
carcinomatosa(seepatternrecognition>lines).


Under the hemidiaphragms


• Lunglesionslyingposteriorlyinthelungbasesareprojectedbeneaththehemidiaphragmsand
mayproveverydifficulttosee(Fig3.19).




24 • THE WHO mAnuAl Of DiAgnOsTiC imAging


K2


• The liver liesunder the righthemidiaphragm.Therefore lucencybeneath thishemidiaphragm
suggeststhepresenceoffreegaswithintheabdomen.


• The colonmay interpose between the liver and thediaphragmmimicking free gas, but sharp
medialand lateralextremities to thegas shadowwould favour freegas,as that foundwithina
tubularstructuresuchasthecolon,willnotformthesesharpmargins(Fig3.20).


Figure 3.19
A large (7 cm) mass is sited
posteriorly in the right
lower lobe projected behind
the right hemidiaphragm
(margins marked by
arrows).


Figure 3.20
frontal CXR of a post-operative patient. note the visibility of both sides of the right hemidiaphragm (white arrows) due
to free gas in the abdomen. As a result, the superior surface of the liver is visible (black arrow).




K2


HOW TO READ A CXR • 25


• Ontheleft,thenormallyairfilledgastricfundusliesbeneaththediaphragm.


• If there is freegasonthe left,onlythediaphragm,about3–4mmthick,separates thefreegas
fromthe lung.Air in thegastric fundus is separated fromthe lungby thediaphragmand the
gastricwall.


• Again,sharpmarginstothegasshadowincreasethelikelihoodoffreegas.


• Ifuncertaintyremains,alateraldecubitusAXRviewshouldresolvetheissue,asthefreegaswill
traveltotheleastdependentarea,i.e.theuppermostlateralmarginoftheabdomen.


Behind the heart


• AwelltakenCXRwilldemonstratethethoracicspineprojectedthroughthecardiacshadow.A
“soft”orunderexposedfilmwherethespineisnotvisibleshouldbereadwithcautionasasignifi-
cantportionofthethoraxhasnotbeenadequatelyvisualized.


• Abnormalitiesofthethoracicspinemaybeapparent,theremaybemassesorswellingrelatedto
theparaspinallines(seeanatomy).


• Thedescendingaortaisprojectedbehindtheheartandtheleftedgeofthisshouldbevisible.


• Ahiatusherniaoroesophagealdilatationwillbeprojectedbehindtheheartandoftencontains
gas(Fig3.21).


Figure 3.21
Hiatus hernia. note on the magnified image the lateral margins of the hernia (white arrows) and the air fluid
level (black arrow).


• The azygo-oesophageal line should be identified.An abnormal contour suggests amediastinal
mass,usuallylymphadenopathybutalsoconsideroesophagealpathology(Fig3.22).




26 • THE WHO mAnuAl Of DiAgnOsTiC imAging


K2


• Leftlowerlobecollapsepartiallyhiddenbehindtheheartisoftenoverlooked(Fig3.23).


Figure 3.22
frontal CXR of an adult female with lymphoma. note the soft tissue mass in the aorto-pulmonary window (white
arrow) also seen on the CT image (inset) and the bulging of the azygo-oesophageal line (black arrows) due to sub
carinal lymphadenopathy.


Figure 3.23
CXR of an infant demonstrates left lower
lobe collapse. The lateral margin of the lobe
is marked (arrows). note the increased
density behind the heart and the loss of the
medial portion of the left hemidiaphragmatic
silhouette.


The cardiophrenic angles


• Apoorlydefinedopacityisoftenseenatthecardiophrenicanglesduetopericardialfatpads.


• Abnormalsofttissueintheregionisreadilyoverlooked.


• Apericardialfatpadwillnotbeseparablefromthecardiacoutline,andbeingcomposedoffat,
itshouldbeoflowdensity.


• The margins of the pericardial fat pad are usually indistinct, if at all discernable, such that
opacity in thecardiophrenicanglewithdefinedmargins isunlikely to representpericardial fat
(Fig3.24).




K2


HOW TO READ A CXR • 27


Pitfalls
Pseudo-pneumothorax


• Foldsintheskincantrapaircreatingasofttissue/airinterfaceandthusalineontheCXRwhich
canmimicthelungedgeofapneumothorax.


• ThisisusuallyseenonAPfilmstakenwiththepatientlyingagainsttheX-raycassette.


• Thekeypointsarethattherewillbelungmarkingsbeyondtheassumedlungedgeandtheline
willceasemoreabruptlythanalungedgewould(Fig3.25).


Figure 3.24
A 2 cm carcinoma projected over the left cardiophrenic angle. The margins of the nodule are marked by
arrows in the magnified view.


Figure 3.25
CXR taken in intensive care unit. note endotracheal tube, internal jugular line, swann gantz catheter and a
balloon pump in the aorta. An apparent lung edge is marked (black arrows) but careful scrutiny reveals lung
markings beyond this edge (white arrow). The edge is formed by a fold of skin on the patients back as the
patient is sitting semi-erect and the film cassette is against his back.




28 • THE WHO mAnuAl Of DiAgnOsTiC imAging


K2


Patient rotation


• AcorrectlycentredCXRwillprojectthespinousprocessesofthethoracicspinemidwaybetween
themedialendsoftheclavicles.


• As the clavicles are anterior structures and the spinous processes are posterior structures, any
rotationof thepatient, i.e. to the leftor right,will result in themovementof the clavicles in
relationtothespinousprocesses.


• Asaresulttheprojecteddistancesbetweenthemedialendsoftheclavicleandthespinousprocess
willincreaseonthesidetowhichthepatientisrotated(Fig3.26).


Figure 3.26
frontal CXR with subject rotated to the left. note an enlarged heart and small left pleural effusion. The left
hemithorax is darker than the right due to the rotation. note the distance between the medial end of the
right clavicle and the spinous process of T2 (distance a) is less than the distance between the spinous process
and the medial end of the left clavicle (distance b) indicating rotation to the left as demonstrated in the 3D
reconstruction.


• Rotationmaycauseanincreaseinthetransradiancy(blackness)ofthelungonthesidetowhich
thepatientisrotated,whichshouldbetakenintoaccountwhenreadingthefilm.


• Rotationwillalsoaltertherelativeappearanceonthehilaandcanmimichilarasymmetryand
theprojectionofthesternumoverthehilummaybeevident(Fig3.27).


Figure 3.27
The subject is rotated to the
left and as a result the
sternum is projected over the
left mediastinal contour
(white arrow). The sternum is
outlined on the magnified
view.




K2


HOW TO READ A CXR • 29


Poor inspiration


• Iftherearelessthan6anteriorribsprojectedabovethehemidiaphragmsthenthefilmhasbeen
takenwithapoorinspiratoryeffort.


• Thelowerzonevesselsbecomecrowdedandthereisanoverallincreaseinlowerzoneopacity.


• Thehilaarecompressedandappearmorebulky(Fig3.28).


Figure 3.28
Two frontal CXRs of the same patient taken on the same day. for the CXR on the left the patient has made a poor
inspiratory effort. note the apparent bulkiness of the hila, increased density in the lower zones and the enlarged
cardiac silhouette. The CXR on the right taken in full inspiration demonstrates that the patient’s CXR is normal and
previous apparent abnormalities were due to poor inspiratory effort (images courtesy of D m Hansell).


Nipple shadows


• Whenseenassymmetrical,nippleshadowsrarelycausediagnosticdifficulties.


• ItisnotuncommonthatonlyonenippleisevidentonaCXR.


• Featuresthatsuggestashadowisduetoanippleareapositionappropriatetothebreastshadow
andwell-definedmarginsononlytwosidesusuallyinferiorandlateral(Fig3.29).


Figure 3.29
left image-right nipple shadow
marked (black arrow). note relative
position to right breast margin
(white arrows). Right image is a
magnified view of the left nipple
shadow (white arrows). note the
indistinct superior medial margin
(black arrow).




30 • THE WHO mAnuAl Of DiAgnOsTiC imAging


K2


• Ifuncertainty remains, a repeatfilmwith thenipplesmarkedby something radio-opaquewill
resolvetheissue(Fig3.30).


Figure 3.30
Top left image is a frontal chest radiograph, 2 areas magnified demonstrate possible nodules, the asymmetry
on this image raises the possibility that at least one of the shadows represents a nodule. A repeat film bottom
right with nipple markers resolves the issue demonstrating that both are nipples.


Pulmonary venous confluence


• Sometimes the pulmonary veins draining the right lung combine prior to entering the left
atrium.


• Theresultisopacityvisiblebehindtherightsideoftheheartmimickingamass(Fig3.31).




K2


HOW TO READ A CXR • 31


• Thecluestoitsidentityaretheabsenceofamedialmargin,confluencewiththeleftatriumand
thedrainingpulmonaryveins.


• NeverthelesstheappearancecanbequitecompellingandalateralCXRshouldhelpresolvethe
issue.


The azygos lobe


• Duringembryologicaldevelopment, theazygosveinmaycoursethroughtheupperdeveloping
lungon itsway to taking itsposition, archingover the rightmainbronchus into the superior
venacava.


• Afoldofpleura,azygosfissure,accompaniestheveinandcreatestheazygoslobeaspartofthe
upperlobe,whichmayhaveitsownbronchus.


• Theazygosfissurerunsacurvedcoursefromtheazygosnobtotheapexandshouldnotbecon-
fusedwithpathology.


• Pathologymaybe confined to the azygos lobe causingopacitywith a verywelldefined lateral
margin,whichcouldeasilybeconfusedwithrightupperlobecollapse(Fig3.32).


Figure 3.31
frontal and lateral CXR of an adult male. The pulmonary venous confluence mimics a mass behind the right
heart (white and black arrows).




32 • THE WHO mAnuAl Of DiAgnOsTiC imAging


K2


The manubrium sterni


• If thepatient is slightlyrotated,particularlytotheright, the lateralmarginofthemanubrium
becomesvisibleandmayappeartorepresentpara-tracheallymphadenopathy.


• Theappearanceswhencarefullyobservedwillreflectawelldefinedangularedgeofappropriate
shape(Fig3.33).


Figure 3.32
left image shows opacity in the right apex with a well defined lower border (white arrows). This could easily be
mistaken for a collapse right upper lobe but the minor fissure (black arrow) is visible. The left image follows
bronchoscopic removal of a mucous plug in the airway leading to an azygos lobe. The azygos fissure (white arrows)
and minor fissure (black arrow) are marked.


Figure 3.33
left image suggests possible right
paratracheal mass. The right
images demonstrate the outline of
the manubrium causing this
appearance.


Artifacts


Ingeneralsurfaceartefactscanbeidentifiedforwhattheyarebycarefulscrutiny.However,ifdoubt
remainsarepeatfilmwithallpossibleartefactualobjectsremovedshouldresolvetheissue.


Buttons
• When solitary, buttons can look convincingly like nodules particularly due to the soft tissue
densitytheymimic.


• Thepresenceofothernoduleselsewhereofexactlythesamesizeoroutsidethelungparenchyma
areusefulcluesandmostbuttonswillhavediscernableholesinaregularpattern(Fig3.34).




K2


HOW TO READ A CXR • 33


Figure 3.34
frontal CXR of an adult male with an apparent nodule in the left upper/mid zone (horizontal black arrows). On
closer inspection, the regular shape of this “nodule” and the presence of four equally spaced holes (diagonal
black arrows) confirms that this is a button.


ECG tabs
• Commonlyleftonthepatient’schestfordaysonend,theseartefactscanappeartobeconsistent
overaseriesoffilmsandhaveadisconcertingsofttissuedensityappearance.


• Asforbuttonstheappearanceoftheseoutsidethelungisausefulclueandthewell-definedcurved
cornersarecharacteristic.


• Again,repeatfilmwithtabsremovedwouldresolvetheissue(Fig3.35).


Figure 3.35
left image suggests 2 large soft tissue masses, the magnified image on the right shows these to be ECg tabs.




34 • THE WHO mAnuAl Of DiAgnOsTiC imAging


K2


Hair braids
• Whenmultiple,hairbraidsdonotposeadiagnosticproblembutsinglebraidsthatareshortor
foldedcanoverlaytheapicesgivingtheappearanceofparenchymalopacity.


• Theclueisintheextensionofthisopacitybeyondtheapextooverlaytheneckwhere,unlikea
truesofttissuemass,itsmarginswillstillbedefinable.


• Inaddition,theairtrappedinabraidmaybeseenasradiolucentlines(Fig3.36).


Figure 3.36
left image shows increased opacity in the right apex (white arrow) in a subject being screened for TB. Right
magnified image highlights the thin lucent lines within the hair braid (small black arrow) and the hair band
(large black arrow).


Film/screen artefacts
• Foreignbodiessuchasdirt,dustandhaironthefluorescentscreenwillcastsharpshadowson
theX-rayfilmas theyareadjacent to thefilmcompared to the structures in the lung thatare
furtherfromthefilmandthereforehavelesssharpmargins(Fig3.37).




K2


HOW TO READ A CXR • 35


Figure 3.37
A magnified portion of a frontal CXR demonstrates the curvilinear opacity (black arrows) that appears far too
sharply defined to represent an abnormality in the chest. note the difference in sharpness between the
artefact and the ribs. The artefact has been caused by a hair trapped between the film and the screen. note
also reticulation and septal lines (white arrows) due to lymphangitis carcinomatosis.




36 • THE WHO mAnuAl Of DiAgnOsTiC imAging


K2


Film kinking during processing
• Atthepointatwhichafilmisbeinggripped,particularlyusingthethumbandonefinger,the
filmmaybecomekinked.Ifthisoccurspriortodevelopinganartefactiscreated(Fig3.38).


Figure 3.38
frontal CXR of an adult male. The curved marks appearing on the film in two places (black arrows) are due to the film
kinking when gripped between the thumb and fingers.




K2


37


CHAPTER 4


Pattern recognition


Collapse
Right upper lobe (RUL) collapse


• TheRULcollapsesforwardsandthelowerlobeexpandstofillthespacecreated,therefore,aerated
lowerlobeliesposteriortothecollapsedRULandextendstotheapex.


• Ona frontalCXR,RULcollapse isobservedasan increase indensity in therightupperzone
withalowermargindefinedbythehorizontalfissure.


• Ifthecauseofthecollapseisacentralmassobstructingthebronchus,abulgeatthehilumgives
an“S”shapetotheinferiormarginofthecollapse,the“GoldenSsign”(Figs4.1,4.2).


Figure 4.1
Complete right upper lobe collapse. The white arrows mark
the minor (horizontal) fissure that separates the right upper
lobe from the right middle lobe. As the upper lobe collapses
medially and forwards the fissure also moves. The upper lobe
comes to lie adjacent to the upper mediastinum causing
widening of the right paratracheal stripe (black arrow) and
deviation of the trachea to the right due to volume loss. Note
the difference in transradiancy between the two hemithoraces
as the lower lobe and middle lobe on the right have expanded
to fill the space left by the upper lobe and the vessels are
therefore more widely spread.


Figure 4.2
Right upper lobe collapse due to a
central obstructing tumour mass.
The minor fissure is raised (white
arrow) indicating some collapse of
the right upper lobe, There is
increased opacity in the right apex
and volume loss evident with
deviation of the trachea to the right.
The medial edge of the collapsed
right upper lobe is seen (horizontal
black arrow) and the cause for the
collapse is the mass at the right
hilum (diagonal black arrow). The
combination of partial collapse and
a central obstructing mass creates a
curve to the minor fissure termed
the “Golden S sign”.




38 • THE WHO mANuAl Of diAGNOSTiC imAGiNG


K2


Left upper lobe (LUL) collapse


• LiketheRUL,theLULcollapsesforwards,butintheabsenceofahorizontalfissureontheleft,
thereisnoclearinferiormarginofthecollapse.


• Asontheright,thelowerlobeexpandstofillthespaceleavingaveillikeopacityintheleftupper
zone.


• Thelingulamaybeincludedinthecollapsecausinganincreaseinopacityovermorethanhalf
ofthelefthemithoraxwithobscurationoftheleftheartborder.


• Classically, LUL collapse obscures the silhouette of the aortic knuckle but this may not be
apparent(Fig4.3).


Figure 4.3
left upper lobe collapse. left image: increased veil like opacity in the left mid and upper zone with almost normal
transradiancy in the left apex (black arrow-diagonally down) as the left lower lobe expands to fill the space left by
the collapsing upper lobe. Note loss of the left heart border due to lingular collapse (black arrow diagonally up). The
collapse in this case is so complete that the aortic knuckle silhouette is preserved (horizontal black arrow); this is
often obscured in lul collapse. Right image: CT section demonstrates the interface between the collapsed lul and
the mediastinal fat (black arrow) and the major fissure (white arrow). Note the lul collapses forwards leaving space
posteriorly into which the left lower lobe expands.


Right middle lobe (RML) collapse


• TheRMLcollapsesinferiorlyontotheobliquefissurecausingdepressionofthehorizontalfissure,
whichwillnolongerbeapparentonthefrontalCXR.


• There are no definable margins that relate to RML collapse making it a difficult sign to
interpret.


• Thereisincreaseddensityadjacenttoandobscuringtherightheartborder.


• AlateralCXRwilldemonstratethecollapseclearlyandtheappearancesonthefrontalCXRmay
beaccentuatedbytakingalordoticview(i.e.theX-raybeamangledupwardsfromthefrontor
downwardsfromtheback)(Fig4.4).




K2


PATTERN RECOGNiTiON • 39


Right lower lobe (RLL) collapse


• TheRLLcollapsesmediallycausingincreaseddensitybehindandadjacentto,butnotobscuring,
therightheartborder.


• Usually,thelateralmarginofthecollapseiswelldefined,demarcatedbytheobliquefissure,and
therewillbeevidenceofrightlowerzonevolumelosswithdepressionofthehilapointonthe
right.


• TheRULexpandstooccupythespace(Fig4.5).


Figure 4.4
Right middle lobe collapse. left image: frontal CXR demonstrates an ill-defined opacity medially in the right
lower zone (white arrow) obscuring the right heart border. Right image: lateral CXR demonstrates a thin
wedge shaped opacity that corresponds to the Rml. Note the lobe collapses downwards, bringing the minor
fissure (black arrows) close to the major fissure.


Figure 4.5
Right lower lobe collapse. The
lateral margin of the collapsed
Rll (black arrows) is formed by
the major fissure, which has been
pulled into the line of the X-ray
beam by the Rll as it collapses
posteriorly and medially. Note
preservation of the right heart
border (white arrow) and loss of
the right diaphragmatic
silhouette.




40 • THE WHO mANuAl Of diAGNOSTiC imAGiNG


K2


Left lower lobe (LLL) collapse


• Like theRLL the LLL collapsesmedially leaving awell-defined lateralmargin, obscuring the
medialaspectofthelefthemi-diaphragmaticsilhouetteandcausingincreaseddensitybehindthe
heart.


• Volumelossresultsindepressionofthelefthilum,amoreverticalcoursefortheleftmainbron-
chus,shiftofthemediastinumtotheleftandcompensatoryexpansionoftheLUL(Fig4.6).


Figure 4.6
left lower lobe collapse. The collapsed lll creates a triangular density behind the heart with a straight lateral
border (diagonal black arrows). Note the loss of the silhouette of the medial portion of the left hemidia-
phragm (vertical black arrows), shift of the lower mediastinum to the left so that the right heart border
overlies the spine (white horizontal arrow), reduction in the number of visible vessels on the left due to
compensatory over-expansion of the left upper lobe (vertical white arrows).


Whole lung collapse


• Anobstructionoftheleftorrightmainbronchuscancausecollapseofanentirelung.


• Theappearanceisdramaticandmimicsthe“whiteout”seeninaverylargepleuraleffusionbut
thepresenceofmediastinalshifttothesideoftheopacityindicatescollapseasthecauserather
thananeffusionthatismorelikelytoshiftthemediastinumtheoppositeway(Fig4.7).




K2


PATTERN RECOGNiTiON • 41


Figure 4.7
Complete collapse of the right lung secondary to an obstructing tumour in the right main bronchus (white
arrow). Note the complete opacification of the right hemithorax combined with mediastinal shift to the right.


Consolidation
• Consolidation describes the filling of the air spaces of the lung withmaterial other than air,
namely,water,pusorblood.


• TheCXRappearancesreflectthelossofair,hencetheincreaseinopacity.


• Thevesselsarenolongeradjacenttotheaeratedlungandbecomeinvisibleorindistinct.


• Thesmallairwaysstillcontainingairandsurroundedbyopacifiedlungbecomevisiblecreating
air bronchograms(Figs4.8,4.9).




42 • THE WHO mANuAl Of diAGNOSTiC imAGiNG


K2


Figure 4.8
An area of consolidation in the lingula (note the loss of the left heart border silhouette) with air-bronchograms visible
(black arrows) and pulmonary vessels marked (white arrows).


Figure 4.9
CT image demonstrating the creation of air bronchograms in consolidated lung. The walls of the smaller airways are
too thin to see on CXR but with adjacent opacified lung, the tubular airway stands out clearly (black arrows).




K2


PATTERN RECOGNiTiON • 43


Ground glass opacity
• Asthelungtissuebecomesfilledwithinfiltrates,whetherwater,pus,bloodorfibrosis,there is
anincreaseinthedensityofthatlung,whichwillappearonaCXRasanopacity.


• Ifthereisinsufficientalveolarfillingtogenerateair-bronchogramsortoomuchinterstitialfilling
todisplayreticulation,theresultistermedgroundglassopacity.


• AreasofgroundglassopacityonCXRareusuallytheresultofaninflammatoryprocess,suchas
infection,orduetodevelopingpulmonaryoedema.


• Thepulmonaryvesselsbecomeobscuredbutairbronchogramsarenotseen(Fig4.10).


Figure 4.10
left image demonstrates ground glass opacity in the lingula (white arrow) obscuring the left heart border
(black arrow). The right image taken 6 weeks following antibiotic therapy, demonstrates resolution of what
was pneumonia.


Masses
• Amassisdefinedasanopacitymeasuring3cmormoreindiameter;anopacitylessthan3cm
indiameteriscalledanodule. Amassmaydestroytheadjacentlungaswithinvasivelesions,and
haveilldefinedmargins,ordisplacelungasitgrowsandhavewelldefinedmargins.


• The identification of themargins of themass depends upon the presence of adjacent aerated
lung.


• Ifthemassisboundedbychestwall,consolidatedlungoradjacentnormalsofttissuestructure,
therelevantmarginwillbeindistinct(Fig4.11).


Figure 4.11
frontal CXR of an
adult male with an
ill-defined mass in
the left mid zone.
Even on the
magnified image,
the margins are
indistinct due to
infiltration of this
surrounding lung
parenchyma by the
primary
adenocarcinoma.




44 • THE WHO mANuAl Of diAGNOSTiC imAGiNG


K2


• Ifthemedialmarginisvisible,butthelateralmarginisindistinct,themassisprobablypleural
based(Fig4.12).


Figure 4.12
left image demonstrates a pleural based mass, in this case mesothelioma. Note on the magnified image the
well defined medial margin (white arrows) where the mass is adjacent to the lung and the merging of the
upper border with the chest wall (black arrow).


Figure 4.13
frontal CXR of an adult with an empyema. Note the opacity in the right lower zone with preservation of
vascular markings (black arrow). The CT image demonstrates the loculated collection causing the opacity.


• Amassarisingfromthemediastinumwillhavenodefinablemedialmarginbuttendstohavea
well-definedlateralmarginasitdisplacesadjacentlung(Fig4.14).


• Massesmayhidebehind thediaphragm(Fig4.15) in theposterior costophrenic recess, in the
apicesandinthepara-spinalregionprojectedbehindtheheart(Fig4.16).


• Pleuralbasedmassesatthefrontorbackofthechestmayonlybevisibleasanincreaseindensity
onthePACXRwithpreservationofthelungmarkingsthatwouldbeobscurediftheabnormality
werewithinthelung(Fig4.13).




K2


PATTERN RECOGNiTiON • 45


Figure 4.14
left image is the frontal CXR and the right image a axial CT image of a large mediastinal mass, in this case
lymphoma. Note the well-defined lobulated lateral margin and loss of the right heart border silhouette (black
arrow). Also, note that the anterior position of this mass leaves the hilar vessels unobscured.


Figure 4.15
The left image is a frontal CXR where a 4 cm mass lying in the right lower lobe is projected behind the right
hemidiaphragm (black arrow) and easily overlooked. The inset demonstrates the lesion on a CT image and the
magnified views highlight the outline of the mass on the CXR (black arrows/grey circle).


Figure 4.16
Two masses (colorectal metastases) are evident
on the CXR, one projected behind the right
hemidiaphragm (horizontal black arrows) and the
other projected behind the heart (vertical/
diagonal black arrows). The inset demonstrates
the lesions on CT scanning.




46 • THE WHO mANuAl Of diAGNOSTiC imAGiNG


K2


Nodules
• Measuringlessthan3cmindiameter,nodulesmaybesolitaryormultiple.


• Multiplenoduleshaveawidedifferentialdependingonnodulesize,densityandtheclinicalstate
ofthepatient(Table4.1).


Table 4.1 Causes of multiple nodules


Size Density Distribution Disease


<2 mm Soft tissue Widespread miliary TB
fungal infection
(more in bases) Hypersenstitivity
pneumonitis
mid zones Coal miner’s
pneumoconiosis
mid zones Sarcoid
Basal fibrosing alveolitis
High density Widespread Haemosiderosis
Siderosis
Stannosis
Alveolar microlithiasis
mid zones Silicosis
Barytosis
2–5 mm Soft tissue Widespread and discrete Carcinomatosis
lymphoma
Sarcoidosis
Widespread and tend Pneumonia (e.g.TB)
to confluence
Pulmonary oedema
Basal and tend Hypersensitivity
to confluence pneumonitis
Peripheral and tend fat emboli
to confluence
features distribution disease
>5 mm Calcification, cavitation Widespread metastases
dependent on cell type
Cavitation common Widespread Abscesses
Cavitation and calcification upper lobes Coccidiomycosis
few in number, may calcify Any Histoplasmosis
Cavitation, well defined Widespread Wegener’s
Cavitation lower zones, peripheral Rheumatoid nodules
Cavitation, calcification, Any Caplan’s syndrome
background
pneumoconiosis
Well defined, lobulated Any Arterio-venous
malformation




K2


PATTERN RECOGNiTiON • 47


• Nodulesareparticularlydifficulttoidentifywithcertaintywhentheyareofasimilardiameter
tothesmallvesselsinthelung.


• Scrutinyof theperipheryof the lung in the spaceboundedby the anterior andposterior ribs
wherethereisnooverlyingribandvesselsaretoosmalltobevisibleandshouldnormallyreveal
nodiscernableanatomicstructures.


• Nodulesidentifiedinthisregionarereal(Figs4.17,4.18,4.19).


Figure 4.17
multiple small nodules identified on frontal CXR are, at 2–3 mm similar in size to small vessels. Peripherally in
the magnified view the nodules marked with white arrows could be confused for vessels but those marked
with black arrows lie where vessels are not normally visible. The CT image confirms the presence of multiple
small nodules, in this case a fungal infection in an immunocompromised patient.


Figure 4.18
frontal CXR demonstrating numerous
nodules and masses. These are metasta-
ses from a seminoma and have clearly
defined borders.




48 • THE WHO mANuAl Of diAGNOSTiC imAGiNG


K2


Figure 4.19
frontal CXR of a case of previous chicken pox pneumonia. Note the multiple calcified nodules of varying size, very
dense on CXR despite their small size.


Lines
TherearefourbasictypesoflinesontheCXR.


Band shadowing


Bandshadowing isusually1–3cmthickand2–4cmlongandmostcommonlyseentowardsthe
lungbases.Parenchymalbandsresultfromatelectasis(collapse)ofasub-segmentalportionoflung
usuallyfoundfollowingfocalpneumonia,pulmonaryembolismorupperabdominalsurgery(Fig
4.20).




K2


PATTERN RECOGNiTiON • 49


Curvilinear


Curvilinearlinesarefoundinbullousemphysema.Theentiremarginofthebullaisrarely,ifever,
seenbutpartsofthewallmaycrosstheX-raybeamatthecorrectangletocreatealineontheCXR
(Fig4.21).


Figure 4.20
frontal CXR of an adult male following recent abdominal surgery. Note the development of band atelectasis
in the right mid zone (white arrows) and the subclavian intravenous line on the left (black arrow).


Figure 4.21
frontal CXR of a patient with bullous emphysema. Note the curvilinear lines (white arrows) indicating the walls
of the bullae.




50 • THE WHO mANuAl Of diAGNOSTiC imAGiNG


K2


Septal lines (Kerley A, B lines)


Septal lines are caused by the accumulation of fluid or othermaterial in the interlobular septa.
KerleyBlinesarefoundattheperipheryofthelungbases.Theyare1–2cminlengthandextend
atrightanglesfromthepleuralsurface.Thecommonestcausesareleftheartfailure(Fig4.22)and
lymphangitiscarcinomatosa(Fig4.23,Table4.2).


Figure 4.22
frontal CXR of a patient with left heart failure. Note the double right heart border due to the right margin of the
enlarged left atrium (black arrow). The 2 magnified views are of the costophrenic angles and septal lines are marked
(white arrows).


Figure 4.23
A patient with right lower
lobe collapse secondary
to primary lung carci-
noma. There is mediasti-
nal adenopathy and
reticulation in the right
lower zone (white arrow)
indicating an interstitial
infiltrate. in addition,
there are numerous
septal lines (vertical black
arrows) and a small
pleural effusion (diagonal
black arrow) secondary to
lymphangetic congestion
from tumour infiltration.


Table 4.2 Causes of septal lines


left ventricular failure
Pneumoconioses
lymphangitis carcinomatosa
Sarcoid (rare)


KerleyAlinesarelongerandareseeninthemidzones.Theyreflectthesameinterstitialprocess
extendingintothemoreproximalinterlobularsepta.




K2


PATTERN RECOGNiTiON • 51


Reticulation


Reticulation represents thickening of the lung interstitium and is difficult to identify with
confidenceonaCXR.Thepatternconsistsofcriss-crossingfinelines,whichmustbedistinguished
fromthenormalvascularpattern.Potentialcausesarefluidaccumulationintheinterstitiumasin
pulmonaryoedema,orthickeningduetocellularorfibroticprocesses.Astheinterstitiumextending
to the surface of the lung is usually the first to become affected, reticulation is often better
appreciatedattheperipheryofthelungontheCXRandtheirregularityofthelungadjacentto
soft tissue structures interfereswith the silhouette signresulting ina roughor ill-definedmargin
(Fig4.24).


Figure 4.24
frontal CXR of a patient with idiopathic pulmonary fibrosis (cryptogenic fibrosing alveolitis). Note the diffuse
reticulation and the loss of clarity of the heart borders (black arrows).


Cavities
Acavityisthedevelopmentofanairspacewithinsolidtissuewhetheramass(Fig4.25)orconsoli-
dated(Fig4.26)/infarctedlungandthereforetendstohaveathickerwallthanfoundincystsor
bullae.


Figure 4.25
large cavitating lesion
(squamous cell carcinoma)
in the left mid zone with
an associated chest wall
mass (black arrow – rib
metastasis).




52 • THE WHO mANuAl Of diAGNOSTiC imAGiNG


K2


Figure 4.26
An adult female patient with a cavitating pneumonia. Note the fluid level within the cavity (black arrow). The top
CXR was that at presentation, and the bottom CXR was taken 1 month later, following antibiotic therapy.


Cavitiesmaycontainairfluidlevelsandcavitationwithinconsolidatedlungmaybeobscuredby
theadjacentabnormallungparenchyma.




K2


53


CHAPTER 5


Abnormalities of
the thoracic cage and
chest wall


Pectus excavatum
• Pectusexcavatumisadevelopmentalabnormality that results inbackwarddisplacementof the
sternumandaresultingreductionoftheantero-posteriordiameterofthechestinthemidline.
This causes a shift of the heart to the left and an abnormal angle to the ribs adjoining the
sternum.


• OntheCXR,theposterioraspectsof theribsaremorehorizontal thanusualandtheanterior
ribsaremoreverticalgivingafigure“7”appearance.


• Achange in theorientationof the anterior chestwall and the shiftingof theheart to the left
result in the lossof clarityof the rightheartborder andanunusually straight edge to the left
heartborder(Fig5.1).


• PectusexcavatumoccursasanisolatedphenomenonbutisalsostronglyassociatedwithMarfan’s
syndrome.


Figure 5.1
Frontal CXR of a patient with pectus excavatum. Note the shift of the lower mediastinum to the left and an
unclear right heart border (horizontal black arrow), a straight left heart border (diagonal black arrow) and
horizontal posterior ribs with more vertical anterior ribs the figure “7” sign (white arrows). The CT image is of
a different patient with pectus excavatum demonstrating the depressed sternum (black arrow).




54 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


K2


Scoliosis


• Scoliosisiscurvatureofthespineinthecoronalplane.


• Thenormalspineisstraightinthecoronalplanebutallowssomedegreeoflateralflexionateach
thoracicvertebraljoint.


• ThesimplestformofscoliosisasseenonaCXRisphysiologicalandrelatedtothepatient’sposi-
tionatthetimeoftheCXR.


• Thismaybeduetopoorpositioningbytheradiographerbutisalsoanormalresponsetounilateral
chestpainwherethescoliosisisduetoflexionofthespinetowardthesideofthepain.


• Scoliosismayalsobecongenitaloraresultofspinalpathologysuchasvertebralfracture,tumour
orinfection.


• OnaCXR,thespineshouldbevisible,andswellingofapara-spinal lineinassociationwitha
scoliosisindicatessignificantpathology(Fig5.2).


Figure 5.2
Frontal CXR of a patient with metastatic breast carcinoma. The presence of lymphangitis carcinomatosis is noted. The
magnified image demonstrates the right para-spinal soft tissue mass (black arrows) and the resulting scoliosis is indicated
with a thin dark line. The inset images are axial and sagittal images from a mRi of the same patient. Note the para-spinal
soft tissue on the upper image and the change in signal in the vertebral bodies, evident in the sagittal view, confirming
metastases.




K2


AbNORmAliTiEs OF THE THORACiC CAgE ANd CHEsT WAll • 55


Kyphosis
ThespineinthesagittalplaneisnotstraightbutformsadoubleSshape.Mechanically,thisenables
thespinetoabsorbimpactsalongitslength,e.g.whilstrunning,byminordegreesofflexionand
extensionateachintervertebraljoin.Thethoracicspinehasaphysiologicalkyphosis(Fig5.3).


Figure 5.3
sagittal reconstruction of the chest demonstrating the normal kyphotic curvature of the thoracic spine.




56 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


K2


Tumours in bone
• Primary tumours of the thoracic cage are rare;most bone tumours aremetastases ormultiple
myeloma.


• Metastasesmaybesclerotic(producingincreaseddensity)(Fig5.5)orlytic(whenthereisrarefac-
tionanddestructionofthebone)(Fig5.6).


• Lytic bony lesions of the ribsmay be difficult to appreciate on aCXR as superimposed lung
vesselscanreadilygivetheimpressionofvariationsindensitymimickinglyticdeposits.Thelateral
aspects of the ribsnotprojectedover lung and lucencies in the ribs at these sites indicate the
presenceoflyticlesions.


• Theclaviclesandscapulaeareeasiertoscrutinisebutareoftenoverlooked(Fig5.7).


Figure 5.4
Frontal and lateral CXR of an adult female. Note the comparative small volume of lungs on the PA view due to an
increase in the PA diameter of the chest.


• Anteriorwedgecollapseofthoracicvertebraecausesaccentuationofthethoracickyphosisandis
commonlyfoundintheelderly.


• Thesignificancetothepatientisarestrictioninchestexpansionthatmayaffecttheirrespiratory
function.


• Ona frontalCXR,thekyphosisdecreases theperceivedsizeof thechest throughreduction in
thecranio-caudaldimension,andthemandiblemaycometooverlaytheupperchest.


• Thelateralviewisideallysuitedtodemonstratetheextentofkyphosisandthemostlikelycause
isvertebralcollapse.


• Thelateralviewrevealshowerroneoustheperceptionofareductioninsizeofthechestmaybe,
as the increase in antero-posterior diameter is not readily appreciated on the frontal CXR.
(Fig5.4)




K2


AbNORmAliTiEs OF THE THORACiC CAgE ANd CHEsT WAll • 57


Figure 5.5
Frontal CXR of an adult male with metasatic prostatic carcinoma. Note the increased density of the ribs due
to diffuse sclerotic metastases.


Figure 5.6
Frontal CXR of an adult male with a primary adenocarcinoma of the lung (white arrow) and a lytic clavicle
metastasis (black arrow).




58 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


K2


Figure 5.7
Frontal CXR of a patient with multiple myeloma. Note the lytic lesion seen in the lateral right lower rib (horizontal white
arrow) in the left magnified view. in the right magnified view are a pathological fracture of the clavicle (black arrow),
endosteal scalloping due to lytic lesions in the ribs (vertical white arrows) and a lytic lesion in the scapula (diagonal
white arrow).


Cutaneous nodules
• CutaneousnodulesmaybeevidentonaCXRasanincreasedareaofdensity.


• Asthenoduleislikelytobeoutlinedbyadjacentair,itsmarginsaretypicallyverywelldefined.


• Thetruenatureoftheseopacitiesisindicatedbytheirpresenceoutsidethelimitsofthelungs.


• Ifthisisnotapparent,aninspectionofthepatient’schestwallshouldhelpexplaintheappear-
ances(Fig5.8).


Figure 5.8
Frontal CXR of a patient with neurofibromatosis. Numerous cutaneous neurofibromas are marked. Note that
those overlying the lungs appear like nodules in the lung but have very well defined margins. The presence of
numerous opacities not projected over the lungs confirms their cutaneous origin.




K2


AbNORmAliTiEs OF THE THORACiC CAgE ANd CHEsT WAll • 59


Soft tissue asymmetry
• AsthesofttissuesofthechestwallcontributesignificantlytotheabsorptionofX-raysduringthe
productionofthechestimage,achangeintheamountofsofttissuemayhaveamarkedeffect
ontheexposureoftheCXR.


• ThereductionorabsenceofsofttissueresultsinanincreaseinX-rayexposureoftheX-rayfilm,
creatingadarkerarea,e.g.mastectomy(Fig5.9),Poland’ssyndrome(congenitalabsenceofpec-
toralismuscle)andhemiplegiaorpoliocausingmusclewasting.


Figure 5.9
Frontal CXR of a patient who had had a left mastec-
tomy. Note the difference in transradiancy (darker on
the patient’s left) making the underlying lung appear
less vascular. both left and right lung are actually
normal. A further indicator of breast surgery is the
deformity in the axilla (black arrow).


• AnincreaseinsofttissueofthechestwallwillabsorbmoreX-rays,causinganincreaseinopaci-
ficationoftheX-rayfilm,e.g.tumour,haematoma,etc.


• SofttissuetumoursarisinginthelateralchestwallshouldbeapparentontheCXRthroughthe
resultantasymmetryinthicknessand/ordensity(Fig5.10,5.11).


Figure 5.10
Frontal CXR and axial CT image of a patient with lymphoma. Note the asymmetry in the chest wall due to a
large lymph node mass (black arrows), bilateral pleural effusions suggesting lung involvement and mediastinal
lymphadenopathy is also apparent (white arrows).




60 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


K2


Careshouldbetakentocomparethedensityoftherighthemithoraxwiththatoftheleft.


• Anincreaseinaxillarysofttissuemaybeduetolymphadenopathy(Fig5.12)andanincreasein
thesofttissuesofthelowerneckmayindicateagoitre(Fig5.13)orlymphadenopathy.


Figure 5.11
Frontal CXR of a
patient with a lipoma
of the chest wall. Note
the asymmetry of the
soft tissues and the
low density (black
arrow), indicating the
presence of fat. (Case
courtesy of Janet
dacey)


Figure 5.12
Frontal CXR of a young patient with
lymphoma. Note the long-term central venous
line for chemotherapy and bilateral axillary
adenopathy (white arrows).


Figure 5.13
Frontal CXR of a patient with carcinoma of the left lobe of thyroid. Note the deviation of the trachea to the right
(black arrow) and the increase in soft tissue opacity in the lower left neck.




K2


AbNORmAliTiEs OF THE THORACiC CAgE ANd CHEsT WAll • 61


Sickle cell disease
• Sicklecelldiseaseisahereditaryconditionthatresultsinabiochemicalabnormalityofhaemo-
globinresultinginthecrystallizationofhaemoglobinatlowoxygentensionandaresultingchange
intheshapeandflexibilityoftheredbloodcells.


• Theabnormal redbloodcellsareunable to traverse thecapillarybedoforgans,becomestuck
andthereforeembolizethebloodsupply.


• Sicklecelldiseasehaswidespreadimplicationscausingtissueischaemiaandinfarction.


• OnaCXR,infarctedareasoflungmaypresentasareasofatelectasis.Thechronicsequelofpul-
monaryhypertensionmaybeevidentthroughdilatedproximalpulmonaryarteries.


• Cardiomegalyisoftenfoundandinfarctsintheskeletonareevidentasareasofsclerosisandend
platedepressionofthevertebralbodies.


CXRsignsofsicklecelldisease(Fig5.14,5.15).


Figure 5.14
Frontal CXR of a patient with sickle cell disease. Note the cardiomegally and sclerotic ribs due to small bone
infarcts (horizontal black arrow). The magnified image demonstrates end plate depression (vertical black
arrows) again due to bone infarcts.


Figure 5.15
A second patient with sickle cell disease demonstrates cardiomegally and end plate depression (black arrows).
in addition to sclerotic ribs, there is focal sclerosis in the right humerous (magnified image) and band
atelectasis in the right lung due to pulmonary infarction.






K2


63


CHPATER 6


Lung tumours


CXR features of malignant tumours
Ill-defined/spiculated margins


• Apoorsignaspleurallybasedtumoursmayhaveill-definedmarginsandmalignanttumoursthat
primarilymetastasize via lymphatics andbloodvesselsmaynothave local invasion as amajor
component,andsubsequentlyhavewelldefinedmargins(Fig6.1).


Figure 6.1
Frontal CXR of a patient with primary adenocarcinoma of the lung. Note in the magnified view, the poorly
defined margins despite the size and intraparenchymal position of this tumour.


Rapid increase in size (Fig 6.2)


• Adoublingof volume in less than3months is unlikely tobe aneoplasmbutmore likely an
infectiveorinflammatoryprocess.


• Doublingtimesfrom3to18monthsarewithinthewindowformalignantlesions.




64 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


K2


Erosion of adjacent rib


• Erosionofanadjacent rib invariably indicatesmalignancy.Rarely, an infectiveprocesscausing
osteomyelitiscouldmimicthis(Fig6.3,6.4).


Figure 6.2
Frontal CXRs of an adult male taken 11 months apart. Note the rapid increase in size of the right lower lobe tumour.


Figure 6.3
Frontal CXR of a patient with primary squamous cell carcinoma of the lung. Note the preservation of the
diaphragmatic silhouette indicating that, although the increased opacity in the left lower zone has the
appearance of a pleural effusion, this is not the case. Note on the magnified view, the erosion of an adjacent
rib (horizontal black arrow) and a soft tissue mass extending outside the thoracic cavity (diagonal black
arrow).




K2


luNg TumOuRs • 65


Presence of hilar/mediastinal adenopathy (Fig 6.5)


• The presence of hilar adenopathy on the same side as the lesion, ormediastinal adenopathy,
increasesthelikelihoodofatumour,butequallymanyinfections,particularlyTBcanpresentin
thisfashion.


Figure 6.4
Frontal CXR of and adult male with primary adenocarcinoma of the right upper lobe. At first sight, the
increased opacity in the right upper zone may be taken to represent developing consolidation. However, the
presence of rib erosion (black arrow) reveals the underlying malignant pathology.


Figure 6.5
Two CXRs of the same patient with a bronchogenic carcinoma that is not readily seen on CXR. CXR at
presentation – right hand image – demonstrates hilar adenopathy (horizontal white arrows), paratracheal
adenopathy (diagonal white arrows), aorto-pulmonary window adenopathy (diagonal black arrow) and sub-
carinal adenopathy, the right hand margin of which is just visible (horizontal black arrow). The left image is
the CXR from a year previously, indicating that the diagnosis is new.




66 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


K2


Presence of a pleural effusion on the side of the lesion (Fig 6.6)


• Apoor sign as parapneumonic effusions are common and the solitary opacitymay be a local
pneumonia.


• However, in the contextofpossiblemalignancy, amalignantpleural effusionexcludes surgical
resectionasatherapeuticoption.


Figure 6.6
Frontal CXR of an adult female who has had a mastectomy and radiotherapy for a left breast carcinoma. she has
now developed a sarcoma within the chest wall secondary to the radiotherapy (horizontal white arrow) and a
reactive pleural effusion (vertical white arrow). Note the rib destruction to confirm the malignant nature of this
lesion (black arrow).


Evidence of lymphangitis carcinomatosa (Fig 6.7)


• Theradiologicfindingoflymphangitisinrelationtoasolitarypleuralopacityindicateslymphatic
involvementbythetumour.


Figure 6.7
Frontal CXR of a patient with bronchogenic carcinoma. Note the consolidative appearance in the left upper zone,
magnified image on the right and the corresponding section of the HRCT bottom right. The reticular pattern is due
to secondary pulmonary lobules outlined by thickened septa congested with fluid and tumour cells. A similar process
is beginning in the right lower zone left hand magnified image, where septal lines are evident (black arrow).




K2


luNg TumOuRs • 67


CXR features of benign tumours
Low density, high fat content


• Thepresenceoffatwithinalesionisaverystrongindicatorofabenignpathology,mostlikely
ahamartoma.


• LowdensitymaybedifficulttoappreciateonaplainCXRassurroundingsofttissuedensitywill
obscurethefatdensity.Plainfilmtomographymaydemonstratefatwithinalesion.


Calcification


• Calcificationinsmalllesions(<2cm)isagoodindicatorofabenignpathologybutaslesionsize
increases,thelikelihoodofmalignanttumourcontainingcalcium,increasesreducingtheuseful-
nessofcalcificationasasignofbenignity.Whenthecalcificationismarkedwitha“popcorn”like
appearancethediagnosisofahamartomaisusuallycorrect(Fig6.8).


Figure 6.8
Frontal CXR of a patient with a large hamartoma. Note the popcorn calcification seen on the magnified view
(black arrows) and the CT image (inset).


Slow or non-growing


• Ifasuspectlesionisseentobestaticingrowthoveraperiodof2years,abenignpathologycan
beassumed;thereforepreviousimaging,ifavailable,isinvaluable.


Metastases


• Metastatictumoursmaybesingleormultiple,butusuallyhavewelldefinedlobularmarginswith
theprimarymodeofgrowthdisplacingratherthaninfiltratingtheadjacentlung.


• Metastasesmay alsobe infiltrating innature, resulting in lesswell-definedmargins and,when
solitary,canbedifficulttodistinguishfromprimarylungcarcinoma.


• Inthepresenceoftwolesions,synchronousprimarytumoursarepossible,butaprimaryplusa
metastasisfromthatprimaryortwometastases,arefarmorelikely.


• Whentherearethreeormorelesions,atleasttwowillbemetastases,unlesstheappearancesare
duetoabenigncauseofmultiplenodulessuchasWegener’s,rheumatoidlung,sarcoidosisetc.
(Fig6.9).




68 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


K2


Bronchal carcinoma
Forthepurposesoftreatmentbronchogeniccarcinomacanbeconvenientlydividedintosmallcell
lungcancer(SCLC)andnon-smallcelllungcancer(NSCLC).


Non-small cell lung cancer


• TheNSCLCsareadenocarcinoma,squamouscellcarcinomaandlargecellcarcinoma.


• Whenproximal, these tumourmassesmay causeobstructionof the airways resulting indistal
collapseorconsolidation(seeGoldenSsignearlier)(Fig6.10).


Figure 6.9
Frontal CXR of an adult male with metastatic renal cell carcinoma. Note the multiple well defined “cannon ball”
metastases.




K2


luNg TumOuRs • 69


Figure 6.10
Frontal CXR of an adult male. The magnified view and CT image are marked to demonstrate a proximal soft
tissue mass (horizontal black arrow) and the well defined lateral margin of the upper lobe collapse distal to
the mass. Also note elevation of the left main bronchus and tenting of the left hemi-diaphragm (vertical black
arrow) in keeping with upper lobe volume loss. increased transradiancy of the left lower zone is due to
compensatory over-expansion of the left lower lobe and note the preservation of the left heart border
indicating the upper lobe collapse has not involved the lingula.


• Tumourslessthan1cmindiametermaynotbevisibleonCXR.


• Cavitationismostlikelytobefoundinsquamouscellcarcinoma.(Fig6.11)


Figure 6.11
Frontal and lateral CXRs of an adult smoker with cavitating quamous cell carcinoma in the right lower lobe
(black arrows).




70 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


K2


• Synchronousprimarylungcancers,althoughnotcommon,aredescribed.Thelessobviousofthe
two lesionsmaybemissedduetosatisfactionof search;whentheobserver stops lookingonce
theyfindanabnormality(Fig6.12).


Figure 6.12
Frontal CXR demonstrating synchronous primary tumours (white arrows); an adenocarcinoma in the right lung and a
squamous cell carcinoma in the left lung.


Small cell lung cancer


• SCLC tends to present withmassive lymhadenopathy and/or distantmetastases, CT brain is
routineinthestagingofthistumour.


• Theprimarytumourmaynotbeidentifieddespitelargevolumedisease.


• On CXR, the distinction betweenNSCLC and SCLC is not possible, but gross mediastinal
lymphadenopathy,outofproportiontothesizeoftheprimarytumour,shouldincreasesuspicion
ofaSCLC.




K2


luNg TumOuRs • 71


Non-mass like tumours
• Notalllungtumourspresentasnodulesormasses.


• Alveolarcellcarcinomaisanadenocarcinomathatmaypopulatetheairspacescausingtheappear-
anceofgroundglassopacityandsubsequentlyconsolidationonCXR.


• Thediagnosis shouldbe considered in thepresenceofmulti-focal consolidationor an areaof
consolidationthatfailstoresolveonappropriateantibiotictherapy(Fig6.13).


• Lymphomaandmetastaticadenocarcinomaaretheothermaintumoursthatmaypresentinthis
fashion.


Figure 6.13
Frontal CXR of a patient with alveolar cell carcinoma
demonstrates multifocal consolidation (black arrows)
with a more mass like appearance in the left apex
(white arrow).


Pleural tumours
• Tumoursarisingfromthepleuracharacteristicallyhaveeitherill-definedmargins,oronlydefined
marginsononeside.Thereasonforthisistheorientationoftheedgeofthemasswithrespect
totheX-raybeamduetothecontourofthepleura(Fig6.14).




72 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


K2


M U L DI G S I IM GI G


The solitary pulmonary nodule
• A soft-tissue, non-calcifi ed nodule visible on a CXR will be at least 1 cm in diameter; smaller


nodules are not readily seen.


• Numerous mimics of nodules, highlighted earlier under artefacts, should be excluded fi rst.


• The likelihood that such a nodule represents a neoplasm is dependent on the patient’s age,
smoking history, underlying lung disease and history of other neoplasms, but patient history will
not exclude a neoplasm.


• Ideally, the identifi cation of the same nodule on a previous CXR showing no change in size over
at least 18 months would confi rm a benign aetiology.


• Heavy calcifi cation in a solitary nodule indicates a benign aetiology.


• A watch and wait policy will attempt to identify signifi cant growth, i.e. a volume doubling time
of 3–18 months.


• A doubling in volume results in a 26% increase in diameter, i.e. a 1 cm nodule will measure
1.26 cm after doubling in volume, but this may take 18 months.


• In general, if facilities allow, solitary pulmonary nodules visible on a CXR and lacking any indica-
tion of a benign aetiology, should be imaged further with CT scanning.


Further imaging
• If an overlying rib obscures the suspected lesion, a lordotic view will project the ribs in a different


place.


• A lateral fi lm may be of benefi t.


• In the absence of CT, plain fi lm tomograms may identify benign type appearances, such as calci-
fi cation or fat.


Figure 6.14
Frontal CXR of an adult male with pleural metastases. Note the well-defi ned medial margins (white arrows) and the
angle the masses make with the internal chest wall (black arrows).


i , l ifi l i i l ill l i i ; ll
l il .


i i l , i li li , l l fi .


li li l l i i ’ ,
i i , l i l i i l , i i ill


l l .


ll , i ifi i l i i i i
l l fi i i l .


l ifi i i li l i i i i l .


i li ill i i i ifi ,i. . l li i
.


li i l l i i i i , i. . l ill
. li i l , i .


l,i ili i ll , li l l i i l l i i i
i i i l , l i i i .


l i i l i , l i i ill j i i i
l .


l lfil fi .


, l i fil i i i , l i
fi i .


.
l l l i l l . ll fi i l i ( i )


l i i l ll ( l ).




K2


73


CHAPTER 7


Pneumonias


Bacterial pneumonia
• Bacterialpneumoniaisthegrowthofpathogenicbacteriawithinthelung.


• Centred on the air-spaces, a pneumonia initially causes a vague increase in lung parenchymal
density (ground glass opacity).Then, as the air-spaces become filled with pus, consolidation
results.


• Cluestothepossibleinfectingorganismmaybegleanedfromthedistributionoftheconsolida-
tion,thepresenceofcavitationandevidenceofendobronchialspread.


Mycobacterial pneumonia


Pulmonary tuberculosis


• PulmonarytuberculosisiscausedbyM.tuberculosis.


• The radiologic appearances depend upon whether it is a primary infection, re-activation or
re-infection.


• PrimaryTBtypicallypresentswithconsolidation,mostcommonlyinthemidandupperzones.
(Fig7.1)




74 • THE WHO mAnuAl Of diAgnOsTiC imAging


K2


• Endobronchialspreadmaybetheonlyradiologicmanifestationandcanbeverysubtleindegree,
thereforecarefulscrutinyoftheCXRofaTBcontactshouldberoutinepractice(Fig7.2).


• LymphadenopathyisusuallyevidentonCXR(Fig7.3).


Figure 7.1
frontal CXR of an adult male with primary, smear positive, pulmonary TB. There is bilateral upper lobe consolidation
(black arrows) with the lobar distribution confirmed on the right by the demarcation of the minor fissure.




K2


PnEumOniAs • 75


Figure 7.2
frontal CXR of a young adult female who had been in contact with an index case of pulmonary TB. note the
asymmetry between the appearances of the upper zones. On the magnified image, the opacity in the right
apex is mainly nodular. HRCT through that area confirmed a “tree in bud” pattern found when small airways
are plugged and confirmed in this case to be due to TB.


Figure 7.3
frontal CXR of an adult female with tuberculosis. note the widened paratracheal stripe (horizontal black
arrow) and outside that the lateral margin of the superior mediastinal adenopathy (horizontal white arrow),
the anatomy giving rise to these lines are marked on the upper CT image. note also on the upper CT image
the peripheral enhancement and central necrosis characteristic of TB lymphadenopathy (diagonal black arrow).
This patient has an associated pericardial effusion (lower CT image) causing the loss of the normal concavity
seen in the left heart border at the site of the left atrial appendage (diagonal white arrow) and an overall
globular shape.




76 • THE WHO mAnuAl Of diAgnOsTiC imAging


K2


• The disease is usually self-limiting, but resolution takes 6–12months and residual scarring is
common(Fig7.4).


• Post-primaryTBresultsfromre-activationorlesscommonlyre-exposure.


• ThereisoverlapwithprimaryTBonCXR,buttheabsenceoflymphadenopathyandmorefre-
quentcavitationareusefulindicators(Fig7.5).


• HaematogenousspreadofTBmayleadtomiliaryTBpresentingwithdiffusenodulesthroughout
thelungs(Fig7.6).


Figure 7.4
frontal CXR of the same patient as above following treatment for TB. The consolidation has resolved, but residual
fibrotic scarring remains in both apices (white arrows).




K2


PnEumOniAs • 77


Figure 7.5
frontal CXR of an adult male with pulmonary TB. The upper image demonstrates a cavitating soft tissue
lesion in the right apex, but no lymphadenopathy. The lower image was taken following 6 months of
treatment. The lesion has almost completely resolved, but a residual cavity and adjacent scarring remain.


Figure 7.6
frontal CXRs of an adult male. On the right hand image there are small nodules spread throughout the lungs
all in the region of 2–3 mm in size. The patient was culture positive for pulmonary TB. note the left hand
image of a CXR taken 2 months earlier, when the patient was developing symptoms of pulmonary TB, but
there were no signs of this on the CXR.




78 • THE WHO mAnuAl Of diAgnOsTiC imAging


K2


Non-tuberculous mycobacteria (NTM)


• There are numerous NTMs that cause disease in humans; the commonest are listed in
table7.1


Table 7.1 Most common species of NTMs that cause pulmonary disease
in humans


Species of mycobacterium
M.avium-intracellulare
M.kansasii
M.xenopi
M.fortuitum
M.chelonae


• M.kansasiiandM.xenopiinfectionsareindistinguishablefrompulmonaryTB(Fig7.7).


Figure 7.7
frontal CXR and a plain tomogram of the chest of an adult male with M.kansasii infection in the right apex. note the
patchy parenchymal opacification and the thick walled (black arrow) cavitating lesions (white arrow) indistinguishable
from pulmonary TB. (images courtesy of Janet dacey)




K2


PnEumOniAs • 79


• M.fortuitum appears to prefer an acidic environment and has been associatedwith aspiration,
radiographicallypresentingwithlowerzoneconsolidation.


Pneumococcal pneumonia


• Pneumococcalpneumoniaduetoinfectiontendstogiverisetolobarorsegmentalconsolidation,
oftenwithanassociatedpleuraleffusion(Fig7.9).


• M.avium-intracellularemaybefound,butwhenpathologicalittendstoproducescatterednodu-
larityandconsolidation.Cavitationisalessfrequentfeatureandthereisoftenassociated“treein
budpattern”,butthisisnotreadilyappreciatedonCXR(Fig7.8).


Figure 7.8
frontal CXR of an adult female with culture confirmed M.avium-intracellulare infection. note the ill defined
nodularity in the mid zones (white arrows), which on the CT images are more evident and in places resolve
into a “tree in bud” appearance indicating endobronchial disease.




80 • THE WHO mAnuAl Of diAgnOsTiC imAging


K2


Figure 7.9
frontal CXR of an adult male with pneumonia confined to the anterior segment of the right upper lobe. note the
inferior demarcation by the minor fissure (white arrows).


Staphylococcal pneumonia


• Infectionby staphylococcus aureusgivingrise toconsolidationnotnecessarily restrictedto lobar
orsegmentalanatomy.


• Complicatedbyabscessformation,cavitation,empyemaandpneumothoraces.(Fig7.10)


Figure 7.10
frontal CXRs of an adult female with a staphylococcal pneumonia taken 1 month apart. note the cavitating consoli-
dation in the left mid zone (left image) resolving on treatment (right image).




K2


PnEumOniAs • 81


Figure 7.11
A pneumatocele in a patient who had had a staphylococcal pneumonia as a child. note the thin wall, the
entirety of which is visible (white arrows), unlike the wall of a bulla.


• A long-term sequel is a pneumatocele.The appearance is similar to that of a cavity, but thin
walledwithnoadjacentlungparenchymalopacitytosuggestactiveinflammation(Fig7.11).




82 • THE WHO mAnuAl Of diAgnOsTiC imAging


K2


Klebsiella pneumonia


• Klebsiella aeriginosa causes a similar pneumonia to staphylococcus, favours the upper lobes,
withadestructiveinflammation,bulgingoffissures,abscessformationandsubsequentcavitation
throughfibrousresolutionsimilartopulmonaryTB(Fig7.12).


Figure 7.12
frontal CXRs of an adult female taken 6 months apart. On the initial CXR (left) there is a large abscess within the
right upper lobe (black arrows vertical up) and bulging of the horizontal fissure (white arrow vertical up). On the
subsequent CXR (right) there remains a thick walled cavity (horizontal white arrow) and upward bowing of the minor
fissure (black arrow vertical down) indicating fibrosis.


Eosinophilic pneumonia


• Eosinophylicpneumoniadescribestheaccumulationofeosinophilrichmaterialintheair-spaces
resultinginconsolidation.


• Thecharacteristicfindingisofflittingconsolidation;theconsolidationcomesandgoesovertime
indifferentareasofthelung(Fig7.13).


Figure 7.13
A sequence of 4 CXRs of a patient with
eosinophilic pneumonia taken over a period of
18 months. note how the areas of consolida-
tion vary in site (black arrows). The flitting
consolidation is typical of eosinophilic
pneumonia.




K2


PnEumOniAs • 83


Organizing pneumonia


• Organizingpneumoniaisanon-infectiveentity.Inflammatorytissuegrowingintothedistalair
spacesandtheinterstitiumcausesconsolidation(Fig7.14).


• TheassociationsoforganizingpneumoniaaregiveninTable7.2.


• Usually,peripheralmaybemultifocaland/orflittinginnature.


• Thedistinctionbetweenorganizingpneumoniaandan infectivepneumoniacannot readilybe
madeonaplainCXR(orCTscanning)andthediagnosisisusuallydelayedasaresult.


Figure 7.14
frontal CXR of a patient with cryptogenic
organizing pneumonia. The diagnosis was
finally made on open lung biopsy following
the failure of numerous courses of antibiotics.
note the patchy consolidation (white arrows).


Table 7.2 Associations of organizing pneumonia


infECTiOn
Bacterial e.g. streptococcus pneumonia, legionella pneumophila
Viral e.g. Adenovirus, CmV, influenza, Parainfluenza, HiV


dRugs
Antibiotics e.g. amphotericin B, cephalosporins, minocycline
Others e.g. sulfasalazine, bleomycin, amiodarone


COnnECTiVE TissuE disORdERs
e.g. systemic lupus erythematosus, rheumatoid arthritis, sjogren syndrome


immunOlOgiCAl disORdERs
e.g. common variable immunodeficiency syndrome, essential mixed
cryoglobulinaemia


ORgAn TRAnsPlAnTATiOn
e.g. bone marrow, lung, renal


misCEllAnEOus
e.g. inflammatory bowel disease, primary biliary cirrhosis, polyarteritis nodosa,
haematological malignancies, radiotherapy.




84 • THE WHO mAnuAl Of diAgnOsTiC imAging


K2


The immunocompromised patient


• Intheimmunocompromisedpatient,thepatternsofpneumoniaalreadydescribed,arelesslikely
to assist in adiagnosis.Furthermore,normallynon-pathogenicorganismsmaybecomepatho-
genic,increasingtherangeofpossibleinfectingagents;inparticular,pneumocystisjirovecipneu-
monia(previouslyknownaspneumocystiscariniipneumonia)(Fig7.15)andfungal infections
(Fig7.16).


Figure 7.15
frontal CXR of an immunocompromised patient with pneumocystis jiroveci pneumonia. note in the magnified
image a ground glass opacity with some nodular elements tending towards confluence/consolidation. The
appearances are non-specific.


Figure 7.16
frontal CXR of an immunocompromised adult patient with signs and symptoms of infection. note the diffuse
nodularity (black arrow) as a result of infection with histoplasmosis. (images courtesy of Janet dacey).




L1


85


CHAPTER 8


Chronic airways disease


Asthma
Most asthmatics have a normal CXR, but a few have large volume lungs.


Asthmatics are prone to spontaneous pneumothorax, pneumomediastinum (Fig 8.1) and mucous
plugging which may cause lung opacification and collapse (Fig 8.2).


Figure 8.1
Frontal CXR of a patient with asthma who has developed a spontaneous pneumomediastinum. Note the air
outlining the upper mediastinal structures and extending into the root of the neck (white arrows).




86 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


L1


Chronic bronchitis
• Chronic bronchitis is a disease primarily associated with smoking and, when severe, may be


evident on a CXR through the associated bronchial wall thickening, causing the bronchovascular
markings to be more obvious and perceived further from the hila (Fig 8.3).


Figure 8.2
Two sequential frontal CXRs of a patient with asthma. Right image demonstrates complete opacification of the right
hemithorax, but also mediastinal shift to the right (white arrow) indicating the cause is collapse of the lung and not a
large pleural effusion, which would tend to shift the mediastinum the other way. The cause is a plug of mucous in the
right main bronchus (black arrow) and following removal at bronchoscopy, there is re-expansion of the lung (left
image) return of the mediastinum to a more central position (white arrow) and just a small residual area of consolida-
tion (diagonal white arrow).




CHRONiC AiRWAys disEAsE • 87


L1


• Normally, the bronchi can be seen to segmental level, more peripherally, only the vessels are
visible.


• In chronic bronchitis, the thickening of the bronchial wall results in extra lines adjacent to the
vessels that increases the number of visible lung markings.


• As a disease of smokers, emphysema usually coexists with the chronic bronchitis and has the
opposite effect on the appearance of the lungs on CXR.


Figure 8.3
Frontal CXR of an adult male with a long history of cigarette smoking. Note the more obvious bronchovascu-
lar markings, large volume lungs, but lacking flattening of the hemidiaphragms or obvious signs of
emphysema.




88 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


L1


Emphysema
Emphysema is divided into 4 overlapping presentations, centrilobular, bullous, paraseptal, and
panacinar.


• Pathologically, there is destruction of lung tissue causing loss of the area over which gas exchange
occurs and loss of the normal supporting structure of the lung.


• Destruction of lung tissue results in increased transradiancy, or a darker lung. In the area of
emphysema, the vessels may be identifiably smaller and less numerous.


• The trapping of air has a space occupying effect in the thorax, which therefore holds a greater
overall volume causing flattening of the diaphragms and expansion of the chest dimensions.
Normal volume lungs extend over 6 anterior ribs. More than this suggests over-expansion (Fig
8.4), but flattening of the hemi-diaphragms should co-exist with pathological lung
over-expansion.




CHRONiC AiRWAys disEAsE • 89


L1


Figure 8.4
Frontal CXR of an adult male with a long history of cigarette smoking. Note the over-expanded lungs (8
anterior ribs above the hemi-diaphragm) due to emphysema. The flattening of the left hemi-diaphragm as
judged by measuring the maximum perpendicular distance from a line drawn between the medial and lateral
extents of the diaphragm to the diaphragmatic surface (appropriate line marked for left hemi-diaphragm). The
measurement should be >1.5 cm.


Centrilobular emphysema


• Centrilobular is the commonest form of emphysema and is a condition found in smokers, typi-
cally affecting the upper and mid zones.


• Centrilobular emphysema can be difficult to appreciate on a CXR as the lung destruction is at
the centrilobular level and only quite extensive disease will result in sufficient lung destruction to
be appreciated on CXR through a reduction in lung markings and over-expansion (Fig 8.5).




90 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


L1


Figure 8.5
Frontal CXR of an adult male patient with a long history of cigarette smoking. Note the reduced lung markings in the
upper zones due to centrilobular emphysema. High-resolution CT scanning confirmed this.


Bullous emphysema


• Bullous emphysema is characterized by bullae, which cause areas of absence or paucity of lung
markings. Only a proportion of the wall of the bulla is usually visible creating thin curvilinear
lines (see “pattern recognition”) (Fig 8.6).


Figure 8.6
Frontal CXR of a patient with bullous emphysema. Note
the curvilinear lines (arrows) formed by the walls of the
bullae, but the entire wall is not visible.


Para-septal emphysema


• Para-septal emphysema is defined by distribution rather than by the type of lung destruction. The
emphysematous destruction occurs in the subpleural regions and adjacent to the fissures.


• The appearances are those of both bullous and centrilobular emphysema and, as a pattern of
disease para-septal emphysema, is not readily appreciated on CXR.




CHRONiC AiRWAys disEAsE • 91


L1


Panacinar emphysema


• On CXR, the distinction between panacinar and centrilobular emphysema is not possible, but
the distribution may be revealing.


• Alpha-1 anti-trypsin deficiency, a relatively rare form of emphysema, causes panacinar emphysema
and typically affects the lower zones of the lung rather than the upper/mid zone distribution of
smoking related centrilobular emphysema (Fig 8.7).


Figure 8.7
Frontal CXR of an adult male with alpha-1 antitrypsin deficiency. Note the reduced number and size of vessels
in the lower zones compared to the upper and mid zones and over-expansion of the lungs with flattening of
the hemidiaphragms. The inset HRCT images are from the mid zone (top image) and the lung base (bottom
image) and display the difference in severity of the emphysematous destruction of the lung tissue.


Bronchiectasis
• Bronchiectasis is defined by the presence of dilated bronchi with thickened walls.


• CXR is insensitive for the detection of bronchiectasis with only severe disease being identified
with any certainty.


• Bronchiectasis is descriptively divided into 3 types; cylindrical, varicose and cystic.


Cylindrical bronchiectasis


• Cylindrical bronchiectasis describes uniformly dilated, non-tapering airways.


• CXR reveals tramlines adjacent to lung vessels and rings when the dilated bronchi are seen end
on (Fig 8.8).




92 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


L1


Figure 8.8
Frontal CXR of a patient with cylindrical bronchiectasis, on the magnified image are ring shadows (white arrows) and
tram lines (black arrows), representing dilated bronchi end on and lengthways respectively.


Figure 8.9
left image is a frontal CXR of an asthmatic patient with ABPA. Note the patchy consolidation, bronchial wall
thickening and bronchial dilatation (white arrows). The right image is an HRCT of the same patient demonstrating
the bronchiectasis. The distribution is typically central in the mid and upper zones.


Varicose bronchiectasis


• Varicose bronchiectasis describes a non-uniform dilatation of the bronchi forming multiple
sequential bead-like dilatations which when viewed on a CXR, will appear cystic but in the plane
of the CXR will have an undulating appearance.


• Varicose bronchiectasis is typically associated with allergic bronchopulmonary aspergillosis (ABPA)
with a central mid and upper zone distribution (Fig 8.9).




CHRONiC AiRWAys disEAsE • 93


L1


Cystic bronchiectasis


• Cystic bronchiectasis describes non-uniform dilatation of airways between which there are less
dilated or even normal calibre airways (Fig 8.10).


• CXR reveals ring shadows that may contain fluid giving rise to air-fluid levels.


Figure 8.10
Frontal and lateral CXR of a patient with cyctic bronchiectasis secondary to a childhood infection and confined
to the right middle lobe. Note the “cysts” with thin walls (black arrows). The “cysts are either focal dilatation
of the bronchi or saccular out-pouchings from the bronchi.




94 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


L1


Figure 8.11
Frontal CXR of a young adult female with cystic fibrosis. Note the predominantly central bronchiectasis with ring
shadows clearly evident (white arrows). The presence of a portocath (black arrow) indicates this patient is on long term
intravenous medication like many cystic fibrosis patients are.


• Cystic fibrosis is a congenital condition resulting in impaired ciliary motor activity and thickened
secretions. In the lungs this results in bronchiectasis in a mid and upper zone distribution classi-
cally and the CXR is quite characteristic (Fig 8.11).




L1


95


CHAPTER 9


Diffuse lung disease


Fibrosis
• TheCXRisaninsensitiveinvestigationfordetectingpulmonaryfibrosis.


• TheadventofHRCThasdemonstratedmildtomoderatedegreesoffibrosisthatarenotdetected
onCXR.


• Whenfibrosis is apparentonCXRthecardinal feature is reticulation, afinenetworkof lines,
correspondingtofibrousthickeningofthelunginterstitiumsuchthatitbecomesvisibleonCXR
(Fig9.1).


Figure 9.1
Frontal CXR of a patient with idiopathic pulmonary fibrosis. The magnified area demonstrates the interlacing
network of lines described as reticulation, which represent the visible pathologically thickened interstitium, in
this case due to fibrosis.


• Tomakeadiagnosisoffibrosistheotherconditionsthatthickentheinterstitiumsuchasinter-
stitial oedema inheart failure, lymphangitis carcinomatosa and alveolarproteinosis, shouldbe
excludedorotherevidenceoffibrosisshouldbepresent.


• Thepresenceofvolumelossintheregionofreticulation(Fig9.2)and/orhoneycombdestruction
supportsadiagnosisoffibrosis.


• Honeycombdestructionof the lung is primarily a feature of idiopathic pulmonaryfibrosis, is
characteristicallyperipheralandbasalinsiteandmaybeseenonCXRifsevere(Fig9.3).




96 • THE WHO mAnuAl OF diAgnOsTiC imAging


L1


• Manypatientswithpulmonaryfibrosisarealsosmokersandthepresenceofco-existentemphy-
semaintheupperzonesmaymasksignificantlowerzonevolumelossduetofibrosis(Fig9.4).


Figure 9.2
Frontal CXR of an adult male with diffuse lung fibrosis. As a result there is reduced lung expansion evident on this full
inspiratory film.


Figure 9.3
Frontal CXR of a patient with idiopathic pulmonary fibrosis. note the “holes” in the periphery in the
magnified section and the increased volume of the lungs, not expected in fibrotic lung, due to co-existent
emphysema. The bottom right inset is from the high-resolution CT scan of the same patient demonstrating
the peripheral/sub-pleural honeycomb destruction.




diFFusE lung disEAsE • 97


L1


Figure 9.4
Friontal CXR of a patient with idiopathic pulmonary fibrosis and co-existent emphyhsema. note the paucity of
lung markings in the upper zones (white arrows) in conjunction with normal volume lungs and widespread
reticulation extending from the lung bases.


Lymphangitis carcinomatosa
• Lymphangitis carcinomatosa describes the infiltrationof the lymphatic vessels by tumour (Fig
9.5).


• Theresultisinterstitialthickeningcausingreticulation.


• Cluestodifferentiatethiscauseofreticulationfromfibrosisaretheabsenceofvolumeloss,the
asymmetricalnature,prominentseptallines,whicharemuchlessofafeatureinfibrosis,andthe
identificationofaprimarytumourormediastinallymphadenopathy.


Figure 9.5
Frontal CXR of an adult female. note in the magnified view on the left, there are prominent septal lines (black
arrows) and on the right, note the reticulation (see inset HRCT). This patient has a left mid zone carcinoma of
the bronchus with associated lymphangitis carcinomatosis. The cause for the right basal septal lines is
uncertain. in the absence of obvious reticulation and the history of cardiac failure, note an enlarged heart and
valve replacement, left heart failure is the more likely aetiology.


LAM
• Lymphangioleiomyomatosisishistologicallyidenticaltotuberoussclerosisinthelungs.


• Adiseasealmostexclusivetowomen,thisdiagnosisshouldnotbeconsideredinmalepatients.


• ThecharacteristiclesionisbestappreciatedonHRCTwherebytherearenumerousairfilledcysts
distributedthroughoutthelungswithnormallungparenchymainterspersed.




98 • THE WHO mAnuAl OF diAgnOsTiC imAging


L1


• OnCXR,thewallsofthesecystsgivetheappearanceofreticulation.Acluetothetruenatureis
in thepreservationof lungvolumesandclarityof themediastinal contours in thepresenceof
whatappearstobediffusepulmonaryfibrosis(Fig9.6).


Figure 9.6
Frontal CXR of a patient with lAm. Again note the “holes” on the magnified view as for lCH but the
absence of nodules is difficult to appreciate with the projection of so many overlapping cyst walls. The
appearances could easily be mistaken for reticulation due to interstitial pathology but changes to this extent
would involve and obscure the silhouette of the heart border and diaphragm and these are clearly intact
(arrows).


LCH
• Langerhan’scellhistiocytosis is themaindifferentialdiagnosisalongwithLAMfordiffuseair-
filledcystsinthelung.


• The characterization of these cysts and distinguishing factors are only readily appreciated on
HRCT.


• ThenumerouscystsgiveareticulationtypepatternonCXRasforLAM,butnodulesthatwill
subsequentlydevelopintocystsmaybeseen.


• LCHisa smokingrelateddiseaseandthedistributionofdisease tendstobe intheupperand
midzoneswithsparingofthelungbases(LCH)(Figure9.7).




diFFusE lung disEAsE • 99


L1


Figure 9.7
Frontal CXR of a patient with lCH. note in the magnified region the combination of “holes” and nodules.
The CT image (bottom right) demonstrates the irregular shape of the cysts giving rise to the CXR appearances
and confirms the presence of nodules.


• InseverediseasethedistinctionbetweenLAMandLCHmaynotbepossibleradiologically,even
onHRCT.


Pulmonary sarcoid
• Sarcoidosisisasystemicgranulomatouscondition.


• Thespectrumoffeaturesfoundinthelungenablesarcoidtomimictheradiologyofmanyother
pulmonarypathologies.


• The characteristic presentation is of bilateral, symmetrical hilar adenopathy with or without
mediastinaladenopathyandthemaindifferentialforthisappearanceislymphoma(Fig9.8).


Figure 9.8
Frontal CXR of a patient with sarcoidosis. note the
bilateral hilar adenopathy (white arrows) and the likely
paratracheal adenopathy. Furthermore, the azygo-
oesophageal line is obscured (black arrow) suggesting
subcarinal lymphadenopathy.




100 • THE WHO mAnuAl OF diAgnOsTiC imAging


L1


• Lungparenchymalinvolvementmaypresentwithfibrosisevidentasreticulation,typicallyinthe
upperandmidzones(Fig9.9).


Figure 9.9
Frontal CXR of a patient with long standing sarcoidosis. The left image shows mid, and to a lesser extent,
upper zone patchy opacity and peripheral nodularity (white arrows). CT imaging demonstrates the ground
glass opacity caused by fibrosis. note the dilated airways.


• SarcoidosismaymanifestasanodularpatternsimilarinappearancetomiliaryTB(Fig9.10)or
consolidation(Fig9.11),whichtendstobeperipheralandpatchy.


Figure 9.10
Frontal CXR of a patient with sarcoidosis presenting with multiple nodules, see magnified image. The appearance is
difficult to distinguish from miliary TB radiolgically, but clinically, patients with TB are very unwell whereas those with
sarcoid may have no symptoms.




diFFusE lung disEAsE • 101


L1


Figure 9.11
Frontal CXR and HRCT image of a patient with sarcoidosis. note the consolidation (white arrow) and marked
mediastinal and hilar lymphadenopathy (black arrows).


Figure 9.12
Frontal CXR of a patient with sarcoidosis. note the area of consolidation due to air space sarcoid (black arrow)
and the numerous nodules (white arrows) that mimic metastases as they are larger than the nodules usually
associated with sarcoid. The nodules also look like metastases on the CT images but note the lining up of the
nodules along the left major fissure in the bottom CT image giving a clue to their true nature.




102 • THE WHO mAnuAl OF diAgnOsTiC imAging


L1


• In general, if the patient is clinicallymuch better than their radiologywould suggest, sarcoid
shouldbeconsideredasapossiblediagnosis.


Hypersensitivity pneumonitis (HP)
• Hypersensitivitypneumonitis,previouslyknownasextrinsicallergicalveolitis,resultsfromtype
2andtype4hypersensitivityreactionstoinhaledorganicallergens.


• HPcanbedividedintothreetypesbasedonexposure,symptomatologyandradiology.


Acute HP


• AcuteHPpresentsasatransientvirallikeillnessandrarelyresultsinpresentationtoadoctor.


• OnCXRinacuteHPtheremaybeill-definedareasofgroundglassopacity(Fig9.13).


Figure 9.13
A frontal CXR of an adult female diagnosed with acute hypersensitivity pneumonitis. note the patchy ground grass
opacity.


Sub-acute HP


• Sub-acuteHPresultsfromrepeatedexposuretotheallergenandpresentswithfevers,difficulty
inbreathingand“squeaks”onexamination.


• TheCXR again primarily shows ground glass opacity and possibly ill-defined nodularity (Fig
9.14).




diFFusE lung disEAsE • 103


L1


Figure 9.14
Frontal CXR of an adult female with sub-acute hypersensitivity pneumonitis. note in the magnified view there
are numerous small soft tissue nodules seen in the lung.


Chronic HP


• ChronicHPresultsfromcontinuedexposuretotheallergensuchthattheinflamedlungbecomes
permanentlydamagedandfibrotic.


• ThefibrosistendstohaveanupperandmidzonepredominanceandisevidentonCXRasfibrous
bandsand/orreticulationintheupperandmidzoneswithelevationofthehilarindicatingupper
lobevolumeloss(Fig9.15).


Figure 9.15
Frontal CXR of an adult male with chronic hypersensitivity pneumonitis. The inset images demonstrate the
HRCT appearances in the upper mid and lower zones. note on the CXR the reticular pattern primarily in the
mid and upper zones and elevation of the hila particularly on the left.






L1


105


CHAPTER 10


Pleural disease


• Thepleuraisathinmembranethatmaybelikenedtoasealed“bag”thatiswrappedaroundthe
lungformingtwolayers,oneagainstthelung,thevisceralpleura,andoneagainsttheinsideof
thechestwall,theparietalpleura.


• Eachlunghasitsownpleural“bag”.


• Theparietalpleuraisfixedtotheinnerchestwallandthepotentialspacethatliesbetweenthe
twolayersofpleura,theinsideofthebag,isemptyexceptforasmallamountoffluid.


• Thesurfacetensionofthefluidisstickyenoughto“glue”thetwolayersofpleuratogethersuch
thatasthechestwallexpandsthelungwillexpandwithit.


• Atthesametimethelayersofpleuraallowthelungandchestwallto“slideagainstoneanother”
suchthatinfillingthethoraciccavitythelungdoesnothavetomatchthemovementofthechest
wall.


• Oninspirationthedepressionofthediaphragmshasasignificantimpactontheincreaseintho-
raciccapacityandinfillingthisspacethelungselongateaswellasexpandlaterallythuscreating
ashearingmovementrelativetothechestwall.


• Thisisfacilitatedbythetwolayerpleuraldesignbutasaresultthereisapotentialspacebetween
thepleuralsurfacesandaccumulationofairorfluidinthisspacewillaffectitsfunction.


• Diseasesthatcausealossoftheabilityofthepleuralsurfacestoslideoveroneanotherwillhave
animpactonlungexpansionandmaypresentwithchestwallpainrelatedtobreathing.


Pneumothorax
• Pneumothoraxdescribesthepresenceofairinthepleuralspace.


• Therearetwomainsourcesforthisair,thelungorabreachofthechestwall,e.g.traumaorsur-
gicalprocedure.


• Intheabsenceofachestwallbreachthecausewillbelungpathology,whichatthesimplestlevel
maybea surfacebleb,“bubble”, thathasburst,acauseof spontaneouspneumothoraxusually
foundintallyoungmen.Alternativecausesincludeinfections,particularlydestructiveabscesses,
malignancyorinternaltraumaticdamagetothemajorairways(Fig10.1).




106 • THE WHO mAnuAl Of diAgnOsTiC imAging


L1


• Airinthepleuralspacebreaksthewatersealthatsticksthetwolayersofpleuratogetherallowing
thelungtocollapsethroughitsinherentelasticity.


• ApneumothoraxisevidentonaCXRwherethereisanabsenceoflungmarkingsandadefined
edgetothelung(Fig10.2).


Figure 10.1
spontaneous pneumothorax in a young tall male patient who presented with sudden onset of left sided chest
pain. note the subtle lung edge visible in the magnified view (white arrows) and the blunting of the left
costophrenic angle where the fluid normally found in the pleural space has accumulated at the base (black
arrow).


Figure 10.2
An adult male patient with a right-sided pneumothorax following percutaneous biopsy of an upper lobe
tumour. note the lung edge (white arrows) beyond which there are no lung markings. note also the junction
between the right middle and lower lobes, the major fissure (diagonal black arrow).




PlEuRAl disEAsE • 107


L1


• Thesizeofthepneumothoraxwillhaveanimpactonhowlongittakestospontaneouslyresolve
aprocessthatmaybeacceleratedbyhighdoseoxygentherapy.


• Aspirationordrainagewithanunderwatersealwilldramaticallyspeeduptheresolutionofthe
pneumothorax.


• Ifair isenteringthepleuralspacebut,duetoanaturalone-wayvalve, isunabletoescape,the
volumeofairwillcontinuetorisecausinganincreaseinvolumeofthepleuralspacepushingthe
mediastinumtotheoppositeside.


• Theresultistermedatensionpneumothoraxandisalifethreateningcondition.


• OnCXR,thepresenceofmediastinalshiftawayfromalargepneumothoraxandflattening,even
inversion, of the hemidiaphragm beneath the pneumothorax are signs of tension and urgent
drainageisrequired(Fig10.3).


Figure 10.3
frontal CXR of an adult patient with a tension pneumotho-
rax. note the comparison of the hemidiaphragms (black
arrows), the right hemidiaphragm is flattened compared to
the left, and the mediastinal shift away from the pneumotho-
rax (white arrows).


• Softtissueemphysema,thedevelopmentofairinthesofttissues,maycomplicateapneumothorax
andcanbefoundinthemediastinum,chestwallandneck.


• SofttissueemphysemaisreadilyapparentonCXRaslucentbubblesorlinesinnormallyrelatively
opaquesofttissues(Fig10.4).


Figure 10.4
frontal CXR of an adult with a tethered pneumothorax.
There is a chest drain in-situ (white arrow) and soft tissue
emphysema due to air leak around the drain (black
arrows).




108 • THE WHO mAnuAl Of diAgnOsTiC imAging


L1


• OnaCXRtakenwiththepatientinasemi-erectorsupineposition,apneumothoraxmayreside
intheanteriorpartofthehemithorax.


• AnanteriorpneumothoraxmaycausenovisiblelungedgeasthisisnotintheplaneoftheX-ray
beambutacrossit.


• Cluestoananteriorpneumothoraxareverywelldefinedmediastinalanddiaphragmaticsilhou-
ettes,where airhas replaced lung adjacent to themediastinumanddiaphragm (Fig10.5) and
reducedopacityoverlyingthediaphragmwheretheairhasreplacedthelungeitherinfrontofor
behindthediaphragmandenlargedthatspace.


Figure 10.5
frontal CXR of a post-thoracotomy patient who
has developed bilateral pneumothoraces. note the
clarity of the mediastinal contours and the
diaphragms (white arrows).


Figure 10.6
AP CXR taken on an intensive care ward appears to demonstrate a pneumothorax. An apparent lung edge is
seen (large black arrows) but on closer inspection there are lung markings beyond the supposed lung edge
(small black arrows). The margin of the scapula is also marked (white arrows).


• AlateralCXRtakenwiththepatientsupineandtheX-raybeamhorizontallyalignedmayidentify
thelungedgeinasuspectedanteriorpneumothorax.


• Askinfoldmaymimictheappearanceofalungedgebutnottheabsenceoflungmarkings(Fig
10.6).




PlEuRAl disEAsE • 109


L1


• ThisappearanceismorelikelytooccuronaportableCXRasthefilmcassetteisplacedbehind
thepatientandinleaningbackagainstthefilmaskinfoldmaybecreatedespeciallyifthepatient
hasrecentlylostweight.


Effusion
• Thepleuralspacenormallyhasasmallamountoffluidwithinit;thisisevidentintheblunting
ofthecostophrenicangleonthesideofapneumothoraxwherethisfluidhascollectedatthebase
(Fig10.1).


• Thephysiologicalpleuralfluidisconstantlybeingreplenishedbythecombinationofaccumula-
tionandabsorption.Accumulationinexcessofabsorptionresultsinapleuraleffusionandmay
thereforebecausedbyincreasingaccumulation,decreasedabsorptionorboth.


Table 10.1 Causes of pleural effusions


Intrathoracic
left heart failure
infection
neoplasm
Pulmonary embolus, infarction
Collagen vascular disease
Trauma


Extrathoracic
Hepatic failure
nephritic syndrome
meig’s syndrome (ovarian carcinoma)
subphrenic abcess
Panceatitis


Simple pleural effusion


• On an erectCXR, thefluidnormally accumulates at the bases due to gravitywith the upper
margindefinedbyameniscus(Fig10.7).


Figure 10.7
frontal CXR of a patient with a simple
pleural effusion. note the curved margin
of the meniscus (black arrows) but also
the increased opacity in the right lower
zone as the effusion also lies in front of
and behind the lung up to the level
marked by the faint line. There is also
fluid tracking into the major fissure (white
arrow).




110 • THE WHO mAnuAl Of diAgnOsTiC imAging


L1


• Inthesupineposition,asimplepleuraleffusionwillaccumulateposteriorlyinthechestandthe
abovedescribedmeniscaleffectisnotseen.


• Thereisanoverallincreaseinshadowingofthehemithorax,whichcanbeeasilyoverlooked.


• Iftheeffusionislargeenough,thereisapparentthickeningofthepleuraattheedgesduetothe
displacementoflungfromthechestwallbythefluid(Fig10.8).


Figure 10.8
supine CXR of an adult patient demonstrating a pleural effusion. note the rim of opacity surrounding the lung (white
arrows) due to fluid lying posterior and lateral where it separates the lungs from the chest wall.


• Whenthepatientissemi-erect,thefluidwillcollectpreferentiallyintheposteriorcostophrenic
recessandposteriorpleuralspace.


• Theresultisavagueincreaseinopacityinthelowerzoneswithpreservationofthediaphragmatic
silhouette,nomeniscusandevenanormalcostophrenicangle.Lobarcollapsedoesnothavethe
samedependenceonpatientposition(Fig10.9).




PlEuRAl disEAsE • 111


L1


Figure 10.9
semi-erect CXR of an adult in an intensive care unit. The patient has a large right pleural effusion causing
increased opacity of the right lower zone with fluid tracking into the minor fissure but preserving the
diaphragmatic (black arrows vertical up) and right heart border (black arrow horizontal) silhouettes due to the
posterior position of the fluid. note also on this CXR the loss of the left diaphragmatic silhouette (black
arrows vertical down) due to left lower lobe collapse; the left hilum is depressed (white arrow), the left main
bronchus is more vertical (black arrow diagonally down) and the right heart border overlies the spine (black
arrow horizontal) all signs which are indicating left lower lobe volume loss.


Subpulmonic pleural effusion


• Sometimespleuralfluidcollectsbeneaththelungwithlittleornocomponentextendinglateral
tothelung.


• Itcanbedifficulttoidentifyonanerectchest;thediaphragmoftenappearstobehighwiththe
domepeakingmorelaterallythanusual(Fig10.10).


• Typicallysubpulmoniceffusionsaresimpleinnatureandthereforethefluidisfreeflowingand
becomesapparentwhenthepatientisX-rayedinthesupineposition.




112 • THE WHO mAnuAl Of diAgnOsTiC imAging


L1


Figure 10.10
subpulmonic pleural effusion. left image – erect CXR demonstrates an apparently raised left hemi-diaphragm
(white arrow). note the diaphragm is peaking more laterally than usual. The right image is a supine CXR of the
same patient. The subpulmonic fluid has redistributed in the posterior pleural space causing a vague increase in
opacity, obscuring the left hemidiaphragmatic silhouette (black arrow) but preserving the left heart border as this
lies anteriorly (white arrow).


Complex pleural effusion


• Whenthecontouroftheeffusionisnotmeniscalasdescribedabovebutstraightorconvex,this
impliesthattheeffusioniscomplexinnaturecontainingviscousfluidand/orseptations.


• Complexeffusionsdonotnecessarilyoccupythedependentspacesandmaythereforeoccurin
isolationanywhereinthepleuralspace.


• A complex pleural collection raises the possibility of an empyema or haematoma but chronic
simpleeffusionscanbecomecomplexwithoutasuperveninginfectionandasimplepleuraleffu-
sioninacomplexpleuralspacemaymimictheseappearancesi.e.afterprevioussurgicalinterven-
tionorinfection(Fig10.11).


Figure 10.11
left image: erect frontal CXR of a patient with a complex pleural effusion. fluid aspirated was sterile. note
increased opacity but no meniscal appearance, a convex superior margin (white arrow) and relative preserva-
tion of the lateral subpleural region (horizontal black arrow) and left heart border (diagonal black arrow).
Right image: lateral CXR demonstrates posterior loculated fluid collection with a convex anterior margin
(white arrow) distinct from a normally positioned major fissure (black arrow).




PlEuRAl disEAsE • 113


L1


Empyema
• Anempyemaisaninfectioninthepleuralspace.Thefluidmayvaryfromturbidtothickpus
andcanbeverydifficulttodrain.


• OnCXRanempyemapresentsasacomplexpleuralcollection.


• Fibrousbandsmaycreateloculesandthethickerfluid/pusmaynotbeasmobileasthefluidof
asimplepleuraleffusion,thereforefailingtocollectinthedependentareas(Fig10.12).


Figure 10.12
frontal CXR of an adult with a right sided empyema. note the pleural based opacity with a vertical (white
arrows) rather than meniscal contour indicating a complex collection in this case including pockets of air
(black arrows).




114 • THE WHO mAnuAl Of diAgnOsTiC imAging


L1


• Thepresenceofpleuralopacitythatfailstoconformtothemeniscalappearancecharacteristicof
a simple pleural effusion should alert the reader to the possibility of an empyema, or pleural
tumour.


• Extension of an empyema outside the chestwallmaymimic an invasive soft tissuemass (Fig
10.13).


Figure 10.13
frontal CXR of an adult male patient with TB empyema extruding through the chest wall. The magnified
image demonstrates the increase in soft tissue of the chest wall (white arrows) and the convex upper margin
of the empyema. The CT inset demonstrates the loculated nature of the collection.


• Simplepercutaneousdrainageshouldbeattemptedpriortosurgicaldrainage.


• ResidualpleuralthickeningisacommonsequelofempyemaandabaselineCXRonresolution
ofsymptomswillhelpinterpretsubsequentCXRsshouldfurtherpleuralproblemsarise.


Haemothorax
• Ahaemothorax is thepresence of blood in thepleural space,which, as it becomesorganized,
behavesmorelikeanempyemathanasimplepleuraleffusionwithundulatingcontoursonCXR
duetoloculationandaccumulationinnon-dependentareas.


• Thepatient’shistoryshouldcontainasuitablecausesuchasrecenttraumaorsurgery.


• Longtermcomplicationsofahaemothoraxarechronicpleuralthickeningandheavypleuralcal-
cification(Fig10.14).




PlEuRAl disEAsE • 115


L1


Figure 10.14
frontal CXR of an adult male that developed pleural thickening and calcification following a right sided
haemothorax. note the dense pleural thickening with heavy calcification and loss of volume on that side of
chest.


Pleural calcification
• CalcificationofthepleuraisreadilyseenontheCXR,inparticular,wherethepleuralsurfaceis
inlinewiththeX-raybeam,i.e.overthehemidiaphragms,thelateralmarginsofthechestand
theapices(Fig10.15).




116 • THE WHO mAnuAl Of diAgnOsTiC imAging


L1


• Pleuralcalcificationonthemediastinalcontourisunusualbutpericardialcalcificationasasequel
ofpericarditismaybeobserved.


• Difficultymayarisewhenthepleuralcalcificationisenface,i.e.liesacrosstheX-raybeam.The
marginsofthecalcificationmaybevisiblebutsurroundanareaofdensitythatmaymimicasoft
tissuemass(Fig10.16).Insuchcircumstances,thepresenceofotherdefiniteareasofpleuralcal-
cificationmaybereassuringbutcouldequallybemisleading(Fig10.17).


Figure 10.15
frontal CXR and axial CT image of an adult male patient with a history of exposure to asbestos. Peripheral
calcified pleural plaques are relatively easy to identify (black arrows) but calcified pleural plaques en face to the X-
ray beam can convincingly mimic nodules, masses or in this case right hilar enlargement (white arrows).


Figure 10.16
frontal CXR and single axial HRCT image of an adult male patient with a strong history of previous asbestos
exposure. note the heavily calcified pleural plaques seen in the line of the X-ray beam that do not create any
diagnostic difficulty (black arrows). The plaque seen en-face (white arrow) overlies the hilum and is not so
readily diagnosed.




PlEuRAl disEAsE • 117


L1


Figure 10.17
frontal CXR of an adult male with asbestos related calcified pleural plaques (white arrows) clearer on HRCT
but note the density projected behind the heart (black arrow). it could easily be discarded as a calcified plaque
en face but as demonstrated on the HRCT image is clearly a soft tissue nodule. This distinction may have
been possible with a lateral CXR.


• Possiblecausesofheavypleuralcalcificationincludeprevioushaemothoraxorempyema(particu-
larlytuberculousempyema)andexposuretoasbestos(usuallybilateral).


Mesothelioma
• Mesotheliomaisamalignanttumourofthepleuradividedintothreetypeshistologically,epithe-
loid,adenomatoidandmixedcellularity.Itismostcommonlyaresultofexposuretoasbestos.


• Thefeaturesthatsuggestmalignantratherthanbenignpleuralthickeningare,thicknessgreater
than1cm,nodularorundulatingsurface,involvementofthemediastinalpleura,encasementof
the lungandevidenceofchestwall invasion.All these featuresmaybeappreciatedonaCXR
dependingonthesizeofthetumour(Fig10.18).


Figure 10.18
frontal CXR of an adult male with mesothelioma following exposure to asbestos. note the thickening of the
pleura best seen laterally. At the left base the pleural thickening is such that the left heart border is obscured
indicating the involvement of the mediastinal pleura, a reliable sign of malignancy. The axial and sagittal CT
images demonstrate the encasement of the lung.




118 • THE WHO mAnuAl Of diAgnOsTiC imAging


L1


• Anearlysignofmesotheliomaislossofvolumeoftheaffectedhemithorax.


• Othermalignantpleuraltumourstoconsiderincludemetastases,andextension/spreadofmalig-
nantthymoma.Thedistributionmaybedifficulttodistinguishfrommesotheliomabut inthe
lattertheoriginatingmalignantthymomashouldbevisibleonCXR.


• Benignpleuraltumourstoconsiderarepleuralfibroma(Fig10.19),pleurallipomaandprogres-
sivemassivefibrosis(PMF)(Fig10.20).ThesetendtobefocalinnatureandinthecaseofPMF
oftenmultifocalandassociatedwithdiffusepulmonarydiseasessuchasinterstitialfibrosis,silicosis
etc.


Figure 10.20
frontal CXR of an adult male patient with silicosis. note the diffuse nodules (black arrows) and progressive massive
fibrosis (Pmf), large patches of fibrotic lung causing focal dense opacities on the CXR (white arrows). (image courtesy
of Janet dacey).


Figure 10.19
frontal and lateral CXRs of an adult male with a left basal pleural fibroma. note the clearly defined margins (white
arrows) on all but the attachment to the chest wall (black arrow) which at surgery was found to be pedicular.
(images courtesy of Janet dacey).




L1


119


CHAPTER 11


Left heart failure


Cardiomegally
• Longstandingleftheartfailureresultsinaprogressiveenlargementoftheleftventricleandleft
atrium,thelatterparticularlywhenmitralvalvediseaseispresent.


• Enlargement of the left ventricle, which forms the left heart border on aCXR, results in an
increaseinsizeofthecardiacsilhouette(Fig11.1).


Figure 11.1
Frontal (PA) CXR of an adult female patient with a dual chamber pacemaker. The cardiac diameter is 19 cm
(normal up to 14.5 cm) and the cardiothoracic ratio (CTR) is 19/26.




120 • THE WHO mAnuAl OF diAgnOsTiC imAging


L1


• Theratioofcardiacdiametertothemaximumdiameterofthethoraciccage(cardiothoracicratio
or CTR) gives a gauge of the amount of cardiac enlargement and is of most use on serial
measurements.


• CXRevidenceforenlargementoftheleftatriumincludes(Fig11.2,11.3):


—enlargementoftheleftatrialappendageaffectingtheleftheartborder
—adoublerightheartbordercausedbytheprojectionoftherightwallofthe leftatrium


behindthesilhouetteoftherightatrium
—wideningofthecarina


Figure 11.2
Frontal CXR of a patient with early left heart failure. The magnified view demonstates the double heart
border, right atrial wall (white arrow) and left atrial wall (black arrow).




lEFT HEART FAiluRE • 121


L1


Interstitial oedema
• Inleftheartfailure,thereisanincreaseinthepressurewithinthecapillarybedofthelungresult-
ingintheaccumulationoffluidinthelunginterstitium.


• OnaCXR,thisisvisualizedasreticulationandmaybetoosubtletodetectwithconfidence(Fig
11.4).


Figure 11.3
AP semi-erect CXR of an adult patient in heart failure. note the prosthetic mitral valve and cardiomegally.
Elevation of the left main bronchus (black arrow) and loss of the normal concavity of the left heart border at
the level of the left atrial appendage indicate left atrial enlargement.




122 • THE WHO mAnuAl OF diAgnOsTiC imAging


L1


Figure 11.4
semi–erect CXR of an adult patient developing severe left heart failure. note the bilateral peri-hilar shadow-
ing, which falls short of consolidation and has a reticular pattern. This is interstitial oedema and progressed to
frank perihilar consolidation within hours.


Blood diversion
• Theincreaseinpressureintheinterstitiumcausescompressionofthecapillarybed;duetogravity
theeffectismoremarkedinthelowerlobescausingshuntingofbloodintotheupperlobes.


• Theresult isupper lobeblooddiversion,enlargementof theupper lobepulmonaryveins,and
lowerlobevasoconstrictionsuchthatthelowerlobepulmonaryveinsaresmallerthanthoseof
theupperlobes,areversalofthenormalstate(Fig11.5).


Figure 11.5
Frontal CXR of an adult patient with early left heart failure. The magnified views demonstrate dilated upper lobe veins
(white arrow) and constricted lower lobe veins (black arrow).




lEFT HEART FAiluRE • 123


L1


Consolidation
• As the degree of interstitial oedema increases, fluid accumulates in the alveolar air spaces and
interlobularseptainitiallycausinggroundglassopacity,anincreaseinlungopacity,progressing
toconsolidation/pulmonaryoedema,whereair-bronchogramsmaybeseen.


• Pulmonaryoedemaclassicallyhasabilateralperihilardistribution(Fig11.6).


Figure 11.6
Frontal CXR of a patient with pulmonary oedema in a classic perihilar distribution (horizontal black arrows).
The magnified view demonstrates air-bronchograms (diagonal black arrow).


Septal lines
• Theaccumulationoffluidintheinterlobularsepta,septallines,maybedifficulttodistinguish
fromtheinterstitialreticulationorobscuredbytheair-spaceopacification.


• Septallinesarebestseenatthecostophrenicangles,whereeachdiaphragmjoinsthechestwall.
Septallinesare2–3mminthicknessaround10mminlengthandextendtothepleuralsurface
wheretheycontactitat90degrees.


• Inmoreseverepulmonaryoedema,morecentralseptallinesmaybefound,whichradiatefrom
thehila.


Effusions
• Ultimatelyfluidaccumulatesinthepleuralspacecausingapleuraleffusion,which,intheearliest
stages,mayonlybevisibleonanerectCXRthrough“blunting”ofthecostophrenicanglebeing
themostdependentareaofthepleuralspace(Fig11.7).




124 • THE WHO mAnuAl OF diAgnOsTiC imAging


L1


Figure 11.7
Frontal CXR of an adult male with a small left pleural effusion secondary to developing heart failure. note the
“blunting” of the costophrenic angle (black arrow).


• Astheamountoffluidincreasesthepleuralspacegraduallyfillsupcausingincreasedopacityand
obscuringthediaphragmaticsilhouette.


• OnafrontalCXR,theeffusionwilltypicallyhaveameniscalappearance.


• Effusionssecondarytoheartfailureareusuallybilateral,rarelysymmetricalandcanbeunilateral,
particularlyinapatientwhofavourslyingononeside.




L1


125


CHAPTER 12


Cardiac


Recognition of cardiac abnormalities on a CXR depends upon appreciating changes in the medias-
tinal silhouette and/or observing the effect of the abnormality on the lung vasculature.


Coarctation of the aorta
• Coarctation of the aorta typically occurs at the isthmus just distal to the arch.


• Present from birth, the coarctation may significantly reduce the vascular supply to the trunk and
lower limbs such that collateral circulation develops via the intercostal arteries that originate from
the aorta distal to the coarctation.


• On a CXR, the aortic knuckle will appear small and may demonstrate the characteristic reverse
“3” appearance (Fig 12.1).


Figure 12.1
Frontal CXR of a young boy with coarctation of
the aorta. Note the reversed “3” sign (white
arrow), but due to the young age any intercos-
tals collateral vessels are not of sufficient size to
cause rib notching.


• The enlargement of the intercostal arteries, over time, causes erosion of the underside of the
adjacent ribs, visible on a CXR as rib notching (Fig 12.2). In children the rib notching may not
be apparent.




126 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


L1


Fallot’s tetralogy
• Fallot’s tetralogy describes the combination of four cardiac abnormalties; overriding aorta,


ventricular septal defect, pulmonary stenosis and right ventricular hypertrophy.


• On a CXR, the classical appearances are of a boot shaped cardiac contour as a result of the right
ventricular hypertrophy and a narrow cardiac root due to the overriding aorta (Fig 12.3).


Figure 12.2
Frontal CXR of an adult male patient with corrected
aortic coarctation. Note the small aortic arch (black
arrow) and the numerous rib notches (white arrows).


Figure 12.3
supine CXR of an infant with Fallot’s tetralogy. Note the boot shaped heart due to right ventricular hypertrophy and an
overriding aorta.




CARdiAC • 127


L1


Cardiomegally
• Enlargement of the heart is assessed on a CXR by measuring its maximum diameter (Fig 12.4).


Figure 12.4
demonstration of the cardiothoracic ratio (CTR).
A = cardiac size, B = thoracic diameter,
CTR = A/B.


• Heart size will vary with body habitus making absolute lower limits meaningless, but reasonable
upper limits for adults are 15.5 cm for females and 16 cm for males.


• Serial measurement of heart size is best determined by measuring cardiothoracic ratio.


• As the heart borders defining the mediastinal contours correspond to the left ventricle and right
atrium, left atrial enlargement may be difficult to appreciate on a CXR. Useful signs are enlarge-
ment of the left atrial appendage, a double right heart border and widening of the carina.
(Fig 11.2, 11.3).


• An enlarged fibrillating left atrium may develop mural thrombus, which can be identified if
calcification of the thrombus occurs (Fig 12.5).


Figure 12.5
Frontal and lateral CXR of an adult with a grossly enlarged left atrium, in fibrillation with an extensive mural
thrombus indicated by the curvilinear calcification following the contour of the atrium (black arrows). (images
courtesy of Janet dacey).




128 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


L1


Pericardial effusion
• A pericardial effusion is the accumulation of fluid, usually blood stained, in the potential space


between the two layers of pericardium.


• The pericardium is enclosed such that the fluid is trapped and any increase in volume is com-
pensated for by expansion of the pericardium or compression of the heart. As a result a pericardial
effusion can have a profound impact upon cardiac function.


• Pericardial effusions are difficult to appreciate on CXR. The most obvious signs are a change in
the shape of the heart to a more rounded contour (the globular heart) (Fig 12.6) and a rapid
increase in size of the cardiac silhouette.


Figure 12.6
Four images demonstrating the evolution of a large pericardial effusion. Top left is the normal CXR, top right there is
a change in the cardiac silhouette (white arrow) representing fluid accumulation around the left ventricle. Bottom left
the concave margin relating to the left atrial appendage has filled in, giving a globular shape to the heart, and
bottom right, there has been a further increase in heart size with a globular shape. Note the clearness of the left
heart border (white arrow), the silhouette is now formed by a sack of fluid surrounding the heart and less blurred by
cardiac motion.




CARdiAC • 129


L1


Pericardial calcification
• Causes of pericardial calcification are listed in Table 12.1.


Table 12.1 Causes of pericardial calcification


Pericarditis (TB, rheumatic fever, viruses)
Post-traumatic
uraemia


• On a CXR, there is curvilinear calcification on the surface of the heart.


• This should not be confused with calcification of a left ventricular aneurysm.


• Calcification en-face to the X-ray beam is difficult to appreciate but will be readily apparent on
a lateral CXR (Fig 12.7).


Figure 12.7
Frontal and lateral CXRs. There are two areas of curvilinear calcification (black arrows) that follow the contour
of the aortic knuckle and left ventrical but do not lie on the surface of these structures (white arrows). The
calcification is therefore inside the wall and due to calcified atherosclerosis in the aorta and calcified thrombus
in a left ventricular aneurysm, not pericardial calcification.


Ventricular aneurysm
• A ventricular aneurysm is usually the sequel to a myocardial infarct, typically the left cardiac


border changes shape and bulges.


• Mural thrombus is often present and may be visible if calcified (Fig 12.8).




130 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


L1


Figure 12.8
Frontal CXR of an adult with a large post myocardial infarct ventricular aneurysm. Note the bulging contour of the left
ventrical (white arrows) and the curvilinear calcification (black arrows) due to mural thrombus formation. (images
courtesy of Janet dacey).


Aortic aneurysm
• The appearance on a CXR of an aortic aneurysm depends upon the section of aorta involved.


• The ascending aorta forms part of the right mediastinal contour where aneurysmal dilatation
of the ascending aorta may cause a bulge in the mediastinal silhouette (Fig 12.9).


Figure 12.9
Frontal and lateral CXRs of an adult with aneurismal dilatation of the ascending aorta. Note the rounded right
mediastinal contour (white arrows) and the calcification within the wall of the ascending aorta (black arrows).




CARdiAC • 131


L1


• Aneurysmal dilatation of the arch of the aorta will manifest as an enlargement of the aortic
knuckle (Fig 12.10).


Figure 12.10
Frontal CXR of an adult male with a dissecting thoracic aortic aneurysm. Note the lateral margin of the aorta
(white arrows) representing an aneurysmal dilatation of the descending aorta. The posterior placement of this
abnormality is evident from the preservation of the hila point (horizontal black arrow) and the left heart
border (diagonal black arrow). The inset image is a coronal CT reconstruction of this case.




132 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


L1


Figure 12.11
Frontal CXR of an adult female. The descending aorta appears dilated but is actually of a normal calibre. The right hand
(medial) wall of the aorta is not seen, but is approximated by the grey line.


• The descending aorta lies behind the heart not contributing to the mediastinal contours but its
left border is visible lying adjacent to aerated lung. Bulging of this contour suggests aneurismal
dilatation, but unfolding of the aorta may mimic the appearance (Fig 12.11).




L1


133


CHAPTER 13


Pulmonary embolic disease


• TheCXRinacutepulmonaryembolus(PE)isoftennormalanditsmainvalueisinidentifying
otherpossiblecausesforthesymptomsthoughttobeduetoaPE.


• ACXR is required to accurately interpret a ventilation/perfusion scan if this is to be used to
diagnoseaPE.


• SomesignsontheCXRthatmayindicateaPEareperipheralwedge-shapedopacitiesrepresenting
infarctedsub-segmentalareasoflungthatmaycavitate(Fig13.1),pleuraleffusion,atelectasisand
paucityofvascularmarkingsintheregionofthePE.


Figure 13.1
Frontal CXR of an adult male patient with a left lower lobe pulmonary infarct that subsequently cavitated
(lower inset taken from CXR 3 weeks later).




134 • THE WHO mAnuAl OF diAgnOsTiC imAging


L1


Figure 13.2
Frontal CXR of an adult male with pulmonary hypertension. note the dilated pulmonary outflow tract causing an
abnormal left mediastinal border (white arrow).


• Chronicpulmonaryembolicdiseaseresultsfrommultiplesmallembolitothelungsoveralong
periodoftimemanifestinagradualdeteriorationofpulmonaryfunction.


• ThesignsassociatedwithanacutePEarenotafeature,butthedevelopmentofpulmonaryarte-
rialhypertensionmaybeevidentwithprominentproximalpulmonaryarteries(Fig13.2).




L1


135


CHAPTER 14


Mediastinal disease


• There is littlenatural contrast in themediastinumwithmostadjacent structuresofequivalent
densityandlittlelowdensityfatinbetween.


• As a result,most of the interpretation ofmediastinal pathology relates to the changes in the
interfacebetweenthemediastinumandthe lung,abnormalitiesthatdonotaffectthiscontour
orinterfacearenotreadilyappreciatedonaCXR.


• Asaresult,theextentofmediastinaldiseasemaybeunderestimatedonafrontalCXR.


Mediastinal tumours
• Therearemanysofttissueswithinthemediastinumallofwhichmaygiverisetotumours.


• Inthe interestofreducingthe listofdifferentialdiagnoses foranygivenmediastinalmass, the
siteofthetumourisausefuldiscriminator.


• Themediastinumismostconvenientlydividedintothreeregions.


• Thisdemarcation isbaseduponthestructures that liewithineachregionandthereforedefine
thelikelynatureofthepathologyintheregion,andcanbedescribedasfollows(Fig14.1):


• Anteriormediastinum-heart,thymicregion,pericardium


• Middlemediastinum-SVC,descendingaorta,hila,oesophagus,trachea


• Posteriormediastinum-spine,nerveroots




136 • THE WHO mAnuAl Of diAgnOsTiC imAging


L1


• Table14.1liststhemostcommontumoursineachofthoseregions.


Figure 14.1
The division of the mediastinum into anterior, middle and posterior compartments is easiest to consider in terms of
smooth curves drawn anterior to the spine and anterior to the trachea (inset image). However, the true demarcation is
somewhat more complicated and governed primarily by the anatomical structures that reside in each compartment.


Table 14.1 Causes of mediastinal masses


Anterior mediastinum Thymic tumour (thymoma, cyst,
fat, etc.)


Teratoma
Thyroid (2/3rd of retrosternal


extension)
Terrible lymph nodes (TB,


lymphoma)
middle mediastinum Aneurysm of aorta,
Tumour of trachea or main


bronchi
duplication-bronchogenic cyst.
Oesophageal lesions-achalasia/


hiatus hernia.
Posterior mediastinum mass arising from spine–tumour,


abscess etc.
neurogenic tumours
lateral thoracic meningocoele
Extramedullary haemopoiesis


(e.g. thalassaemia)
Bochdalek hernia, hiatus hernia




mEdiAsTinAl disEAsE • 137


L1


• On a frontalCXR, the site of amediastinalmass canusually bedetermined from the loss or
preservationofthevariousmediastinalcontoursandlines(seeearlier).


Hilar masses
• Thehilarpointhasbeendescribedearlier,atthissiteliethehilarlymphnodes.


• Nodalenlargementincreasesthedensityandsizeofthehilum(Fig14.2,14.3).


Figure 14.2
frontal CXR of an adult male with left hilar adenopathy secondary to renal cell carcinoma. note the increase
in size and density of the left hilum (white arrows).




138 • THE WHO mAnuAl Of diAgnOsTiC imAging


L1


Figure 14.3
frontal CXR of an adult female with sarcoidosis. note the bilateral hilar adenopathy with filling in of the concavity
normally associated with the hilar point (white arrows).




mEdiAsTinAl disEAsE • 139


L1


• Comparison between the hilamay assist the observer in decidingwhether the enlargement is
genuine,butonlyif theabnormality isunilateral.Oneshouldbewareofhilardiscrepancyasa
resultofrotationofthepatient(Fig14.4).


Figure 14.4
frontal CXR of an adult. note the apparent increase in the size and density of the right hilum (white arrow).
The appearance is due to rotation of the patient to the left, which has partially obscured the left hilum
making it look smaller than it is and revealing more of the right hilum, which when compared to the
obscured left hilum appears enlarged. note in the magnified image the relationship between the medial end
of the right clavicle (R), the medial end of the left clavicle (l) and the spinous processes (s). The increased
distance from s to l confirms left rotation.




140 • THE WHO mAnuAl Of diAgnOsTiC imAging


L1


Lymphadenopathy (Fig 14.5)


Figure 14.5
frontal CXR of an adult male patient with lymphoma. note the bilateral hilar adenopathy more evident on the
right. The true extent of the mediastinal adenopathy is less readily appreciated. On the magnified view, the
contours caused by the paratracheal and anterior mediastinal lymph nodes are marked (white arrows) and the
appropriate CT section is included (top inset image). The sub-carinal lymphadenopathy has caused a subtle
bulge of the azygo-oesophageal line (black arrows). The CT image at that level is the bottom inset image.




mEdiAsTinAl disEAsE • 141


L1


Mediastinal haemorrhage (Fig 14.6)


Figure 14.6
Top left: frontal CXR of an adult male following cardiac surgery; bottom left: lateral CXR taken at the same
time; bottom right: pre-operative CXR; top right: three post-operative CT images. note the clearly defined
lateral and posterior margins of the mediastinal haematoma (black arrows, the position above the heart
makes the posterior silhouette possible. The upper margin is ill-defined (vertical white arrows) as the
haematoma merges with the normal tissues of the superior mediastinum at no point causing an abrupt
change in tissue density as is found with the posterior and lateral margins. note also the more globular shape
to the heart post-operatively, compared to the pre-operative CXR, due to a pericardial effusion (diagonal
white arrows).




142 • THE WHO mAnuAl Of diAgnOsTiC imAging


L1


Mediastinal abscess (Fig 14.7)


Figure 14.7
frontal CXR and CT images of an adult male with extensive mediastinal abscesses, initially presenting with a
parapharyngeal abscess, which was drained at surgery. note the abnormal contour to the mediastinum (white
arrows) as the only sign of mediastinal pathology. The CT images reveal, as for the case of lymphadenopathy
earlier, how the CXR has underestimated the extent of the abscess. note also the classic appearance of the
pleural effusion.




L1


143


CHAPTER 15


Trauma


The chest X-ray in cases of trauma may reveal numerous significant complications of trauma. The
mechanism of injury should always be considered when reading a chest X-ray in the context of
trauma. The following signs may be identified:


• Fractures, potential cause of penetrating injuries and in some sites easily overlooked (e.g. the
spine)


• Consolidation indicating lung contusion


• Pneumothorax, pneumomediastinum, pneumopericardium and surgical emphysema-indicating
penetrating injury or airway rupture introducing air to these spaces either from the lung or from
outside the chest


• Haemothorax.


The following cases demonstrate the various results of trauma:


Lung contusion/laceration/fractures (Fig 15.1)


Figure 15.1
Frontal CXR of an adult male following a road traffic accident. Note the lung contusions (white arrows) but
also the fracture of a lower thoracic vertebral body (black arrows).




144 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


L1


Figure 15.2
supine CXR of an adult patient following a road traffic accident. Note the presence of air in the pectoral muscles (black
arrows vertical up), pneumoperitoneum (horizontal white arrows), subdiaphragmatic air (black arrow vertical down). The
left pneumothorax gives a sharp outline to the left heart border on this supine film.


Pneumothorax, surgical emphysema, pneumoperitoneum (Fig 15.2)




TRAumA • 145


L1


Haemothorax (Fig 15.3, 15.4)


Figure 15.3
supine CXR of an adult male who was shot in the chest with a shotgun. Note the radio-opaque shot. Of the
three chest drains present, the marked drain (black arrow) was inserted to drain a haemothorax as a result of
the trauma. Note the increased opacity in the left hemithorax due to haemorrhage into the upper and mid
zone pleural space. The distribution indicates the non-simple nature of the fluid in this case blood.


Figure 15.4
Frontal CXRs of an adult male victim of a stabbing. The complete opacification of the right hemithorax on the
left CXR was due to a large haemothorax. Note the shift of the mediastinum to the left and deviation of the
right main bronchus (black arrow). in the right hand image, the haemothorax has been partially drained and
the mediastinal position has returned to normal.




146 • THE WHO mANuAl OF diAgNOsTiC imAgiNg


L1


Pneumopericardium and pneumomediastinum (Fig 15.5)


Figure 15.5
Frontal CXR of an adult male following a road
traffic accident. Note the air tracking inferior to the
heart (black arrow), the pericardium outlined by
lung on one side and air on the other (white arrow
diagonal down) and the mediastinal air (white
arrows horizontal).


Bullet wounds (Fig 15.3, 15.6, 15.7)


Figure 15.6
Frontal and lateral CXR of an adult male who was shot through the anterior left upper abdomen. The bullet
traversed the diaphragm damaging the phrenic nerve causing diaphragmatic paralysis (white arrow), narrowly
missed the heart and lodged in the posterior chest wall (black arrow).




TRAumA • 147


L1


Figure 15.7
Frontal CXR of a patient shot in the abdomen 20 years earlier. The bullet has migrated via the iVC and right
atrium to lodge in the right ventricle (black arrow).


The likelihood of any of these complications will depend upon the mechanism of injury, whether
penetrating or blunt trauma, but all the possible complications should be considered in the context
of a CXR for trauma.


Further reading
Hansell DM; Armstrong P; Lynch DA; McAdams HP, Imaging Diseases of the Chest 4th Edition


(Mosby)


Wright FW, Radiology of the Chest and related conditions (Taylor and Francis)


Grainger RG; Allison DJ; Adam A; Dixon AK, Diagnostic Radiology, a textbook of medical imaging
(Churchill Livingstone)




The WHO
manual of
diagnostic
imaging


RadiogRaphic
anatomy


and inteRpRetation
of the chest and
the pulmonaRy


system


ISBN 92 4 154677 8


W
H


O
m


a
n


u
a


l O
f d


ia
g


n
O


stic
im


a
g


in
g


R
a


d
Io


g
R


a
ph


Ic
a


N
a


to
m


y
a


N
d


IN
teR


pR
eta


tIo
N


o
f th


e c
h


eSt a
N


d
th


e pu
lm


o
N


a
R


y
Sy


Stem


WHO


Who in collaboration with the international commission for Radiologic


education (icRe) of the international society of Radiology (isR) and other


members of the global steering group for education and training in


diagnostic imaging is creating a series of “manuals of diagnostic imaging”.


the full series of manuals will primarily cover the examination techniques


and interpretation of conventional diagnostic X-ray procedures. these


manuals will replace and update the WHO Manual of Radiographic Inter-


pretation for General Practitioners and the WHO Manual of Radiographic


Technique.


the present volume in the series, the manual Radiographic Anatomy and


Interpretation of the Chest and the Pulmonary System, provides an ex-


haustive description of radiographic normal anatomy as well as the most


common pathologic changes seen in the chest including trauma, tumours,


congenital and developmental disorders.


Backed by high-quality reproduction of radiographs, this manual will


prove essential reading to general practitioners, medical specialists,


radiographers and radiologists in any medical settings, although focusing


specifically on needs in small and mid-size hospitals.




Copyright © 2017 Engineering World Health. All Rights Reserved.